• 국제초고층학회논문집
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• 제10권1호
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• pp.73-83
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• 2021

The door open time, resulting from occupants evacuating from apartments, is an important parameter when assessing the performance of smoke ventilation systems in high-rise apartment buildings. However, the values recommended in UK design guidance appear to have limited substantiation. Monte Carlo simulations have been carried out considering variabilities in door swing time, flow rate and number of occupants. It has been found that the door open time can be represented by a lognormal distribution with a mean of 6.6, 8.7 and 11.1 s and a standard deviation of 1.7, 3.2 and 4.7 s for one, two and three-bedroom apartments, respectively. For deterministic analyses, it is proposed that the 95th percentile values may be adopted in line with recommended practice for other fire safety design parameters such as fuel load density and soot yield, giving door open times of 10 s to 19 s, depending on the number of bedrooms.

• Steel and Composite Structures
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• 제48권6호
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• pp.709-725
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• 2023

This paper uses a new type of deformation theory to establish the free vibration and static buckling equations of nanoplates resting on two-parameter elastic foundations, in which the flexoelectric effect is taken into account. The proposed approach used in this work is not only simpler than other higher-order shear deformation theories but also does not need any shear correction coefficients to describe exactly the mechanical responses of structures. The reliability of the theory is verified by comparing the numerical results of this work with those of analytical solutions. The results show that the flexoelectric effect significantly changes the natural frequency and the critical buckling load of the nanoplate compared with the case of neglecting this effect, especially when the plate thickness changes and with some different boundary conditions. These are new results that have not been mentioned in any publications but are meaningful in engineering practice.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• 제28권2호
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• pp.70-83
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• 2017

The objective of this review is the revision of the Korean practice parameters for the pharmacological treatment of attention-deficit hyperactivity disorder (ADHD) based on the change in the diagnostic system from DSM-IV-TR to DSM-5 and psychopharmacological developments. For the evidence-based approach, the authors conducted a review of the literature, including controlled clinical trials, studies of the side effects of drugs, toxicology and meta-analyses from the United States and Europe, as well as recent research conducted in Korea. The review committee composed of Korean experts on ADHD reviewed the revised parameters. This revised version reveals how to use central nervous system psychostimulants, non-stimulants such as atomoxetine and alpha2 agonists, and other medication for ADHD, and how to manage the adverse effects of such medication. At the end of this revised version, the authors propose recommendations for the pharmacotherapy of ADHD.

• 기본간호학회지
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• 제4권1호
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• pp.87-101
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• 1997

This Research is an attempt to find out what effects the resistance exercise program has on the rheumatoid arthritis patient's functional disability and biochemical parameters. The research took place from June to November 1996, and the target included an experimental group of 25 cases of rheumatoid arthritis and a control group of 26 cases of rheumatoid arthritis taken from the Anam Medical Center at Korea University. The resistance exercise program was executed on these patients five times a week during a period of eight weeks. Before and after the experiments, measurements of functional disability score, ESR, CRP, self-efficacy, and family support were taken and closely analysed. The results of this analysis are as follows : 1. After the experiment, the experimental group had less functional disabilities compared to the control group(t=9.11, P=0.0017). 2. After the experiment, the ESR of both the experimental and the control groups decrease, but there was not notable difference between the two groups(t=0.07, P=0.9546). 3. After the experiment, the CRP of both the experimental and the control groups decreased, with no significant different between them(t=0.53, P=0.6022). 4. After the experiment, the self-efficacy of the experimental group increased significantly compared to the control group(t=3.15, P=0.0042), but the self-efficacy had no effect on the actual practice of the program. 5. After the experiment, the family support of the experimental group was higher than of the control group(t=6.33, P=0.0013), but again the family support had no effect on the actual practice of the program. Judging from the results of these experiments, the resistance exercise program not only diminishes rheumatoid arthritis patients' functional disabilities, but also has a great influence on increasing their self-efficacy and family support. Concluding, in diminishing the functional disabilities of rheumatoid arthritis, the resistance exercise program would be appropriate nursing intervention.

