• Title/Summary/Keyword: Standard normal Distribution

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A Sensitivity Analysis of Design Parameters of an Underground Radioactive Waste Repository Using a Backpropagation Neural Network (Backpropagation 인공신경망을 이용한 지하 방사성폐기물 처분장 설계 인자의 민감도 분석)

  • Kwon, S.;Cho, W.J.
    • Tunnel and Underground Space
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    • v.19 no.3
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    • pp.203-212
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    • 2009
  • The prediction of near field behavior around an underground high-level radioactive waste repository is important for the repository design as well as the safety assessment. In this study, a sensitivity analysis for seven parameters consisted of design parameters and material properties was carried out using a three-dimensional finite difference code. From the sensitivity analysis, it was found that the effects of borehole spacing, tunnel spacing, cooling time and rock thermal conductivity were more significant than the other parameters. For getting a statistical distribution of buffer and rock temperatures around the repository, an artificial neural network, backpropagation, was applied. The reliability of the trained neural network was tested with the cases with randomly chosen input parameters. When the parameter variation is within ${\pm}10%$, the prediction from the network was found to be reliable with about a 1% error. It was possible to calculate the temperature distribution for many cases quickly with the trained neural network. The buffer and rock temperatures showed a normal distribution with means of $98^{\circ}C$ and $83.9^{\circ}C$ standard deviations of $3.82^{\circ}C$ and $3.67^{\circ}C$, respectively. Using the neural network, it was also possible to estimate the required change in design parameters for reducing the buffer and rock temperatures for $1^{\circ}C$.

The Effect of Barrel Vibration Intensity to the Plating Thickness Distribution

  • Lee, Jun-Ho;Roselle D. Llido
    • Proceedings of the Korean Institute of Surface Engineering Conference
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    • 1999.10a
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    • pp.15-15
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    • 1999
  • In chip plating, several parameters must be taken into consideration. Current density, solution concentration, pH, solution temperature, components volume, chip and media ratio, barrel geometrical shape were most likely found to have an effect to the process yields. The 3 types of barrels utilized in chip plating industry are the conventional rotating barrel. vibrational barrel (vibarrel), and the centrifugal type. Conventional rotating barrel is a close type and is commonly used. The components inside the barrel are circulated by the barrel's rotation at a horizontal axis. Process yield has known to have higher thickness deviation. The vibrational barrel is an open type which offers a wide exposure to electrolyte resulting to a stable thickness deviation. It rotates in a vertical axis coupled with multi-vibration action to facilitate mixed up and easy transportation of components, The centrifugal barrel has its plated work centrifugally compacted against the cathode ring for superior electrical contact with simultaneous rotary motion. This experiment has determined the effect of barrel vibration intensity to the plating thickness distribution. The procedures carried out in the experiment involved the overall plating process., cleaning, rinse, Nickel plating, Tin-Lead plating. Plating time was adjusted to meet the required specification. All other parameters were maintained constant. Two trials were performed to confirm the consistency of the result. The thickness data of the experiment conducted showed that the average mean value obtained from higher vibrational intensity is nearer to the standard mean. The distribution curve shown has a narrower specification limits and it has a reduced variation around the target value, Generally, intensity control in vi-barrel facilitates mixed up and easy transportation of components, However, it is desirable to maintain an optimum vibration intensity to prevent solution intrusion into the chips' internal electrode. A cathodic reaction can occur in the interface of the external and internal electrode. $2HD{\;}+{\;}e{\;}{\rightarrow}20H{\;}+{\;}H_2$ Hydrogen can penetrate into the body and create pressure which can cause cracks. At high intensity, the chip's motion becomes stronger, its contact between each other is delayed and so plating action is being controlled. However, the strong impact created by its collision can damage the external electrode's structure thereby resulting to bad plating condition. 1 lot of chip was divided into two equal partion. Each portion was loaded to the same barrel one after the other. Nickel plating and tin-lead plating was performed in the same station. Portion A maintained the normal barrel vibration intensity and portion B vibration intensity was increased two steps higher. All other parameters, current, solution condition were maintained constant. Generally, plating method find procedures were carried out in a best way to maintained the best plating condition. After plating, samples were taken out from each portion. molded and polished. Plating thickness was investigated for both. To check consistency of results. 2nd trial was done now using different lot of another characteristics.

