• 전력전자학회논문지
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• 제8권1호
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• pp.89-97
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• 2003

PWM 인버터에 의해 구동리근 유도전동기에 발생되는 고주파 커먼 모드 전압은 전도성 EMI, 전통기 접지전류, 베어링 전류 및 다른 원치 않는 결과의 주원인이 된다. 인버터 제어의 무효벡터 스위칭 상태는 나머지 유효벡터 스위칭 상태에 비교하여 큰 커먼 모드 전압을 일으킨다. 그러므로 이 논문은 커먼 모드 전압을 완화하는 스위칭기법을 다룬다. 즉 정현파 PWM 기법을 기본으로 한 커먼 모드 전압 제거방법을 제안하였다. PWM 신호는 각자의 정현과 기준신호와 120$^{\circ}$위상차가 나는 3개의 캐리어 파형과 비교하여 발생된다. 시뮬레이션과 실험적 결과는 제안된 PWM 기법에서 커먼 모드 전압이 종래의 PWM 기법보다 약 66% 더 저감됨을 보였다.

• KIEAE Journal
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• 제9권2호
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• pp.9-16
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• 2009

Modern public museums are expanding its role as general cultural facilities. Therefore, the museums that are equipped with convenient and physical environmental features for all ages and types of users are needed. The purpose of this research is to evaluate the application of universal design in common space of the museums and to recommend a set of environmental improvement plans based on which various types of users can decide their choice of museums based on available data on the museums. The scope of this research was limited to seven major public museums located in Seoul, Korea. The spatial scope that was set for this research was common space of the public museums and the scope of the content was about the applicability of universal design. As a result of the research, three major conclusions were reached. First, the application of universal design toward common space in the public museums currently was not prevalent. Second, constant management and application development of universal design are needed. Third, as museums' primary roles and functions become more diverse, a direct application of delicate universal design is a necessary prerequisite to accommodate and fulfill users' needs.

• Clinical and Experimental Pediatrics
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• 제59권8호
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• pp.313-318
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• 2016

Complementary and alternative medicine (CAM) is a phrase used to describe additional health care methods such as mind/body practices and natural products not regarded as treatments by conventional medicine. The use of CAM in children with common neurologic diseases is more frequent than its use in healthy children (24%-78% vs. 12%). However, less than half of patients report such use to their physicians. The preferred modalities of CAM vary in different countries due to their different cultures and traditions. The most common factor significantly associated with the use of CAM is parental CAM use in most studies. The frequency of the use of CAM in children and adults with neurologic diseases is similar, and both rates are higher than the rates in those without these conditions. The preferred modalities of CAM in adults are diverse, and megavitamins and mind/body therapy (prayer and chiropractic care) are included. The most common factor significantly associated with the use of CAM in adults with neurologic diseases is high educational level. Physicians need to be concerned with patients' use of CAM and provide correct information about CAM so that patients may make the right decisions. Further study is needed to determine the evidence-based efficacy of CAM use in children with common neurologic diseases.

• Asian Pacific Journal of Cancer Prevention
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• 제17권9호
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• pp.4363-4365
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• 2016

Background: The complex anatomy of the pancreaticobiliary duct was crucial in management of pancreatic and biliary tract disease. Materials and Methods: Fresh specimens of pancreas, common bile duct (CBD), and duodenum were obtained en bloc from autopsies of 160 patients. Results: Ninety-three male and 67 female patients were included. The length of the pancreas ranged from 9.8-20 cm (mean, 16.20 +/- 1.70 cm). The intrapancreatic portion of the CBD showed patterns of three types: most common (85.30%) was type A, in which the anterior surface of the common bile duct was totally covered, while its posterior surface was partially covered, by the pancreatic parenchyma. On dissection of the accessory duct of Santorini, the accessory duct was traceable to the duodenal wall in 67.6%. The anatomy of the Wirsung-choledochus confluence was grouped into five different types. The common channel was found in 75.60% and its length varied from just a common junction (so-called "V-type" anatomy) to 15 mm (Y-type-b). Separate papillae (so-called "II-type") were found in 15.3% of specimens. Conclusions: Several important points regarding the anatomy of the pancreaticobiliary junction and pancreatic ductal system were illustrated in this study.

• Journal of Ecology and Environment
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• 제36권3호
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• pp.193-204
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• 2013

Altitudinal patterns of plant species richness and the effects of area, the mid-domain effect, climatic variables, net primary productivity and latitude on observed richness patterns along the ridge of the Baekdudaegan Mountains, South Korea were studied. Data were collected from 1,100 plots along a 200 to 1,900 m altitudinal gradient on the ridge. A total of 802 plant species from 97 families and 342 genera were recorded. Common and rare species accounted for 91% and 9%, respectively, of the total plant species. The altitudinal patterns of species richness for total, common and rare plants showed distinctly hump-shaped patterns, although the absolute altitudes of the richness peaks varied somewhat among plant groups. The mid-domain effect was the most powerful explanatory variable for total and common species richness, whereas climatic variables were better predictors for rare plant richness. No effect of latitude on species richness was observed. Our study suggests that the mid-domain effect is a better predictor for wide-ranging species such as common species, whereas climatic variables are more important factors for range-restricted species such as rare species. The mechanisms underlying these richness patterns may reflect fundamental differences in the biology and ecology of different plant groups.

