Showing 116 results for Weight
Volume 0, Issue 0 (1-2024)
Abstract
The agricultural ecosystem provides various functions and services for humans. So, investigating their role and importance in the agricultural land programming and management is one of the goals research. In this research used Common International Classification of Ecosystem Services (CICES) for the identification of the Agricultural Ecosystem Functions and Services (AEFS). Also, Multi-Criteria Decision-Making (MCDM) models used for weighting and prioritizing of the AEFS like Step wise Weight Assessment Ratio Analysis (SWARA) for calculating of their weight, and Simple Additive Weighting (SAW), Additive Ratio Assessment (ARAS), and Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) used for prioritization them. The research data extracted with field survey, random sampling and completing the Delphi questionnaire of the 40 agricultural specialist experts in the north of Iran. Also, the R2 coefficient was used to compare the AEFS prioritization models. The SWARA technique findings showed that provisioning, regulation, and cultural functions with weights of 0.0298, 0.0286 and 0.0250 have the highest weight, respectively. Also, the results indicated that the SAW model with the R2=0.90 was chosen as the prioritization appropriate model. Provisioning, regulation, and cultural functions with marginal weights of 0.6319, 0.5448, and 0.5092 were ranked the first to third priority respectively. Also, food supply, employment, genetic material supply, and educational and research services were important positive services of the agricultural ecosystem compared to other services. it is suggested that more appropriate programming and more research be done by relevant organizations for the sustainable management of agricultural ecosystems in northern Iran.
Volume 0, Issue 0 (1-2024)
Abstract
Poly- gamma- glutamic acid (γ-PGA) is a natural polymer with diverse applications across multiple industries. However, its use in agriculture is limited due to high production costs. This study aimed to optimize the cost-effective production of γ-PGA through Solid-State Fermentation (SSF) using Bacillus velezensis UTB96, evaluate the concentration and molecular weight of γ-PGA suitable for agricultural applications, particularly in strawberry cultivation, and explore the impact of γ-PGA on extending the shelf-life of strawberry fruits during cold storage. Initially, the production of γ-PGA using SSF with B. velezensis UTB96 was investigated, along with an evaluation of the influence of physicochemical factors on the molecular weight of γ-PGA. Based on the results, three different molecular weights of γ-PGA were identified: 1156.43 kDa, 734.38 kDa, and 296.55 kDa. These were selected for greenhouse trials to assess their effectiveness in controlling gray mold on strawberry plants. The results showed that by utilizing agricultural wastes, including sesame flour, wheat straw, and banana peel in SSF methodology, γ-PGA could be produced at a rate of 70 g/kg of dry weight of the culture medium. Analyzing the impact of γ-PGA on reducing gray mold revealed that this compound could enhance the plant's defense. A significant increase in the activity of ascorbate peroxidase and phenylalanine ammonia-lyase (PAL) enzymes was observed, along with the production of polyphenolic compounds such as ellagic acid. Consequently, these mechanisms improved the plant's flexibility and tolerance to the fungus, helping to maintain the quality of the fruits during cold storage.
Volume 1, Issue 0 (1-2022)
Abstract
Aims A family history of obesity, physical inactivity, and an unhealthy lifestyle was associated with an increased risk of diabetes in young individuals. Most published studies had focused on single risk factors such as BMI, Physical activity, and dietary lifestyle, while the combined effect and existence of those factors were largely neglected.
Methods This was a cross-sectional study conducted on 666 male students. Based on their family history of diabetes, their anthropometric measurements were also taken, and their BMI was calculated and categorised based on WHO standards.
Findings The results showed a significant correlation between obesity, family history, and diabetes, with a significant correlation between diabetes and obesity and also had a high positive correlation. While remaining correlations were also significant.
Conclusion The study concluded that a high proportion of students are at risk of diabetes and recommended an integrated intervention program to encourage healthy eating habits and physical activity and improve awareness.
