• Title/Summary/Keyword: Model Validity

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Social Philosophical Analysis of Critical Discourses on the Cultural Competence (문화적 역량 비판 담론에 관한 사회철학적 분석)

  • Kim, Gi-Duk
    • Korean Journal of Social Welfare
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    • v.63 no.3
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    • pp.239-260
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    • 2011
  • It is very interesting phenomenon that despite a broad consensus on the need for social worker to take cultural aspects into professional practice, thus to be a culturally competent, a number of materials criticising the concept of cultural competence have emerged in these days simultaneously. The main purpose of the study is to clarify such phenomenon, which means that this article is trying to analyze the contents of such critical discourse on cultural competence and the validity of those contents. The result of the study finds out that most of the arguments can be categorized into three aspects: epistemological, ethical, ontological, and that most of the main ideas of the critical discourses have been borrowed from a branch of critical social work theories, especially highly influenced from Foucault and Derrida. This article argues that critical discourses have some significant problems which make a conflict with traditional values and tenets in social work as a human service profession. First, epistemologically, the critical discourse fails to differentiate the matter of discovery from that of justification, which brings the cultural competence to the brink of agnosticism. Second, ethically, insisting that there should be no foundational criteria for cultural hierarchy in term of rightness or goodness, the critical discourses reveal their intrinsic limitations in solving ethical dilemmas and conflict in real world, which can be considered as a kind of evasion of responsibility in disguise of cultural relativism. Third, in practical vein, critical discourses are largely in effective in specifying the concrete model to realize their own ideas, and furthermore they unintentionally promote context-blind perspectives that eclipses the significance of structural and systematical impacts on the cultural identity.

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Flexural Strength of HSB I-Girder Considering Inelastic Flange Local Buckling (압축플랜지 비탄성 국부좌굴을 고려한 HSB 플레이트거더의 휨강도)

  • Cho, Eun Young;Shin, Dong Ku
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.33 no.1
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    • pp.81-92
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    • 2013
  • The ultimate flexural strength of HSB I-girders, considering the effect of local bucking, was investigated through a series of nonlinear finite element analysis. The girders were selected such that the inelastic local flange buckling or the plastic yielding of compression flanges governs the flexural strength. Both homogeneous sections fabricated from HSB600 or HSB800 steel and hybrid sections with HSB800 flanges and SM570-TMC web were considered. In the FE analysis, the flanges and web were modeled using thin shell elements and initial imperfections and residual stresses were imposed on the FE model. An elasto-plastic strain hardening material was used for steels. After establishing the validity of present FE analysis by comparing FE results with test results published in the literature, the effects of initial imperfection and residual stress on the inelastic flange local buckling behavior were assessed. The ultimate flexural strengths of 60 I-girders with various compression flange slenderness were obtained by FE analysis and compared with those calculated from the KHBDC, AASHTO LRFD and Eurocode 3 provisions. Based on the comparison, the applicability of design equations in these specifications for the flexural strength of I-girder considering flange local buckling was evaluated.

Construction of a reference stature growth curve using spline function and prediction of final stature in Korean (스플라인 함수를 이용한 한국인 키 기준 성장 곡선 구성과 최종 키 예측 연구)

  • An, Hong-Sug;Lee, Shin-Jae
    • The korean journal of orthodontics
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    • v.37 no.1 s.120
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    • pp.16-28
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    • 2007
  • Objective: Evaluation of individual growth is important in orthodontics. The aim of this study was to develop a convenient software that can evaluate current growth status and predict further growth. Methods: Stature data of 2 to 20 year-old Koreans (4893 boys and 4987 girls) were extracted from a nationwide data. Age-sex-specific continuous functions describing percentile growth curves were constructed using natural cubic spline function (NCSF). Then, final stature prediction algorithm was developed and its validity was tested using longitudinal series of stature measurements on randomly selected 200 samples. Various accuracy measurements and analyses of errors between observed and predicted stature using NCSF growth curves were performed. Results: NCSF growth curves were shown to be excellent models in describing reference percentile stature growth curie over age. The prediction accuracy compared favorably with previous prediction models, even more accurate. The current prediction models gave more accurate results in girls than boys. Although the prediction accuracy was high, the error pattern of the validation data showed that in most cases, there were a lot of residuals with the same sign, suggestive of autocorrelation among them. Conclusion: More sophisticated growth prediction algorithm is warranted to enhance a more appropriate goodness of model fit for individual growth.

