• Journal of Korean Society of Environmental Engineers
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• v.34 no.4
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• pp.223-231
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• 2012

The purpose of this study is to investigate basically the mechanism of heat transfer by the resolution of complex fluid flow inside a sophisticated designed screw dryer for the treatment of sewage sludge by using numerical analysis and experimental study. By doing this, the result was quite helpful to obtain the design criteria for enhancing drying efficiency, thereby achieving the optimal design of a multiple screw type dryer for treating inorganic and organic sludge wastes. One notable design feature of the dryer was to bypass a certain of fraction of the hot combustion gases into the bottom of the screw cylinder, by the fluid flow induction, across the delicately designed holes on the screw surface to agitate internally the sticky sludges. This offers many benefits not only in the enhancement of thermal efficiency even for the high viscosity material but also greater flexibility in the application of system design and operation. However, one careful precaution was made in operation in that when distributing the hot flue gas over the lump of sludge for internal agitation not to make any pore blocking and to avoid too much pressure drop caused by inertial resistance across the lump of sludge. The optimal retention time for rotating the screw at 1 rpm in order to treat 200 kg/hr of sewage sludge was determined empirically about 100 minutes. The corresponding optimal heat source was found to be 150,000 kcal/hr. A series of numerical calculation is performed to resolve flow characteristics in order to assist in the system design as function of important system and operational variables. The numerical calculation is successfully evaluated against experimental temperature profile and flow field characteristics. In general, the calculation results are physically reasonable and consistent in parametric study. In further studies, more quantitative data analyses such as pressure drop across the type and loading of drying sludge will be made for the system evaluation in experiment and calculation.

• Journal of the Korean Applied Science and Technology
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• v.37 no.4
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• pp.649-658
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• 2020

The purpose of this study is to verify the difference in health and obesity according to water and coffee intake. The study subject is 900 female college students. Physical fitness factors measured in this study were physical strength(grip strength, back muscle strength), muscle endurance (sit-up), Flexibility(Sit & reach) and cardiopulmonary endurance(harvard step). The factors of body composition (intracellular fluid, extracellular fluid, protein, mineral, body water content, muscle mass, lean body mass, body fat mass) and obesity (BMI, body fat percentage, abdominal fat percentage, obesity) were measured with the Inbody equipment. SPSS program was used for all data analysis. Group differences were verified by two-way ANOVA and one-way ANOVA. The results are as follows. There was no interaction effect between water and coffee intake on health and obesity. Therefore, the difference of the dependent variables according to each independent variable was verified. There was no significant difference in physical fitness according to water intake and coffee intake, but there was a significant difference in body composition (intracellular fluid, protein, minerals, body water, muscle mass and lean body mass). Water drinking group more than 7 cups had significantly higher body composition than the 1-4 cups water drinking group. In the case of coffee, the body composition of the 3 cup intake group was significantly higher than that of the none intake group. Obesity was significantly higher than the none intake and 1-2 cup intake groups. Based on the study results, water intake was not related to obesity, but coffee was related. For further studies, it would be better to consider gender and age differences in drinking various beverages such as water and coffee and that would be used to suggest a desirable way of water intake according to individual characteristics of the better health.

• Korean Journal of Cognitive Science
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• v.15 no.2
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• pp.1-15
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• 2004

The structure of sensibility from motion was developed for the purpose of understanding relationship between sensibilities and physical factors to apply it to dynamic visual display. Seventy adjectives were collected by assessing adequacy to express sensibilities from motion and reporting sensibilities recalled from dynamic displays with achromatic color. Various motion displays with a moving single dot were rated according to the degree of sensibility corresponding to each adjective, on the basis of the Semantic Differential (SD) method. The results of assessment were analyzed by means of the factor analysis to reduce 70 words into 19 fundamental sensibilities from motion. The Multidimensional Scaling (MDS) technique constructed the sensibility space in motion, in which 19 sensibilities were scattered with two dimensions, active-passive and bright-dark Motion types systemically varied in kinematic factors were placed on the two-dimensional space of motion sensibility, in order to analyze important variables affecting sensibility from motion. Patterns of placement indicate that speed and both of cycle and amplitude in trajectories tend to partially determine sensibility. Although color and motion affected sensibility according to the in dimensions, it seemed that combination of motion and color made each have dominant effect individually in a certain sensibility dimension, motion to active-passive and color to bright-dark.