Volume 1, Issue 1 (2-2016)
Abstract
Background: we aimed to evaluate the effect of body weight and Body Mass Index (BMI) on Bone Mineral Density (BMD) in healthy postmenopausal Iranian women. Material and Methods: Two hundred postmenopausal women (age between 51 and 69 years) who had presented to the nuclear medicine center at Shariati Hospital in Tehran, Iran between April 2012 and August 2013 were included in this cross sectional study. Of these 46 healthy women who met the study criteria constituted for evaluation. After recording weight and height of individuals, Body Mass Index (BMI) (kg/m2) was calculated as weight (kg) divided by height square (m2). Bone Mineral Density (BMD) in Femoral Neck (FN) and lumbar spine sites (L1-L4) were measured by dual-energy X-ray absorptiometry (DEXA). Results: We observed statistically significant negative correlation between BMD measurements at femoral neck and lumbar1-4 spine with age and significant positive correlation with weight and BMI. Stepwise multiple linear regression analysis showed that only weight and age, after adjustments to BMI determined lumbar1-4 spine BMD (R² = 23%) and femoral neck BMD (R² = 28.6%). Conclusions: These results suggest that the relationship between body weights and BMD is Stronger than the relationship between BMI and BMD. Therefore, in comparison with body mass index, body weight alone is a better predictor of bone mineral density.
Volume 1, Issue 2 (9-2011)
Abstract
This study explored the position of Parsian Bank's financial resources. To achieve this objective. The capital structure of Parsian Bank in a seven years period (2004 to 2010) was evaluated from the financial statements of Parsian Bank.The First to third hypotheses of this study imply to optimizing of real capital structure and cost of resources and capital adequacy ratio.
These hypotheses were evaluated by the framework to achieve optimal capital structure (in terms of capital adequacy ratio and deposits to the debt ratio and long-term deposits to total deposits) and optimized.The fourth hypothesis of this study implies that there is no correlation between capital structure and financing costs (capital costs) that was tested and confirmed by Pearson correlation coefficient. Finally, several recommendations are suggested for optimizing the capital structure of Parsian Bank and future researches.
Volume 1, Issue 2 (9-2011)
Abstract
This study explored the position of Parsian Bank's financial resources. To achieve this objective. The capital structure of Parsian Bank in a seven years period (2004 to 2010) was evaluated from the financial statements of Parsian Bank.The First to third hypotheses of this study imply to optimizing of real capital structure and cost of resources and capital adequacy ratio.
These hypotheses were evaluated by the framework to achieve optimal capital structure (in terms of capital adequacy ratio and deposits to the debt ratio and long-term deposits to total deposits) and optimized.The fourth hypothesis of this study implies that there is no correlation between capital structure and financing costs (capital costs) that was tested and confirmed by Pearson correlation coefficient. Finally, several recommendations are suggested for optimizing the capital structure of Parsian Bank and future researches.
Volume 1, Issue 3 (9-2023)
Abstract
This study focuses on determining the concentration of fluoride ions in selected hand-dug wells and investigating its health implications in Gwagwalada Area Council, Federal Capital Territory, Abuja. The necessity for this investigation arose from observed health issues, including dental and skeletal fluorosis among the residents in the area. Fifteen sampling points (well water sources) were chosen in the study area, and a total of forty-five samples (three per sampling point) were collected. The calorimetric water quality analysis method was employed to analyze these samples in the laboratory. Additionally, the Inverse Distance Weighting (IDW) interpolation method was used to generate a spatial variation map for fluoride ion concentration using ArcMap. The results indicate a concentration range of 0.122 mg/L to 1.910 mg/L across the study area. When compared with the recommendations for fluoride ion concentration in the Nigeria Industrial Standard (NIS) for drinking water (0.1 – 1.0 mg/L), approximately 67% of the sampling points (10 out of 15) fall within the recommended values, while 33% fall outside. The areas with higher fluoride ion concentrations include Dupa 1, Dupa 2, Tunga Maje 1, Tunga Maje 2, and Old Kutunku 2. The study concludes that the observed dental and skeletal fluorosis in these areas can be attributed to the consumption of water with high fluoride concentrations. Consequently, the study recommends increased attention from both local and federal authorities to provide potable water for human consumption in these areas to address the associated health challenges.
