• Environmental Analysis Health and Toxicology
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• 제13권1_2호
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• pp.43-53
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• 1998

Ambient air levels of polycyclic aromatic hydrocarbons(PAHs) are of concern because of their potential for adverse health effects including transformation of some of these substances to mutagens and carcinogens by mammalian microsomal enzyme system. Airbone particulate samples were collected by a conventional high-volume sampler and by an Anderson cascade impactor on 2 to 3 days in each month over a period of 1 year at a representative site of the heavy traffic area of Seoul from beptember 1994 to August 1995. Ten individual PAHs in sizable air particulates of each stage of two months were separated and analyzed by gas chromatography/mass spectrometry. As a results of analysis, the gross concentrations of PAHs in the fine and coarse particles were higher in the winter month than in the spring, followed in descending order by in the fall and summer. In a study of dependency of 10 PAHs compounds on size distribution of particles at heavy traffic area found that about 85% of the total PAHs content was associated with particles less than 2.0um (fine particles) in diameter of winter sampling period. while 79% were associated with this size fraction during summer period. In according to the mean concentrations of the 10 PAHs in 7 size classification from < 0.38 to> 10.1, the 'size was the smaller, PAHs concentration was the higher. Thus it was found that PAHs concentration was greatly affected by air particle size. Annual mean benzo(a)pyrene equivalents was 5.88ng/m$^3$ and obtained by applying, toxic equivalency factor developed by Nisbet and Lagoy.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제34권2호
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• pp.140-147
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• 2012

Microvascular reconstruction, in the oral and maxillofacial regions, is a widely accepted as the best way to overcome the complex oral cavity defects. Many patients requiring composite reconstructions have been treated previously with radiation therapy, chemotherapy, selective and/or functional neck dissection or any of these combinations. In many cases of these patients, inadequate neck vessels for the microanastomosis of free flap are available, due to a lack of recipient vessels in the neck, poor vessel quality or vessel caliber mismatch. To achieve a tension-free anastomosis, vein grafting must be considered to span the vessel gap between the free flap pedicle and the recipient neck vessels. Although most microsurgeons believed that interpositional grafts are to be avoided due to vessel thrombosis and increased number of necessary microanastomosis, we, authors have some confidence of equivalency between reconstruction with and without interpositional saphenous vein graft. The great saphenous vein, also known as the long saphenous vein, is the large subcutaneous superficial vein of the leg and thigh. It joins with the femoral vein in the region of femoral triangle at the saphenofemoral junction, and coursed medially to lie on the anterior surface of the thigh before entering an opening in the fascia lata, called the saphenous opening. For a better understanding of the great saphenous vein graft for the interpositional vessel graft in the oral cavity reconstructions, and an avoidance of any uneventful complications during these procedures, the related surgical anatomies with their harvesting tips are summarized in this review article in the Korean language.

• Journal of Oral Medicine and Pain
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• 제43권2호
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• pp.34-40
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• 2018

Purpose: The aim of this study was to translate the original English version of tampa scale for kinesiophobia for temporomandibular disorders (TSK-TMDs) for cultural equivalency into Korean language and to evaluate the reliability of the Korean version of the TSK-TMD among symptom free subjects. Methods: The original version of TSK-TMD was translated and cross-culturally adapted following international guidelines. A total 90 subjects (50 women, 40 men) were participated to fill out the questionnaire. The internal consistency and test-retest reliability with a one- or two-week time interval were evaluated. Results: The internal consistency of TSK-TMD of the original and the modified 12-item TSK-TMD were 0.866, and 0.858, respectively using the Cronbach's alpha coefficient. And the internal consistency of activity avoidance (AA) and somatic focus (SF) subscale were 0.838 and 0.807 assessed with Cronbach's alpha indicating excellent reliability. Test-retest reliability of the original TSK-TMD measured by the intra-class correlation coefficient (ICC) was 0.764, and coefficients value of the 12-question TSK-TMD was 0.752. Test-retest reliability of AA subscale was 0.722 and SF subscale was 0.677 measured by ICC. Conclusions: The Korean version of the TSK-TMD questionnaire was found to be a reliable instrument and successfully translated to Korean language. There are no significant differences between overall and modified version of TSK-TMD. It can be used as a valuable instrument for the analyses of the psychosocial aspects of the TMD patients in Korea.