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A Study on the Establishment of a GIS Thematic Mapping Procedure for Oil Spill Monitoring Data (유류오염 모니터링 자료의 GIS 주제도 제작 절차 수립 연구)

  • Kim, Tae-Hoon;Choi, Hyun-Woo
    • Journal of the Korean Association of Geographic Information Studies
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    • v.15 no.1
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    • pp.1-15
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    • 2012
  • Marine scientific monitoring, including monitoring of oil pollution, marine ecosystems, and the marine environment in general, has been being carried out continuously in order to assess the impact of oil pollution since the Hebei Spirit oil spill in December 2007. GIS thematic maps containing visual and summarized information are very useful for conducting exploratory analyses on the spatio-temporal variability of the marine environment and marine ecosystems due to oil pollution. Defining map types and building a legend in accordance with data characteristics are essential elements for mapping. In the present study, map types were defined according to the data attributes and GIS data types for each data item and classification of data intervals for the legend was defined by using two data distribution types through a histogram analysis. The data interval method was defined as follows: If the histogram of data has a uniform distribution, an equal interval method is applied; in the case of a normal distribution, a standard deviation method is applied. In addition, thematic map templates were made for each map type through the definition of marginal elements. Through the establishment of systematic mapping methods and procedures in this study, it was possible to effectively make standardized thematic maps for various kinds of marine scientific data.

A Study on the Effects of Selection Attributes for Agricultural Products on Using Local Food Store (농산물 구매선택 속성이 로컬푸드 직매장 이용에 미치는 영향 연구)

  • Chung, Joon-Ho;Hwang, Sung-Hyuk
    • Journal of Distribution Science
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    • v.14 no.4
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    • pp.117-125
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    • 2016
  • Purpose - As consumers' needs for purchasing fresh and safe food have been bigger in Korea, their interest in local food is also growing recently. So, the number of local food stores has been increased from 3 in 2012 to 103 in 2015. Local food stores should operate a business responding consumers' needs in order that local food stores are not to be a one-time fad. Therefore, the purpose of this study is to analyze the characteristics of consumers who use a local food store and provide helpful implications to design a strategy for sustainable growth of local food store. Research design, data, and methodology - In this study, Probit model was used for empirical analysis in order to examine the effect of purchase choice attributes of agricultural products, consumer's satisfaction, and their demographic factors upon the intention to use a local food store. After estimating coefficients of the probit model, marginal effects were calculated as a standard normal, and cumulative distribution is differentiated with respect to explanatory variables. To collect the data, questionnaire survey was carried out with the consumers using the local food store (Youngjin Nonghyup near to Jeonju city located in Jeollabuk-do). Result - The data analysis found that the more consumers are satisfied with local food store, the higher intention they have to use the local food store. In addition, it was known that the factors related to quality of agricultural products and shopping convenience among the purchase choice attributes have a considerable impact on the purchase intention of a local food store. In demographic factors, income was turned out to be an important factor affecting purchase intention of local food. Such a result supports the hypothesis that high income consumers are likely to purchase local food, which is based on the inference that consumers who have a high income tend to pursue wellbeing life. Futhermore, information delivery, through a reputable media source among general factors, was known to play an important role in forming an intention to purchase local food. According to the analysis of marginal effects, probability of purchase intention of a local food store is increased by 11.4%, if a monthly average income of a household is above 4.5 million Won(Korean currency). If purchasing satisfaction with local food stores is high, the probability of purchase intention would be increased by 24.1%. Likewise, such a probability goes up by 8.7%, 5.8%, respectively as an increasing one unit of quality of agricultural products and shopping convenience of local food stores, respectively. Conclusion - For attaining sustainable growth in a local food store, it is considered necessarily to establish a proper store operation system to meet consumers' needs, especially for quality and shopping convenience of local food. Moreover, as it was found that appropriate communication through media source has a positive effect on the intention to use local food store, PR activity seems to be necessary to expand the consumers' demands for local foods.