Volume 1, Issue 3 (9-2023)
Abstract
Following years of contamination, rivers may experience significant levels of heavy metal pollution. Our research aims to pinpoint hazardous areas in these rivers. In our specific case, we focus on the floodplains of the Meuse River contaminated with zinc (Zn). Elevated zinc concentrations can lead to various health issues, including anemia, rashes, vomiting, and stomach cramping. However, due to limited sample data on zinc concentrations in the Meuse River, it becomes imperative to generate missing data in unidentified regions. This study employs universal Kriging in spatial data mining to investigate and predict unknown zinc pollutants. The semivariogram serves as a valuable tool for illustrating the variability pattern of zinc. To predict concentrations in unknown regions, the model captured is interpolated using the Kriging method. Employing regression with geographic weighting allows us to observe how stimulus-response relationships change spatially. Various semivariogram models, such as Matern, exponential, and linear, are utilized in our work. Additionally, we introduce Universal Kriging and geographically weighted regression. Experimental findings indicate that: (i) the Matern model, determined by calculating the minimum error sum of squares, is the most suitable theoretical semivariogram model; and (ii) the accuracy of predictions is visually demonstrated by projecting results onto a real map.
Mohammad Sadegh Alavi-Yeganeh, Bahram Falahatkar,
Volume 2, Issue 3 (12-2013)
Abstract
Length-weight relationship, age range and fecundity of 40 specimens of the Russian sturgeon, Acipenser gueldenstaedtii, collected from two fishing stations in the southeastern Caspian Sea, were determined. Average length (TL) and weight were 129.5 cm and 12.7 kg for males and 145.8 cm and 22.15 kg for females, respectively. Absolute fecundity was 184000 in average and condition factor calculated 0/58 and 0/7 for male and females, respectively. Average age for males and females was 12.7 and 14.6 years, respectively. All these factors were lower than previous records from the Volga river estuary. Length-weight relationships results demonstrated isometric growth pattern with average slope of 2.978 and 2.822 for males and females respectively. These values were not statistically different between sexes (p> 0.05), but using this relationships for each sex separately will be useful for more reliable results especially in broodstock studies.
Mohammad Alavi-Yeganeh, Bahram Falahatkar,
Volume 3, Issue 1 (6-2014)
Abstract
Length-weight relationships and fecundity of 93 individual female Acipenser persicus broodstocks were investigated. The specimens were caught during 2001-2005 from Golestan, Mazandaran and Guilan provinces along the southern coast of the Caspian Sea. Total length and weight of each fish was measured to the nearest 1cm and 100 g, respectively. Age determination was carried out by using transects of the first ray of pectoral fin. The absolute fecundity was assessed by egg count per weight unit of all eggs existed in the body. The specimens were from 13 to 20 years old, of which the 16 years old had the highest proportion with 23.7%. Range of total length and weight were 132.5 to 211 cm and 14 to 42 kg, respectively. Mean absolute fecundity was estimated 267810 ± 92570. Total length, weight and absolute fecundity of fish increased with age in all cases, showed a significant positive correlation (p <0.01). The slope of the length-weight relationship (b) was equal to 2.745 and isometric growth pattern was determined in this species.
Volume 3, Issue 2 (6-2015)
Abstract
Aim: This study focuses on the impact of contraceptive methods on weight gain among female athletes. Clinical studies confirm that weight gain is often considered a side effect of hormonal contraceptives and many women think that an association exists; this is while, Sports Medicine and Injuries’ Studies report that this effect is still unclear. This comparative study was designed to dwell on the results of similar studies.
