International Journal of Environment and Sustainable Development (43 papers in press)
Management of climate change risks in Indian organisations: A proposed framework
by Aditee Potdar, Seema Unnikrishnan
Abstract: This study focuses on determining how climate change risks affect Indian organisations. A framework consisting of four steps (monitoring, analysis, evaluation, and implementation) is proposed to guide organisations to address the climate change challenge. Climate change risks, drivers, and mitigation actions were evaluated by designing a questionnaire and overseeing it to 257 manufacturing organisations. The findings from this study suggest that energy and its price may influence a major impact of climate change challenge. The respondents view on competitive risk is found as the most critical climate change threat. Top management commitment is viewed as a key driver to propose a likely framework. The mitigation action that most organisations have undertaken is energy efficiency. Further, multiple regression analysis shows a significant relationship between climate change risks and drivers, and climate change risks and mitigation activities. The outcomes from this study will be useful for organisations to determine the potential risks and ascertain further actions to mitigate them for India and elsewhere.
Keywords: climate change risk; climate change impacts; drivers for climate change mitigation; mitigation actions; business organisations.
Impacts of Health and Economic Costs on Street Children Working as Waste Collectors in Dhaka City
by Md. Mahmudul Alam, Mohammad Saeed Hossain, Nurul Islam, Md Wahid Murad, Niaz Ahmed Khan
Abstract: In the developing world, many children are working in risky, unhealthy and hazardous environments, which impact significantly on their lives and at great economic cost to them. To understand what is happening in Bangladesh, this research investigates the health impacts and access to health services by children who work in the street waste collection industry in Dhaka, the capital city. This study uses both qualitative and quantitative data analysis techniques. Qualitative data were collected through expert interviews and personal observations, while quantitative data were gathered through a face-to-face questionnaire survey given to 50 street children who collected waste at the landfill site located in Dhaka citys Matuail area. The results indicate that 94% of these children have suffered from many health problems, such as fever and fatigue due to tiredness, dizziness, and vomiting. Consequently, a significant portion of their daily income is spent on medical treatment. This study suggests that the waste collection system must integrate modern technological, health and environmental resources so that: firstly, they do not harm waste collectors; and secondly, rehabilitate the street children and give them better access to acceptable basic amenities. This is a priority the city authorities.
Keywords: Street Children; Landfill; Waste collection; Waste management; Health services; Health cost; Dhaka City.
The role of energy efficiency in the management of water resources of the Syr Darya river basin
by Eunice Ramos, Annukka Lipponen, Mark Howells, Constantinos Taliotis
Abstract: A motivation for integrated resource assessments is that they can capture indirect effects. Policies in one sector are often developed with limited consideration of their indirect impact on other sectors. This work focuses on the analysis of the implications of electricity efficiency measures on other sectors. The spatial scope includes the four states that share the Syr Darya River basin.
Different interests dictate the management of water resources in the basin. Water resources are the backbone of electricity generation upstream. They are necessary for irrigation downstream. These two uses require water at different times of the year. Upstream nations produce hydroelectricity in winter. They empty reservoirs, leaving little water left during spring and summer. Yet in spring and summer, water is needed for irrigating agriculture. The study investigated options to decrease the need for electricity upstream. Thereby reducing hydro generation requirements and, in turn, reducing winter water requirements. Electricity needs were assumed to be reduced in a scenario that increased the efficiency of energy use. Further, the expansion of regional electricity trade in the period of 2015 - 2030 was also considered as an option to reduce the need to use hydropower in winter. The scenarios were simulated by developing and using a multi-country electricity system model. The model was generated using the Open Source energy Modelling System (OSeMOSYS). The results show that with aggressive energy efficiency measures, less hydro capacity is needed and less water required in winter. The water is stored and available for summer use at no extra cost to the upstream country.
Keywords: transboundary river basin cooperation; energy efficiency; energy systems modelling; water resources management.
Examining the Motivational Factors of Green IT Intention in Malaysia
by Hartini Abdul Jalil, Wan Edura Wan Rashid, Erne Suzila Kassim
Abstract: This study aims to examine the influence of eco-motivational factors measured by eco-efficiency, eco-effectiveness, eco-process and eco-brand on the intention to adopt Green IT. To have a better outcome on the Green IT, a quantitative analysis was performed. The results suggest that all relationships between eco-efficiency, eco-effectiveness, eco-process and eco-brand explored (e.g. predictors) were supported except for eco-process. In comparing the strength of the predictors, eco-brand plays the most vital role, followed by eco-effectiveness and eco-efficiency. Henceforth, all study predictors recognised as the champion in Green IT matters. By using the study outcomes, a Green IT adoption framework could be established for safeguarding the environment from unnecessary e-waste. The study contributes to the environmental literature in an area that has become a fundamental issue and yet lacking in the particular research outcome. The findings of this study will be useful for the policymaker to oversee the interaction between economic drive, Green IT and sustainable environment.
Keywords: Green IT intention; Green IT motivation; eco-efficiency; eco-effectiveness; eco-process and eco-brand.
UTILIZATION OF OIL-BASED WASTE FOR BIOSURFACTANT PRODUCTION
by Tejas Suryawanshi, Rutuja Yelmar, Shiney Peter, Conceetha Sequeira, Sharline Johnson, Gunjan Dutt, Berin Babu, Pency Martina
Abstract: Chemical surfactants produced in large amounts globally have severe adverse effects on environment and human health due to their non-degradable and toxic nature. Eco-friendly biosurfactants with high stability, biodegradability, and low toxicity are the need of the hour. However, biosurfactants are less preferred due to high substrate cost and cumbersome extraction process. This study focused on repurposing of lipid-rich waste like coconut oil cake, rice husk and used cooking oil as a substrate for bacterial biosurfactant production. P. aeruginosa and B. subtilis were evaluated for production and P. aeruginosa was found to be an efficient biosurfactant producer. Among the substrates, coconut oil cake gave maximum yield of 19 mg/ml. The study also focussed on optimization of biosurfactant extraction using organic solvents and precipitation methods. The yield obtained was maximum using chloroform and methanol (2:1) extraction method. The product obtained was characterized using standard methods and confirmed for its properties. It also exhibited promising antimicrobial activity against gram-positive species.
Keywords: Biosurfactants; Coconut oil cake; Organic solvent method; P. aeruginosa; Antimicrobial activity.
