• 한국해안해양공학회지
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• 제3권4호
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• pp.217-222
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• 1991

동해안 방파제의 대표적 단면형태인 투수성 사석방파제에서 cap concrete의 형상의 파랑의 투과 및 쇄파에 미치는 효과를 구명하기 위하여 3가지 형태의 상부구조물에 대하여 항내 전달파고에 관한 모형실험을 2차원 조파수조에서 실시하였다. 실험결과, 제방전면 수심이 크고 입사파 주조가 길수록 항측에 일정간격의 apron을 설치한 유공의 경우 항측에 apron을 설치한 무공의 경우, 그리고 apron이 없는 무공의 경우 순으로 항내전달 파고의 감소효과가 우수한 것으로 나타났다. Apron을 설치한 유공 cap concrete 구조가 우수한 것을 수평방향으로 투과되거나 월파되는 파랑에너지가 상부구조물에 설치된 소산공과 apron에 의해 일부 유실되어 항쪽으로 전달되는 에너지가 감소하기 때문이다.

• 한국물환경학회지
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• 제24권4호
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• pp.452-457
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• 2008

Nonpoint source (NPS) pollution is caused by rainfall moving over and through the ground. As the runoff moves, it picks up and carries away various pollutants from NPS. The discharge pattern of NPS pollutant loads is affected by the distribution of the rainfall during the year. This study analysed relationship between the rainfall event and the stream flow rate, and estimated the rainfall discharge ratio on the specific design flow which can be used as nonpoint discharge coefficient for the estimation of NPS pollution load. It is considered that nonpoint discharge coefficient can be effectively used for the calculation of NPS pollution load at the time of water quality modelling for the management of Total maximum daily load (TMDL).

• 한국농공학회지
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• 제17권3호
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• pp.3872-3877
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• 1975

This study was conducted to examine the effects of the change of cap hole diameter and pressure on the travelling distance and the sprayed particle size for the medium range nozzle. The results of this study are summarized as follows; 1) The effective travelling distance was about from 1 meter to 8 meters and centro-position of the travelling distance was about 3 or 5 meters. 2) Main effect of change of cap hole diameter for the travelling distance was a slight convex quadratic curve. 3) Main effect of change of pressure increased linearly, its increasing rate about 1.6 was large. 4) Sizes of sprayed particles were less than 250${\mu}$ generally and the sizes decreased according to the increasing of travelling distance. 5) Changes of diameter of sprayed particles by cap hole diameter increased in accordance with increasing of cap hole diameter. 6) Changes of diameter of sprayed particles by the groove depth of swirl plate was very slight.

• Tuberculosis and Respiratory Diseases
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• 제76권2호
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• pp.66-74
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• 2014

Background: The increasing number of outpatients with multidrug-resistant (MDR) pathogens has led to a new category of pneumonia, termed healthcare-associated pneumonia (HCAP). We determined the differences in etiology and outcomes between patients with HCAP and those with community-acquired pneumonia (CAP) to clarify the risk factors for HCAP mortality. Methods: A retrospective study comparing patients with HCAP and CAP at Jeju National University Hospital. The primary outcome was 30-day mortality. Results: A total of 483 patients (208 patients HCAP, 275 patients with CAP) were evaluated. Patients with HCAP were older than those with CAP (median, 74 years; interquartile range [IQR], 65-81 vs. median, 69 years; IQR, 52-78; p<0.0001). Streptococcus pneumoniae was the major pathogen in both groups, and MDR pathogens were isolated more frequently from patients with HCAP than with CAP (18.8% vs. 4.9%, p<0.0001). Initial pneumonia severity was greater in patients with HCAP than with CAP. The total 30-day mortality rate was 9.9% and was higher in patients with HCAP based on univariate analysis (16.3% vs. 5.1%; odds ratio (OR), 3.64; 95% confidence interval (CI), 1.90-6.99; p<0.0001). After adjusting for age, sex, comorbidities, and initial severity, the association between HCAP and 30-day mortality became non-significant (OR, 1.98; 95% CI, 0.94-4.18; p=0.167). Conclusion: HCAP was a common cause of hospital admissions and was associated with a high mortality rate. This increased mortality was related primarily to age and initial clinical vital signs, rather than combination antibiotic therapy or type of pneumonia.