Method: Two groups of voluntary female athletes agreed to participate in this study. They were distributed based on the conditions proposed for this study (Group 1 took the oral contraceptive, and Group 2 practised condom) for three cycles of the ovum of the same marital lifestyle. Then they were tested based on the U.S. Federal Government’s Standard Fitness Tests for Women, and their homogeneity was calculated on the basis of age (training and chronology), the typical training program, and social condition.
Findings: Based on the research findings:
• The proposed techniques prevent pregnancy record in regulating the samples’ menstruation cycle during the experiment.
• Practising condom preserves the body weight index composition with a positive physical potential.
• Taking oral contraceptive increases the body fat with negative physical potential.
• There is a strong positive relationship between the body fat and the level of body fitness in the benefit of condom.
Conclusion: Our results are in line with the findings from similar clinical and sport medicine studies, confirming that the use of oral contraceptives increases the percentage of body fat and decreases aerobic fitness among female athletes.
Volume 3, Issue 3 (9-2014)
Abstract
No doubt, damage and losses inflicted by Callosobruchus maculatus to stored products in general and chickpea in particular can be significant. The objective of this work was to evaluate the effect of the Verbascum sinuatum powder on C. maculatus oviposition behavior in chickpea under laboratory conditions (30 °C, 60% relative humidity). Powder of Mullein plant (V. sinuatum) caused reduction in fecundity, fertility, adult emergence from seeds and chickpea weight loss depending on treatment concentration (0.1, 0.05 and 0.025 g/ ml). It reduced the number of eggs laid by the weevil at first concentration to 136 eggs, the egg hatching rate at 52.22% and adult emergence to 34.03%. The percentage of seed weight loss was reduced at all studied concentrations but not significantly different at second and third concentrations compared to control. The lowest weight loss of seeds was registered at first concentration (4.7%). V. sinuatum, according to this study, showed a significant potential to reduce the egg deposition and chickpea seed weight loss due to the chickpea beetle.
Volume 3, Issue 4 (3-2014)
Abstract
Performance evaluation is prerequisite for many domains of human resource, which precise implementation of which will result in efficiency and effectiveness of performance feedbacking, training and development, promotion of employees, human resource planning, etc. Accurate weighting of evaluation indicators alongside with considering synergy and interaction force of indicators can affect evaluation results. Also differences of different levels of an indicator importance should be considered according to its great significance. This paper tries to realistically weight indicators using Taguchi experimental design method and considering two aforementioned points. An eight-stage model is presented and performance evaluation indicators for a bank cash register are specified. A questionnaire is designed based on proposed Taguchi orthogonal tables. Experts in banking sector are asked to answer the questions of each dimension to determine the weight of indicators. Results of implementing proposed model as ANOVA table show that Taguchi experimental design method can be a proper method in weighting indicators and taking into account the amount of error factor and decisions can be made according to stability of obtained results.
Volume 6, Issue 3 (11-2016)
Abstract
Horizontal development of the cities has resulted in much destruction environmentally and economically. The building’s façade acts as a barrier between exterior and interior climatic conditions. There are various methods for improving the energy performance of the building. One of these solutions is the ventilated facades. Open joint ventilated façade (OJVF) is a group of ventilated facades in which the exterior coating material (metallic, ceramic, stone or composite) is arranged in slabs separated by open joints that enable exterior air to enter and leave the cavity all along the wall. This ventilation leads to decreasing moisture and problems of condensation and ensure the health of the wall. In addition to aesthetic and constructive reasons, the main interest in open joint ventilated facades is their ability to reduce cooling thermal loads. This is achieved by the buoyancy effect induced by solar radiation inside the ventilated cavity, where the air can enter or leave freely through the joints. The OJVF is usually classified among the “light weight” or “Advanced Integrated Facades”. They are replacing the conventional facade in many new buildings and particularly in the refurbishment of old ones.
