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Showing 212 results for Efficiency


Volume 0, Issue 0 (1-2024)
Abstract

This study investigated the effects of irrigation strategies including sustained deficit irrigation (SDI) and partial root-zone drying (PRD) on the growth, physiology, and photosynthesis of strawberry plants in order to maximize crop productivity while maintaining water resources. This experiment has four irrigation strategies (FI: control (full irrigation volume), PRD1 (full irrigation volume), PRD2 (50% of FI), and SDI (50% of FI) and two fertilizer strengths (EC1 and EC2) with four replicates per treatment. Gas exchange, leaf chlorophyll index, stomatal conductance (gs), and maximum quantum efficiency of PSII photochemistry (F'v/F'm) were assessed on three occasions throughout the experimental duration in order to monitor the impact of different irrigation strategies on photosynthesis. Yield water use efficiency, as well as TSS (total soluble solids) and TA (total titratable acidity), two fruit quality-related parameters, were also measured. In the final stage, PRD2-EC2 photosystem II efficiency was 9% higher than SDI-EC2. Also, the PRD strategy effectively influenced and regulated the adjustment of stomatal conductance (gs). In diluted fertilizer (EC2), yield WUE of PRD1 and SDI performed 15% and 30.7% lower than FI-EC2. However, PRD2-EC2 treatment increased 72.5% more than the control. Our observations of leaf and fruit deficiencies showed that the PRD strategy had long-term benefits for the plant and reduced water consumption. However, to establish a sustainable irrigation strategy, the nutrient solution must be adjusted to control growth and photosynthesis attributes.


Volume 1, Issue 4 (12-2013)
Abstract

An 84-day feeding trial was carried out onfingerling (4.44 ± 0.06 g) rainbow trout (Oncorhynchusmykiss, Walbaum, 1792) to evaluate the effect of dietary supplementation with a commercial prebiotic GroBiotic®-A (G-A) on the growth, feed efficiency, haematology and immunlogical parameters. Ttreatments containing various inclusions of G-A (0 %, 0.5 %, 1.0 %, 1.5 %, 2.0 %, 2.5 %, and 3.0 %) were added to a commercial fish dietand were fed twice daily at 2-6 % of body weight. The highest weight gain (WG), specific growth rate (SGR) and average daily gain (ADG) were obtained in fish fed the diet containing 2.5 % G-A followed by 3.0 % inclusion (P<0.05). The highest feed efficiency (FE), protein efficiency ratio (PER) and net protein utilization (NPU) were also recorded in the 2.5 % G-A inclusion (P<0.05). Survival was significantly higher (P<0.05) in fish fed with 2 % and 2.5 % G-Asupplement (P<0.05). Although higher Hb, haematocrit, RBC, WBC, MCH, MCHC, MCV, lymphocytes, and neutrophils were observed at all  G-A supplemented diets, the differences among themwerenot significant (P>0.05). On the other hand,significantly higher differencee (P<0.05) in lysozyme and immunoglobulin (IgM) concentrations wereobserved in 2.5% G-A inclusion. The results of this study indicated that 2.5 % G-A inclusionhad a better performance on growth and haematoimmunological parameters in rainbow trout fingerling.

Volume 1, Issue 4 (12-2023)
Abstract

Today, carbon dioxide emission is one of the concerns of all countries in the world, so in this paper, we examine the effect of export quality, energy efficiency, and economic complexity on CO2 emissions per capita during the period of 1990 to 2014 in emerging economies. For this purpose, first, energy efficiency is calculated using mathematical programming methods (DEA). Then, the effect of export quality, energy efficiency, and economic complexity on per capita carbon dioxide emissions in the panel of emerging economies is investigated using panel quantile regression. The energy efficiency results show that the average energy efficiency of the studied countries had been increasing from 1990 to 2014. The lowest efficiency score among the studied countries is related to China. The results of quantile regression indicate that the export quality and consumption per capita of fossil fuels have a positive and significant effect on CO2 emissions per capita in all quantiles. The results also show that the coefficient increases by moving in the level of quantiles, so that, the highest effect coefficient of export quality on CO2 emission is related to the quantile 90th and about 0.874. Energy efficiency has a negative and significant effect in all quantiles except 90th, and the highest coefficient of influence (0.133) is related to quantile 10th. The increase in economic complexity increases the co2 emissions in all quantiles except 10th, and the highest coefficient (about 0.487) is related to quantile 90th. 