Potential of CO2 mitigation in concrete containing recycled aggregates
by Bruno Luis Damineli, Javier M. Pablos
Abstract: The replacement of natural aggregates with recycled ones is a strategy for developing sustainable concrete formulations, which could decrease landfill disposal of construction waste. However, the increase of recycled aggregates (RA) content in concrete frequently leads to an increase in cement content - which is the heaviest environmental burden of concrete due to CO2 emissions. This study presents a strategy for a better engineered concrete design approach that could allow using RA without increasing cement content. From a more detailed aggregate characterisation, a known particle packing theory could be applied to optimise the concrete packing of particles, allowing a decrease in cement content. The eco-efficiency of cement use was assessed by Binder Index (BI) - the ratio between binder content (environmental load) and compressive strength (performance indicator). Better-engineered concrete could provide similar efficiency of cement use in packed concrete formulations with 100% low-quality RA compared to ordinary ones with 100% natural aggregates.
Keywords: concrete; aggregate; waste treatment; particle size distribution; mixture proportion.
Economic Determinants of Deforestation in Developing Countries
by Collins Ayoo
Abstract: Forests are an important natural resource that provide to society several valuable goods and services that include timber, fuel, food, chemicals, medicines, climate regulation, and soil protection. Forests in several developing countries are however being destroyed at a rapid rate with adverse impacts such as increased soil erosion, loss of biodiversity, and increased emissions of greenhouse gases that cause climate change. The causes of deforestation are complex and diverse and depend on the socioeconomic, political, cultural, legal and institutional contexts of the countries in which the affected forests are situated. This paper examines the deforestation trends in developing countries and discusses the key drivers of deforestation in these countries. The paper also identifies and discusses measures that can be used to reduce deforestation. The insights that this paper provides can be practically applied to formulate policies, strategies and plans for improving forest management and enhancing both their economic contribution and their role in sustainable development.
Keywords: Forests; deforestation; sustainable development; biodiversity; poverty.
Special Issue on: ICEBSS 2017 Climate Change, Conflicts and Food Security in Developing Economies
The impact of spatial development on water pollution: a comparative assessment of river water quality in two municipalities in Malaysia
by Hamidi Ismail, Tuan Pah Rokiah Syed Hussain, Muhammad Subhan
Abstract: This study is aimed at understanding different level of pollution of the river water in two municipalities in Malaysia as a result of spatial development activities. Both municipalities represent the central and southern zones of Peninsular Malaysia which are prone to river water quality problems due to logging, land clearing and livestock farming. Frequency and trend analysis are applied to the data obtained from the Department of Environment (DOE) and measurement of the water quality in the field is conducted in both areas. The results show that the rivers in both municipalities are experiencing deterioration of water quality. The decline in the river water quality is closely related to human activities and the ineffective environmental management system by the government. The apparent environmental problems indicate that the present management system should be improved to create an urban ecosystem which is really capable of addressing the issues of river water pollution.
Keywords: spatial development; river management; urban management; water pollution; water quality; sustainable development; Malaysia.
Special Issue on: 5th Conference in Economics of Natural Resources and Economics Recent Developments on the Energy Consumption and Economic Growth Nexus
Measurement of green industrial performance: an enhanced GIP index
by Jaime Moll De Alba, Valentin Todorov
Abstract: The green industrial performance (GIP) index provides a tool to analyse and compare the performance of economies in terms of green manufacturing. The demands for and expectations for sustainable development seem not matched with the existence of an analytical framework to measure how green the industrial sector of a given economy is. In this article, we introduce significant methodological improvements to the GIP index. In previous research, we developed and tested a set of indicators covering the various facets of the green industrial performance of economies. We also introduced a composite index to rank economies according to their green industrial performance. In this article, we address some limitations of the index. To improve the non-satisfactory data coverage, we investigate alternative imputation methods. We also refine our list of 'green' products; and test new outlier detection methods.
Keywords: inclusive and sustainable development; composite index; green industry.
Alternative forms of sustainable development: the case of thermal tourism
by Georgakopoulou Stavroula, Delitheou Vasiliki
Abstract: Thermal tourism is a special form of providing tourist services at special facilities that use recognised thermal natural resources. Thermal tourism blooms in Europe with pioneer country Germany. There are 1,400 developed bathing sites in Europe, visited by millions of patients from all over the world. This industry employs about 750,000 people and has an annual turnover of approximately 45 billion euros. In Greece, thermal tourism is an important part of the country's cultural heritage and not only because Greece is one of the richest countries in natural sources with excellent quality water. Despite the fact that Greece is the first country in Europe in the quality and uniqueness of natural thermal resources, its thermal tourism is declining. Furthermore, in this article, efforts will be made to identify the causes that contribute to the reduction of thermal tourism, as well as to draw some conclusions with a view to improving and sustaining the thermal tourism.
Keywords: alternative tourism; thermal tourism; sustainable development.
Special Issue on: SUSCOM-2019 Sustainable Computing for Environmental Systems
Sustainability of textile waste-water management by using an integrated fuzzy AHP-TOPSIS method: A case study
by PUNYASLOKA PATTNAIK, Govind Sharan Dangayach
Abstract: The textile industry is quickly growing worldwide and has a universally beneficial effect on the economy. The waste-water generated with the growth of the textile industry can cause considerable health and environmental issues if it is not treated properly. Generally, physical, biological, and chemical processes are used independently or in combination to treat textile waste-water. The efficiency of any treatment process depends on the working criteria. In this paper, we implemented a new hybrid methodology based on the fuzzy analytic hierarchy process (FAHP) and fuzzy technique for order preference by similarity to ideal solution (FTOPSIS) to help workers in textile industries select the optimal waste-water treatment process. To illustrate how this hybrid methodology can be used to address the waste-water treatment problem, we conducted a case study involving 11 assessment criteria and four treatment process used in the textile industry in India. Comparative analysis indicated that the survey overall mean was slightly lower than the overall mean for selected companies in the treatment process.
Keywords: Textile industry; waste-water treatment; FAHP; FTOPSIS; case study.
