• 천문학회보
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• 제43권1호
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• pp.44.1-44.1
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• 2018

We present a spectroscopic study of the Galactic supernova remnant (SNR) Cygnus Loop using the fifth Data Release (DR5) of LAMOST. The LAMOST (Large Sky Area Multi-Object Fiber Spectroscopic Telescope) features both a large field-of-view (about 20 deg2) and a large aperture (~4 m in diameter), which allow us to obtain 4000 spectra simultaneously. Its wavelength coverage ranges from ${\sim}3700{\AA}$ to $9000{\AA}$ with a spectral resolution of $R{\approx}1800$. The Cygnus Loop is a prototype of middle-aged SNRs, which has advantages of being bright, large in angular size (${\sim}3.8^{\circ}{\times}3^{\circ}$), and relatively unobscured by dust. Along the line of sight of the Cygnus Loop, 2747 LAMOST DR5 spectra are found in total, which are spatially distributed over the entire remnant. Among them, 778 spectra are selected based on the presence of emission lines (i.e., [O III]${\lambda}5007$, Ha, and [S II]${\lambda}{\lambda}$ 6717, 6731) for further visual inspection. About half of them (336 spectra) show clear spectral features to confirm their association with the remnant, 370 spectra show stellar features only, and 72 spectra are ambiguous and need further investigation. For those associated with the remnant, we identify emission lines and measure their intensities. Spectral properties considerably vary within the remnant, and we compare them with theoretical models to derive physical properties of the SNR such as electron density and temperature, and shock velocity. While some line ratios are in good agreement with model prediction, others cannot be explained by simple shock models with a range of shock velocities. We discuss these discrepancies between model predictions and the observations and finally highlight the powerfulness of the LAMOST data to investigate spatial variations of physical properties of the Cygnus Loop.

• Imaging Science in Dentistry
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• 제37권3호
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• pp.139-147
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• 2007

Purpose: To assess bone changes of mandibular condyle using cone beam computed tomography (CBCT) in temporomandibular disorder (TMD) patients. Materials and Methods: 314 temporomandibular joints (TMJs) images of 163 TMD patients were examined at the Department of Oral and Maxillofacial Radiology, Chonbuk National University. The images were obtained by PSR9000N (Asahi Roentgen Co., Japan) and reconstructed by using Asahivision software (Asahi Roentgen Co., Japan). The CBCT images were examined three times with four weeks interval by three radiologists. Bone changes of mandibular condyle such as flattening, sclerosis, erosion and osteophyte formation were observed in sagittal, axial, coronal and 3 dimensional images of the mandibular condyle. The statistical analysis was performed using SPSS 12.0. Intra- and interobserver agreement were performed by 3 radiologists without the knowledge of clinical information. Results: Osteophyte (2.9%) was found more frequently on anterior surface of the mandibular condyle. Erosion (31.8%) was found more frequently on anterior and medial surfaces of the mandibular condyle. The intraobserver agreement was good to excellent (k=0.78-0.84), but interobserver agreement was fair (k=0.45). Conclusion: CBCT can provide high qualified images of bone changes of the TMJ with axial, coronal and 3 dimensional images.

• 한국건설관리학회논문집
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• 제8권5호
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• pp.119-131
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• 2007

건설 프로젝트에서 설계시공 일괄방식은 프로젝트에 참가하는 모든 참여자가 협력하기 때문에 일관성, 공기단축, 품질향상, 프로젝트 요구를 만족시키는 설계의 혁신과 같은 효과를 기대할 수 있는 발주방식이다. 서구에서 일괄방식은 우수한 발주방식을 찾고자 하는 노력의 결과로 보고 있으며, 성과분석 결과 공기단축, 비용절감, 품질향상 등이 분리방식에 비하여 우수한 것으로 입증되어 발주가 확대되고 있다. 일괄방식은 1975년 국내에 도입되어 9000년까지 공공부문 전체 프로젝트의 10% 이하에만 적용되었으나, 이후부터 지속적으로 증가하여 2005년에는 26%까지 그 적용이 증가하였다. 이에 본 연구에서는 건설통계분석, 발주방식 성과분석, 설문조사를 바탕으로 시스템 다이내믹스 인과지도를 작성하여 그 원인을 분석하고 서구에서와 같이 우수한 발주방식으로 정착되기 위한 정책적 개선방안을 제시하고자 한다.