In light weight facades, the exterior light coating material is hanged over the interior wall (insulation, perforated brick or concrete, finish) by means of a metallic-frame structure or metallic bindings, leaving an air gap. The air chamber height can be the whole building height. The main difference between the OJVF and other advanced facades is that, as a rule, the ventilated air chamber is only open to the exterior at the top and at the bottom while, in the OJVF, the exterior coating is placed in an arrangement of tiles or slabs and a series of thin gaps (joints) shaped from slab to slab.
The improved thermal performance of the OJVF under radiation conditions relies on buoyancy: The slabs of the exterior coating are heated up and produce an ascending mass flow of air (by natural convection) that enters and leaves the cavity through the joints. This flow removes part of the heat loads. This phenomenon takes also place if the openings are only at the bottom and top of the facade, but the efficiency is not as high due to the reduced flow and the higher temperatures attained at the upper section of the air gap.
The main question is the effect of the open joints on the thermal performance of the façade in the various times of the year. The main objective of this work is to investigate the thermal and fluid dynamic phenomena taking place in a typical OJVF under solar radiation, and to appoint a methodology to quantify the energy savings produced by an OJVF in contrast to a conventional facade.
The determination of the linked thermal and fluid dynamic behaviour of the flow in the open joint air gap is quite a challenge, compared to the sealed cavity or even the top and bottom ventilated facades. The inlet and outlet flow through the joints all along the facade faces the analytical methods, making compulsory the use of CFD tools to obtain a detailed model. To achieve this aim, both of the open joint and the sealed facade have been simulated in the “Fluent” software.
Two series of tests have been carried out for both OJVF and sealed cavity facade. The first ones are steady state simulations directed to understand the phenomena involved, and the second ones are quasi-steady (unsteady or transient) state simulations to compare the energy performance of both systems. For the first group, two temperature conditions were selected, representing summer (T_room=24℃, T_ext = 30℃) and winter (T_room=24℃, T_ext = 8℃) weather. The (absorbed) solar radiation ranges from 0 to 800 W/m2. The radiation values above 400 W/m2 are high for summer, but not for winter, because the sun inclination is lower. The second group comprises two sets of simulations with the exterior temperature and the solar radiation varying hourly: one for a typical day of summer and another for a typical day of winter. The data used for simulations is produced by the Energyplus software.
Due to the extent of the subject, the study has been developed over a particular set of comparable geometries, and with specific climatic conditions; however, special care has been taken to avoid assumptions limiting its application.The OJVF simulated geometry comprises of four cement board tiles and five joints. Each slab is 70 cm that are separated by joints of 8 mm. The exterior coating layer is separated 0.05 m from the massive wall by the ventilated air cavity. The massive wall is composed of gypsum, a brick layer and exterior insulation with a total thickness of 21 cm. To study the heat transfer problem in the case of a conventional wall, a 3D model with the same dimensions has been created to simulate the convective loop inside the sealed air cavity. The only difference with respect to the OJVF model relies in the exterior coating which is continuous (without joints between slabs).
The CFD model developed to simulate a typical OJVF has enabled a better understanding of the ventilation effect induced by the solar radiation in the air gap of the facade. Velocity profiles, together with temperature and heat flux distributions have been compared with those obtained in a conventional sealed cavity facade.
Velocity profiles show that the air flow in the OJVF is ascending in the whole width and does not form a convective loop as in the sealed cavity facade. Moreover, the profiles show much higher velocity values in the case of OJVF. These two characteristics favour the heat removal from the cavity walls, which is one of the most claimed advantages of OJVF under radiation conditions. The air temperature in the cavity remains lower than in the conventional wall, and the heat transferred to the room is therefore lower.
The model has been also used to compare the thermal performance of both facades for the specific climatic conditions of Tehran and Yazd. The results of the simulations conclude that open-joint ventilated façade _in Tehran and Yazd city which are selected with respect to their solar radiation- can help to achieve substantial energy saving. Therefore using the OJVF in the south facade of the building in the aforementioned climates, considering their simple technology, is more suitable than conventional sealed facades.