Performance Analysis of HCCI and PCCI Engine using Computational Fluid Dynamics
by Pushpendra Upadhyay, K.B. Rana, B. Tripathi
Abstract: Increasing fuel cost and environmental pollution through toxic emissions has brought the attention of automobile researchers to develop advanced engine technologies, which can yield high fuel efficiency and low emission simultaneously. Some advanced combustion technologies i.e., homogeneous charge compression ignition (HCCI) and pre-mixed charge compression ignition (PCCI) are being proved as promising engine strategies for same. However, it is still not clear that which combustion strategy is suitable as a practical alternative combustion technology. In the current study, numerical simulation for a three dimensional model of internal combustion (IC) engine consists of inlet valve, exhaust valve, inlet manifold and exhaust manifold, was carried out to analyze the HCCI and PCCI strategies using ANSYS 16.2. The computational fluid dynamics (CFD) analysis was carried out for different swirl number and essentially moderate values of the engine speed. The converged results of both the combustion strategies were compared for different wall adjacent temperature, mass average static pressure, apparent heat release rate and mass average turbulent kinetic energy. The outcome of simulations reflected that a PCCI combustion strategy is better than HCCI combustion strategy at lower rpm, while at the moderate and higher values of engine rpm, HCCI combustion strategy demonstrated better performance in terms of temperature, pressure and turbulent kinetic energy. Interestingly, the exergy destruction rate was observed higher in case of homogeneous charge compression ignition combustion strategy.
Keywords: HCCI engine; PCCI engine; CFD; Simulation; Crank angle.
Detecting diseases in plant leaves: An optimized deep-learning Convolutional Neural Network Approach
by Saraansh Baranwal, Anuja Arora, Siddhant Khandelwal
Abstract: A country's economy relies heavily on its agricultural productivity. Most of the crops consumed daily by the population are prone to diseases. Identifying and preventing the disease at an early stage is a challenge even for the expert's eye. Therefore, an appropriate system is needed to detect plant disease in its initial stages. This paper employs the approach of Convolutional neural networks to automatically detect and address the issue. Images for various plants covering 35 different classes of plant diseases and a total of 29,180 RGB images of diseased and healthy plant leaves has been used for the purpose. Image filtering, compression, and data generation techniques have been used to further increase the training dataset and achieve high accuracy across all classes. Net accuracy of the model reaches a 98.34% success rate on the entire dataset. The data has been sampled and generated from severely downsized images, with a significant focus on speed as well as accuracy.
Keywords: plant leaf; disease detection; leaf images; machine learning; convolutional neural network; LeNet; Keras.
Special Issue on: AIC 2018 Innovations in Sustainable Development Approaches
The influence of environmental management accounting practices on environmental performance in small-medium manufacturing in Malaysia
by Rapiah Mohamed, Che Zuriana Muhammad Jamil
Abstract: The purpose of this study is to investigate the influence of environmental management accounting (EMA) practices on environmental performance in the small-medium sized (SME) manufacturing sector. The empirical data was collected through structured questionnaires that were distributed to the managers. The study results reveal that physical EMA has the highest mean score compared to monetary EMA, however, unfortunately the EMA practice is not at an encouraging level in Malaysia. The regression results indicate that both types of EMA practices (monetary and physical) have a positive and significant effect on environmental performance. Thus, this study demonstrates the importance of EMA in enhancing environmental performance. The study results are valuable to policy makers, managers of manufacturing SMEs and other sectors to appreciate EMA practices. The study findings contribute to a growing body of literature on EMA within the Asian context, particularly, Malaysia. Finally, this study shed lights on the extent to which EMA tools has been used amongst manufacturing SMEs and provides a good foundation and framework for future studies.
Keywords: environmental management accounting; EMA; environmental performance; small-medium manufacturing; Malaysia.
Islamic bankers' green behaviour for the growth of green banking in Malaysia
by Qaisar Ali, Shazia Parveen, Aslan Amat Senin, Muhammad Zaki Zaini
Abstract: Rising concerns for environmental sustainability (ES) demand that Islamic finance converts its business model to ethical finance. The conversion of a business model is unattainable without employees' positive attitudes and willingness to adopt the green banking approach. This study aims to promote ES implications for Islamic bankers and encourage Islamic banks to adopt a similar approach. The main objective is to explore green behaviours among Islamic bankers and the influence of these behaviours on green banking growth in Malaysia. Data were collected from 55 Islamic bankers using a survey questionnaire. The findings show that Islamic bankers' inclusive green behaviour significantly influences green banking growth. All five types of green behaviours (e.g., conservation, work sustainability, avoiding harm, influencing others and taking initiative) have a significant positive impact on green banking growth. Regulators and policymakers may adopt these findings to develop green banking regulations in Malaysia and other locations with similar economic settings.
Keywords: Islamic bankers; green behaviour; green banking; Malaysia; growth.
Do green human resource management practices contribute to sustainable performance in manufacturing industry?
by Noor Ullah Khan, Mansoor Nazir Bhatti, Asfia Obaid, Abdul Sami, Abrar Ullah
Abstract: Sustainable performance is a key area of concern for Malaysian manufacturing firms in addressing environmental issues. The goal of this study is to examine the direct relationship between green human resource practices such as green selection and recruitment, green training and development, green assessment and sustainable performance. A quantitative research design is employed using survey primary data. Primary data collected from 248 ISO-14001 certified Malaysian manufacturing firms and analysed by SEM technique using statistical tools. Research findings confirmed a significant direct positive relationship between green human resource practices and sustainable performance within the selected firms. This study adhered recommendations and directions for future research with inherent limitations. The findings from this study will be useful for Malaysian ISO-14001 certified firms and elsewhere with a similar economy.
Keywords: green human resource practices; green selection; green training; green rewards; sustainable performance; triple bottom line; TBL.
Special Issue on: ICMES-2018 Advances in Environmental and Biotechnological Sciences in a Sustainable Development Context
Variation in atmospheric air ion and its index of pollution during morning time (06:00 to 08:00 IST) in the sugarcane area at rural station Bhilawadi (16.5oN, 74.2oE)
by GAJANAN PATIL, SUBHASH PAWAR, Onkar Gurav, JALINDAR BHOSALE
Abstract: The present paper reports the diurnal variation in +ve and -ve air ion concentration in Sugarcane field (Genus: Saccharumspp, Variety: CO86032 (NAYANA)) in the vegetation area situated at rural station Bhilawadi (16.5oN, 74.2oE), India. It is a hybrid variety of CO62108 and CO671. We utilized Air Ion Counter to measure air ions in the field of sugarcane vegetation. In addition to this, we have calculated the pollution index which was found below one for sugarcane area and is healthier for human health. Further, it is found that -ve air ion concentration were greater than +ve air ions. It is due to ionization, photosynthesis, transpiration and radon exhalation process by sugarcane. It is well believed that -ve air ions are beneficial for human health. That is why most of the people use artificial air ion generator in living room or their work places. The results presented in this study suggests that the open environmental air or especially the sugarcane area exhibits large concentration of -ve air ions which are essential for human health. Though all living beings interact with environment, only human beings have less interaction with the environment, so attempts should be made to use natural resources to have better health.
