• 한국정보과학회논문지:데이타베이스
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• 제35권3호
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• pp.218-230
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• 2008

시간지원 데이타베이스 시스템에서의 시간 집계 연산은 일반적인 집계 연산의 확장으로써, 집계의 범위 조건에 '시간'을 포함한다. 시간 집계 연산은 이력 데이타 웨어하우스, 전화 기록 관리(CDR) 등에 유용하다. 본 논문에서는 질의 조건에 여러 개의 선택 프레디키트들을 포함하는 시간 집계 연산을 효율적으로 처리하기 위한 자료 구조인 ITA-tree를 제안하고, 이를 이용한 시간 집계 처리 기법을 제안한다. ITA-tree에서는 레코드의 시간 구간을 T-value라는 하나의 값으로 변환한 후, $B^+$-tree와 비슷하게 이 값을 이용하여 색인을 생성한다. 또한, 많은 레코드가 동일한 T-value 값을 가지게 되는 핫-스팟 문제를 위해 개선된 ITA-tree인 eITA-tree를 제안한다. 본 논문에서는 제안된 기법들의 성능을 분석과 실험을 통해 비교한다.

• 한국의료질향상학회지
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• 제22권2호
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• pp.15-25
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• 2016

Objectives: In this study, we examined the validity of Clostridium difficile culture results as a proxy measure of Clostridium difficile infection, and inferred the epidemiologic characteristics of Clostridium difficile infection by tracking the trends of Clostridium difficile culture results. Methods: We reviewed the medical records to figure out the actual possibilities of Clostridium difficile infection of those with positive or negative results of Clostridium difficile culture during the time span from January 2012 to March 2012. We calculated the positive and negative predictive value of Clostridium difficile culture results for Clostridium difficile infection. Furthermore, epidemiologic characteristics of Clostridium difficile infection in a tertiary general hospital in 2012 were analyzed. Result: The estimated positive predictive value of Clostridium difficile culture tests for Clostridium difficile infection was 100%, and the estimated negative predictive value was around 94.4~99.3% depending on the cutoff value of possibility of Clostridium difficile infection. A total of 622 cases were identified as Clostridium difficile infection in a tertiary general hospital in 2012 and there were 4.9 patients with Clostridium difficile infection per 1,000 inpatients. Conclusion: In conclusion, we identified that Clostridium difficile culture results can be used as a proxy measure of Clostridium difficile infection.

• Clinical and Experimental Emergency Medicine
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• 제5권4호
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• pp.264-271
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• 2018

Objective For patients with acute myocardial infarction (AMI), symptoms assessed by emergency medical services (EMS) providers have a critical role in prehospital treatment decisions. The purpose of this study was to evaluate the diagnostic accuracy of EMS provider-assessed cardiac symptoms of AMI. Methods Patients transported by EMS to 4 study hospitals from 2008 to 2012 were included. Using EMS and administrative emergency department databases, patients were stratified according to the presence of EMS-assessed cardiac symptoms and emergency department diagnosis of AMI. Cardiac symptoms were defined as chest pain, dyspnea, palpitations, and syncope. Disproportionate stratified sampling was used, and medical records of sampled patients were reviewed to identify an actual diagnosis of AMI. Using inverse probability weighting, verification bias-corrected diagnostic performance was estimated. Results Overall, 92,353 patients were enrolled in the study. Of these, 13,971 (15.1%) complained of cardiac symptoms to EMS providers. A total of 775 patients were sampled for hospital record review. The sensitivity, specificity, positive predictive value, and negative predictive value of EMS provider-assessed cardiac symptoms for the final diagnosis of AMI was 73.3% (95% confidence interval [CI], 70.8 to 75.7), 85.3% (95% CI, 85.3 to 85.4), 3.9% (95% CI, 3.6 to 4.2), and 99.7% (95% CI, 99.7 to 99.8), respectively. Conclusion We found that EMS provider-assessed cardiac symptoms had moderate sensitivity and high specificity for diagnosis of AMI. EMS policymakers can use these data to evaluate the pertinence of specific prehospital treatment of AMI.