• Journal of the Korean Wood Science and Technology
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• 제15권2호
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• pp.99-104
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• 1987

Fiber mats were made at various density levels, using fibers from papermill sludge, ricestraw and various mixtures of the two. The paper mill sludges were collected from Moorim Papermill Co, and Jeonjoo Papermill Co. They were soaked in the liquid sulfur compounds, sulfur-tall oil and sulfurpolyester compounds, and made into fiber-reinforced, sulfur-based composition board. Under optimum conditions of fiber mat preparation and saturation with molten sulfur and modified sulfur, the Young's moduls of the manufactured tiber-reinforced composition board are superior to those of conventional wood-based composition boards. For example, the moduli of elasticity of the composition board made from papermill sludge, with a density of 0.40gm/$cm^3$, were greater than 1,400,000psi as compared 800,000psi for high density hardboard(1.28gm/$cm^3$). The modulus of rupture of the best reinforced composition board manufactured was over 9000psi, comparable to 6000psi of high density hardboard. The proposed Bryant and Lee's theory, "Modified Rule of Mixtures" can be applicable to the nonoriented and short fibrous composition board, when it was modified from "Rule of Mixtures" established by Paul an Jones, and supplemented by Smith and Cox's theory, In the Bryant and Lee's theory of $E_c=\frac{1}{3}aE_fV_f+bE_mV_m$, the constants "a" and "b" for the composition boards made from papermill sludge and the mixtures of ricestraw and the sludge were identified to be in the ranges of 3.29~3.54 and -2.47~-2.80 respectively.

• Imaging Science in Dentistry
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• 제37권2호
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• pp.103-110
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• 2007

Purpose: To examine the danger zone of mesial root of mandibular first molar of patient without extraction using CBCT (cone-beam computed tomography) to avoid the risk of root perforation. Materials and Methods: 20 mandibular first molars without caries and restorations were collected, CT images were obtained by CBCT ($PSR9000N^{TM}$, Asahi Roentgen Co., Japan), reformed and analyzed by V-work 5.0 (CyberMed Inc., Korea), Distance between canal orifice and furcation was measured. In cross sectional images at 3, 4 and 5 mm below the canal orifice, distal wall thickness of mesiobuccal canal (MB-D), distal wall thickness of mesiolingual canal (ML-D), distal wall thickness of central part (C-D), mesial wall thickness of mesiobuccal canal (MB-M) and mesial wall thickness of mesiolingual canal (ML-M) were measured, Results: The mean distance between the canal orifice and the furcation of the roots is 2.40 mm, Distal wall is found to be thinner than mesial wall. Mean dentinal wall thickness of distal wall is about 1 mm, The wall thickness is thinner as the distance from the canal orifice is farther. But significant differences are not noted between 4 mm and 5 mm in MB-D and C-D, MB-D is thinner than ML-D although the differences is not significant. Conclusion: The present study confirmed the anatomical weakness of distal surface of the coronal part of the mesial roots of mandibular first molar by CBCT and provided an anatomical guide line of wall thickness during endodontic treatment.

• Annals of Laboratory Medicine
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• 제38권6호
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• pp.512-517
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• 2018

Background: Complete blood count (CBC) results play an important role in peripheral blood smear (PBS) examinations. Many descriptions in PBS reports may simply be translated from CBC parameters. We developed a computer program that automatically generates a PBS draft report based on CBC parameters and age- and sex-matched reference ranges. Methods: The Java programming language was used to develop a computer program that supports a graphical user interface. Four hematology analyzers from three different laboratories were tested: Sysmex XE-5000 (Sysmex, Kobe, Japan), Sysmex XN-9000 (Sysmex), DxH800 (Beckman Coulter, Brea, CA, USA), and ADVIA 2120i (Siemens Healthcare Diagnostics, Eschborn, Germany). Input data files containing 862 CBC results were generated from hematology analyzers, middlewares, or laboratory information systems. The draft reports were compared with the content of input data files. Results: We developed a computer program that reads CBC results from a data file and automatically writes a draft PBS report. Age- and sex-matched reference ranges can be automatically applied. After examining PBS, users can modify the draft report based on microscopic findings. Recommendations such as suggestions for further evaluations are also provided based on morphological findings, and they can be modified by users. The program was compatible with all four hematology analyzers tested. Conclusions: Our program is expected to reduce the time required to manually incorporate CBC results into PBS reports. Systematic inclusion of CBC results could help improve the reliability and sensitivity of PBS examinations.