Volume 2, Issue 3 (11-2012)
Abstract

Data envelopment analysis (DEA) has proven to be very useful in evaluating relative efficiencies of decision-making units (DMUs) with multiple outputs and multiple inputs. The conventional form of data envelopment analysis evaluates performances of decision-making units only from the optimistic point of view. In other words, it chooses a set of the most favorable weights for each decision-making unit. There is another approach that measures the efficiency of a decision-making unit from the pessimistic point of view. This approach chooses a set of the most unfavorable weights for evaluation of each decision-making unit. In this paper, we propose to integrate both efficiencies in the form of an interval in order to measure the overall performance of a decision-making unit. The proposed Data Envelopment Analysis Models for evaluation of efficiencies are called bounded data envelopment analysis models. The proposed approach will be compared using a numerical example. Another example about assessment of burden-sharing among members of the North Atlantic Treaty Organization (NATO) will be presented to illustrate the advantages, simplicity, and utility of this approach in real-life situations.  

Volume 2, Issue 3 (11-2012)
Abstract

There are several approaches for increasing the competitive power of an organization. However, in some cases, some of the approaches are contradictory. Improving efficiency and productivity is one of the best approaches to solve these conflicts. In this research, we have measured the efficiency of five active iron mines during 2008 - 2011, using Data Envelopment Analysis (DEA) method and the efficient and inefficient units were determined. Due to the limited number of studied mines compared with the total amount of inputs and outputs, the discrimination could happen. Thus, we have used Anderson-Peterson (AP) approaches as a complementary method for DEA classic models, in order to determine productive units' final ranking. Based on the results obtained, Mishduvan mine has the highest rank and the highest amount of efficiency during 2009 - 2011.

Volume 2, Issue 3 (9-2014)
Abstract

The objectives for this study were first to understand and estimate energy consumption in each stage of production and processing of milk using regional data and second, suggesting improvement opportunities. A cradle to gate assessment of market milk was performed by separating the system into three stages: agronomy, animal farm and processing plant. Data were collected from multiple sources e.g. questionnaire, published papers, national and international databases, and the processing plant database. Throughout the study, ISO framework and International Dairy Federation guideline on life cycle assessment were used. The functional unit (FU) was one liter of pasteurized milk packaged in plastic pouch at the processing plant gate. The average energy demand for producing 1 kg of fat-protein corrected milk at farm-gate was 10.8 MJ, although for the final packaged milk, it was 12.5MJ. Main stages in overall energy use of FU were agronomy 68 %, animal farm 19 % and processing plant 13%. The average energy use for raw milk production was 2-5 times higher than previous European reports. To enhance efficiency in this sector, we need to assess other regions’ potentials for feed and milk production and then to focus on agronomy stage for lower energy use by optimization of irrigation, or even importing energy intensive feed such as barley and alfalfa from other countries.

Volume 2, Issue 4 (3-2014)
Abstract

Processing efficiency of rainbow trout, amounts of by-products and their nutritional value as well as some correlations between whole fish weight and products yield were evaluated. Results showed that efficiency decreased up to 87.56 ± 3.43% for gutted fish and it reached up to 56.69 ± 3.26% and 45.36 ± 2.37% for skined on and skinless fillets, respectively. The highest amounts of by-product were related to head and viscera which were 15.52 ± 2.00% and 12.62 ± 2.61% of body weight, respectively. A significant negative correlation was found between fish weight and head weight percentage (P<0.01). Also, the yield of headed and gutted product increased significantly by increase in fish weight (P<0.01). Among by-products, viscera and head were the richest sources of fat (17.4 and 13.0 % of wet weight) and skin contained the highest amount of protein (24.1% of wet weight). Moreover, a significant presence of the most important and health benficial omega-3 fatty acids was detected in both head and viscera. Viscera and bone were also found as rich source of iron mineral.