• Journal of Korean Physical Therapy Science
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• v.9 no.3
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• pp.31-49
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• 2002

The purpose of this study was to investigate discomforts and sexual life and to identify the relation between the discomforts and sexual life with low back pain. The data were collected from March 2 through July 31, 2001. Four hundred forty-two questionnaires were returned (response rate=88.0%). Analysis of the data was done with SPSS PC+ and use descriptive statistics, $x^2$-test, t-test, ANOVA. regression. The statistics shows that over than 80% of the adults experienced lumbago at least one time in their life, and Back pain is known as one of the most common complaints made by the patients of all ages in the general hospital or local medical clinics throughout. However, in certain case it leads to a chronic condition which can cause a great deal of problems in management and in financial burden to individuals and society. The result of this study was summarized as follows: 1) It appeared that regarding the distribution of gender, male was the higher(63.6%) then that of female, the portion of forties was 28.5%. Sitting for long time was 23.1% in men and 21.7% in women. Unknown reason including sexual behaviour was 12.9% in men and 15.5% in women. Patients treated medicine and physical therapy were 36.4%. In level of educational background, the rate of high school was 31.0%, technical college was 28.5%. The highest proportion by occupation was 18.3% of office workers, occupation posture was 41.9% of sitting. 2) Men(26.0%) and most of women(34.8%) were not satisfied in the explanation satisfaction rate of sex life concerned disease. 23.8% in men and 23.6% in women considered flexibility of waist good. Man(33.3%) and most of woman(35.0%) considered that Health education is necessary. 32.7% in men and 27.3% in women did't mind educator is whoever. Preventing of lower back pain(LBP) and proper Health education of sex life are demanded in daily life. 3) 58.0% of man and 64.0% of woman mostly had a posture which is man over woman. 28.5% in men and 27.8% in women considered that proper information finding of LBP and sex life was very few and few. 37.7% in men and 42.7% in women have acquired information about sex life flung their friends. 4) The number of sex life was decreased from 2.96 0.98 to 2.61 1.63 and also the time of sex life was decreased from 3.65 1.89 to 226 1.64. The satisfaction rate of sex life changed from 3.60 0.86 to 2.77 1.10. In the number of sex life, The non correct group was 2.62 1.91 and the correct group was higher in 2.68 1.65. In the time of sex life, The non correct group was 2.02 1.47 and the correct group was higher in 229 1.65. The satisfaction rate of sex life was 2.76 0.86 in non correct group and 2.88 1.10 in correct group. So there was a difference. 5) In the satisfaction rate of sex life, Men who have a lower back pain were higher than women and no attack group was higher than attack group. As they had many sex life, the satisfaction rate was higher significantly in statistics. As the time of sex life was short, the satisfaction rate was lower significantly in statistics. As the age was low, the demand rate of Health education was high and as means of patient who had a lower back pain was high, the demand rate of Health education was high. As the patient who had a lower back pain had a long married life, the demand rate of Health education was high and as education level was high, the demand rate of Health education was high. It is necessary to provide patients with conservative treatment, educational teaching, and training to prevent further injuries in the future. In general, it is important to educate the public how to prevent back injuries and how to treat themselves in an onset period to prevent further injuries sliding into a chronic state. Sexuality is an integral part of normal and healthy relationships, but patients are unable to enjoy sex because they are riot able to get into a comfortable position due to back pain. Many conditions of the spine can make certain positions uncomfortable. Health educator should make the education program of the discomforts and the sexual pattern for low back pain in workplace and/or hospital. Further study Is needed on how to integrate the educational program on sexuality into the total rehabilitation program.

• Journal of the Korean Applied Science and Technology
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• v.36 no.4
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• pp.1060-1068
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• 2019