A Study on the Degree of Physical, Psychological and Social Adaptation of CVA Patients (뇌졸중(腦卒中) 환자(患者)의 신체적(身體的).심리적(心理的).사회적(社會的) 적응도(適應度)에 관(關)한 연구(硏究))

  • Hwang Hyun-Sook;Park Kyung-Sook
    • Journal of Korean Academy of Fundamentals of Nursing
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    • v.3 no.2
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    • pp.213-233
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    • 1996
  • This study was made on 274 apoplectics patients who received the rehabilitation therapy and tests on physical, psychological and social adaptations as outpatients in 23 general hospitals in the Seoul and Kyungi area. The basic data on degree of improvement of apoplectic patients studied from rehabilitation therapy. Data was collected over a period of 63 days, from February 21st till April, 23, 1996. The assigned physical therapist conducted direct interviews with patients after he answered the distributed questionnaires for each individual patient. The colleted data was processed by the $SPCC/C^+$ method. The results of the tests conducted to meascne the the degree of ADL dependency, depression and social activity corresponding to the physical, psychological, and social adaptation. The details are ; 1) The test to meascne the degree of ADL dependency, corresponding to the study of physical adaptation of CVA patients, indicated a mean score of 2.57(ideal score is 1.0) with a standard deviation of ${\pm}0.75$. The worst score was 3.95 while the best score was a perfect 1.0, representing a severe range of dependency. The distribution was centered with a median of 2.65 and a mode of 2.68. 2) The test to meascne the degree of depression which corresponds to the level of psychological adaptation yielded a mean of 2.99 which is higher than the normal limit of 2.45. The standard deviation was ${\pm}0.52$ and the worst score and the best score were 4.35 and Respectirdy. The distribution was centered with a median of 3.00 and a mode of 3.00. 3) The test to meascne the degree of social activities for the level of social adaptation indicated a very low mean score of 26.52 (perfect score is 144), with the standard deviation of ${\pm}16.23$. Some patients scored as high as 100, but others scored as low as 3. The distribution of social activities at a very low level was shifted to the left with a median of 24.00 and a mode of 20.00. 4) Factors influencing the level of physical, psychological and social adaptation are as follows : Factors significantly influencing the level of physical adaptation measured by ADL dependency are age, personal guardian, payer of medical expenses, and paralysis of the right arm, right leg and facial paralysis. Factors significantly influencing the level of psychological adaptation measured by the degree of depression, are age, marital status, education, medical history of individual and family, speech impediment, and facial paralysis. Factors significantly influencing the level of social adaptation measured by the degree of social activity are age, marital status, education, employment status, and the burden of medical expense. 5) The Corelationship is significant(9.00), between ADL dependeing as degree of physical adaptation and depreseion as degree of psychologial adaptation. ADL dependency is proportional to depression. But social activity is inversely protional to ADL dependeny and depression. In conclusion, the increased care for physical function of the patients is not the only necessary means to better facilitate the appropriate adaptation of CVA patients. The introduction of a solid rehabilitation program for psychological and social adaptation will also play the integral part of the treatment of CVA patients.

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Distributional Characteristics of Microcrack in Tertiary Crystalline Tuff from Northeastern Gyeongsang Basin (경상분지 북동부의 제3기 결정질 응회암에서 발달하는 미세균열의 분포특성)