Volume 3, Issue 1 (6-2014)
Abstract

The probiotic effects of Saccharomyces cerevisiae and Aspergillus niger on the feeding efficiency, body composition, ammonia excretion, blood serum enzymes and the intestinal microbiota of juvenile beluga, Huso huso was investigated. The fish (31.8±2.81g) were randomly allocated into 12 oval tanks at a density of 30 individuals per tank with three replicates for each treatment,. The fish were fed either a basal diet (as control) or the diet supplemented with S. cerevisiae and A. niger (2×106, 4×106 and 6×106 cells g-1) for 8 weeks. The results indicated that the probiotic supplemented diet at 6×106 (cells g-1) significantly improved FCR and other nutritional indicators compared to the control treatment (p<0.05). Significant improvements (p<0.05) were also observed in ammonia excretion and blood serum enzymes between treatments. Total viable fungus and Lactobacillus spp. count were significantly improved in treatment compared to control (p<0.05). These results indicated that S. cerevisiae and A. niger improved feeding performance and blood serum enzymes of beluga.

Volume 3, Issue 3 (12-2014)
Abstract

The effect of a probiotic containing five species of bacilli at four levels of 0 (control), 1×106CFU/ml (T1), 1×107 CFU/ml (T 2) and 1×108CFU/ml (T 3) per 100g of feed on the growth performances, resistance and survival of rainbow trout fry, Oncorhynchus mykiss (463±32 mg) were compared in a  60-days feeding trial. Growth parameters, such as ADG, SGR, RGR and TGC, were significantly enhanced (p<0.05) by the probiotic at all levels, and the performance in T2 was significantly better than T1. The fish under the probiotic treatments also showed higher resistance (p<0.05) to such Environmental stresses as alkaline pH, heat and ammonia (p<0.05). No significant difference in tolerance to acidic pH stress was observed between the control and treatments. In conclusion, the probiotic bacillus highly increased the growth performances, feeding efficiency, resistance and survival in rainbow trout fry.

Volume 3, Issue 4 (2-2015)
Abstract

The effect of two salinity concentrations (35 and 40 ‰) on the daily feeding and burrowing activities of the sea cucumber, Holothuria parva was investigated, using the nutritional parameters (intestinal  indices, organic materials, and the absorption efficiency). Although no significant difference between the initial and final sections of the intestinal gut of sea cucumbers in two saline conditions was found, the maximum level of intestinal indices, organic material and absorption efficiency was associated with the 40‰ salinity. The survey results displayed that sea cucumber had better feeding activity in 40‰ than 35‰ salinity.  

Volume 4, Issue 2 (9-2023)
Abstract

Aims: Efficiency as a cultural index can be defined as the comfort resulting from the proper arrangement of components and the connection point between form and function; which plays an important role in adding quality to the space. Such an attitude to design; It is an attempt to obtain a model of valuable previous architecture to measure sustainability and discover the grammar of space in order to create works for the future of architecture.
Methods: The current research is a kind of documentary research, based on the use of data of valuable models of the past, which, by adopting a descriptive-analytical approach, analyzes the concept of efficiency in the structure of function and form in native Qajar houses of Isfahan.
Findings: Most of the massing has been done in the north (public spaces), west (service spaces), south (private spaces) and east (service spaces) fronts, respectively. Also, the data obtained from Ecotect software shows that the best direction in Isfahan city is between 17.5 degrees southwest and 22.5 degrees southeast. However, the frequency of Isfahan Orientation in the native Qajar houses of Isfahan is very low, and the emphasis is on the orientation in the north-south direction, and the southeast or southwest of it has not been given much attention.
Conclusion: The configuration of the space, the amount of received energy and the visual communication of the environment (sight) are among the indicators that affect the efficiency, which is understood by the way of massing, spatial relations and spatial proportions.

Volume 4, Issue 4 (12-2015)
Abstract

Control of stored-product insect by gamma radiation could be enhanced by other possible techniques such as essential oils as effective alternatives to chemical insecticides. In this study, the efficiency of gamma radiation combined with Perovskia atriplicifolia (Benth) was verified to assess their enhanced antifeedant effect against the Tribolium castaneum (Herbst). Flour disc bioassay was employed to assess the nutritional indices, such as relative growth rate (RGR), relative consumption rate (RCR), efficiency of conversion ingested food (ECI) and feeding deterrence index (FDI). The results showed that irradiation, essential oil and combination of both of them significantly reduced RGR, RCR and ECI in treated larvae and adults. As irradiation at 100 Gy reduced RGR of the larvae and adults from 0.0884 and 0.0366 to 0.0596 and 0.0332 mg/mg/day respectively, when combined with doses of P. atriplicifolia essential oil, the reduction reached to 0.051 - 0.388 and 0.01- 0.224 mg/mg/day respectively. The reduction rates in larvae were even greater when combination of irradiation and EO treatments were used. The results showed a significant increase in the feeding deterrence due to irradiation, essential oil and specially their combination. Therefore, findings led to a conclusion that irradiation can enhance antifeedant activity of essential oils.

