• Structural Monitoring and Maintenance
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• 제5권2호
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• pp.205-229
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• 2018

Energy induced by minor earthquake and micro vibration cannot be dissipated by traditional buckling-restrained braces (BRBs). To solve this problem, a new type of hybrid passive control device, named as VE-BRB, which is configured by a BRB with high-damping viscoelastic (VE) layers, is developed and studied. Theoretical analysis, performance tests, numerical simulation and case analysis are conducted to study the seismic behavior of VE-BRBs. The results indicate that the combination of hysteretic and damping devices lead to a multi-phased nature and good performance. VE-BRB's working state can be divided into three phases: before yielding of the steel core, VE layers provide sufficient damping ratio to mitigate minor vibrations; after yielding of the steel core, the steel's hysteretic deformations provide supplemental dissipative capacity for structures; after rupture of the steel core, VE layers are still able to work normally and provide multiple security assurance for structures. The simulation results agreed well with the experimental results, validating the finite element analysis method, constitutive models and the identified parameters. The comparison of the time history analysis on a 6-story frame with VE-BRBs and BRBs verified the advantages of VE-BRB for seismic protection of structures compared with traditional BRB. In general, VE-BRB had the potential to provide better control effect on structural displacement and shear in all stages than BRB as expected.

• 자원환경지질
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• 제1권1호
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• pp.35-46
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• 1968

Some of geologists in Korea recently postlated that Okchon system previously known to be precambrian age was the metamorphosed sediments of post-Chosen (Ordovician and pre-Kyeongsang (late Jurassic to Cretaceous) periods, or even definitely of Triassic period simply on the basis of the fact that Okcheon system overlies the Great Limestone series of Chosen system of Camber-ordovician age, and of other few assumptions of minor importance. As a result of such correlation, thick series of metasediments and Okcheon system of unknown age were established in this particular region and vaguely correlated to Paleozoic and Mesozoic sediments. Recent study done by the author reveled that: 1) only the upper Okcheon bed of S. Nakamura was true Okcheon system, and the middle and lower Okcheon beds were excluded, because they were correlated to Cambrian and Permian sediments resfectively, 2) Sangnaeri, Seochangri, and rengam formations of unknown age, and Baekhwasan, Jobong, and Ihwaryeong formations of Okcheon system of also unknown age were the metamorphosed Yangdeok system of Cambrian age, all of these formations were differentiated by the previous workers and were equivalent to the middle Okcheon system of S. Nakamure, and. 3) These metamorphosed Yangdeok system overlaid apparently the Great Limestone series in forms of overthrust and klippe which were produced by the orogeny took place during post-Daedong and pre-Kyeongsang period (probably middle to the Jurassic). The Sobaeksan Range, folded mountain Chains was also formed by this orogeny. Thus, Okcheon system newly defined by the author is precambrain age and consists in ascending order of Kemyenogsan, Hyangsan dolomite, and Daehangsan quartzite formation which were previously classified into metasediments of unknown age, and Munjuri, and Hwangkanri, formations which were differentiated into Okcheon system unknown age by the previous workers, but are of reversed sequence. Myeongori and Bukrori formations of Okcheon System are regard by the author as part of Hwangkanri formation. Few other assumption of minor important taken by the previous workers as their positive evidences are carefully explained that they were misinterpreted.

• Animal Systematics, Evolution and Diversity
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• 제8권1호
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• pp.35-56
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• 1992

한국 담수산 윤충류의 분류학적 연구를 위하여 1990년 3月부터 1992년 2월까지 전국 일대에 산재해 있는 댐, 호수, 저수지, 연못, 논, 웅덩이 등을 대상으로 총 205개 지점에서 채집을 실시하여 조사한바, Brachionidae과의 Brachionus속에 9아종 2변종 6형이, 그리고 Platyas속에는 1종이 밝혀졌는데, 그중 Brachionus속의 1아종 4형 : Brachionus urceolaris bennini, B. angularis f. bidens, B. quadridentatus f. rhenanus, B. forficuIa f. minor, B. forficula f. angularis가 한국 미기록으로 판명되어 기재와 함께 도판을 작성하였고, 본 연구에서 확인된 Brachionus와 Platyas속내의 종들에 대해서는 물론, 연차적인 발표를 목적으로 한국산 윤형동물에 대한 전체척언 검색표를 만들었다. 따라서 지금까지 기록된 한국산 윤충류는 총 2강 4목 14과 40속 134종, 15아종, 9변종, 9형이 된다.