• 한국산학경영학회:학술대회논문집
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• 한국산학경영학회 2006년도 춘계학술발표대회 발표논문집
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• pp.171-190
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• 2006

도요타 자동차는 2005년도 결산 보고서에서 영업이익은 6년 연속, 순이익은 4년 연속 사상 최고치를 경신한 것으로 나타났다. 순이익은 전년도 보다 11% 증가한 1조 3000억 엔(약 11조 500억 원)에 달하는 것으로 보고 있다. 최고의 이익을 계속 갱신하면서 세계의 주목을 받고 있는 도요타 자동차는 낭비제거와 개선(改善)을 골자로 하는 생산방식의 강점을 보유하고 있다. 도요타 생산방식의 기본 사상은 낭비를 철저히 제거하여 생산성을 향상시킴으로 부가가치를 통한 이익을 창출하는 것으로, 이를 뒷받침 해주는 것이 "Just-in time" 과 " 사람 인(人)변의 자동화(自動化)라는 두 가지 기둥이다. 최근 한국의 제조기업 뿐만 아니라 서비스업종까지 도요타 생산 시스템을 재조명하여 자사에 적용하기 위한 많은 시도가 이어지고 있다. 도요타 생산방식의 이론의 고찰을 통하여 도요타 생산방식을 재정립하고, 실제로 도요타 생산방식이 적용되어진 사례연구를 통하여 우리의 기업환경에 적합하도록 활용할 수 있는지를 검토하고 연구 발전시켜야 한다.

• 한국지진공학회논문집
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• 제12권6호
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• pp.35-45
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• 2008

구조물의 응답에 대한 잔류변위의 영향을 평가하기 위하여, 초기 잔류변형이 있는 상태에서 작용하는 설계지진에 대한 좌굴방지 가새골조(BRBF)와 특수 모멘트골조(SMRF)의 응답을 평가하였다. 초기 잔류변형은 구조물에 두 가지 방법으로 적용하였다. 첫 번째 방법은 첫 지진에 대하여 구조물이 정지 상태에 도달한 이후 같은 크기의 지진을 적용하는 것이다. 두 번째 방법은 소요 잔류층간 변형이 발생할 때까지 일방향으로 가력한 다음 지진하중을 적용하였다. 해석결과에 따르면 초기 잔류층간변위는 BRBF와 SMRF의 응답에 큰 영향을 주었다. SMRF 시스템보다 BRBF의 응답이 초기 잔류변형에 크게 의존하였다. 그러므로 지진발생 이후 보수비용을 최소화하기 위하여 잔류층간변위를 줄이는 것이 필요하다.

• 생물환경조절학회지
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• 제19권4호
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• pp.223-228
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• 2010

Hosta 품종 중에서 관상가치가 있는 21종을 선정하여 절엽 소재로 개발하고자 2009년 7월 1일부터 8월 15일까지 광도 750Lux, 온도 $28{\pm}2^{\circ}C$, 습도 52% 의 실내 환경 조건에서 수명을 조사하였다. H. 'June'의 절엽 수명이 29일로 가장 길었으며 10일 이상 수명을 유지한 품종은 'Remember Me', H. lancifolia var. grandiflora, 'Grand Marquee', 'Dress Blue', 'Blue Dimples', 'Frosted Dimples' 'Birchwood Park's Gold', 'Krossa Regal', 'Paradise Power'였다. 이 10가지 품종의 특정은 엽록소 함량이 높고, 경과시간에 따른 엽록소 함량의 변화가 적었으며, 물 흡수력이 높았다. 또한 처리 후 일정기간 엽록소 함량이 증가하였으며, 다른 Hosta, 속 품종에 비해 수명이 길어 화훼장 식용 절엽으로 개발이 가능한 품종으로 선발되었다.

• 한국의학물리학회지:의학물리
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• 제30권2호
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• pp.59-63
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• 2019

Purpose: To manage radiation measurement equipment, a web-based management program has been developed in this study. Materials and Methods: This program is based on a web service and Java Server Pages (JSP) and employs compatibility and accessibility. Results: The first step in the workflow has been designed to create accounts for each user or organization and to log in. The program consists of two parts: fields for listed instruments, and measurement information. The instruments for measuring radiation listed in this program are as follows: ionization chambers, survey meters, thermometers, barometers, electrometers, and phantoms. Instrument properties can be put in the recording fields and browsing for associated instruments can be performed. The main part of the program is the cross-calibration for each ion chamber. For instance, the ionization chamber to be used as a relative dosimeter can be registered by cross-calibration data with a reference chamber calibrated by an accredited laboratory. This program supports methods using the central axis transfer theory for cross-calibration for the ionization chambers. The reference and field ionization chambers were placed in a solid water phantom along the beam central axis at two different depths, and then the positions were switched. Each measured value was used for calculating the cross-calibration factor. Conclusions: Because many instruments are used and managed in radiation oncology departments, systematic, traceable recording is very important. The web-based program developed in this study is expected to be used effectively in the maintenance of radiation measurement instruments.