Volume 6, Issue 1 (7-2016)
Abstract

Introduction: Based on current estimations of different organizations, half of the world’s population live in cities, and these cities are the main consumers of energy. Cities have grand contribution in energy production of the world (around %60 to %80) and they have such enormous contribution in the emission of CO2. Energy is at the heart of the most critical economic, environmental and developmental issues facing the world today. Energy is essential to the delivery of urban services, and its role can be consid-ered vital at many stagesin the urban design process. This research begins with the planning and layout of a new cityand goes through to the socioeconomic structure of the city and its activities and the choiceof energy carriers and technologies used to meet the city’s energy demands. In recent years, there has been a surge of interest in urban climate and energy issues. LiteratureReview:Based on theories and history of energy consumption levels in different countries and with the consideration of sustainable development in the world, protection of energy resources became important and along continuing years, different approaches like smart growth, compact development, etc. have been introduced which shows the importance of this issue. Urban planning and design determines a city’s spatial, physical and managerial structure and influences directly and indirectly the energy consumption. Energy modeling in city scale is an ideal tool for studying energy consumption and reducing production of greenhouse gases in urban planning level. Models of urban efficiency evaluation in city scale is based on building, transport, etc. criterions and their great potential for consuming energy and producing greenhouse gases, can be proper guidelines for reducing energy consumption and in-creasing energy efficiency (EE). With regards to population growth and rapid urbanization, It seems es-sential to evaluate energy consumption and for improving its efficiency with different strategies. With regards to these issues, EE, either for protection of energy resources and optimum utilization of them, or for opposition with climate change and their pollutions, are issues which have importance in both nation-al and international dimensions. So, many actions have been accomplished which concentrate on two main issues: sustainable development and opposition with climate change. There are few studies about these issues, for example World Bank has worked in a few case studies such as Gaziantep in Turkey.In Iran, also based on done census in recent years, we have evolved in ur-banization through the increase of city›s count and immigration of villagers. There is also limited case studies in Iran, about the energy efficiency assessment in small scales, such as the neighborhood and building. So, nowadays, necessity of energy efficiency evaluation is important because of irregular energy consumption through optimized actions of urban planning which can reduce a city’s dependence on fos-sil energies and reduce costs and release financial resources for improvement of city services and social-economic advantages. Methodology: The purpose of this study is to determine the relationship between urban planning and energy efficiency, to present related approaches to this issue and to survey energy efficiency evaluation models with an emphasis to urban scale. Depending on the scale studied, models with different scales can be used to evaluate energy efficiency. Some models are used to study the energy efficiency in the scale of cities and others in lowers scales of a city’s divisions, such as districts and neighborhoods. Through studying EE models, we can identify their effective factors and existing barriers, as well as their performances. After considering the theoretical elements in evaluating the EE in city planning while fo-cusing on identifying different models and approaches to evaluate energy efficiency, two models in two levels have been chosen in this research: Firstly, TRACE model was chosen to evaluate the amount of energy consumption with different indices and criteria in the whole city of Tehran and the required sug-gestions were made for EE to be increased.TRACE is a decision-support system designed to help cities quickly identify and harness EE opportunities. It targets underperforming sectors, evaluates improvement and cost-saving potential,and helps prioritize actions for EE interventions. TRACE focuses on the munici-pal sectors with the highest energy use: passenger transport, municipal buildings, water and wastewater, public lighting and solid waste. Then, LEED model was chosen in the second level to evaluate energy efficiency more accurately in the districts of Tehran, and the sample neighborhood was Zahirabad in District 20 of Tehran which was studied with different indexes so that the EE in this area could be evaluated. The LEED is based on existing proven technology that drives market strength and credibility through the industry-wide development of LEED products. LEED is an initiative designed to actively promote the transformation of the mainstream towards more sustainable practices. Results:Results show that energy consumption evaluation can identify the High-power indicators and have an important role in reducing consuming energy of cities. In this study, in the initial level, Trace Model, based on comparison with other world cities, which has been included in presupposition of mod-el, and determination of their priority, building and transport indicators have been estimated as the most energy consumer parts of Tehran; And in the second level, in order to evaluate energy efficiency in neighborhood scale, has been done with LEED model which concentrates on most energy consuming indicators in first level -building and transport-. The score of neighborhood evaluation with LEED model is approximately acceptable based on this model and with regards to chosen criterions energy efficiency in neighborhood is in middle level and with changing certain situations we can increase EE in neighborhood. The survey of energy efficiency in one of the neighborhoods can provide a framework for evaluating other neighborhoods of Tehran in future studies and finally estimating EE in city level. Paying respect to time limitations, this neighborhood has been chosen just as a case, in order to use this model for other neighborhoods of Tehran and to recognize legal frameworks and development plans, policies and strate-gies for reducing energy consumption in different levels. Discussion and Conclusion: Research findings show that construction and transportation are the two most effective factors in the amount of energy consumption and efficiency. Resulting strategies from this study -based on tools and methods of energy efficiency evaluation- for reducing energy consumption and increasing energy efficiency include: promotion of mixed land-use, augmentation of density and compaction, development of public transportation, management and pricing parking, augmentation of pedestrian and bicycle accessibility and changing of energy consumption patterns at home, building and infrastructure parts, etc. Moreover, consideration of essentials in using reproducible energies in plan-ning can improve the utilization of these energies and increase energy efficiency. It ought to be said that in order to respond to the energy efficiency challenge in cities, it is important to choose a particular method with regards to native situations and city scale. With presenting proper strategies and changing in case studies, we can adjust energy consumption and go toward energy efficiency and a sustainable de-velopment. So, according to the results from analysis and proposed recommendations and strategies for improving energy efficiency in two scales, we can increase energy efficiency with setting policies and taking action.