The physical fitness of the cadets of the Air Force Academy, which will protect the airspace of the Republic of Korea, is of paramount importance to fulfill the given mission. Therefore, the purpose of this study was to confirm the characteristics of body composition and physical fitness of female cadets of Air Force Academy and to verify their relationship with physical fitness according to body fat % level of total female cadets. To achieve the purpose of the study, 50 female cadets of the Korea Air Force Academy (1grade 13, 2grade 18, 3grade 9, 4grade 10) were measured in body composition (skeletal strength, body fat mass, body mass index, body fat %, abdominal obesity rate, basal metabolic rate) and physical fitness (muscle strength, muscular endurance, power, agility, flexibility and balance). One way ANOVA was performed for data processing to identify body composition and physical fitness characteristics by grade and to identify differences in physical fitness according to body fat rate levels. According to the study, the 1 grade was lower in body fat mass and body fat % among female cadets, the 2 grade was lower than the 3 and 4 grades, and the body mass index was lower than the third and fourth grades. Also, there was no difference in the physical fitness of the rest of the year. The intergroup physical fitness according to the body fat rate was higher than that of those with less than 20 percent of net worth and 25 percent to less than 25.1 percent to 30 percent, while those with less than 20 percent balance were higher than those with less than 25.1 to 30 percent. The results of this study showed differences in body composition by grade in female cadets, especially in power and balance according to body fat %. Therefore, female cadets of the Air Force Academy need to manage body fat to have the power and balance capability related to the airborne mission environment.

• Journal of Korean Home Economics Education Association
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• v.15 no.4
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• pp.115-132
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• 2003

The purpose of this study is aimed at giving proof that helps the elementary practical arts education system accomplish as the effects are turned out experimentally. Two classes of the sixth grade of J elementary school in Dae-gu have been selected in order to be experimented. One was chosen as an experimental group, the other was done as a comparative group. The creative-problem-solving learning-model was applied to the experimental group, and the traditional way of teaching was applied to the comparative group. For four classes of the sixth grades, ‘chapter 8: Making with recycled materials’ was proceeded as the content. Then. tests about the way of environmental awareness and creativity were carried out twice. After that, the results of pre and after-test in the comparative and experiment groups were compared using the t-test method. Following the analysis of the data collected in this study. the following major observations were obtained: First, children who were educated the creative problem-solving in a practical arts education achieved higher scores than before. Therefore, it turns out that the CPS method is an effective way to improve the environmental awareness in children. It showed that it included lots of daily habits connected with daily life and it made the intention to carry out the environment-preservation stronger and children´s attitude towards the environment improved. Moreover, making with recycled materials was used to solve an environmental problem, affecting in a positive way in our life. It also made the positive recognition about the environment. Second. the application of the creative problem-solving class of the practical arts education can make positive results to children. It helped children to have more interest in the environment around them. Children´s fluency, flexibility and originality in their ideas were improved as much as possible while they were solving problems. Consequently, the application of the creative problem-solving class model of elementary practical arts environmental education lets children expand environment consciousness and creativity.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.27 no.12C
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• pp.1288-1298
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• 2002

To implement elliptic curve cryptosystem in GF(2$\^$m/) at high speed, a fast divider is required. Although bit-parallel architecture is well suited for high speed division operations, elliptic curve cryptosystem requires large m(at least 163) to support a sufficient security. In other words, since the bit-parallel architecture has an area complexity of 0(m$\^$m/), it is not suited for this application. In this paper, we propose a new serial-in serial-out systolic array for computing division operations in GF(2$\^$m/) using the standard basis representation. Based on a modified version of tile binary extended greatest common divisor algorithm, we obtain a new data dependence graph and design an efficient bit-serial systolic divider. The proposed divider has 0(m) time complexity and 0(m) area complexity. If input data come in continuously, the proposed divider can produce division results at a rate of one per m clock cycles, after an initial delay of 5m-2 cycles. Analysis shows that the proposed divider provides a significant reduction in both chip area and computational delay time compared to previously proposed systolic dividers with the same I/O format. Since the proposed divider can perform division operations at high speed with the reduced chip area, it is well suited for division circuit of elliptic curve cryptosystem. Furthermore, since the proposed architecture does not restrict the choice of irreducible polynomial, and has a unidirectional data flow and regularity, it provides a high flexibility and scalability with respect to the field size m.