• 가정과삶의질연구
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• 제23권2호
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• pp.77-91
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• 2005

The purpose of this study is to investigate general tendencies in credit card use, and determine the causes of the use of cash advance service and deferred payment among college students. Socio-demographic variables(gender, year in college, allowance, family income, parents' education and occupation, having taken a personal financial management course), knowledge and attitudes toward credit card, and financial management practices were incorporated as antecedent variables. Logistic regression analysis and multiple regression analysis were conducted to test the hypotheses. The results were as follows ; First, $32\%$ of the college students with no regular income experienced deferred payment, and $60.4\%$ of them had used a cash advance service. Second, the frequency and amount of cash advance service use were affected by family income, financial practices, and allowance. The financial practice as a parameter was affected by their completion of a personal finance course and their allowance. Third, deferred payment of credit was affected by their knowledge on credit cards and their financial practices. The financial practices as a parameter were affected by the family income and their completion of a personal finance course, and the knowledge on credit cards was affected by gender. Lastly, implications and suggestions for credit card use behavior research and consumer credit education are discussed in this article.

• 대한토목학회논문집
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• 제14권4호
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• pp.887-896
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• 1994

일반적으로 다목적댐을 대상으로 하는 최적운영모형에 이용되는 각종 추계학적 모의 모형은 주로 저수지 유입량을 모의하기 위한 모형이며, 시스템으로부터의 용수수요량과 같은 변수들은 일정한 값을 가진다고 가정한다. 그러나 특수한 목적의 저수지의 경우 시스템 구성인자들 사이에 어떤 상관성이 있다면, 이를 이용하여 각 변수들의 관계를 도출한 후, 시스템을 구성하는 것이 바람직하다. 본 연구에서는 농업용수 공급을 목적으로 하는 다목적댐을 대상으로 강우 및 기상조건에 영향을 받는 순별 저수지 유입량과 농업용수 수요량을 각각 일정변수 주기성 자기회귀모형과 일정변수 주기성 다변량 자기회귀모형을 이용하여 모의발생 하였다. 유도된 모형은 각 변수의 통계화적 특성을 잘 나타내며, 농업용수 수요량의 경우 전(前) 시간의 수요량보다는 현재 운영기간(순(旬))의 저수지 유입량과의 상관관계에 더 큰 영향을 받는 것으로 나타냈다.

• Annals of Clinical Neurophysiology
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• 제4권2호
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• pp.108-113
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• 2002

Background and Objective : Carpal tunnel syndrome (CTS) is the most common mononeuropathy encountered in clinical practice. No single procedure or group of procedures has demonstrated adequate sensitivity. F-wave study in CTS is very rarely reported. To determine the diagnostic usefulness of new parameters of F-wave and comparative study of F-wave parameters of median and ulnar nerves in patients with CTS. Methods : F-wave responses of median and ulnar nerves were analyzed from 27 patients with clinically diagnosed CTS and 22 age and gender-matched normal control. Conventional F-wave parameters were studied. Also, the usefulness of new parameters such as mean and maximal ulnar-median F-wave latency differences, ulnar-median F-wave persistence and chronodispersion differences, median/ulnar F-wave amplitude ratio, and F-wave conduction velocity (FCV) using mean and maximal latency were assessed. Results : Compared with controls, median F-wave minimal, maximal and mean latencies, mean F-wave amplitude/M-wave amplitude, minimal, mean and maximal ulnar-median F-wave latency differences, and FCVs using minimal, maximal and mean latency were significant (P<0.05~0.001). Median F-wave minimal, maximal and mean latencies, mean ulnar-median F-wave latency difference, and FCVs using minimal, maximal and mean latency showed high sensitivity and specificity. Mean ulnar-median F-wave latency difference and FCVs using maximal and mean latency were new parameters. Conclusion : New F-wave parameter including mean ulnar- median F-wave latency difference and FCVs using maximal and mean latency may be a useful to assess the CTS. Also, median F-wave minimal, maximal and mean latencies, and FCV using minimal latency may be included in routine diagnostic tests in CTS.

• 한국융합학회논문지
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• 제6권4호
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• pp.121-126
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• 2015

한국청소년패널(2008)의 중2 패널 5차년도 자료를 가지고 기술통계 분석과 회귀분석을 실시하여 가족의 기능적 결손이라는 위험상황에서 위험요인, 보호요인, 심리적응 간의 관계와 보호요인의 매개효과의 기제를 검증하고, 심리적응 수준이 높은 청소년을 보호해주는 보호요인을 분석하는 데에 그 목적이 있다. 분석방법으로는 대상자의 빈도분석과 개인특성에 따른 차이를 알아보기 위해 PASW(Predictive Analytics Software) 18.0을 이용해 t검증을 실시하였다. 또한 적응에 대한 보호요인의 작용 검증을 위하여 위계적 회귀분석을 실시하여 매개효과를 검증하였다. 연구결과 사회복지실천 현장에서 청소년의 위험요인에 초점을 맞추기보다는 위험요인을 완화시키는 과정이나 보호요인에 초점을 맞춤으로써 위험요인에 노출된 청소년을 바라보는 시각을 전환시킬 수 있으며 이들에 대한 개입도 달라질 것으로 판단된다. 사회복지실천 현장에서 청소년의 위험요인에 초점을 맞추기보다는 위험요인을 완화시키는 과정이나 보호요인에 초점을 맞춤으로써 위험요인에 노출된 청소년을 바라보는 시각을 전환시킬 수 있다. 또한, 가족의 기능적 결손이라는 어려움을 경험하는 청소년을 대상으로 사회복지 실천적 개입 방향을 마련 할 수 있는 기초를 마련한 것으로 판단된다.