Eye Tracking Using Neural Network and Mean-shift (신경망과 Mean-shift를 이용한 눈 추적)

  • Kang, Sin-Kuk;Kim, Kyung-Tai;Shin, Yun-Hee;Kim, Na-Yeon;Kim, Eun-Yi
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.44 no.1
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    • pp.56-63
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    • 2007
  • In this paper, an eye tracking method is presented using a neural network (NN) and mean-shift algorithm that can accurately detect and track user's eyes under the cluttered background. In the proposed method, to deal with the rigid head motion, the facial region is first obtained using skin-color model and con-nected-component analysis. Thereafter the eye regions are localized using neural network (NN)-based tex-ture classifier that discriminates the facial region into eye class and non-eye class, which enables our method to accurately detect users' eyes even if they put on glasses. Once the eye region is localized, they are continuously and correctly tracking by mean-shift algorithm. To assess the validity of the proposed method, it is applied to the interface system using eye movement and is tested with a group of 25 users through playing a 'aligns games.' The results show that the system process more than 30 frames/sec on PC for the $320{\times}240$ size input image and supply a user-friendly and convenient access to a computer in real-time operation.

Development of high performance and low noise axial-flow fan for cooling machine room of refrigerator using airfoil-cascade analysis and surface ridge shape (익렬 분석 및 표면 돌기 형상을 이용한 냉장고 기계실 냉각용 고성능/저소음 축류팬 개발)

  • Choi, Jinho;Ryu, Seo-Yoon;Cheong, Cheolung;Kim, Tae-hoon;Koo, Junhyo
    • The Journal of the Acoustical Society of Korea
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    • v.39 no.6
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    • pp.515-523
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    • 2020
  • This study aims to improve the flow and noise performances of an axial-flow fan for cooling the machine room in a refrigerator by using airfoil-cascade analysis and surface ridge shape. First, the experimental evaluations using a fan performance tester and an anechoic chamber are performed to analyze the flow and noise performances of the existing fan system. Then, the corresponding flow and noise performances are numerically assessed using the Computational Fluid Dynamics (CFD) techniques and the Ffowcs-Williams and Hawkings (FW-H) equation, and the validity of numerical results are confirmed through their comparisons with the experimental results. The analysis for the flow of a cascade of airfoils constructed from the existing fan blades is performed, and the pitch angles for the maximum lift-to-drag ratio are determined. The improved flow performance of the new fan applied with the optimum pitch angles is confirmed. Then, the fan blades with surface ridges on their pressure sides are devised, and the reduction of aerodynamic noise of the ridged fan is numerically confirmed. Finally, the prototype of the final fan model is manufactured, and improvements in the flow and noise performances of the prototype are experimentally confirmed.

Dynamic Response Analysis of Pneumatic Floating Breakwater Mounted Wave-power Generation System of Oscillating Water Column (진동수주형 파력발전시스템을 탑재한 공기주입식 부유식방파제의 동적거동해석)

  • Lee, Kwang-Ho;Kim, Do-Sam;Jung, Ik-Han
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.29 no.6
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    • pp.305-314
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    • 2017
  • Ocean wave energy harvesting is still too expensive despite developing a variety of wave energy converter (WEC) devices. For the cost-effective wave energy harvesting, it can be an effective measure to use existing breakwaters or newly installed breakwaters for both wave control and energy harvesting purposes. In this study, we investigated the functionality of both breakwater and wave-power generator for the oscillating water column (OWC)-type wave energy converter (WEC) installed in a pneumatic floating breakwater, which was originally developed as a floating breakwater. In order to verify the performance of the breakwater as a WEC, the air flow velocity from air-chamber to WEC has to be evaluated properly. Therefore, air flow velocity, wave transformation and motion of floating structure was numerically implemented based on BEM from linear velocity potential theory without considering the compressibility of air within the chamber. Air pressure, meanwhile, was assumed to be fluctuated by the motions of structure and the water level change within air-chamber. The validity of the obtained values can be determined by comparing the previous results from the numerical analysis for different shapes. Based on numerical model results, wave transformation characteristics around OWC system mounted on the fixed and floating breakwaters, and motions of the structure with air flow velocities are investigated. In summary, all numerical results are almost identical to the previous research considering air compressibility. Therefore, it can be concluded that this analysis not considering air compressibility in the air chamber is more efficient and practical method.

