• 한국전산구조공학회논문집
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• 제25권4호
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• pp.331-338
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• 2012

현재 국내에서 EM-120에 의해 검측된 틀림 데이터는 매우 불규칙적인 형태를 나타내며 데이터 분석 시 다양한 문제점을 가지고 있다. 본 연구에서는 궤도의 효율적인 유지관리를 위해 검측된 틀림데이터의 특징과 문제점을 분석하고, 이를 보완할 수 있는 효율적인 처리 기법을 개발하였으며, 정제된 데이터의 ARIMA 분석을 통해 검측데이터와 계절 변화의 상관관계 분석을 수행하였다. 또한 회귀모형, 지수평활법, ARIMA 모형 등 다양한 예측 모델의 적용을 통해 검측 데이터의 시계열 분석을 수행하고, 궤도 틀림 데이터의 예측 모델에 적합한 최적 모델 선정과 관련한 연구를 수행하였다.

• Smart Structures and Systems
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• 제25권3호
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• pp.369-384
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• 2020

A wavefield sparse reconstruction technique based on compressed sensing is developed in this work to dramatically reduce the number of measurements. Firstly, a severely underdetermined representation of guided wavefield at a snapshot is established in the spatial domain. Secondly, an optimal compressed sensing model of guided wavefield sparse reconstruction is established based on l₁-norm penalty, where a suite of discrete cosine functions is selected as the dictionary to promote the sparsity. The regular, random and jittered undersampling schemes are compared and selected as the undersampling matrix of compressed sensing. Thirdly, a gradient projection method is employed to solve the compressed sensing model of wavefield sparse reconstruction from highly incomplete measurements. Finally, experiments with different excitation frequencies are conducted on an aluminum plate to verify the effectiveness of the proposed sparse reconstruction method, where a scanning laser Doppler vibrometer as the true benchmark is used to measure the original wavefield in a given inspection region. Experiments demonstrate that the missing wavefield data can be accurately reconstructed from less than 12% of the original measurements; The reconstruction accuracy of the jittered undersampling scheme is slightly higher than that of the random undersampling scheme in high probability, but the regular undersampling scheme fails to reconstruct the wavefield image; A quantified mapping relationship between the sparsity ratio and the recovery error over a special interval is established with respect to statistical modeling and analysis.

• 대한약침학회지
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• 제25권4호
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• pp.382-389
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• 2022

Objectives: The Korean Industrial Standard (KS) for sterile acupuncture needles was established in 2009 based on research on the quality control of acupuncture needles. We aimed to determine the quality of acupuncture needles available in South Korea in 2021 by examining their surface condition and chemical composition using field-emission scanning electron microscopy (FE-SEM) and energy-dispersive X-ray spectroscopy (EDS). Methods: In South Korea, there are 23 brands of acupuncture needles, and we examined 10-15 needles from each brand, resulting in a total of 285 needles. The microstructures of the needles were assessed by SEM. Using SEM images, we evaluated the acupuncture needle tips for the following defects/aspects: scratches, lumps, detached coating, bent tip, and tip sharpness. EDS was used to determine the chemical composition of the selected acupuncture needles. Results: Overall, 88.4% of 285 needles were found to have at least one type of abnormality. The most frequently observed abnormalities were scratches and dents on the surface (68.1%), followed by detached coating (63.2%), and lumps (61.8%); blunt tips were observed in about 24% of them. Of 252 needles with at least one defect, 86.9% had two or more types of defects. The ratio of the number of needles with any defect to that of needles without any defect varied among brands, ranging from 50% to 100%. Regarding foreign materials, higher proportions of Si and O were observed on the needles, indicating incomplete or detached silicone coating. Conclusion: The quality of acupuncture needles varied among brands, suggesting that further improvements can be made through various inspection methods.

• 한국식품영양학회지
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• 제21권4호
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• pp.562-571
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• 2008