• JSTS:Journal of Semiconductor Technology and Science
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• 제2권2호
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• pp.141-146
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• 2002

The effect of the wide-bandgap Schottky barrier enhancement cap layer on the performance of metal-semiconductor-metal photodetectors (MSMPD's) is presented. Judged by the dc characteristics, no considerable increase in recombination loss of carriers is resulted by the incorporation of the cap layer. However, about 45% of the detection efficiency is lost for the cap-layered MSMPD's even with a graded layer incorporated under pulse operation, and it was found to be due mainly to the capturing and slow release of the photocarriers at the heterointerface. The loss mechanism of the pulse detection efficiency is believed to be responsible for the intersymbol interference and the increased bit-error-rate (BER) observed in MSMPD's when used with a high bit rate pseudo-random-bit-stream (PRBS) data pattern.

• 한국농공학회지
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• 제15권3호
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• pp.3053-3058
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• 1973

1. This study was conducted to examine the effects of change of the short range nozzle hole on the travelling distance. The results of this study are summarized as follows; a) Effect of change of the cap hole diameter on the travelling distance of sprayed particles was generally a linear, the increasing rate was about 0.27. b) When the difference between the sectional area of cap hole and that of grooves of swirl plate, was small the travelling distance was decreased by the decreasing of spraying speed at cap hole. 2. This study was conducted to examine the effects of change of the short range nozzle hole on the size of spraying particles. The results of this study are summarized as follows; a) The diameter of sprayed particles on travelling distances in the short range nozzle did not coincide with the kinetic energy principle derived from the momentum and the resistance. b) The average diameter of sprayed particle between 1m and 3m in which amount of sprayed particle was particularly a great deal, was big, because that some of sprayed particles were absorbed each other on the way to fall c) Effect of increase of cap hole diameter was generally enlarged the average diameter of sprayed particle with small rate.

• 한국물환경학회지
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• 제26권2호
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• pp.279-288
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• 2010

The water quality variations or changes are closely relevant to the characteristics of unit watersheds and have an effect on the attainment of their water quality goal. This study was conducted to analyze the water quality distribution and its change patterns of unit watersheds in Nakdong river basin. It revealed that 25 unit watersheds out of 41 showed the normality in water quality. Most of unit watersheds had a considerable variation in water quality, especially in the season of spring and summer but a little in terms of flow rate. Annual relative differences in water quality ranged from 13.0 to 26.6% with the maximum of 75%. 28 unit watersheds (62%) had the tendency to decrease in water quality as the flow rate increased while 13 (38%) to increase. The extension of standard flow led to considerable differences in water quality depending on its ranges, which meant uncertainties might be included in the process of TMDL development. It is suggested that annual average flow rate should be chosen as a standard flow in the area where the water quality change has little relation to the flow rate.

• 한국산업보건학회지
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• 제31권4호
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• pp.353-366
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• 2021

Objectives: An appropriate level of cost support is being proposed to maximize the participation rate. In addition, as the amount of support is highly concentrated at the level of the limit under the current level of supports, the level of cost support is low when the actual level of cost of measuring the working environment exceeds the limit. This paper describes the adjustment of an appropriate cost support rate. Methods: First, this paper analyzes the current cost support status using data from the KOSHA. Second, an alternative for adjusting the cost support rate is presented in consideration of the incentive aspect. Third, we present simulation results for the average cost support rate, the impact of each alternative on finance, and more. Fourth, the most desirable adjustment method is presented after comparing and analyzing the results of various alternatives. Results: In this paper, we present a new scale model. This model is a mixture of flat-rate, fixed rate, and subside cap. It is expected that the new model will not only facilitate participation in businesses with low measurement costs, but also have the effect of controlling measurement costs for institutions that incur greater costs. It is also expected that setting a cap will have the effect of considering government finances and inducing excessively costly institutions to reduce costs. Thus, the new model is likely to be superior to others. If the fourth plan is applied to new businesses and the fifth plan is applied to sustainable businesses, the average cost support rates will be 87.68 percent and 65.18 percent, respectively, and the needed finances will be 2.5 billion won, 18.8 billion won, and 21.3 billion won in total. Conclusions: It seems most desirable to introduce a new model that combines flat-rate, fixed-rate, and subsidy cap systems and achieve an appropriate cost support rate through this model.