Keywords: Air ions; Sugarcane; Radon; Ionization; Transpiration; Pollution index; Environment.
Bio-chemical changes in sugarcane pressmud combination and its assessment on Chick-pea and Spinach variety
by AMOL CHOUGULE, SHEKHAR MALI, Pallavi Bhosale, P.D. RAUT
Abstract: The study was carried out to understand the influence of pressmud enriched with isolated microflora of pressmud on laboratory scale pot experiments with Chickpea, Cicer arietinum and Spinach, Spinacia oleracea and recorded physico-chemical characters of soil and the phyto-chemical characters of Chickpea and Spinach. Initially, physico-chemical characters of pressmud (PM), composted pressmud (CPM) and enriched composted pressmud (ECPM) were studied for pH, moisture content, water holding capacity, total organic carbon, organic matter, nitrogen, potassium and phosphorous. Experiments were conducted with combinations of soil without pressmud (T0), soil with CPM (T1) and soil with ECPM (T2). T2 shows maximum i.e. 2.01 %, 1.03 % and 0.29 % of NPK. T2 observed promising growth for chlorophyll, ascorbic acid, polyphenols, proline, protein, indole acetic acid, total amino acids and flavonoids. It also resulted in maximum Chlorophyll content 12.43 mg / 100 gms, and 112.94 mg / 100 gms, Ascorbic acid 1235 mg / 100 gms and 1332 mg / 100 gms, Flavonoids is 0.38 mg / 100 gms and 0.35 mg / 100 gms and Amino acids 1.80 mg / 100 gms and 0.58 mg / 100 gms for Chickpea and Spinach respectively. The experiments suggest that the combination of soil with ECPM gives good results and can be practiced in the fields.
Keywords: Keywords: Pressmud; Enriched Pressmud; Compost; Chickpea; Spinach.
Special Issue on: BEST2019 Advances in Waste Management and Treatment Technologies
TREATMENT OF WASTEWATER WITH MODIFIED CONSTRUCTED WETLAND SYSTEM AS A TERTIARY TREATMENT UNIT
by J.S. Sudarsan, R. Annadurai, Subramanian Nithiyanantham, M.G. Prathap, G. Sudharson
Abstract: Most of the efforts taken for towards effective treatment of wastewater have mainly been focused on towards expensive treatment processes like membrane filtration. Conventionally, wastewater is treated by physical, chemical and biological processes that utilise a lot of energy and capital. Incorporation of constructed wetlands into the sewage treatment process is done in order to mimic processes found in the natural ecosystems where wetland plants and their associated micro-organisms remove pollutants from wastewater. Vegetation in a wetland provides a substrate upon which microorganisms can grow, they break down organic materials. These organisms and natural chemical processes are responsible for approximately 90 percent of pollutant removal and waste breakdown in nature. This research work has been undertaken with a view to integrating the natural ecosystem into the existing treatment plant on a large scale, which will be instrumental in minimizing the use of machineries and reducing high investment and operating cost as well as energy consumption. The greywater can be reused purification but the currently adopted process to obtain secondary water source is both complicated and expensive. In order to minimise the cost and energy spent on the conventional process constructed wetlands can be used as a tertiary treatment unit of the sewage treatment process.
Keywords: cost analysis; wetland; vegetation; wastewater; model.
Experimental Investigation on Cooling Cogeneration Plant for low Temperature Waste Heat Recovery Process
by Shankar R
Abstract: The integration of the aqua-ammonia vapor absorption refrigeration cycle (VAR) and Kalina cycle system (KCS) at suitable conditions minimizes the components and input energy. This integration will solve the cooling and power demand faced by the emerging world. The aqua-ammonia VAR cycle and Kalina Cycle are integrated to produce a combined output of power and cooling at low temperature is proposed which can be used for the heat recovery process. Three pressure viz condensing pressure, source and sink pressure is maintained for the operation of the system. The common components of the pump, separator, superheater, turbine, condenser, and absorber are shared. Aqua-ammonia is used as a working fluid for combined power and cooling cycle, in that 25% is ammonia, and 75% weight capacity is water. The vapor ammonia produced in the separator runs the turbine after heated up in the superheater and expanded from source pressure to condensing pressure. The liquid ammonia is further expanded from condensing pressure to sink pressure to achieve the cooling effect. The power and cooling output of 3.15 kW and 9.0 kW are obtained experimentally at the hot fluid supply temperature of 129 ?C. The maximum energy utilization factor (EUF) of 0.225 is obtained and it is further increased by rising ammonia concentration and hot fluid supply temperature. The proposed system is suitable for both domestic and industrialist applications.
Keywords: VAR; Aqua-ammonia; Cogeneration; heat recovery; combined power and cooling; Kalina cycle etc.
Special Issue on: ICONRER-2019 Smart Use of Resources and Strategies for Sustainable Development
Experimental studies on combustion duration and ignition delay period for a newly synthesized gomutra emulsified diesel
by Amit Jhalani, Dilip Sharma, Shyamlal Soni, Pushpendra Kumar Sharma, Digambar Singh, Sumit Sharma
Abstract: Aligning to water-in-diesel emulsion technology, a newer work has been proposed in this study by introducing gomutra-in-diesel emulsion (GMD emulsion) fuel for application in CI engine. Experimental investigations have been performed in this study for ignition delay and combustion duration to understand the underlying mechanisms of combustion with this fuel. The complete work has been performed over a VCR (variable compression ratio) stationary diesel engine. Emulsions of different gomutra-in-diesel (5%, 10%, 15% and 20%) concentrations were taken for the study. The ignition delay was found to be 24
Keywords: Diesel engine; Gomutra; Combustion Duration; Ignition Delay; Emissions; Emulsified fuel.