Characteristics and Policy Implications of Private Development Parks in Japan (일본 민설공원 제도의 특성과 시사점)

  • Kim, Hyun
    • Journal of the Korean Institute of Landscape Architecture
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    • v.44 no.1
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    • pp.119-128
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    • 2016
  • Urban park planning has become difficult due to the lack of municipal funds. Thereupon, a special scheme was imposed for city park planning. Since then, a legal amendment was made for economical improvement and more active participation. However, there are a lot of questions about whether it was a suitable direction for parks and where it should be emphasized for public interest. Base on these concerns, this study examined the basis and characteristics of location, creation, and maintenance of private development parks in Japan, which was the policy model of Korean private parks. Location and space planning of private development parks was made up considering an effective green network and disaster prevention function, and a minimum area was about 1.42ha. The minimum area, 1ha, was established on the basis of considering realistic possibilities, disaster protection, and universal validity. It was also amended to consider the standard of type two mid- to high-rise exclusive residential areas and consultation with regional governance. Finally, it was built on the lowest limit of ordinance of the relevant city; for example, 100% of the floor area ratio, 30% of the building coverage ratio, and the maximum height of 11 stories, etc. For maintenance, private and public sectors were working together. Maintenance fees for 35 years (based on $300yen/m^2$ per month) were paid en bloc by the licensee. However, the city was paid for facilities that accompanied excessive maintenance costs. Meanwhile, it seemed difficult to introduce attractive profit facilities because of the limitations in location, usage permission, and introduction equipment; furthermore, there were problems with management authority, and the burden of expenses was deducted. For creating private Korean parks, this study suggested that we should build priority of creating city parks and select appropriate locations first; also, we need to make criteria for location, creation, and standard management rules that are relevant to the whole nation of Korea.

Recent Mortality Trends in Korea (최근(最近) 한국인(韓國人)의 사망력(死亡力) 경향(傾向)에 관(關)한 고찰(考察))

  • Kim, Il-Soon;Lee, Dong-Woo
    • Journal of Preventive Medicine and Public Health
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    • v.2 no.1
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    • pp.61-76
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    • 1969
  • A review has been made of mortality trends in Korea from 1958 to 1967 analyzing the data by sex, age and cause of death. The crude death rates and age specific death rates were estimated by the model of N. Keyfitz life table which had been developed by the data of the 1960's national census. The cause specific death rates shown in this article are based on the following: all deaths occurring in the death-registration are expressed as a numberator, while the denominator was estimated from the regular national census data by interpolation method. It is estimated that only an average of about 40% of deaths which occurred during a year were registered during 1958 to 1967. The validity and the reliability of the diagnosis of causes of death seem to be extremely poor in this country. Therefore the cause specific death rates in this article are aimed to reveal trends of causes of registered death ana not for the actual level of death rates. For 10 years very interesing mortality trends were observed : 1. The trend in the crude death rates was downward slowly. 2. The estimated death rate for the infant in 1960 was still high up to 100 per 1,000. 3. The rates for mortality attributed to such infectious diseases as pneumonia, bronchitis, gastroenteritis and measles decreased an average 40-60%. 4. The death rates for over-all tuberculosis decreased only 9.8%. 90% of the decrease was contributed by those in the less-than-15 year age group. 5. The death rates for chronic diseases, such as vascular diseases affecting the central nervous system, malignant neoplasm, major heart diseases and all accidents rose about 40-60%. 6. The rank order of the 10 leading causes of death showed large changes over the years, except for pneumonia and tuberculosis which occupyed 1st and 2nd places respectively. Vascular diseases affecting the central nervous system moved from 5th to 3rd place and malignant neoplasm from 6th to 4th place, The major heart diseases moved from 10th to 6th place and all accidents from 10th to 7th place. On tile other hand, gastroenteritis moved from 3rd to 5th place and influenja from 4th to 8th place.