• Tuberculosis and Respiratory Diseases
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• 제71권5호
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• pp.335-340
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• 2011

Background: Community-acquired pneumonia (CAP) is an important cause of morbidity and mortality throughout the world in all age groups. Viral causes of CAP are less well characterized than bacterial causes. We analyzed the characteristics of hospitalized patients with CAP who had a viral pathogen detected by multiplex polymerase chain reaction (PCR). Methods: Multiplex real-time PCR was performed for respiratory viruses in samples collected from 520 adults who developed CAP at Chungnam National University Hospital. Clinical, laboratory, and radiological features at presentation as well as other epidemiological data were analyzed. Results: Of 520 patients with CAP, a viral pathogen was detected in 60 (11.5%), and influenza A was the most common. The virus detection rate in patients with CAP was highest in November. Two or more pathogens were detected in 13 (21.7%) patients. Seven patients had severe disease and were administered in the intensive care unit. Most patients (49/60, 81.7%) had comorbidities. However, nine (15%) patients had no comorbidities, and their age was <60 years. The ground glass opacity pattern was the most common radiological feature. Seven (11.7%) patients died from CAP. Conclusion: Viral pathogens are commonly detected in patients with CAP, and a respiratory virus may be associated with the severity and outcome of pneumonia. Careful attention should be paid to the viral etiology in adult patients with CAP.

• 지적과 국토정보
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• 제47권2호
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• pp.159-174
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• 2017

오피스의 수급 불균형은 도시 성장을 약화시킨다. 오피스의 초과공급이 공실률을 높이고 임대료가 하락하는 등 시장의 불안정성을 키울 수 있기 때문이다. 또한 오피스의 초과수요가 기업의 임차비용을 상승시켜 도시의 산업 성장을 제한할 수 있다. 최근 대규모의 신규 공급이 서울 오피스시장의 변동성을 높였다. 그럼에도 불구하고 오피스 공급에 대한 연구는 미미한 실정이다. 따라서 본 연구는 서울 오피스 신규 공급의 영향요인을 확인하고 수급 불균형의 주요 원인인 시차를 고려하여 결정요인들의 동태적 구조적인 움직임을 분석하였다. 이를 위해 시계열모형인 벡터오차수정모형(VECM)을 활용하여 2003년부터 2015년까지 서울 오피스시장의 분기별 자료를 분석하였다. 분석결과, 서울 오피스 신규 공급에 영향을 주는 요인은 1분기 전 오피스 신규 공급량(-), 1분기 전 오피스 고용자 수(+), 2분기 전 이자율(+), 1분기 전 cap rate(-), 2분기 전 cap rate(-)으로 확인되었다. 이를 바탕으로 영향요인들 간의 시간에 따른 상호의존성과 변동에 따른 상대적 기여도를 분석한 결과, 이자율과 cap rate은 신규 공급량에 단기적인 영향을 미친 반면 고용과 공실률은 장기적이고 지속적인 영향을 미쳤다. 따라서 예측 가능한 오피스 시장 전망을 위해서는 이러한 오피스 신규 공급 영향요인에 대한 공신력 있는 자료 구축이 필요하고 지속적인 모니터링이 필요하다. 오피스는 기업과 산업의 성장을 이끄는 핵심적인 도시인프라이기 때문이다.