A review on Emissions Reduction Techniques used in Internal Combustion Engines
by Digambar Singh, Dilip Sharma, S.L. Soni, Sumit Sharma, Pushpendra Kumar Sharma, Amit Jhalani
Abstract: Continuous growing population and a rise in living standards are creating widespread use of vehicles. Motor vehicle emissions contribute significantly to air pollution and other adverse environmental and health effects. The primary contaminants from internal combustion (I.C.) engines are NOx, CO, CO2, unburnt hydrocarbons (HC), and PM. Their control strategies were considered seriously throughout the discussion. This analysis summarizes emissions from both compression ignition (C.I.) and spark ignition (S.I.) engines with government-setting emission regulatory standards. This article also gives detailed insight into pollution monitoring methods and their control policy for both C.I. and S.I. engines. Emissions from S.I. engines are more harmful to human health, with more CO and HC emissions in comparison with C.I. engines. CO emissions are insignificant in C.I. engines due to lean-burn nature. High temperatures and significant oxygen supply in the combustion chamber make C.I. engines prone to NOx emissions. This analysis will help researchers to obtain comprehensive emission and their reduction methodologies information for I.C. engines.
Keywords: C. I. Engine; S. I. Engine; Emissions; Emission Measurement; Emission reduction techniques.
A new methodology to find out cooking energy need for a rural household
by Hemant Raj Singh, Dilip Sharma, Shyam Lal Soni
Abstract: In the era of global warming and ever rising energy demand climate justice has become the need of the hour. Sustainable solution has become the key to the success for environment. Cooking sector is considered as one of the major energy consuming sector in developing and underdeveloped countries. Inherently associated hazardous effects and energy inefficiencies of conventional biomass cooking system forces unconventional cooking energy to becoming popular day by day. In this study a new census based approach is being presented to find out cooking energy requirement of a single rural household of India. Mathematical modelling is being done while scrutinizing coke, firewood and chips, coal, and LPG as cooking fuel and by eliminating charcoal, petrol, diesel and kerosene. Exact heat Energy required per household per meal has been achieved 4212.02 kJ. Out of which vaporization of water, heating food to boiling temperature and convection losses from vessels shares 1474.21 kJ, 842.40kJ and 1895.41kJ respectively. Outcome of this study can serve a baseline for inventors, researchers and policymakers of microscale unconventional/solar cooker.
Keywords: Stove; Cooking Energy; Modelling; Household; Solar cooking system; cooking fuel.
Design, development and performance analysis of modified solid fertilizer spreader equipped with air blower
by Chandan Kumar, K.B. Rana, M.L. Meena
Abstract: Development in the agricultural sector is one of the powerful ways to enhance the economic growth of country. In recent years remarkable revolution has been seen in traditional methods of agriculture such as irrigation systems, seed planting, pesticides and sprays. Cultivation includes various processes in which fertilization is one of the important processes. The fertilization is tedious and expensive process, as generally carried out by traditional method which requires lots of manual efforts. It is also very dangerous for the human health and environment, and may cause of various musculoskeletal disorders in worker's body. However, few manual and mechanically operated machines are available, but they have also some problems associated with them. Therefore, keeping in mind the needs of farmers and workers, it was proposed to design an electric power operated fertilizer spreading machine which would help them to work easily in environmentally friendly way. The performance of modified solid fertilizer spreading machine equipped with air blower was evaluated on the basis of parameters i.e., spreading distance, fertilizer discharge rate, spreading time, and operational labour cost involved in the process. From the experiments, it was found that this machine can spread the fertilizer (Urea) up to 8 m distance with discharge rate of 1050 gm/min, which is more than enough for fertilization for almost all types of crops. Using FSM, reduction in time required for fertilization (66 %) and operational labor cost (70 %) was also observed as compared to the traditional method.
Keywords: Agriculture; solid fertilizer; DAP; urea; potassium-chloride; spreading machine.
Design of four-bar mechanism for vibratory tillage cultivator using five precision position method for path generation problem
by N. R. N. V. Gowripathi RAO, Abhijeet Kumar, Himanshu Chaudhary, Ajay Kumar Sharma
Abstract: Agriculture is the backbone of Indian economy. There are different agricultural operations which play a critical role in the overall crop development. Farmers are in search of sustainable technologies which can contribute to their overall economy and improve the efficiency. The paper deals to design a vibratory cultivator that saves the time and energy for the farming community. A four-bar mechanism is designed and developed to vibrate the cultivator. Proper analytical synthesis procedure is adopted, such as five precision position method for a particular vibratory tillage trajectory available from the literature. The dimensions of four-bar mechanism are validated through MATLAB, and it is confirmed that the designed four-bar mechanism traces the path accurately for vibratory tillage operation.
Keywords: Tillage; four bar mechanism; synthesis; precision position; trajectory.
A comparative analysis of game theory techniques for study of energy interactions in interconnected microgrids
by MOHAMMAD ZEESHAN, Majid Jamil
Abstract: The growing energy needs of society can be met with one or more microgrids working in conjunction. A need of a trading and scheduling mechanism for energy exchange among microgrids for sustainable development of the consumers is required. Game theory techniques have been widely utilized to study this interaction among microgrids. This paper seeks to analyze the different game theory-based energy trading techniques to elaborate on such models efficiencies. The study is based on renewable energy generation and consumption in Denmark. Lexicographic egalitarian solution is proposed as a bargaining solution for two participating microgrids in an energy trading game. A comparison is performed between the proposed model and conventional techniques for inter-microgrid trading. The proposed bargaining solution depicts a fairness index of 0.974 compared to 0.946 for the Nash solution and 0.954 for the Kalai-Smorodinsky solution. The results of the proposed study provide a better insight into the various aspects of energy sharing algorithms and will help improve the utilization of green energy.
Keywords: microgrid; game theory; distributed generation; energy trading; bargaining game.
A novel policy to tackle life span reassessment of existing bulk and thin film photovoltaic materials
by Manisha Sheoran, Pancham Kumar, Susheela Sharma
Abstract: With growing planetary demands of clean energy, the solar photovoltaic system electricity generation has become mandatory in todays world. At the same time when we look towards photovoltaic waste volume in India, it is estimated to burst forth to 200, 000 by 2030 and around 1.8 million tons by 2050.Therefore there is a dire need to scale up the PV recycle method from lab to full-fledged industry. Most of the developed countries such as China, UK, Japan etc. have ensued their PV scarp management policies but in context to Indian prospective it is yet to be established. The paper focuses towards the effective remedy of the environmental and socio-economic impact arising during the life span fulfillment of c-Si, CdTe, CdS, CIS. Over here a sustainable novel policy framework is put forward to potentially tackle the above mentioned problem which is still to be adopted by Indian government for further implementation.
