• Journal of Radiation Protection and Research
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• v.47 no.1
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• pp.39-49
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• 2022

Background: For proper monitoring of the eye lens dose, an appropriate calibration factor of a dosimeter and information about the mean energies of X-rays are indispensable. The scattered X-ray energy spectra should be well characterized in medical practices where eye lenses of medical staffs might be high. Materials and Methods: Scattered X-ray energy spectra were experimentally derived for three different types of X-ray diagnostic and therapeutic equipment, i.e., the computed tomography (CT) scan, the angiography and the fluoroscopy. A commercially available CdZnTe (CZT) spectrometer with a lead collimator was employed for the measurement of scattered X-rays, which was performed in the usual manner. Results and Discussion: From the obtained energy spectra, the mean energies of the scattered X-rays lied between 40 and 60 keV. This also agreed with that obtained by the conventional half value layer method. Conclusion: The scattered X-rays to which medical workers may be exposed in the region around the eyes were characterized by means of spectrometry. The obtained mean energies of the scattered X-rays were found to match the flat region of the dosimeter response.

• Advances in Energy Research
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• v.8 no.2
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• pp.111-123
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• 2022

Solar Energy is the energy of solar radiation carried by them in the form of heat and light. It can be converted into electricity. Solar potential depends on the site's atmosphere; the solar energy distribution depends on many factors, e.g., turbidity, cloud types, pollution levels, solar altitude, etc. We estimated solar radiation with the help of the Ashrae clear-sky model for three locations in Pakistan, namely Pasni, Gwadar, and Jiwani. As these locations are close to each other as compared to the distance between the sun and earth, therefore a slight change of latitude and longitude does not make any difference in the calculation of direct beam solar radiation (BSR), diffuse solar radiation (DSR), and global solar radiation (GSR). A modified formula for declination angle is also developed and presented. We also created two different models for Ashrae constants. The values of these constants are compared with the standard Ashrae Model. A good agreement is observed when we used these constants to calculate BSR, DSR, GSR, the Root mean square error (RMSE), Mean Absolute error (MABE), Mean Absolute percent error (MAPE), and chisquare (χ²) values are in acceptance range, indicating the validity of the models.

• Advances in Energy Research
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• v.4 no.1
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• pp.87-106
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• 2016

In this research, optimum design of the combined solar collector, geothermal heat pump and thermal seasonal storage system for heating and cooling a sample greenhouse is studied. In order to optimize the system from technical point of view some new control strategies and functions resulting from important TRNSYS output diagrams are presented. Temperatures of ground, rock bed storage, outlet ground heat exchanger fluid and entering fluid to the evaporator specify our strategies. Optimal heat storage is done with maximum efficiency and minimum loss. Mean seasonal heating and cooling COPs of 4.92 and 7.14 are achieved in series mode as there is no need to start the heat pump sometimes. Furthermore, optimal parallel operation of the storage and the heat pump is studied by applying the same control strategies. Although the aforementioned system has higher mean seasonal heating and cooling COPs (4.96 and 7.18 respectively) and lower initial cost, it requires higher amounts of auxiliary energy either. Soil temperature around ground heat exchanger will also increase up to $1.5^{\circ}C$ after 2 years of operation as a result of seasonal storage. At the end, the optimum combined system is chosen by trade-off between technical and economic issues.

• Wind and Structures
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• v.35 no.6
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• pp.385-394
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• 2022

The energy demand of the world is increasing rapidly, mainly using fossil energy, which causes environmental damage. The wind is free and clean energy to solve the environmental problems. Thailand is one of the developing nations, and the majority of its energy is obtained from petroleum, natural gas and coal. The objective of this study is to test the characteristics of wind energy at Khon Kaen in Thailand. The wind measurement tools, the 3-cup anemometers to measure wind speed, and wind vanes to measure wind direction, were mounted on a wind tower mast to record wind data at the heights of 60, 90 and 120 meters above ground level (AGL) for 5 years between January 2012 and December 2016. The results show that the annual mean wind speeds were 3.79, 4.32 and 4.66 m/s, respectively. The highest mean wind speeds occurred in June, August and December, in order, and the lowest occurred in September. The majority of prevailing wind directions were from the North-East and South-West directions. The average annual wind shear coefficient was 0.297. Furthermore, five wind turbines with rated power from 0.85 to 4.5 MW were selected to estimate the wind energy output and it was found that the maximum AEP and CF were achieved from the low cut-in speed and high hub-height wind turbines. This important information will help to develop wind energy applications, such as the plan to produce electricity and the calculation of the wind load that affects tall and large structures.