• Child Health Nursing Research
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• 제18권2호
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• pp.53-59
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• 2012

Purpose: This study was done to verify the reliability and validity of the Korean version of DMCI in Korean adolescents. Methods: A methodological study design was used with Cronbach's ${\alpha}$ for reliability, and an exploratory factor analysis and contrasted groups approach for construct validity. DMCI was translated into Korean and tested with a sample of 406 adolescents in Korea. The data were analyzed using Cronbach's ${\alpha}$, item correlation with total, principal component factor analysis, and t-test. Results: The translated content of the DMCI was validated by nursing faculty members and translation equivalency was obtained. The Cronbach's ${\alpha}$ of the DMCI simplified with 18 items was .78. The factor analysis revealed three factors explaining 41.5% of total variance and the corresponding factors were self-observation (21.6%), self-judgement (11.4%), and self-confidence (8.6%). The mean score for the DMCI in the aggression group was significantly lower than the non-aggression group. Conclusion: Results of this study suggest that the Korean version of DMCI can used as a reliable and valid measure to assess decision making competency in Korean adolescents.

• 항공우주시스템공학회지
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• 제16권3호
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• pp.35-41
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• 2022

UAM(Urban Air Mobility) 은 승객과 화물을 운반할 수 있는 새로운 형태의 안전하고 적합한 운송수단으로써 각광받고 있다. UAM 의 상업적인 사용은 2025년부터 시작될 것으로 예측되고 있다. UAM의 생산률은 기존 항공기 생산률보다 자동차 생산률에 더 가까울 것으로 예측되므로, 대량 생산 항공기에 대비한 새로운 인증 방안을 구축할 필요가 있다. 이러한 UAM은 구조물의 중량을 줄이기 위해 복합재료가 주 재료로써 사용될 것으로 예상되고 있다. 따라서 본 연구에서는 항공기용 복합재료 시범인증을 수행함으로써 국내 복합재료 인증 방안을 제시하고 인증소재를 소형 항공기용 부품에 적용하기 위한 연구를 수행하였다. 본 연구를 통해 대량생산이 필요한 UAM 항공기의 인증 시간을 절감할 수 있을 것으로 예상한다.

• 한국축산식품학회지
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• 제44권3호
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• pp.662-683
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• 2024

Thai-Native×Anglo-Nubian goat meat cooked by grilling (GR), sous vide (SV), and microwave (MW), was compared to fresh meat (Raw) in terms of flavor development. Non-volatile [i.e., free amino acids, nucleotide-related compounds, taste active values (TAVs) and umami equivalency, sugars, lipid oxidation, Maillard reaction products] and volatile compounds, were investigated. Notably, inosine monophosphate and Glu/Gln were the major compounds contributing to umami taste, as indicated by the highest TAVs in all samples. Raw had higher TAVs than cooked ones, indicating that heat-cooking removes these desirable flavor and taste compounds. This could be proportionally associated with the increase in aldehyde, ketone, and nitrogen-containing volatiles in all cooked samples. GR showed the highest thiobarbituric acid reactive substances (1.46 mg malonaldehyde/kg sample) and browning intensity (0.73), indicating the greatest lipid oxidation and Maillard reaction due to the higher temperature among all cooked samples (p<0.05). In contrast, SV and Raw exhibited similar profiles, indicating that low cooking temperatures preserved natural goat meat flavor, particularly the goaty odor. The principal component analysis biplot linked volatiles and non-volatiles dominant for each cooked sample to their unique flavor and taste. Therefore, these findings shed light on cooking method selection based on desirable flavor and preferences.

• 비파괴검사학회지
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• 제30권4호
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• pp.386-395
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• 2010

국내 원자력 증기발생기 관리프로그램 통합지침서는 와전류검사 장비 및 기법에 대한 자격인정 절차를 규정하고 있다. 이러한 자격인정 절차에는 두 가지 방법이 있다. 첫 번째는 열교환기에서 인출된 튜브 혹은 인공결함에 의한 결함 발생기구 및 기법을 사용하여 장비 혹은 탐촉자를 인정한다. 두 번째는 이미 인정된 장비 혹은 탐촉자 특성과 동등함을 입증할 경우, 즉 검사기술사양서에 기술된 필수변수 범위가 만족된다면 인정절차 없이 이미 인정된 장비 혹은 탐촉자를 대체하여 사용할 수 있다. 본 논문은 국산화 개발된 보빈탐촉자와 이미 해외에서 인정된 보빈탐촉자의 특성을 비교 수행한 결과를 수록하였다. 탐촉자의 전기적 특성평가를 위해 임피던스 및 공진주파수를 측정하였으며, 자기장 특성평가를 위해 유효주사 자기장 폭 측정, 충전율 계수 측정, 깊이계수 측정, 축방향 길이계수 측정, 횡방향 폭계수 측정, 위상각 대 깊이곡선 측정 및 직류포화세기를 측정하였다. 본 특성시험 결과 두 종류의 탐촉자 특성이 거의 동등한 것으로 평가됨에 따라 향후 현장 적용을 위한 기반을 구축한 것으로 판단된다.