Keywords: Life span reassessment; Photovoltaic System; Policy; Environmental impact; Socio-economic impact.
Bio-oil Production from Agricultural Crop Residues - A Review
by Arjun Sanjay Paul, N.L. Panwar
Abstract: India generates approximately 500 million tons of agricultural crop residues per year. This crop residue (waste) can be converted into fuel by using thermo-chemical and bio-chemical conversion routes. Thermo-chemical conversion routes mainly include gasification, pyrolysis, and liquefaction. In recent years, the pyrolysis technology for the production of bio-oil is gaining attention globally, due to its simple and efficient conversion techniques. This paper provides the updated review of bio-oil production mainly from agricultural crop residues and focuses on the different bio-oil production techniques such as fast pyrolysis and hydrothermal liquefaction; the reactor used for bio-oil production, properties, and application of bio-oil. The bio-oil produced from agricultural residues has a heating value of between 17-21 MJ/kg, exactly half of the diesel fuel. The properties of bio-oil showed the potential ability to be used as fuel in many applications such as boiler, furnaces, and diesel engines.
Keywords: Bio-oil; Crop residues; Fluidized bed reactor; Fast pyrolysis; Hydrothermal liquefaction.
Research Advancements and Challenges in the Design and Fabrication of Glass to Metal Seals for Solar Receiver Tube Applications
by Vinod Kumar Verma
Abstract: Glass to metal joints has a vast field of application due to their distinct properties in terms of electric conductivity, thermal conductivity, transparency, emissivity, reflectivity, Coefficient of Thermal Expansion (CTE), density, wettability, and crystalline structure. This wide diversification in their properties makes this combination very useful in the special application like electric feed through, Biomedical, Solid Oxide Fuel Cell (SOFC) (Donald, Mallinson, Metcalfe, Gerrard, & Fernie, 2011), Incandescent electric lamps, Semiconductors diode encapsulated in glass, high vacuum and high pressure metallic chambers and enclosures, Concentrated Solar Receiver Tubes (CSRT) etc. Due to this vast diversification in the properties of glass and metal, it also becomes more challenging to make a hermetically tight seal of glass to metal for various applications. This challenge becomes bigger when such seals are subjected to a very high temperature range, ultra-high pressure or ultra-high vacuum, and also gone through repeated number of thermal cycling over a period of time, as may be in the case of CSRT. Hence how to prepare a good quality seal for such constraints, study and control of many factors are essential covered such as Seal Design, Oxidation layer thickness, Manufacturing method, temperature and time of making seal, surface roughness, and residual stresses in glass etc. that has been vigorously studied and reported in this paper.
Keywords: Glass to Metal Seal; Solar Receiver Tube; GM Seals; CSRT; Glass to Ceramic Joints.
A Review on Hybrid Nanofluid: Current Research and Sustainable Development for Turning Operation
by ANUP A. JUNANKAR, JAYANT K. PUROHIT, Nikhil V. Bhende
Abstract: Investigations on the utilization of nanofluids as a coolant for metal cutting operations have been presented very promptly and rapidly during the last few years. Despite contradiction in the presented outcomes and inadequate understanding of the phenomenon of the transfer of heat in nanofluids, it appeared as a capable coolant for metal cutting operation such as turning operation. In the extension of nanofluid research study, the eminent investigators have approached for hybrid nanofluid in recent times, which is prepared by suspending different nanoparticles with each other. The idea of utilization hybrid nanofluids is to additional enhancement of rate of heat transfer by considering benefits and drawbacks of individual nanoparticle, accredited to worthy aspect ratio, improved thermal network and synergetic influence of nanoparticles. This comprehensive review summarizes current investigations on utilization of hybrid nanofluids for turning operation. Review concluded that hybrid nanofluids are more effective than monotype of nanofluid as coolant for turning operation, accurate hybridization may help to enhancement of rate of heat transfer. But, lot of investigation is still expected in the domain of synthesis, characterization, and stability of hybrid nanofluids to overcome the effective utilization challenges.
Keywords: Hybrid nanofluid; Sustainable Development; Turning Operation; Coolant.
A review on Production processes, Performance and Emissions analysis of Hydrogen as a fuel in I.C. engines
by Monu Rajora, Dilip Sharma, Digambar Singh, Sumit Sharma, Pushpendra Kumar Sharma, Amit Jhalani, Ipsit Mishra
Abstract: The energy demand increases continuously with rapid increase in worlds population,. Continuous depletion of limited non conventional energy resources forces to move towards alternate energy solution. Hydrogen is the environment friendly most promising source to meet future energy demand. Non-toxic, non-metallic and high energy content make the hydrogen as a future generation fuel. The main sources of hydrogen production are hydro, biomass, nuclear, wind, geothermal, and solar. Hydrogen can be produced from different methods like thermal, biological, electrical, and photonic. This review article provides detailed information about the production processes of hydrogen, and performance and emissions analysis of hydrogen when it is used as a fuel in internal combustion engines. Brake thermal efficiency of the engine increases with the increase of hydrogen energy share at high and moderate loads. However, at low loads, the efficiency decreases. Carbon based emissions (HC, CO, CO2) under dual-fuel mode decreases substantially at all loads due to carbon content in the fuel. This review will help researchers to get the significant details of hydrogen production processes and its optimum utilization in internal combustion engines.
Keywords: Hydrogen; Internal combustion engines; Hydrogen Production processes; Performance analysis; Emissions analysis.
Grid Tied Inverters for Renewable Energy Systems A Review
by Sonu Kumar, Chelliah Pillai Sethuraman
Abstract: Grid tied inverters are used to feed power generated by the renewable energy sources to the local power grid. India has a total grid interactive renewable power capacity of 84.39 GW; consisting of solar 32.52 GW, wind 37.28 GW, small hydro 4.65 GW, and bio-power 9.94 GW. Solar and wind are most abundantly available in India and has various advantages over other energy sources, but combining these two intermittent sources for the purpose of exporting the generated power through grid tied inverter has many challenging issues. In this paper, various literatures, standards and patents are reviewed to understand the function of grid tied inverters, power quality, islanding detection, overvoltage protection and safety issues. This review can help the readers in understanding the basics of the grid tied inverters, and also provide information on selecting the suitable inverters for renewable energy applications.
Keywords: Grid Tied Inverters and Controllers; Solar; Wind; Renewable Energy; Standards; Patents; Power Quality.