Volume 6, Issue 2 (5-2015)
Abstract

The purpose of this research was to study the efficiency of general Arabic language teaching program in Kerman high schools based on the students’ and teachers’ viewpoints. This study is an applied quantitative method research. The research instruments are two researcher-made questionnaires for measuring the teachers’ and students’ viewpoints. The population involves all male and female Arabic teachers of Kerman city, as well as male and female Mathematics and Science junior high school students of all public high schools of Kerman city. The research sample was selected through stratified random sampling method, and amounted to 30 female Arabic teachers, 30 male Arabic teachers and 236 students. The findings revealed that  Arabic language teaching goal is not consistent with the learners’ and society’s needs; Arabic textbooks’ content does not meet the content selection standards set in curriculum planning; Arabic teachers are not well prepared for Arabic language teaching; Arabic curriculum goals are not met; students’ proficiency in Arabic language skills is disappointing; students’ interest in Arabic language and learning, is moderately low; and finally, students’ acquaintance with Arabic language learning strategies is low. Accordingly, we can conclude that the increase in Arabic language teaching efficiency in schools needs more efforts to prepare the society with positive attitude towards Arabic language and Arab people, and also to change the educational approach to Arabic language teaching/learning in our school system.

Volume 6, Issue 3 (11-2016)
Abstract

Energy efficiency and comfort consideration in building, contribute to significant energy saving and improvement of spatial quality. According to the importance of energy issues and lack of researches on energy use in educational buildings, climatic variation in the country and huge amount of energy consumption in educational buildings, the need of redefinition environmental design criteria is essential.
The main purpose of this article is to assess the influence of different design variables on comfort condition and energy consumption in the hot-Arid climate of Tehran. Most of the literature concerned with energy performance of school buildings is focused on using saving methods such as utilization of solar energy, constructional issues such as thermal insulation, infiltration, thermal mass, building materials, sun shadings and HVAC performance while assuring thermal comfort and indoor air quality of the building. However, the topic of energy performance and comfort condition of schools located in Iran’s climatic conditions has not been explored.
Nowadays, the subject of energy and optimizing energy consumption in different buildings and different societies is of great importance. On the other hand, energy experts claim that in designing educational buildings, natural energy resources should be used most. This subject is related to the energy consumption of schools. Furthermore, the positive effect of thermal and visual comfort on the quality of students’ education has been confirmed. Educational buildings generally are spaces with different functions.
However, classrooms not only have a central role, but also cover a great part of the school surface. Classrooms are the most fundamental and important units of the educational buildings in terms of energy consumption and thermal comfort. Students spend most of their time in the classrooms. Classrooms are more important, given the relative congestion in comparison with other educational spaces. Due to this fact, proper ventilation is considered necessary. Furthermore, students’ presence as latent thermal energy sources needs special attention in hot seasons. On the other hand, the same thermal sources can play an effective role in creating the comfortable conditions. Therefore, according to the difference of using pattern of these places and their higher internal heat gain, energy saving patterns in designing office and residential buildings cannot meet the needs of designing these buildings.
Methodology
This research using simulation method is looking forward to realize the influence of different physical variables on energy consumption in educational buildings in Tehran’s climate; the different circumstances that were resumed by diverse variables were assayed. this process took place with the help of E quest energy simulating software and during this process in two separate parts, the independent effect of each variable and the simultaneous influence of applying diverse variables on energy consumption were simulated and its results were compared and discussed in various steps.to enumerate the most essential effective parameters in determining the amount of energy consumption in educational building in Tehran’s climate, we can point out the infiltration rate, heat isolating of the building roof and windows dimension.