• 환경생물
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• 제38권1호
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• pp.61-70
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• 2020

A eukaryotic microalga was isolated from seawater in Janghang Harbor, Korea and its morphological, molecular, and physiological characteristics were investigated. Due to its simple morphology, no distinctive characters were found by morphological observation, such as light microscope or scanning/transmission electron microscopy (S/TEM). However, molecular phylogenetic evidence inferred from the concatenated small subunit (SSU) 18S rRNA and internal transcribed spacer (ITS) sequence data indicated that the isolate belonged to the newly described Micractinium singularis. Furthermore, it was clustered with Antarctic Micractinium strains and it also showed a psychrotolerant property, surviving at temperatures as low as 5℃. However, its optimal growth temperatures range from 15℃ to 25℃, indicating that this microalga is a mesophile. Additionally, gas chromatography-mass spectrometry (GC/MS) analysis showed that the isolate was rich in nutritionally important omega-3 polyunsaturated fatty acid, and high-performance liquid chromatography analysis (HPLC) revealed that the high-value antioxidant lutein was biosynthesized as an accessory pigment by this microalga, with glucose as the major monosaccharide. Therefore, in this study, a Korean marine M. singularis species was discovered, characterized, and described. It was subsequently added to the national culture collections.

• 환경생물
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• 제37권4호
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• pp.526-534
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• 2019

Chlorella gloriosa (Chlorellaceae, Trebouxiophyceae) was isolated from seawater off the coast of the Dokdo Islands in Korea. An axenic culture was established using the streak-plate method on f/2 agar media supplemented with antibiotics, allowing identification of the isolate by morphological, molecular, and physiological analyses. The morphological characteristics observed by light and electron microscopy revealed typical morphologies of C. gloriosa species. The molecular phylogenetic inference drawn from the small-subunit 18S rRNA sequence verified that the microalgal strain belongs to C. gloriosa. Additionally, gas chromatography-mass spectrometry analysis showed that the isolate was rich in nutritionally important omega-3 and -6 polyunsaturated fatty acids and high-performance liquid chromatography analysis revealed that the high-value antioxidants lutein and violaxanthin were biosynthesized as accessory pigments by this microalga, with arabinose, galactose, and glucose as the major monosaccharides. Therefore, in this study, a Korean marine C. gloriosa species was discovered, characterized, and described, and subsequently added to the national culture collection.

• 복식
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• 제63권5호
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• pp.132-150
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• 2013

The purpose of this study is to examine misnomers about King Heungdeok's "Prohibition of Clothing" by comparing the writings of Jeongdukbon [正德本] and Juzabon [鑄字本], which were different versions of the original texts of "Samguksagi [三國史記]", with 11 related books written between 1948 and 2012. In addition, this study is reconsidered the terms about several clothes as well as the values of fabrics. The study has come up with the following conclusions. 1. We suggested the correction about a misnomer in the 11 books and the misnomers for fabric items appeared most frequently. The records of Jeongdukbon about some of the items were different from ones of Juzabon, especially regarding noble woman's sash were written according to the record of Juzabon in most of the related books. However, when the commonplace woman's sash was taken into consideration, we could suppose that the record of Jeongdukbon was more reliable. 2. We examined the terms for Yodae [腰帶] and Yoban. It can be inferred from the original texts that the Yodae were different in material and function compared to the Dae [帶]. In other words, the wearing position of male's metal Yodae was the waist, whereas the females wore their Dae made of fabrics on their chest. An example of this can be seen from the female clay images of Tomb Yonggang-dong [龍江洞]. Moreover, female's Yo and Ban were distinct items on the basis of documents. For this reason, we suggested that Yodae and Yoban should be separated and written in books. 3. We suggested that Ju [紬, silk tabby] might be valuable according to an result of analysis about the value of recorded fabrics. Besides, Po [布, hempcloth] presumably were used as higher quality fabric than Myeonju [綿紬, silk tabby] on some items because Po was graded on the density by each class.