Study on physico-chemical treatment of effluents from biomass gasifier power generation system
by Sunil Narnaware, Samir Vahora
Abstract: The study aimed at a physico-chemical treatment of effluent/ wastewater generated from the wet scrubber unit of the biomass gasification based power generation system. A process consisting of coagulation and flocculation was used to improve the quality and recycling ability of the effluent (scrubbing water) for its reuse. A laboratory study determined the optimum dose of lime (CaOH2) as coagulant and alum (Al2 (SO4)318H2O) as flocculants in the proportion of 1:1 g/l of effluent which later applied in the field experiment. The field results showed that freshwater once used in the wet scrubber unit could be used for two more recirculation by giving physical settling treatment. Thereafter, the chemical treatment with a predetermined dose of lime and alum was given due to increased load of tar and solid particulate matter (SPM) in the wastewater which made possible to use the wastewater two more recirculation in the wet scrubber unit. After fifth-time use, the turbidity increased to 118.3 NTU which could not be brought down further with chemical treatment. The physico-chemical treatment improved the recycling ability of wastewater reducing the overall water requirement. The cost of chemical treatment for laboratory-grade chemicals was found ? 0.85 per litre of effluent and ? 0.10 per litre of effluent for commercial grade chemicals.
Keywords: Gasifier; syngas; effluent; tar; physico-chemical treatment.
Forest Waste to Energy in the Himalayan Region: Technical and Economic Evaluation
by Arvind Singh Bisht, N.S. Thakur
Abstract: The Himalayan subtropical pine forests spread all over the Himalayan region. Every year during the summer season, dry leaves (pine needles) fall from the trees and cover the forest area, destroying soil fertility and also cause forest fires. The energy recovery from waste biomass through gasification process is receiving renewed interest. In this present study, pine needle biomass gasification characterization along with economics of energy generation is carried out. Results indicate that a maximum of 135 kJ /mol of energy is required for the complete gasification of pine needle biomass. The energy released per kg of pine needle gasification is found to be 15.66 MJ/kg. It produces producer gas of calorific value 5.07 MJ/Nm3. These producer gas used in 100% producer gas engine generator set for electricity generation, the levelized unit cost of Electricity (LUCE) varies between 6.5 INR/kW to 14.84 INR/kW under the different financial and operating conditions.
Keywords: Energy; Biomass gasification; TGA; Pine needle; Kinetic investigation.
Recent advances in solar tunnel dryer for performance improvement in food drying process: A Review
by Ankit Agarwal, Kunj Bihari Rana, B. Tripathi
Abstract: The unexpected increase in demand and persistent shortage of fossil fuels continues the search for an alternative source of power. Solar energy is one of the sustainable and renewable sources of power that encouraged various researchers from all over the world. The production of food and its immediate consumption is the biggest problem to reduce the wastages of food. To overcome the wastage, drying is an excellent methods to preserve the food grains, fruits and vegetables. For drying, conventional drying system is sun drying which is free and renewable sources of energy. But, there are various limitations e.g. rain, dust, animals, wind and insects. The use of solar dryers can eliminate these limitations significantly and enhance the productivity of farmers towards better revenue earned. This review attempts to provide in brief the recent developments to increase the temperature of drying chamber and applications of drying technology for different foods and agricultural produce, with particular emphasis on the modifications in the dryer and process conditions. This review paper will be helpful to know about the recent trends and different useful aspects of solar tunnel dryer to the new researchers.
Keywords: Solar energy; dryer; greenhouse; thermal performance; tunnel dryer.
A review of different configuration of hybrid energy systems with case study analysis
by Uttara Das, Sarbani Mandal, Somudeep Bhattacharjee, Champa Nandi
Abstract: Increasing energy demand in worldwide is directly related to the power generation process. Carbon emissions cum greenhouse gas emissions have direct contact with global warming and climate change. Energy generation from conventional power plants is the cause of a huge amount of environmental pollution. Different renewable energy sources are a great option to fulfil all the criteria as these are cost-effective, environment-friendly and abundantly found in nature. But renewable energy sources are varied in nature and for overcoming this problem; renewable energy-based hybrid system is a better solution. This paper reviews various challenges and recent developments in the area of the hybrid renewable energy system and also reviewing a backup system like pumped hydro energy storage system (PHES). We also discuss some real-world case studies of renewable energy-based hybrid power plants adopted in various parts of the world. This paper concludes with suggestions for future research opportunities in this field.
Keywords: Renewable energy; Hybrid system; Greenhouse gas reduction; cost-reduction; backup system; PHES.
Technical feasibility study and optimization analysis on solar-biomass based pumped storage hydropower plant
by Somudeep Bhattacharjee, Champa Nandi
Abstract: The potential of hydroelectric plants in north-eastern region is very much promising for supplying electricity. But the reservoirs of hydroelectric plants are facing water shortage during the lean season, which results in a very low power generation. Gumti hydroelectric plant generates power to diminish the power crisis of Tripura but it remains inoperative during the lean season due to the shortage of water. Therefore, this study proposes advancement to Gumti hydroelectric plant in Tripura by designing a hybrid energy system using renewable energy sources to supply a dependable, continuous and economical power supply. This study includes optimization analysis by utilizing real-time data of renewable energy sources, which help us to understand the extent of power generation and its cost of energy. The results of this study indicate that a hybrid system is a viable option as compared to a single hydroelectric plant in maintaining the continuity of power supply.
Keywords: Climate Change; Solar Power; Hydro Power; Bio power; Pumped Storage System; Hybrid Energy System; Optimization.
Financial Feasibility of Solar PV Lanterns for Households of a Remote Village Cluster without Access to Electricity
by Devendra Kumar Doda, Mahesh Bundele, Amit Shrivastava, Tara Chandra Kandpal
Abstract: In this study, the financial feasibility assessment of adopting state-of-the- art designs of solar PV lanterns by the households of a remote village cluster in the state of Rajasthan, India has been undertaken. LED based solar PV lanterns are expected to save kerosene and meet their lighting energy demand. Based on a survey of the village cluster, the household level requirement of solar PV lanterns (three numbers each with a 3W LED lamp), annual kerosene saving (approximately 100 liters) and the values of several measures of financial performance include Discounted Payback Period (merely 4.7 years), Net Present Value (Rs. 11263/-) and Benefit to Cost Ratio (2.37) has been estimated. From a financial perspective an investment in the solar PV lanterns by a household appears to be quite attractive and may be explored by Energy Service Companies. The results of detailed calculation undertaken have been presented in the paper and discussed.