• 한국주거학회논문집
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• 제14권5호
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• pp.1-9
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• 2003

The purpose of this study is to consider the community design applications in the senior collective housing in Hyogo Prefecture, Japan. It was performed by two programs, application program and space design program. The former is focused on the participation of residents to the planing and design process, sharing, community activity, social interaction, and management by residents. The latter is focused on the common space(room) design. It was also performed by literature review, observation, and interview. The findings for the community design as an application program in SCH are almost the same with those in CH. But, the level of common meal and common laundry in SCH is lower than that of CH. And space design program is focused on the location and scale of common space(room) which is related to the number of users. As a result, the positive possibilities of SCH as a new residential type for the self-reliant seniors can be confirmed. The difference of community design application between CH and SCH is caused by various factors such as senior's health conditions, economic factors, and Japanese life style.

• 항공우주기술
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• 제8권2호
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• pp.170-178
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• 2009

위성 개발 및 운영의 주체가 달라서 이중으로 소모되는 에너지를 줄이기 위해 공통지상 시스템의 통합 개발이 절실히 필요하다. 위성의 개발, 시험, 통합, 발사, 궤도 운영, 임무 수행의 전주기를 아우르는 공통지상시스템을 개발하기 위해서는 모든 단계에서 사용될 수 있는 언어를 개발해야 한다. 이를 위해 위성 시험운영언어의 유럽표준인 PLUTO와 가장 대표적인 언어중 하나인 STOL과 ELISA 및 PIL과 현재 항공우주연구원 AIT의 위성 시험 언어인 ATS와 지상국 운영시스템인 MCE를 자세히 분석하고, 이를 토대로 통합 절차서 언어 개발을 위한 설계 요건들을 제안한다.

• 대한기계학회논문집A
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• 제31권3호
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• pp.355-364
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• 2007

Multidisciplinary design optimization based on independent subspaces (MDOIS) is a simple and practical method that can be applied to the practical engineering MDO problems. However, the current version of MDOIS does not handle the common design variables. A new version of MDOIS is proposed and named as MDOIS/2006. It is a two-level MDO method while the original MDOIS is a single-level method. At first, system analysis is performed to solve the coupling in the analysis. If the termination criteria are not satisfied, each discipline solves its own design problem. Each discipline in the lower level solves the problem with common design variables while they are constrained by equality constraints. In the upper level, the common design variables of related disciplines are determined by using the optimum sensitivity of the objective function. To validate MDOIS/2006, mathematical problem and NASA test bed problem are solved. The results are compared with those from other MDO methods. Finally, MDOIS/2006 is applied to flow patterner design and shows that it can be successfully applied to the practical engineering MDO problem.

• 한국수산과학회지
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• 제37권6호
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• pp.492-497
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• 2004

Waste concentration and waste generation rate in seawater aquaria by common conger (Astrocongey myriaster) and olive flounder (Paralichyhus olivaceus) were investigated. The initial fish density of common conger and olive flounder were $3{\%}\;and \;2.8{\%}$ of total weight of aquarium water, respectively Wastes in the seawater aquaria, such as protein, total suspended solid (TSS), ammonia, turbidity and chemical oxygen demand (COD) increased with days after stocking. Protein generation rate of common conger increased until 1 day after stocking while that of olive flounder increased until 3 days. The average protein generation rates of common conger and olive flounder were $0.28g/kg{\cdot}day\;and\;0.21g/kg{\cdot}day$, respectively. The trends of other waste generation rate were similar to protein generation rate.

• 한국수산과학회지
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• 제51권3호
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• pp.338-343
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• 2018

Recently, commercial catches of the common squid Todarodes pacificus have dramatically decreased in Korean and Japanese waters. The relationship between common squid catches and environmental factors was investigated using squid catches, climate indices and observed seawater temperatures in Korean waters. Common squid consist of three spawning stocks: autumn, winter, and summer. The autumn stock is the largest in Korea, and its main fishing season appears to have shifted from September in the 1980s to October in the 1990s. We observed negative correlations between the spring Southern Oscillation Index and Korean catches and between the winter Pacific Decadal Oscillation and Japanese catches. Despite global warming, no conspicuous increases in October seawater temperatures have been observed at 10 and 50 m in Korean waters since the mid-1900s. Instead, the 50 m water layer of the East Sea appears to be gradually cooling. Moreover, temperatures at 50 m in the East Sea and the South Sea were significantly negatively correlated with squid catches in Korea and Japan, respectively. Our preliminary analysis indicates a link between climate change, seawater temperature, and squid catches in Korean waters, which helps to inform the direction of subsequent research to identify the cause of rapid decreases in this squid resource.