• Journal of the Korean housing association
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• v.22 no.6
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• pp.31-42
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• 2011

The purpose of the study was to investigate the characteristics of energy use behaviors and energy saving consciousness of multi-family housing residents. The energy referred to in this study includes electric energy, heating energy and water usage. This study was conducted from a survey carried out in Seoul and Gyeonggi-do. The results of the study are as follows: First, among the survey questions, the only positive energy saving behaviors shown by the occupants was turning off the lights and the television, and in the use of kitchen appliances; it could therefore be concluded that, in general, energy saving attitude and consciousness were not sufficient to reduce energy consumption. Second, the results showed high mean scores for the behaviors which were easy to control, such as turning off lights and televisions, and low mean scores for the behaviors which required extra effort to completely cut off electricity energy such as pulling out the plugs of electronic appliances. Third, it was found that the occupants generally showed the tendency to save heating energy. However, in cases where the occupants were required to continuously and directly experience indoor temperatures, they expressed passive attitudes toward saving energy. Fourth, they showed wasteful attitudes toward water usage by leaving the tap running when taking showers and washing their faces. Fifth, while they showed a strong energy saving consciousness, they also showed a passive attitude about putting this into practice; there was therefore some gap between attitude and behavior. Lastly, among the socio-demographic factors, age and family lifecycle were very important factors affecting energy use and energy saving consciousness.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.6
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• pp.845-852
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• 2008

The goal of this study was to determine whether galanin affects the mean plasma concentrations of metabolic parameters such as thyroxine (T4), triiodothyronine (T3), growth hormone (GH), insulin, glucagon, glucose, fatty acid and urea in goats fed diets differing in energy content. Sixteen goats were randomly divided into 4 groups. Animals in groups 1 and 2 were fed 100% and animals in groups 3 and 4 were fed 50% energy content in the diet for 20 days. After 20 days, animals in groups 1 and 3 received a daily infusion of $1{\mu}g$ galanin and groups 2 and 4 received a daily infusion of $2{\mu}g$ galanin into their third ventricle for 5 days. Blood samples were collected daily from the jugular vein before infusion on day 4 until 4 days after the last infusion of galanin. Samples were assayed for plasma T3, T4, GH, insulin and glucagon concentrations by double-antibody RIA. Glucose, fatty acid and urea concentrations were also measured. Lower dietary energy intake and infusions of 1 and $2{\mu}g$ galanin significantly (p<0.01) decreased the mean plasma concentrations of T3, T4, insulin and glucose and significantly (p<0.01) increased the mean plasma concentrations of GH, glucagon, fatty acid and urea of the animals in groups 3 and 4. Different dosages of the galanin infusions did not change the plasma concentrations of the metabolic parameters in the animals fed a normal dietary energy content. The results of this experiment indicated that galanin may negatively affect T3, T4, insulin and glucose and increase GH, glucagon, fatty acid and urea in goats with negative energy balance, but not in those with positive energy balance.

• Korean Journal of Community Nutrition
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• v.2 no.5
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• pp.695-700
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• 1997

This study was conducted to investigate the effect of an energy restriction program on the weight loss and changes of the biochemical nutritional status for 35 obese women. The energy restriction program took place over a 3-week period that was devided into two parts. The first part consisted of 750-800kcal diet and the second part of 800-1000kcal. Subjects were provided a low energy formula and a menu for the recommended diet. Anthropometric and biochemical measurement before and after the energy restriction program were estimated. Mean weight loss was 3.0kg, accordingly the obestiy rate was lowered from 40.2 to 34.4, BMI from 29.2 to 28.9 and fat weight from 23.3kg to 21.0kg( <0.01. <0.05). Waist circumference loss was most prominent(4.4%) compared to triceps(21% loss)and hip circumference(2.2%loss). Mean RBC count, hemoglobin and hematocrit were significantly lowered( <0.01) but they were in the normal range. Systolic blood pressure was significantly decreased from 124.1mmHg to 113.1mmHg . Mean SGOT and SGPT were lowered from 29.3u/L to 20.0u/L and from 28.7u/L to 16.6u/L, respectively. It seems that the 3 weeks of energy restriction program used in this study was effective in improving anthropometric measurements without producing deficiency of iron or other susceptible nutrients.(Korean J community Nutrition 2(5) : 695-700,1997)

• Journal of Nutrition and Health
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• v.30 no.7
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• pp.854-869
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• 1997