• 한국전문물리치료학회지
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• 제17권2호
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• pp.25-32
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• 2010

The purpose of this study was to investigate the most effective and comprehensible method for the assessment of resting scapular position (RSP) and pain level (PL) in unilateral shoulder pain (USP). Fifty volunteers with USP were involved in the study. Resting scapular assessments of the patients' pain sides (PS) and non-pain sides (NPS) were evaluated. The assessment tools for RSP are: 1) sternal notch (SN) to coracoid process (CP) distance 2) 3rd thoracic spinous process (T3S) to posterolateral angle of acromion (PLA) distance 3) scapular index 4) 8th thoracic spinous process (T8S) to inferior angle of scapular (IAS) distance 5) supine measurement of pectoralis minor (PM) distance 6) standing PM distance 7) PM index (PMI) and 8) PM pain. The paired t-test was used to compare PS and NPS in RSP. Pearson correlation analysis was used to confer a relationship between the PL and RSP. The results of this study indicated that: 1) all the variables between the PS and NPS for RSP were statistically significant(p<.05) and 2) the PMI showed the strongest relationship in the correlation analysis between RSP and PL(p<.05, r=.37). Therefore, it can be concluded that there is a relationship between PMI and PL and it is suggested that an assessment tool using PMI to diagnose shoulder pain would be clinically effective.

• 한국산학기술학회논문지
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• 제16권9호
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• pp.6391-6396
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• 2015

2차원 응력조건에 대한 von Mises 항복기준의 특징을 살펴보기 위해 탄성변형률이 0이 되는 평면변형률 조건과 소성변형률증분이 0이 되는 평면변형률 조건을 고려해 보았다. 탄성변형률이 0인 평면변형률조건을 통해 얻은 항복함수와 평면응력조건에서의 항복함수는 기하학적으로 타원을 나타내는데 두 경우에 대한 기하하적 비교를 타원의 장, 단축의 길이비와 이심률의 비로 나타낼 때 단축비는 같았으나 장축비 및 이심률의 비는 포아송비의 함수로 표현되었다. 탄성변형률이 0인 평면변형률조건을 통해 얻은 von Mises 항복기준에 대하여 탄성거동을 보이는 영역은 포아송비가 커짐에 따라 넓어짐을 알 수 있었다. 소성변형률증분이 0인 평면변형률조건을 통해 관련유동법칙을 써서 항복함수를 구하였는데 기하하적으로 볼 때 평면응력조건에서의 항복함수가 타원임과는 달리 직선을 나타내었으며 평면응력조건일 때보다 탄성거동영역이 컸다.

• 대한치과마취과학회지
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• 제11권1호
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• pp.16-21
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• 2011

Background: Since introduced by Gow-Gates GA in 1973, Gow-Gates mandibular nerve block (GMNB) has played an important role in the area of dental local anesthesia. However, compared to the conventional inferior alveolar nerve block (IANB), this technique seems to fail to attract the attentions of general practitioners in South Korea. The aim of this study was to prove the clinical real value, mainly the anesthetic efficacy, of GMNB in minor oral surgery. Methods: The study group comprised 40 patients (15 males and 25 females) who were randomly allocated to receive GMNB or IANB for extraction of third molars. Both techniques utilized two 1.8 ml dental cartridges of 2% lidocaine including 1:100,000 epinephrine for each patient. Pulpal and gingival tissue anesthesia of mandibular premolars and molars were recorded at 0, 15 and 40 minutes after administration of local anesthetics using both an electric pulp tester and a sharp dental explorer. Results: The success rates of pulpal and gingival tissue anesthesia in the IANB group were not significantly different from the GMNB group in overall efficacy. Patient's and operator's satisfaction ratings were also not significantly different between two groups. Interestingly, the injection pain of GMNB group was significantly lower than that of IANB group. Conclusion: This study demonstrated that the anesthetic efficacy of pulpal and gingival tissue of GMNB was not inferior to that of IANB. The GMNB could be a good alternative of the IANB in most of minor oral surgical procedures.