• Geomechanics and Engineering
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• 제36권5호
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• pp.465-474
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• 2024

Uniaxial compressive strength (UCS) is a critical geomechanical parameter that plays a significant role in the evaluation of rocks. The practice of indirectly estimating said characteristics is widespread due to the challenges associated with obtaining high-quality core samples. The primary aim of this study is to investigate the feasibility of utilizing the gene expression programming (GEP) technique for the purpose of forecasting the UCS for various rock categories, including Schist, Granite, Claystone, Travertine, Sandstone, Slate, Limestone, Marl, and Dolomite, which were sourced from a wide range of quarry sites. The present study utilized a total of 170 datasets, comprising Schmidt hammer (SH), porosity (n), point load index (Is(50)), and P-wave velocity (Vp), as the effective parameters in the model to determine their impact on the UCS. The UCS parameter was computed through the utilization of the GEP model, resulting in the generation of an equation. Subsequently, the efficacy of the GEP model and the resultant equation were assessed using various statistical evaluation metrics to determine their predictive capabilities. The outcomes indicate the prospective capacity of the GEP model and the resultant equation in forecasting the unconfined compressive strength (UCS). The significance of this study lies in its ability to enable geotechnical engineers to make estimations of the UCS of rocks, without the requirement of conducting expensive and time-consuming experimental tests. In particular, a user-friendly program was developed based on the GEP model to enable rapid and very accurate calculation of rock's UCS, doing away with the necessity for costly and time-consuming laboratory experiments.

• 대한방사선치료학회지
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• 제15권1호
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• pp.19-27
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• 2003

I. 목적 Total Body Irradiation(TBI)와 Half Body Irradiation(HBI), Non-Hodgkin's lymphoma, E-Wing's sarcoma, lymphosarcoma, neuroblastoma 등의 특수한 경우에 넓은 광자선 조사면($40{\times}40cm2$ 이상)이 임상적으로 사용될 수 있다. 넓은 광자선 조사면의 선량분포는 매번 실제 측정 대신 좁은 광자선 조사면 (표준 SSD 100cm, 조사면의 크기 $40{\times}40cm2$ 미만)에서 얻은 측정결과를 이용하여 보정할 수 있으나, 단 순한 계산에 의한 방법만으로는 산란 방사선의 여러 가지 요인에 의한 실제 신체 각 부위의 선량 및 그 균일성을 알기는 힘들다. 본 연구에서는 치료거리 증가에 따른 넓은 광자선 조사면의 기본 parameter(PDD, TMR, Output, Sc, Sp)를 측정하고, 좁은 광자선 조사면에서 얻은 측정결과와 비교하여 그 차이를 확인해 보고 실제 적용여부를 알아보고자 한다. II. 대상 및 방법 표준 SSD 100cm에서 Multidata water phantom을 이용하여 조사면의 크기 변화에 따라 기본parameter(PDD, TMR, Output, Sc, Sp)를 측정하였다. 먼저 SSD 180cm에서(phantom이 치료실 바닥으로 수직방향) 조사면 증가에 따른 기본 parameter를 측정하였고, SSD 350cm에서(phantom이 치료실 벽면으로 수평방향이고 horizotal beam의 측정이 가능한 mylar를 가진 small water phantom을 이용) 같은 방법으로 측정하여 서로 비교해보았다. III. 결과 및 결론 SSD 180cm과 350cm에서 측정한 parameter들이 표준 선량측정 자료와 비교해서 오차범위가 실험적 오차에 있을 정도로 큰 차이가 없었음을 알 수 있었다. 정확한 자료를 얻기 위해 anthropomorphous phantom에서 선량측정을 하거나 이런 목적을 위해 특별히 고안된 unlimited phantom을 이용한 절대값을 얻을 수 있는 선량 측정이 요구된다. 부가적으로 작은 부피의 ionization chamber 사용과 넓은 조사면에 의한 cable과 stem effect를 고려해야 할 필요가 있다.