  • Park, Deok-Won;Lee, Chang-Bum
    • The Journal of the Petrological Society of Korea
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    • v.18 no.4
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    • pp.315-336
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    • 2009
  • We have studied the orientational characteristics of microcrack frequency, it's length and density in Tertiary crystalline tuff from the northeastern part of the Gyeongsang Basin. 134 sets of microcracks on horizontal surfaces of 3 rock samples from Heunghae-eup were distinguished by enlarged photomicrographs of the thin sections. The variability in patterns among microcrack length-frequency histograms for three rock samples from different altitudes were derived. The pattern of histograms changes progressively from negative exponential form to log-normal form in proportion to altitude. The distribution pattern for rock sample no.1 from lower altitude shows the broad length distribution characterized by higher mean and median, and higher standard deviation. Meanwhile, this distribution pattern corresponds with characteristics of joint length distribution in sedimentary rocks of the lower part of the Gyeongsang Supergroup. The occurrence frequency of shorter microcracks increases toward both NW and NE directions from the $N0{\sim}10^{\circ}W$, with the dominant direction of $N80{\sim}90^{\circ}W$ and $N80{\sim}90^{\circ}E$, respectively. This distribution pattern represents the relative differences in formation timing among microcrack sets and the result of the new initiation of shorter microcracks. Meanwhile, the longest microcracks within $N60{\sim}70^{\circ}W$($L_{max}$:1.18 mm) and $N0{\sim}10^{\circ}W$($L_{max}$:0.80 mm) directions are seen, but this kind of microcracks are very limited in number. Whole domain of the directional angle($\theta$)-frequency(N), length(L) and density($\rho$) chart can be divided into five sections in terms of phases of the distribution of related curves. From the distribution chart, density curve shows five distinct peaks in the WNW-ESE($N70{\sim}80^{\circ}W$), NS~NNE-SSW($N0{\sim}10^{\circ}W$, $N10{\sim}20^{\circ}E$), ENE-WSW($N50{\sim}60^{\circ}E$), and nearly EW($N80{\sim}90^{\circ}E$) directions, respectively. Especially, main directions of faults correspond with the directional angle showing high density. Consequently, these distribution patterns of density curve reflect the representative maximum principal stress orientations suggested in previous studies.

A Study on the Selection of the Recommended Safety Distance Between Marine Structures and Ships Based on AIS Data (AIS 기반 해양시설물과 선박간 권고 안전이격거리 선정에 관한 연구)

  • Son, Woo-ju;Lee, Jeong-seok;Lee, Bo-kyeong;Cho, Ik-soon
    • Journal of Navigation and Port Research
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    • v.43 no.6
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    • pp.420-428
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    • 2019
  • Although marine structures are a risk factor interfering with the passage of ships, there are no obvious guidelines on the required safety distance between ships and marine structures under regulations and laws. In this study, the width of the shipping route width was set based on the AIS data to analyze the separation distance between marine structures and ships, and the ships were classified by the length of each ship. By analyzing the distribution at marine structures, this study confirmed that the ships' traffic volume was in the form of normal distribution. To statistically analyze the separation distance between the traffic distribution results and the normal distribution of ships in this study, the traffic pattern analysis around the marine structures was performed. As a result, the traffic pattern was different by length and the recommended safety distance for each length is presented accordingly. Referring to the IMO (International Maritime Organization) the standard turning circle and reference of safety separation distance between ships and offshore wind turbines of the CESMA (Confederation of European Shipmasters' Associations) and P IANC (World Association for Waterborne Transport Infrastructures), the analysis was conducted on ships that did not follow the set distance among the AIS data by setting the distance within the recommended ship safety distance to 5-7 overall length. As a result, the 5.5 length over all of the safety recommendations were selected as appropriate, and based on the above results, the two cases recommending ship safety distance were proposed.

A Study of Sexual Attitudes in University Students - Q-methodological approach- (대학생들의 성의식에 대한 태도 유형 - Q-방법론적 접근 -)

  • Kweon, Hyun Joo;Chung, Hae Kyung;Ryu, Eun Jung;Chung, Yeon Kang
    • Journal of the Korean Society of School Health
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    • v.11 no.2
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    • pp.229-241
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    • 1998
  • Because sexual awareness is changing, I have tried to classify university students' attitudes toward sex. This study examined male and female university students and used a Q-method to measure these attitudes. Out of a total of 202, 33 statements were abstracted, and a P-sample of 1-7 parties consisting of 26 persons were studied. I Q-sorted the statements with a standard of 9 points for normal distribution and analyzed the data by means of a Principal Component Analysis with a Quan PC Program. According to the result of this research, university students' attitudes toward sex are divided into three types. Type 1 are called open-minded open: They may have a surgical abortion in case of an unexpected pregnancy and sexual intercourse occurs when a man and woman feel love for each other. They don't see sexual intercourse as a means reproduction nor virginal purity as unconditional. It is remarkable that these students regard sexual intercourse as a natural thing and sex as a basic desire of human beings. In short, they show an open-minded attitude toward sex. Type 2 are supporters of virginal purity; They regard virginal purity with great importance. They insist that both man and woman should be chaste but that sexual intercourse before marriage is unfavorable only to the woman. They do not believe in sexual intercourse without love and emphasize purity in sex education. Differen from type 1, they are very negative about surgical abortion. Type 3 experss love through sex. They belive that sexual intercourse makes a couple happy and a way to express their affection for each other. In other words, the relationship between man and woman is improved through sexual intercourse. They do not think of sexual intercourse in terms of childbirth.