• KDI Journal of Economic Policy
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• v.34 no.2
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• pp.55-93
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• 2012

In Korea, energy policies are actualized through various energy-related plans. Recently, however, as high-ranking plans, which are very vision-oriented, continually set higher sector-by-sector goals, subordinate action plans, which require consistency, encounter distortions in their establishment process. Also, each subordinate action plan reveals limitations in terms of securing flexibility of the plan in responding to uncertainties of the future. These problems pose potential risks such as causing huge social costs. In this regard, with an aim to provide empirical evidence for discussions on improving the procedure for developing and executing Korea's energy plans, this study mainly analyzes the Basic Plan on Electricity Demand and Supply-one of the most important subordinate action plans-in order to explain the problems of the Basic Plan in a logical manner, and potential problems that could occur in the process of sustaining consistency between the Basic Plan and its higher-ranking plans. Further, this paper estimates the scale of social costs caused by those problems assuming realistic conditions. According to the result, in the case of where maximum electric power is estimated to be 7% (15%) less than the actual amount in the Basic Plan on Electricity Demand and Supply, the annual generation cost will rise by 286 billion won and (1.2 trillion won) in 2020. Such social costs are found to occur even when establishing and executing the Basic plan according to the target goal set by its higher-ranking plan, the National Energy Master Plan. In addition, when another higher-ranking GHG reduction master plan requires the electricity sector to reduce emissions by additional 5% in the GHG emissions from the right mix in electricity generation with 'zero' cost of carbon emission, the annual generation cost will rise by approximately 915 billion won in 2020. On the other hand, the analysis finds that since economic feasibility of electric powers in Korea varies significantly depending on their type, Korea is expected to face very small potential social costs caused by uncertainties over the future price of carbon dioxide in the process of establishing the Basic Plan.

• Journal of Bio-Environment Control
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• v.29 no.2
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• pp.161-170
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• 2020

There is systematic spatial variations in environmental properties due to sensitive reaction to external conditions at plastic greenhouse occupied 99.2% of domestic agricultural facilities. In order to construct 3 dimensional distribution of temperature, relative humidity, CO₂ and illuminance, measurement matrix as 3 by 3 by 5 in direction of width, height and length, respectively, dividing indoor space of greenhouse was designed and tested at experimental site. Linear regression analysis was conducted to evaluate optimal estimation method in terms with horizontal and vertical variations. Even though sole measurement point for temperature and relative humidity could be feasible to assess indoor condition, multiple measurement matrix is inevitably required to improve spatial precision at certain time domain such as period of sunrise and sunset. In case with CO₂, multiple measurement matrix could not successfully improve the spatial predictability during a whole experimental period. In case with illuminance, prediction performance was getting smaller after a time period of sunrise due to systematic interference such as indoor structure. Thus, multiple sensing methodology was proposed in direction of length at higher height than growing bed, which could compensate estimation error in spatial domain. Appropriate measurement matrix could be constructed considering the transition of stability in indoor environmental properties due to external variations. As a result, optimal measurement matrix should be carefully designed considering flexibility of construction relevant with the type of property, indoor structure, the purpose of crop and the period of growth. For an instance, partial cooling and heating system to save a consumption of energy supplement could be successfully accomplished by the deployment of multiple measurement matrix.

• Archives of design research
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• v.12 no.4
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• pp.231-241
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• 1999

This study propose to analyze the design method and the form elements of museums, of works by Richard Meier, and through the analysis, spacial characteristics of museums will be understood. The museum works of Richard Meier, as an exhibition space, not only display the art works efficiently, but they also offer visitors the opportunity to experience the art of architecture, as a cultural space. Richard Meier, when working on the projects, has utilized the design methods and the architectural language, learned from Mies van der Rohe and Le Corbusier, resourcefully. Having the structural grid as basis, the rational rectangular forms were intended for exhibition space, while the circular and partial circular forms of geometry were utilized in formative space. This was able to maintain the balance between functional and formative space. In the museums of his works, the ramp and the glass wall separated from the structure become very important means of expression. The ramps, not only make people to enjoy the interior and exterior of museum, but also able them to see the works of art from different distances and angles repeatedly and the large glass wall reveals the various shapes of interior to exterior. In comparing with the design method and language of two masters mentioned, the design principles and elements, developed by Meier were applied to the site plans, exhibition space planning and elevations to manifest its originality. The design concept, derived from the urban fabric and historical buildings around, gave harmony to the museum with its surroundings, and employing the deformed axis brought variation and the effect of diversion to the site plan. The exhibition space is much vitalized by the well arrangement of various exhibition fixtures in the museum. The exhibion fixtures, which the partitions, shelves, miches, and stages were put together in flexibility, play multiple roles as partitions dividing spaces, as furniture displaying art works, and as elements creating forms. The systematically arranged fixtures, also produce several visual axes and centers, which have visitors appreciate the works of art in various perspectives, hence create a unique environment.