This study was conducted to evaluation the quality of meals served in elementary school based on nutrient contents and food diversity . A questionnaire was mailed to school foodservice dietitians requesting one week menus for April and October . Menus served in 388 schools from each province and from major cities in Korea were analyzed. Mean nutrient contents per meal of persons served, and food expenses per meal. Mean percentages of energy from fat was 20.2% , and was significantly l different by foodservice system. When nutrient contents were converted to amount per 1, 000kcal, all were higher than that calculated from RDA except calcium, iron, and Vitamin A. Most of these were not significantly different according to area, foodservice system, the number of persons served, and food expense per meal. Compared to 1/3 of RDA for children , many meals provided lower amounts of energy, Vit A, VitB2, and Ca. More than half of the meals provided less iron than 1/3 RDA for 10-12 years girls. Using the highest values of RDA for the elementary school age group as evaluation, criteria nutrient adequacy ratios(NAR) were lowest for Ca(0.61), Vit A(0.57), and iron(0.77). The mean adequacy ratio(MAR) was 0.86. Mean numbers of food items and dishes per meal were 15.3 and 5.1 , respectively. 66.3% of the meals provided three food groups of grain, meat, and vegetable. Except for the number of different food items served per meal, the aspect of food diversity was similar to that of nutrient contents. There was significant positive correlation between mean number of different food items served per meal and nutrient content . In summary , schools in small cities and rural areas than those in large cities, schools adapting commissary or joint management than those or density. Also the more food groups served per meal, the higher the nutrient content per meal . In summary , schools in small cities and rural areas than those in large cities, schools adapting commissary or joint management than those adapting conventional foodservice system, schools serving smaller number of persons, and schools with higher food expenses provided higher energy contents and food diversity.

• Journal of the Korean Society of Food Science and Nutrition
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• v.22 no.5
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• pp.531-538
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• 1993

A 4-week energy balance study was conducted to estimate the energy expenditure (EE) of 16 primary school age boys and girls, 8 to 12 year age, by measurement of energy intakes and changes in body energy (BE) content (intake / balance technique), keeping their normal living pattern and eating behavior. Gross energy intake (GE) and fecal energy (FE) loss was measured by bomb calorimetry. Urinary energy (UE) loss was calculated from nitrogen excreted. Fat mass (FM) was determined from body density estimated from skinfold thickness. Mean constitutional ratio of carbohydrate, protein and fat for the total energy intake was 10.1 $\pm$1.8%, 12.2$\pm$0.1% and 17.1$\pm$2.0% for the boys and 74.0$\pm$1.7%, 10.7$\pm$0.3% and 15.3$\pm$0.5% for the girls, respectively. Fecal energy loss was 5.1% and 4.5% proportion of the gross energy intake for the boys and girls, respectively. Mean daily metabolizable energy estimated by subtract feral and urinary energy loss was 1862$\pm$15kcal for the boys and 1627$\pm$20kcal for the girls. Total body energy change estimated from body composition change over 28 days was increased 1524$\pm$539kcal for the boys and 3622$\pm$718kcal for the girls. Mean daily energy expenditure was 1812$\pm$37kcal(52 $\pm$2kcal/kg of body weight) for the boys and 1487$\pm$25kca1 (52$\pm$2kcal/kg of body weight) for the girls.

• Journal of the Korean Society of Food Science and Nutrition
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• v.21 no.1
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• pp.1-8
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• 1992

A 4-week energy balance study was conducted to estimate the energy expenditure (EE) of 7 high school age men, 16 to 18 year of age, by measurement of energy intakes and changes in body energy (BE) content (intake/balance technique), keeping their normal living pattern and maintenance body weight. Gross energy intake (GE) and fecal energy (FE) loss was measured by bomb calorimetry, Urinary energy (UE) loss was calculated from nitrogen excreted. Fat mass (FM) was determined from body density estimated from skinfold thickness. 1) Mean constitutional ratio of carbohydrate, protein and Int for the total energy intake was $73.7{\pm}0.3%$, $13.5{\pm}0.3%$ and $12.9{\pm}0.5%$, respectively. 2) Fecal energy loss was 2.4% proportion of the gross energy intake. 3) Mean daily metabolizable energy estimated by subtract fecal and urinary energy loss was $2582{\pm}61\;kcal$. 4) Total body energy change estimated from body composition change over 28 days was decreased $4309{\pm}1837kcal$. 5) Mean daily energy expenditure was $2736{\pm}59kcal\;(46{\pm}1kcal/kg$ of body weight).