• 비교교육연구
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• 제22권4호
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• pp.25-49
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• 2012

미국에서는 1980년대 이후 학교폭력, 무기사용, 마약복용 등의 문제에 대응하기 위하여 무관용정책(zero tolerance)을 시행하고 있다. 학교폭력이나 비행이 발생한 경우 미리 예정된 정학 또는 퇴학을 엄격하게 적용하여 학교의 안전과 학습 분위기 개선을 도모하고 있다. 실제로 학교폭력비율이 감소하고 있는 것으로 나타났다. 그러나 다른 한편으로 사소한 비행에 대해서도 엄격한 처벌을 함으로써 비행이 더 악화되며, 효용성도 증명되지 않는다는 비판이 제기되었다. 이에 대안으로 무관용정책의 대원칙은 유지하면서도 폭력의 정도에 따라 처벌의 정도를 달리하자는 등급징계제도 또는 조기반응모형이 제시되고 있다. 최근 우리나라에서도 학교폭력이 사회적 이슈로 강하게 부각됨에 따라 정부도 '학교폭력근절 종합대책'을 발표하는 등 범부처 차원에서 대응하고 있다. 이 논문은 사소한 괴롭힘도 '범죄'라는 인식하에 철저히 대응하는 정부의 방침의 타당성을 탐색하기 위해 현재 미국에서 시행하고 있는 학교폭력에 대한 무관용 정책의 주요 내용과 변화과정을 분석하여 정책적 시사점을 도출하는 데 목적이 있다.

• 미생물학회지
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• 제54권4호
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• pp.477-479
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• 2018

김치로부터 분리한 Lactobacillus koreensis 26-25 균주의 유전체서열을 분석하였다. 균주 26-25의 유전체는 G + C 비율이 49.23%이며, 2,720개의 유전자와 2,556개의 단백질 코딩 유전자, 85개의 위유전자 그리고 78개의 RNA 유전자를 포함한 단일 원형 염색체로 구성되었으면 그 크기는 3,006,812 bp였다. 균주 26-25는 인삼사포닌의 당 분해에 관여하는 여러 타입의 글라이코시다제 유전자를 가지고 있었다. 이러한 지놈 분석은 주요 진세노사이드가 우수한 약리학적 활성의 미량 진세노사이드로 전환하는데 관여하는 유전자 특징을 이해하는데 큰 기여가 되었다.

• 천문학회지
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• 제52권3호
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• pp.71-82
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• 2019

We derive the geometric albedo of a near-Earth asteroid, (4179) Toutatis, to investigate its surface physical conditions. The asteroid has been studied rigorously not only via ground-based photometric, spectrometric, polarimetric, and radar observations but also via in situ observation by the Chinese Chang'e-2 space probe; however, its geometric albedo is not well understood. We conducted V-band photometric observations when the asteroid was at opposition in April 2018 using the three telescopes in the southern hemisphere that compose the Korea Microlensing Telescope Network (KMTNet). The observed time-variable cross section was corrected using the radar shape model. We find that Toutatis has a geometric albedo $p_V=0.185^{+0.045}_{-0.039}$, which is typical of S-type asteroids. We compare the geometric albedo with archival polarimetric data and further find that the polarimetric slope-albedo law provides a reliable estimate for the albedo of this S-type asteroid. The thermal infrared observation also produced similar results if the size of the asteroid is updated to match the results from Chang'e-2. We conjecture that the surface of Toutatis is covered with grains smaller than that of the near-Sun asteroids including (1566) Icarus and (3200) Phaethon.

• 한국의료질향상학회지
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• 제28권1호
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• pp.34-44
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• 2022

Purpose:We investigated physicians' responses to a series of clinical vignettes consisting of patient safety incidents, with and without disclosure of patient safety incidents (DPSI). Methods: An anonymous survey was conducted to investigate physicians' responses to the DPSI via online communities of physicians, and additional participants were recruited using a snowballing sampling method. We evaluated physicians' responses to the DPSI using eight hypothetical scenarios (HS) from the following perspectives: thoughts regarding medical errors, revisiting the physician, recommendation, lawsuit, criminal prosecution, trust score, and compensation amounts. We used the chi-square test to evaluate the overall differences in response rates among the scenarios. Statistical analyses were performed using the Student's t-test to compare the trust scores and compensation amounts. Results: A total of 910 physicians participated in this survey. An overall comparison of trust scores among HS showed that HS 1 (unclear medical errors, minor harm, and DPSI) had the highest trust score. In contrast, in the opposite scenario, HS 8 (clear medical errors, major harm, and DPSI not conducted) received the lowest scores. Cases with minor harm to patients (HS 1, 2, 5, and 6) showed lower compensation amounts than the others (HS 3, 4, 7, and 8). Physicians were more likely to think of situations with DPSI as not having medical errors (53.1% vs. 55.2%). In addition, the scenarios with DPSI were evaluated favorably in terms of intention to revisit, recommend, suit, and engage in criminal proceedings. Physicians showed higher trust scores (6.2 vs 5.4) and gave lower compensation amounts ($27.7 million vs $28.1 million), although there was no significant difference in terms of compensation amounts to the physician conducting DPSI. Conclusion: Our study showed overall positive perceptions regarding DPSI among Korean physicians.