Keywords: Environmental emissions; Financial Feasibility analysis; Lighting energy demand; Payback period; Solar PV lantern; Sustainability.
A building bio-climatic design tool incorporating passive strategies in residential dwellings design of composite climate of India
by Sanjay Kumar, Anuj Mathur, K.B. Rana, Chandan Kumar
Abstract: The objective of the present work is to assess the potential of different passive design strategies using the bio-climatic approach in residential spaces under diverse climatic conditions across the composite climate in India. For this purpose, a modified building bio-climatic design chart based on composite climate specific adaptive thermal comfort zone (CZ) has been used. The climates of four major cities namely Delhi, Jaipur, Lucknow, and Hyderabad having geographical and climatic variation within composite climate, have been selected for bio-climatic analysis using Typical Meteorological Year (TMY) data. The results from the bio-climatic analysis showed that comfort can vary 30% to 60% of the total time during summer and 43% to 70% of the total time during the winter season, respectively. During warmer half of the year (MarchOctober) natural ventilation, sun shading, and direct evaporative cooling proved to be the better choice for passive cooling. For hot and humid areas, like Hyderabad in composite climate, natural ventilation, shading and direct evaporative cooling showed more potential for indoor comfort. However, passive solar heating only provides the noticeable result for improving indoor comfort conditions during the colder half of the year (NovemberFebruary) for all selected cities. It was also noted that relying entirely on these passive design strategies to maintain thermal comfort is not possible and conventional cooling and heating is required for a considerable time. Finally, this study put forward a guideline matrix for the use of passive design schemes in buildings for composite climate of India.
Keywords: Bio-climatic design chart; Adaptive comfort zone; Passive design; Composite climate; India;.
Enhancement of Quality of Polypropylene by Optimization of Injection Molding Parameters with Genetic Algorithm
by Deepak Kumar, G.S. Dangayach, P.N. Rao
Abstract: Plastic injection molding (PIM) represents one of the most vital processes in the mass production of precise plastic parts with intricate geometries. Polypropylene (PP) is widely used material related to plastic parts for automobile and packaging industry. It was observed that thermal shrinkage and warpage in plastic parts are most prominent defects and affects the quality of plastic parts. In this paper, a methodology has been exhibited for reducing the thermal shrinkage and warpage with the maximization of impact strength (IS) of virgin Polypropylene (PP). To obtain the optimum values of Injection molding parameters Taguchi orthogonal array (OA) was used. Overall, six parameters were chosen for the experiment. The linear graph was utilized to know the effectiveness and interactions of the parameters. Thus, with Taguchi method minimum thermal shrinkage 4.67 %, minimum warpage 1.8 mm and maximum impact strength 56.7 J/m was obtained in PP specimens. With this methodology, prediction equations and mathematical models for thermal shrinkage, warpage and IS of PP were developed successfully which are useful for industrial applications. With multi objective genetic algorithm, these mathematical models were optimized.
Keywords: Plastic injection molding; Taguchi’s orthogonal array; ANOVA; thermal shrinkage; warpage; impact strength; Polypropylene; multi objective genetic algorithm (MOGA).
Analysis of Biochar from Carbonization of Wheat Straw using Continuous Auger Reactor
by Ashish Pawar, N.L. Panwar
Abstract: The agricultural residue is considered as one of the promising organic biomass materials for getting energy-rich products (such as biochar, bio-oil, and syngas, etc.) via. thermochemical conversion route. In current study the biochar was produced from wheat straw using continuous auger reactor and analysis of produced biochar in terms of product yield, energy yield, and its physicochemical composition. Carbonization of wheat straw was carried out in a continuous auger reactor at four different temperatures i.e., 350, 400, 450, 500 oC by keeping a 5 min of residence time respectively. The maximum mass and energy yield of wheat straw biochar was recorded at 400 oC. The wheat straw to biochar conversion efficiency in a continuous auger reactor was about 30%. The higher heating value (HHV) of produced biochar was varied from 20-23 MJ/kg, so it indicates biochar can efficiently use in thermal applications. The physicochemical characterization of biochar produced at 400 oC was also carried out at bioenergy laboratory. The obtained biochar showed higher carbon content of 70 %, H/C and O/C ratio were found to be 0.022 and 0.29, respectively.
Keywords: Wheat straw; Energy; Biochar; Carbonization; Auger reactor; Agro waste.
Special Issue on: ICONRER-2019 Smart Use of Resources and Strategies for Sustainable Development
Comparative Study of MPPT Techniques for Solar PV Based System
by Ram Singh Yadav, Dheeraj Dhaked, Ashish Jaiswal
Abstract: Abstract: Electrical power generated from solar power plant is growing enormously due to increasing usage of green and environmentally friendly energy sources and insufficiency of traditional fuels like coal reservoirs, gas and fossil fuels etc. the relevance of renewable energy source (RES) like solar photo voltaic (PV) and wind energy are rapidly growing. RES is helpful to reduce the environment pollution. Due to intermittent nature of RES, the parametric control is needed in Distributed Generation (DG). In projected study, solar PV is used for generation of electrical power. PV module is used for system designing and coupled with system load through DC/DC power converters. The perturb and observe (P&O) and variable step size incremental conductance (VSS-IC) based optimization techniques are utilized with buck- boost converters (DC/DC converter) to examine different outcomes. This study shows comparative investigation of the maximum power point tracking (MPPT) methods with VSS-IC and P&O for Solar PV system. The parameters used for investigation are output power and voltage from DC/DC converters. The arrangement is considered in MATLAB/SIMULINK software. On the basis of investigation carried out, the outcomes for different temperature and irradiation with VSS-IC controller, P&O and without controller with buck-boost converter are shown in results.
Keywords: Solar PV, MPPT Technique, Optimization, P&O, DC-DC converter.
Selection of Phase Change Material for Thermal Energy Storage Integrated with Solar Powered Vapor Absorption System Using MADM Tools
by Dinesh Kumar Sharma, Dilip Sharma, Ahmed Hamza H. Ali
Abstract: In the present study, 13 phase change materials (PCMs) are first scrutinized from the commercially available PCMs for temperature operating range from 90 to 120
Keywords: phase change material; multi attribute decision making; solar vapor absorption system; analytical hierarchy process; multi objective decision making.