The principal objective of this study was to assess dietitian's awareness and performance with regard to food suppliers' selection guidelines and purchase guidelines for the receipt of safe food materials. A questionnaire was administered to 203 dietitians working at an elementary school in Gyeonggi North province, and 190 responses were ultimately returned. Excluding responses with incomplete answers and significant missing data, 161 responses(79.3%) were ultimately utilized for data analysis. We determined that meat/poulty and seafood were purchased mainly by manufacturer's branch(59.8% and 78.3%), and processed food and kimchi were generally purchased by producer's cooperatives(47.7% and 44.9%). 78.3% of the contracts were made via informal purchasing and the frequency of contracts was less than 3 times per year(53.4%). Market studies were conducted individually(54.7%), and by group(47.2%). Dietitian and parents volunteered(50.3%) or dietitians, and school and foodservice staffs(45.3%) participated - together in receiving and inspection. School contracted with $4{\sim}5$(39.1%) and $6{\sim}8$ food suppliers(29.8%). Dietitians(42.3%) or school councils(40.2%) evaluated food suppliers once per semester(60.2%). The majority of dietitians(96.3%) conducted sanitary education for food suppliers once per semester (68.3%). All 13 guidelines which were usually used to evaluate food suppliers were thought to be important(more than 4) based on a 5 scale(1: never important, 5: very important). Among them, 'sanitary storage status of food products(4.85)', 'have a chill car(4.83)' and 'proper control of refrigerator, freezer and storage room(4.81)' were the most crucial guidelines. As dietitians evaluated food supplier's-observances of 13 guidelines, 'have a chill car(4.89)', 'hold medical examination of employees(4.89)' and 'hold liability insurance for handling product(4.80)' were fulfilled relatively well. The guidelines for conducting education for their employees(4.45) and keeping their establishment and equipment sanitary(4.79) were important, but were not observed well(3.39 and 3.37). Additionally, the difference between the importance and the observance score of the 'HACCP certificate' were fairly significant(4.44 and 3.54). Dietitians tended to report that purchasing management related to the removal of foodborne illness factors(4.71), return confirmation(4.50) and purchase specification(4.32) were important. The difference between importance and performance was highest in the process of changing food suppliers when the contracts were violated more than three times. Dietitian's age, education work experience and employment type had no observable effects on how important they considered purchase management to be, but their work experience significantly affected performance in terms of the removal of foodborne illness factors(p<0.05). As supplier management is the most critical factor, it is clearly desirable to educate suppliers at specialized training centers and to supervise suppliers in accordance with the established sanitary guidelines.

• Journal of the Korean Wood Science and Technology
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• 제44권5호
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• pp.617-621
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• 2016

본 연구는 규제해충(이하 해충이라 칭함) 검출 건수 상위 3개국인 말레이시아, 인도네시아, 중국의 집성재 생산업체에 대한 현장실사를 통해 해충 검출 원인을 파악하여 검역 안전성 확보를 위한 적정 집성재 생산공정을 제시하고자 수행되었다. 현장실사 결과, 수입 집성재로부터 해충 검출은 생산공정상의 문제(층재의 천연건조 또는 미흡한 열기건조, 건조 층재의 부적절한 보관, 집성재의 불완전 포장)로 확인되었다. 특히 중국은 오동나무 층재를 전적으로 천연건조하는 점을 비롯하여 생산공정이 전반적으로 가장 불량하였다. 향후 수입 집성재의 검역 안전성을 확보하기 위해서는 수입업체 스스로 해외 생산업체에 층재에 기 서식하던 해충의 구제가 가능하면서 동시에 건조 층재나 완제품인 집성재에 대한 해충 가해를 예방할 수 있는 타당한 집성재 생산공정(층재의 적절한 열기건조, 집성접착 전까지 건조 층재의 밀봉 보관, 집성재의 밀봉 포장)의 적용을 요구하여 수입 집성재로부터 해충이 검출되지 않도록 해야 할 것이다.

• 대한유전성대사질환학회지
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• 제17권3호
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• pp.77-84
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• 2017

Purpose: From the early 1990's, use of Tandem mass spectrometry in neonatal screening test, made early stage detection of disorders that was not detectable by the previous methods of inspection. This research aims to evaluate the frequency of positive results in national neonatal screening test by Tandem mass spectrometry and its usefulness. Methods: A designated organization for inherited metabolic disorder executed neonatal screening test on newborns using Tandem mass spectrometry from January 2006 to December 2015, followed by the investigation of these data by the Planned Population Federation of Korea (PPFK), and this research analyzed those inspected data from the PPFK. Results: Among total childbirth of 4,590,606, from January 2006 to December 2015, 3,445,238 were selected for MS/MS and conduction rate was 75.1%. 261 out of the selected 3,445,238 were confirmed patients and for last decade, detection rate of total metabolic disorder was 1/13,205. In 261 confirmed patients, 120 had an amino acid metabolic disorder and its detection rate was 1/28,710 and 110 had an organic acid metabolic disorder and detection rate was 1/31,320. Also, 31 had a fatty acid metabolic disorder and detection rate was 1/13,205. Conclusion: Inherited metabolic disorder is very rare. Until now, it was difficult to precisely grasp an understanding on the national incidence of inherited metabolic disorder, due to lack of overall data and inconsistent and incomplete long-term result analysis. However, this research attempted to comprehensively approach the domestic incidence, by analyzing previous 10 years of data.