To understand the range of influence of each variable on the comfort condition and energy consumption in the classroom, the difference between the maximum and minimum energy consumption obtained for each of the evaluated variables was considered. This difference represents the potential savings that can be achieved by improving a variable within the considered range of values. In this work, the four main orientations were analyzed.to observer the influence of design parameters on energy consumption, a base case classroom was designed and then the absolute and simultaneous effects of different parameters were assessed. The base-case was a common classroom to where all changes were applied and examined. Based on the similar studies, the recommended value for each design variable was determined to achieve a high
performance classroom. The fixed parameters of the classroom were its size and height. The thermostat of the heating system was set at 21.1 C while the thermostat of the cooling system was set at 24 C, due to the dissimilarity in the children’s clothing in different seasons. The ventilation system provides a minimum of 4.5 air changes-per-hour (ach) when the classroom is occupied. When there were no children in theclassroom, the ventilation rate will reduce to save energy and the lighting level on the children’s tables was set at a minimum of 300 lux.
Results
The results indicate that by reducing the infiltration rate of the classroom from 4.5 ACH to 0.75 ACH, an energy saving of about 65 KWH/m2.y will achieved. The airtightness of a classroom depends on windows and doors type, quality, and materials as well as on the quality of the construction process. For obtaining infiltration rate of about 0.75 ACH, designers and contractors should give more attention to the quality control of materials and construction and energy performance of the windows and the doors. Meanwhile according to the high amount of sun radiation during the year, roof heat insulation with a 6cm polyurethane layer would reduce the energy consumption by 40 KWH / m2.y in comparison with a roof without any heat insulation. Since the windows have a significant influence on the energy consumption and performance of the classroom, In order to reduce the energy consumption, dimensions and position of the windows should be choose very carefully. It was observed that the recommended size of north and south facing windows is equal to %12 of the classrooms floor area, whilst east and west facing windows should not be exceeds from %10 of the classroom area. If the windows size exceed from %12 of floor area, the glare effect would make visual discomfort for the students. In the simulation process, three types of light control features were evaluated. The results show that with the aid of smart lighting control system, the required electrical energy for lighting would reduce 34 KWH / m2.y. And finally the types of glazing have an important role in energy consumption of the classroom. It is observed that high performance was achieved when using lowemissivity
glazing to reduce cooling loads and encourage daylight in classroom. Double glazed windows shows acceptable performance as well, in all directions compared to other alternatives.
Discussion and Conclusion
After analyzing the absolute effect of each parameters on energy consumption and comfort condition in the classroom, the cumulative effect of all parameters were analyzed. It is obvious that by changing of each parameter, the effect of other parameters will be changed. In this case two combination of design variables are assessed in “set-a” and “set-b” in which the annual energy consumption of the classroom is maximum in “set- a” and minimum in “set-b”. Based on the results obtained by simulation, this can be claimed that the proper design of classrooms in hot and arid climate, like the city of Tehran can reduce the amount of energy required for cooling, heating, ventilating and lighting systems from 232 KWH/ m2.y in “set-a” to 104 KWH/ m2.y in “set- b”. It means a %55 reduction in the classroom’s energy consumption. This statics are in conformity with the results achieved by researches in European’s green school which can reduce %55 up to %75 of heating energy consumption and 30 % up to 40 % of electrical energy consumption by using different tricks.