The comparison of the energy performance of the specific OJVF and conventional façade analysed in this article shows that the open joint façade results in %20.5 energy saving for Tehran and %12 for Yazd through the south facade
At this point, it is not possible to give a definite criterion, because it is still necessary to evaluate the overall year performance of the specific OJVF geometry for each climate conditions, taking into account building costs and the price of the energy used for heating and cooling. Nevertheless, the data found in this study show that the OJVF could be a more energy efficient system than the conventional sealed facade, and help to reduce the cooling needs, mainly for south orientations in places with hot summers and mild winters.
Volume 6, Issue 3 (6-2021)
Abstract
Aim: The purpose of this paper is to examine the factors associated with the occurrence of shoulder pain, neck pain, upper back pain and lower back pain with particular focus on carrying schoolbags.
Method and Materials: A questionnaire containing a range of MusculoSkeletal Pain (MSP) related information was designed specifically for a group of schoolchildren aged 11 to 20 years and distributed to Grade 7 to Grade 13 students attending three main secondary education schools in Mauritius over the period July 2017 to February 2018. A total of 1048 questionnaires were circulated out of which 849 were useable. The study analyzed the impact of socio-economic characteristics, student perception of use of tablets, type of schoolbag, private tuition, performance, duration of bag carriage and anthropometric characteristics on musculoskeletal pain. Logistic regressions models were applied to inspect how those recorded factors contribute to the occurrence of musculoskeletal pain.
Findings: The main findings in this paper indicate that students from single-sexed girl and mixed schools relative to boys’ schools, student perception of tablet use, backpack schoolbag relative to handbag and shoulder-bag, performance, total weight and excess weight of schoolbags have significant positive impact on musculoskeletal pain.
Conclusion: The results point towards the importance of raising awareness among students to achieve a positive musculoskeletal health. Information obtained is deemed to affect schoolbook and equipment-carrying behaviour and future choice of schoolbag type.
Volume 7, Issue 3 (9-2019)
Abstract
The theme of Isfahani and Hindi style poetry is ultimately selected, and since the poetry of Saadi and Hafez humorous people to think. Such a poetic style is unmatched by Iranian literary historians in the periods of Khorasani and Iraqi. It was not considered by the poets and poets of the later period, as well as by the dictators, and they wrote in the Tazkars, it was difficult to select from several tens of thousands of bits of Sa'eb. Today, Biddle's poetry is unfamiliar to Iranian professors and students, and returns to his unusual surprise in his poetry. Therefore, the present research can somehow clarify and distinguish the styles of Isfahan and Hindi and the two representatives of these two styles, Saeb and Biddle. On the same basis, the following article proves the following hypotheses by examining and analyzing the two abovementioned styles: most literary critics have considered the style of Hindi and Esfahani as one of them, and they have mentioned many common aspects, but with a little delay it can be seen that these two styles Despite abundant common features, they do not fit perfectly. Paying attention to the three elements of language, time and place in Saeb and Biddle's poetry reveal the poetic differences between these two poets and prove their style.
Volume 7, Issue 4 (4-2019)
Abstract
Aims: A pregnant woman’s nutrition is the main source for fetal development that affects both her and the fetus. The aim of this study was to investigate the effect of educational intervention on appropriate pregnancy weight gain in first-time pregnant women.
Materials & Methods: This quasi-experimental study was conducted on 86 first-time pregnant women who attended eight urban health centers in Khorram Darreh, Zanjan, Iran in 2018-2019. The subjects were selected by stratified sampling method and randomly divided into intervention (N=43) and control (N=43) groups. Before intervention, maternal body mass index was measured and the NUTRIKAP questionnaire was used on both groups. The education was provided by a trained nutritionist in three hour-long sessions in the first, second, and third trimesters of pregnancy. The posttest was done immediately after training. At the end of the third trimester, the weight of the pregnant women was measured in both groups. Data were analyzed by SPSS 16 software using independent T, Chi-Square, and Univariate ANCOVA tests.