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Reliability Estimation of High Voltage Ceramic Capacitor by Failure Analysis (고압 커패시터의 고장 분석을 통한 신뢰도 예측)

  • Yang, Seok-Jun;Kim, Jin-Woo;Shin, Seung-Woo;Lee, Hee-Jin;Shin, Seung-Hun;Ryu, Dong-Su;Chang, Seog-Weon
    • Journal of the Korean Society for Nondestructive Testing
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    • v.21 no.6
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    • pp.618-629
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    • 2001
  • This paper presents a result of failure analysis and reliability evaluation for high voltage ceramic capacitors. The failure modes and failure mechanisms were studied in two ways in order to estimate component life and failure rate. The causes of failure mechanisms for zero resistance phenomena under withstanding voltage test in high voltage ceramic capacitors molded by epoxy resin were studied by establishing an effective root cause failure analysis. Particular emphasis was placed on breakdown phenomena at the ceramic-epoxy interface. The validity of the results in this study was confirmed by the results of accelerated testing. Thermal cycling test for high voltage ceramic capacitor mounted on a magnetron were implemented. Delamination between ceramic and epoxy, which might cause electrical short in underlying circuitry, can occur during curing or thermal cycle. The results can be conveniently used to quickly identify defective lots, determine $B_{10}$ life estimation each lot at the level of inspection, and detect major changes in the vendors processes. Also, the condition for dielectric breakdown was investigated for the estimation of failure rate with load-strength interference model.

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The Factors Related to the Intention of Hospital Pharmacists for taking the Role of a Preceptor (병원약국 실무실습 교육 제공 의도에 대한 영향요인)

  • Han, Julie;Nam, Jina;Bang, Joon Seok;Cho, Eun
    • Korean Journal of Clinical Pharmacy
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    • v.25 no.4
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    • pp.238-245
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    • 2015
  • Background: Pharmacy schools newly adopted a 6-year program strengthening clinical knowledge since 2011 in Korea. The clinical training under the guidance of preceptors at hospital sites is a requisite for pharmacy students during the last year of undergraduate course. It has been rarely studied on the hospital pharmacists' perspective regarding being a preceptor or teaching pharmacy students. Objectives: This study aimed to examine the hospital pharmacists' intention toward student training and to identify the relevant factors among the individual pharmacists' characteristics and working environment within the theoretical frame of the Theory of Planned Behavior (TPB). Method: A mail-survey was conducted for pharmacists working in tertiary hospitals in Seoul and Incheon. The survey questionnaire consisting of 131 questions with a 5-likert scale was developed for investigating pharmacists' attitude, subjective norm, perceived behavioral control and the intention to teach pharmacy students as well as other demographic variables. To estimate the construct validity of components, factor analysis was conducted and Cronbach's alpha was calculated to estimate the reliability of the observed variables. Statistical analyses of one-way variance analysis and multiple regression analysis were performed using SPSS 18.0. Results: The survey response rate was 53% (116/210) and the three constructs of attitude (r = .519), subjective norm (r = .233) and perceived control (r = .392) have appropriate correlations with the intention, proving the appropriateness of using the TPB model. Pharmacists working in inpatient (mean = 3.45) and outpatient clinics (mean = 3.34) generally showed positive intention for teaching. The attitude (${\beta}=.432$, p < 0.01) and perceived control (${\beta}=.270$, p < .01) constructs were significant predictors of the intention. Both age (r = 0.246, p = 0.017) and length of career (r = 0.310, p = 0.002) were positively related with the perceived control. Conclusion: Hospital pharmacists showed generally positive intention to provide student training in spite of the concern on their limited perceived behavioral control. Future research to find the actual barriers pharmacists faced in educating students need to be conducted.