• 전산구조공학
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• 제8권3호
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• pp.103-111
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• 1995

지진하중과 같은 동적인 하중에 대한 다자유도 구조물의 비선형 해석은 많은 양의 계산을 요구한다. 이런 계산상의 어려움을 감소시키기 위하여 다자유도를 가진 복잡한 구조물의 비선형해석을 간략화된 동위 구조물 (Equivalent Nonlinear System(ENS))을 이용해 구할 수 있는 약산법을 제시한다. 간단한 동위 구조물은 원구조물의 가장 중요한 구조물의 성질을 가지고 있는데 구조물의 처음 두 개의 주기(natural periods)의 동적 특성 및 전체 항복변위(global yield displacement)를 가진다. 구조체 반응으로 이 논문에서는 구조체의 전체변위 및 층간변위가 고려된다. 구조체의 전체 변위 및 층간변위를 얻기 위하여 전체 반응수정계수(global response scaling factor) R/sub G/와 국부반응수정계수(local response scaling factor)R/sub L/을 동위 구조물로부터 얻어진 변위에 적용한다. 이 반응수정계수는 다자유도 구조물의 비선형 해석을 통하여 얻어진 변위들과 동위 구조물을 이용해 얻어진 변위들을 이용해 광범위한 회기분석을 통하여 구조물의 연성과 첫번째 두 모드의 질량참여계수의 함수형태로 얻는다. 반응수정계수를 가진 동위 구조물을 만들기 위하여 철골 모멘트 연성 골조 방식의 구조물(Special Moment Resisting Steel Frames (SMRSF))을 이 논문에서는 고려한다. 함수형태로 표현된 반응수정계수는 동위 구조물의 반응에 적용되어 복잡한 구조물의 비선형 반응을 얻을 수 있다.

• Environmental Analysis Health and Toxicology
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• 제21권1호
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• pp.45-56
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• 2006

This study was conducted to investigate seasonal distributions of fine particles ($PM_{2.5}$) and associated polycyclic aromatic hydrocarbons (PAHs) at three cities. $PM_{2.5}$ samples were collected on glass fiber filters at urban (Chuncheon), metropolitan (Seoul), and industrial complex sites (Ulsan) from September, 2002 to February, 2004 using the Andersen FH 95 Particulate Sampler. About five 24-hour samples were collected from each site per season. The filters were analyzed for mass and six selected PAHs concentrations. $PM_{2.5}$ concentrations were the highest either in winter or spring, which could be attributed to the increase of fossil fuel combustion in winter or the transport of yellow sand to the Korean peninsula from China in spring, respectively. Regional $PM_{2.5}$ concentrations were higher in the order of Seoul>Chuncheon>Ulsan without statistical difference among cities. The filters were extracted using dichloromethane in an ultrasonicator and analyzed for six PAHs (anthracene, fluoranthene, pyrene, benzo[a]anthracene, chrysene, and benzo[a]pyrene) with HPLC. Total PAHs concentrations were statistically different among seasons in each site, and the highest concentrations were observed in winter at each sampling site. For total samples collected, the median total PAHs concentrations in Chuncheon ($4.6ng/m^3$) and Seoul ($4.4ng/m^3$) were approximately two times higher than that in Ulsan ($2.1ng/m^3$). Chrysene was a component found in the highest proportion among total PAHs at each site. Carcinogenic risks calculated based on the BaP toxic equivalency factors (TEFs) over the whole sampling period were higher in the order of Chuncheon>Seoul>Ulsan. This study suggests that the atmosphere of Chuncheon is contaminated with particulate matter and PAHs at the levels equivalent to those of Seoul and that an appropriate measure needs to be taken to mitigate human health risks from inhalation exposure to airborne fine particles.

• 한국항해항만학회지
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• 제45권3호
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• pp.130-137
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• 2021

본 연구의 목적은 울산 부유식 해상풍력발전단지를 대상으로 서식지 등가성 분석법(Habitat Equivalency Analysis : HEA)을 적용한 가치평가를 통해 해당 해양공간 특성평가를 위한 객관적인 평가기준 제시에 있다. 울산 부유식 해상풍력발전단지 설립으로 인해 사용이 금지된 해역(5,017.6ha)에서는 상업적 피해, 생태계 파괴 등 여러 피해가 발생한다. 피해의 경제적 가치 규모 산정을 위한 대체 복원사업을 인공어초사업으로 선정하고 이를 HEA로 추정하였다. 추정 결과, 사회적 할인율 4.5%, 4년째부터 성숙도 100%를 기본 가정으로 한 경우 피해액은 약 457억원으로 나타났다. 본 연구에 사용된 HEA는 객관적이고 명확한 DATA를 기본으로 가치를 산정하기 때문에 해양공간 특성평가 시 발생할 수 있는 불합리성을 해결할 수 있을 것이다. 따라서, 본 연구의 결과는 향후, 해양공간계획의 시행에서 발생 가능한 이해관계자들 간의 갈등 해소에 도움이 될 것이다.