• 한국응용곤충학회지
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• 제46권2호
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• pp.175-182
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• 2007

국내 서식하는 복숭아순나방 (Grapholita molesta (Busck))과 복숭아심식나방 (Carposina sasakii (Matsumura))의 유충은 사과 과실내부를 섭식하여 피해를 주는 해충이다. 사과를 수출할 때 복숭아심식나방은 수출대상국들로부터 검역 대상해충이다. 반면에 복숭아순나방은 광범위한 분포로 비교적 수입국으로부터 검역 대상 해충은 아니지만, 사과 과실 내부에서 발견되는 경우 복숭아심식나방으로 오인될 수 있다. 이는 발견되는 유충을 가지고 형태적으로 두 종을 구분하기 어렵기 때문이다. 특별히 수입국 검역단계에서 이러한 불완전한 동정 실태는 수출 사과의 폐기 또는 반송과 수출중단 등과 같은 막대한 경제적 손실을 초래하게 된다. 이에 이들을 구분할 수 있는 분자지표 개발이 요구되었다. 두 종의 미토콘드리아 DNA를 대상으로 다형을 보이는 여러 영역의 염기서열을 분석하였다. 이 서열을 바탕으로 진단용 제한위치가 결정되고 종 특이적 프라이머가 제작되었다. 본 연구는 세 부위의 종 특이적 제한효소 위치에 따라 PCR-RFLP 기술과 종 특이적 프라이머를 이용하여 진단용 PCR 기술을 개발하였다.

• 한국폐기물자원순환학회지
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• 제35권7호
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• pp.616-626
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• 2018

The quality standards of solid refuse fuel (SRF) define the values for 12 physico-chemical properties, including moisture, lower heating value, and metal compounds, according to Article 20 of the Enforcement Rules of the Act on Resource Saving and Recycling Promotion. These parameters are evaluated via various SRF Quality Test Methods, but problems related to the heavy metal content have been observed in the microwave acid digestion method. Therefore, these methods and their applicability need improvement. In this study, the appropriate testing conditions were derived by varying the parameters of microwave acid digestion, such as microwave power and pre-treatment time. The pre-treatment of SRF as a function of the microwave power revealed an incomplete decomposition of the sample at 600 W, and the heavy metal content analysis was difficult to perform under 9 mL of nitric acid and 3 mL of hydrochloric acid. The experiments with the reference materials under nitric acid at 600 W lasted 30 minutes, and 1,000 W for 20 or 30 minutes were considered optimal conditions. The results confirmed that a mixture of SRF and an acid would take about 20 minutes to reach $180^{\circ}C$, requiring at least 30 minutes of pre-treatment. The accuracy was within 30% of the standard deviation, with a precision of 70 ~ 130% of the heavy metal recovery rate. By applying these conditions to SRF, the results for each condition were not significantly different and the heavy metal standards for As, Pb, Cd, and Cr were satisfied.

• 지능정보연구
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• 제21권1호
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• pp.99-118
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• 2015

정보 시스템 개발에 있어 객체지향 프로그래밍 언어가 널리 사용된다. 이와 함께 객체지향 설계를 뒷받침하는 개념적 모델링 언어에 관한 관심도 높다. 이를 배경으로 통합 모델링 언어 혹은 UML로 알려진 개념적 모델링 언어는 여러 객체 지향 프로그래밍 언어와 함께 사용되면서 사후적 표준으로 자리 잡았다. UML은 클래스를 설계의 중심에 둔다. 또한 클래스들 간의 관계를 통해 체계적인 이해를 가능하게 한다. 특히 부분에 해당하는 클래스들과 전체에 해당하는 클래스의 관계인 부분-전체 관계를 설계할 수 있는 문법 또한 UML에 포함된다. 현실 세계에 부분-전체 관계로 파악될 수 있는 여러대상들이 존재하고 비즈니스 활동에 존재하는 각종 역할들의 구조에서도 부분-전체 관계로 표현될 수 있는 대상들이 보편적으로 보인다. 따라서 UML로 클래스들 간의 부분-전체 관계를 드러내는 일은 자연스럽다. 문제는 부분-전체 관계를 파악하는 활동은 UML 2.0의 표준에 포함되었으나 실제 설계 과정에서 적극 활용하기 위한 실천적 이론화가 부족하다는 점이다. 부분-전체 관계를 집합연관과 복합연관으로 세분화한 UML 문법은 표현 양식에서 부족함은 없을지라도 어떤 대상을 부분-전체로 파악하고, 이를 어떻게 집합연관이나 복합연관으로 분류해야 할 것인지에 대한 판단이 쉽게 결여된다. 지금까지 UML의 부분-전체 관계 규명은 언어적 표현법을 활용하는 것에 치우쳤다. 이와 같은 문제에 대한 대안을 제시하기 위해 본 연구는 메타모델 형식화 이론을 기반으로 UML 사용자가 부분-전체 관계를 판단하고 이를 집합연관과 복합연관으로 분류할 수 있는 실천적 대안을 제시한다. 이를 활용한 실험의 결과 메타모델 형식화가 UML 사용자들에게 통용되어 온 언어적 구분법보다 더 나은 결과를 낳는다는 점이 밝혀졌다. 본 연구는 부분-전체의 판별과 구분에 도움을 주는 실용적인 방법을 제안하고 검증하였다는 점에서 의의가 있다.