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A numerical simulation on the effect of hole geometry for film cooling flow (홀 형상이 막 냉각 유동에 미치는 효과에 대한 수치 해석적 연구)

  • Lee, Jeong-Hui;Choe, Yeong-Gi
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.21 no.7
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    • pp.849-861
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    • 1997
  • In this study, the effect of hole geometry of the cooling system on the flow and temperature field was numerically calculated. The finite volume method was employed to discretize the governing equation based on the non-orthogonal coordinate with non-staggered variable arrangement. The standard k-.epsilon. turbulence model was used and also the predicted results were compared with the experimental data to validate numerical modeling. The predicted results showed good agreement in all cases. To analyze the effect of the discharge coefficient for slots of different length to width, the inlet chamfering and radiusing holes were considered. The discharge coefficient was increased with increment of the chamfering ratio, radiusing ratio and slot length to width and also the effect of radiusing showed better result than chamfering in all cases. In order to analyze the difference between the predicted results with plenum region and without plenum region, the velocity profiles of jet exit region for a various flow conditions were calculated. The normal velocity components of jet exit showed big difference for the low slot length to width and high blowing rate cases. To analyze the flow phenomena injected from a row of inclined holes in a real turbine blade, three dimensional flow and temperature distribution of the region including plenum, hole and cross stream with flow conditions were numerically calculated. The results have shown three-dimensional flow characteristics, such as the development of counter rotating vortices, jetting effect and low momentum region within the hole in addition to counter rotating vortex structure in the cross stream.

A Study on The Sizes of Ready-made Clothes to Export to China - Corresponding Sizes of China Women's and Men's Ready-made Clothes Sizes Based on KS size specification- (중국수출(中國輸出) 기성복(旣成服)의 치수에 관한 연구(硏究)-KS규격(規格)을 중심(中心)으로 한 중국((中國) 여성복 (女性服)및 남성복(男性服)의 대응(對應)치수-)

  • Shim, Boo-Ja
    • Journal of Fashion Business
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    • v.11 no.4
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    • pp.152-172
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    • 2007
  • This research suggest the correspondent sizes of women's and men's ready-made clothes to export to China on the basis of KS size specification. The results of this study, with the cooperation of Sejung and Searte Companies exporting clothes to Ningbo City, Zhejiang Province in China, are as follows: 1. Corresponding Dimensions of China Women's Clothes According to Morrison's relative deviation method, the body measurement characteristics of Chines and Korean women in their 30s and 40s were compared. As a result, Chinese women were bigger in height, arm length, abdomen girth, and upper arm girth but smaller in shoulder length and shoulder width. The cluster analysis for body type classification was as follows: Type 1, tall and well-developed, was 34.8%. Type 2 with weaker upper body, medium height, narrow shoulders and a slim waist was 45%. Type 3 with stronger upper body, shortest height and wide shoulders was 20.2%. 2. Corresponding Dimensions of China Men's Clothes Based on the drop standard of KS K 0050, the body types of Chinese men in their 20s were classified. A body types were 55.77%, Y body types were 32.16%, B body types were 11.55% and BB body types were 1.51%. According to the criteria of ready-made dimensions of normal body type suggested in Korea Standards, and in consideration of the basic distribution reality of body dimensions, representative 5 sizes were selected. 3. The corresponding size specification of China women's and men's clothes based on those of KS size specification were presented here, showing product sizes and physical items in detail.