Volume 6, Issue 3 (11-2016)
Abstract


The energy crisis of the twentieth century, numerous crises in the developing countries of the importance and necessity of contemporary architecture in particular. Industry construction industry as one of the important and influential countries, more than ever, it has become important. The changes in the construction industry, increasing energy consumption have followed. In other words, the construction industry is one of the most important and most active in numerous industries that energy efficiency is of utmost importance. The aim of this study was to assess the design and development of indigenous energy efficiency in buildings in the city of Tehran. In other words, the operational objective of this study was to evaluate and measure the energy efficiency in buildings in Tehran and practical to develop a model to measure energy efficiency in
buildings in the city of Tehran. To perform the analysis, the quality measurement values using techniques of comparative research method is descriptive - analytical approach used logical reasoning. Finally, the review and evaluation of energy efficiency, suggestions and recommendations for improving energy efficiency evaluation method is proposed with a native look.

Volume 7, Issue 2 (4-2019)
Abstract

Aims: In the new sight of the world, water is considered a good. Hence, commodity exchanges are important matters among nations. In this regard, local and international trade of virtual water as agricultural crops is an important subject in water resources management.
Instruments and Methods: In this study, the virtual water of two main exported products (watermelon and melon) in Iran during 2003-2013. Some indicators, which are used in the water resources management, such as water use intensity and water dependency, were analyzed.
Findings: By present assessment, during this period, 218.07 MCM of water in the form of virtual water was transferred from the country to outside. By efficiency calculation, it was obtained that irrigated watermelon production had the highest efficiency.
Conclusion: The results showed that producing these products in Iran was completely hinged on the internal water resources. Additionally, in watermelon is evaluated 12 times more than melon and these results warn us to have a more precise plan for the allocation of the lands for different kind of agricultural activities.


Volume 7, Issue 4 (12-2018)
Abstract

Fish consumption in Iran is less than half the global average. While in terms of access to free waters and domestic water resources, Iran is among the countries is prone to increase fish production. The aim of this study is to measure the technical, managerial and scale efficiency of fisheries in Iran and the possibility of increasing production by increasing efficiency. The above-mentioned efficiency was measured during the years 2001 to 2011 using data envelopment analysis (DEA) and an input-oriented model. Results showed that the average technical, Managerial and scale efficiency are 0.89, 0.97 and 0.91 respectively. According to the results, the highest amount of efficiency was related to Managerial efficiency. Also, the lowest efficiency was related to technical efficiency. Thus the relevant organizations can to increase the proportion of industrial fishing with appropriate capital and the larger up fishing units simultaneously improve technical and scale efficiency. The results also revealed that in most years there are increasing returns to scale.

Mahmoud Khataei, Mohammad Reza Farzin, Ali Mousavei,
Volume 8, Issue 2 (7-2008)
Abstract

Hotels are fundamental elements of tourism industry and provide various services for tourists. Moreover, hotels development has an important impact on tourism industry development. Therefore, an understanding of hotels relative efficiency performance, over a period of time, is important for practitioners, analysts, and policymakers alike. The main objective of this paper is to measure the efficiency of the four and five stars hotels in Tehran. A Data Envelopment Analysis (DEA) is employed to investigate the technical efficiency of eight hotels using the data over the period 1380 - 1384. DEA analysis is a methodology for analyzing the relative efficiency of units having the same multiple inputs and multiple outputs. In this study, the input variables comprise employee, rooms, restaurants and land and the output variables include hotel income and occupancy rate. The results show that technical and scale efficiency scores in all periods are relatively higher but there is no a regular trend over the period under study. Since 1380 to 1384; 75, 62.5, 75, 62.5, and 50 percent of the selected hotels were respectively efficient under the constant and variable to scale assumptions. Moreover, the findings confirm that more scale efficiency (0.997) refers to 1380 and less scale efficiency (0.894) refers to 1381 and 1382. The results also show that more technical efficiency, on average, under variable to scale assumption (0.964) refers to 1380 and less technical efficiency (0.894) refers to 1384. Finally, the efficiency of the five stars hotels is more than the four stars hotels implying the priority of the five stars hotel’s development in Tehran. Overall, the findings indicate that the particular problem is mismanagement in the Tehran’s hotels. Consequently, it caused the average scale efficiency to be more than the average technical efficiency. Since management plays a vital role in the efficiency improvement of hotels, this paper suggests the improvements of managerial systems in the hotels. More specifically, education, employment and Customer Reservation Systems (CRS) are the main factors influencing the efficiency.

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