Findings: By controlling the pre-test effect, after the intervention, the mean scores of knowledge (p=0.019) and practice (p<0.001) were significantly different between intervention and control groups, but there was no significant difference between the two groups in terms of attitude variable (p=0.311). The two groups had a statistically significant difference in weight gain during pregnancy (p<0.015).
Conclusion: The educational intervention is effective on appropriate pregnancy weight gain in first-time pregnant women.
Volume 8, Issue 2 (6-2020)
Abstract
Aims: In the present study, random forest (RF) and support vector machine (SVM) were used to assess the applicability of ensemble modeling in landslide susceptibility assessment across the Kolijan Rostaq Watershed in Mazandaran Province, Iran.
Materials & Methods: Both models were used in two modeling modes: 1) A solitary use (i.e., SVM and RF) and 2) Their ensemble with a bivariate statistical model named the weights of evidence (WofE) which then generated two more models, namely SVM-WofE and RF-WofE. Further, the resulting maps of each stage were dually coupled using the weighted arithmetic mean operation and an intermodal blending of the previous stages.
Findings: Accuracy of the models was assessed via the receiver operating characteristic (ROC) curves based on which the goodness-of-fit of the SVM and the SVM-WofE models were 0.817 and 0.841, respectively, while their respective prediction accuracy values were found to be 0.848 and 0.825. The goodness-of-fit of the RF and the RF-WofE models respectively was 0.9 and 0.823, while their respective prediction accuracy values were found to be 0.886 and 0.823. The goodness-of-fit and prediction power of SVM and SVM-WofE ensemble were respectively 0.859 and 0.873. The same increasing pattern was evident for the ensemble of RF and RF-WofE where their goodness-of-fit and prediction power increased, respectively, up to 0.928 and 0.873. Moreover, the goodness-of-fit and prediction power of RF-SVM ensemble were increased up to 0.932 and 0.899, respectively. The results of the averaged Kappa values throughout a 10-fold cross-validation test as an auxiliary accuracy assessment attested to the same results obtained from the ROC curves.
Conclusion: Successive intermodal ensembling approach is a simple and self-explanatory method so far as the context of many data mining techniques with a highly complex structure has been simply benefitted from the weighted averaging technique.
Volume 9, Issue 1 (12-2009)
Abstract
A honeycomb panel consists of an array of open hexagonal cells which their walls are perpendicular to face sheets although other panel sandwiches don’t have these perpendicular walls. Their design is often performed based on minimum weight. This research is aimed at minimizations of weight by means of computing honeycomb core girth. Weight optimization is done by means of Naive and numerical procedures. Numerical optimization is done by the sequential quadratic programming (SQP) method. Geometric parameters and optimized weight are calculated for hexagonal and square cells. Optimized weights for these two cross-sections are compared.
Keywords: Honeycomb Weight Optimization, Sandwich Panels, Numerical optimization, Sequential Quadratic Programming.
Volume 9, Issue 1 (4-2009)
Abstract
The purpose of this paper is to investigate the effect of increasing electricity price on compensated variation (CV) and deadweight loss (DWL) of different income groups in Iran over the 1967-2004 period. An autoregressive distributed lag (ARDL) model is employed and five electricity demand functions are estimated for different income groups and based the estimates, CV and DWL are calculated. The effects of electricity price increase on CV and DWL are examined and the following results are obtained:
• Comparing CV in different income groups shows that CV increases from the poor to the rich.
• Comparing DWL in different income groups shows that DWL increases from the poor to the rich.
• By increasing electricity price and using direct subsidy, the welfare of low and middle income groups increase while the welfare of high income groups decrease.