• 산업진흥연구
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• 제7권1호
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• pp.75-80
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• 2022

崔溥（公元1454~1504),字淵淵,號錦南。曾任李氏朝鮮弘文館副校理（五品官員),1487年赴濟州島執行公務,期間因其父亡故,故於1488年閏正月初三回家奔喪,卻不幸在途中遭遇暴風雨,所乘船舶受損,致其在海上漂流了近半月之久。後其在「大唐國浙江台州府臨海縣界」(今三門縣)登陸後經陸路到達杭州,後於杭州乘船沿京杭大運河經水路至北京。明朝弘治皇帝親自接見並賞賜了崔溥後,從北京走陸路過山海關,經鴨綠江返回了自己的國家。崔溥在中國滯留了4個半月,136天,行程將近9000里地。回國後,他用漢文寫出了《漂海錄》一書,這部以日記體形式的著作共5萬余字,一定程度上記錄了明朝弘治初年中國京杭運河流域的地理,城市,民俗等方面內容,為後世研究明朝時期的政制,司法,運河,城市,地志,民俗以及海防提供了重要的文獻記錄。

• 한국프랜차이즈경영연구
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• 제2권2호
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• pp.134-149
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• 2011

최근 들어 기업의 사회적 책임(CSR)에 관한 기업과 학자들의 관심이 갈수록 증대하고 있다. 기업의 사회적 책임의 속성 중 일반적으로 기업의 역할론을 집중적으로 조명하고 있다. 더욱이 국제표준화기구(ISO)가 기업의 실제적 규범으로ISO900, ISO1400을 지정한 후, 2010년 11월 ISO가 ISO26000을 기업의 사회적 책임의 새로운 가이드라인으로 선언하면서 그 중요성이 훨씬 증대되었다. 경제전환시대에 이르러, 중국에서도 기업의 사회적 책임에 관한 중요성이 날로 증가하고 있다. 2011년 중국사회과학원의 '중국기업의 사회책임에 관한 보고'에 의하면, 중국기업의 사회책임수준은 초기단계로서, 아직까지 낮은 수준에 머무르고 있다. 특히 베이징은 중국의 수도로서 정치, 문화, 국제, 중국내 교류 중심지로서, 중국에서 가장 큰 소매시장이 형성되었고, 세계 10대 소비도시로 소매기업이 꾸준히 발전하고 있다. 그러나 아직까지 베이징 소매기업에 대한 기업의 사회적 책임에 관한 관리모형에 대한 연구가 부족한 현실이다. 본 논문은 중국 및 베이징의 소매기업의 사회적책임에 관한 관리현황을 파악하였다. 그리고 정부주도하의 베이징의 소매기업의 사회적 책임 관리모형을 4개 측면에서 수립하였다. 또한 기업이 계속적인 경쟁력을 유지하기 위해 소매기업의 사회적 책임을 수행할 수 있도록 5가지 시행방안을 제안하였다.

• Anatomy and Cell Biology
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• 제56권1호
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• pp.86-93
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• 2023

Age at death estimation has always been a crucial yet challenging part of identification process in forensic field. The use of human skeletons have long been explored using the principle of macro and micro-architecture change in correlation with increasing age. The clavicle is recommended as the best candidate for accurate age estimation because of its accessibility, time to maturation and minimal effect from weight. Our study applies pre-trained convolutional neural network in order to achieve the most accurate and cost effective age estimation model using clavicular bone. The total of 988 clavicles of Thai population with known age and sex were radiographed using Kodak 9000 Extra-oral Imaging System. The radiographs then went through preprocessing protocol which include region of interest selection and quality assessment. Additional samples were generated using generative adversarial network. The total clavicular images used in this study were 3,999 which were then separated into training and test set, and the test set were subsequently categorized into 7 age groups. GoogLeNet was modified at two layers and fine tuned the parameters. The highest validation accuracy was 89.02% but the test set achieved only 30% accuracy. Our results show that the use of medial clavicular radiographs has a potential in the field of age at death estimation, thus, further study is recommended.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제45회 하계 정기학술대회 초록집
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• pp.205-205
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• 2013

테라헤르쯔(terahertz: THz)파는 0.1~10 THz 의 범위로 적외선과 방송파 사이에 광대역 주파수 스펙트럼을 차지하고 있으며 직진성, 투과성, 그리고 낮은 에너지 (meV)를 가지고 있어 비 파괴적이고 무해한 장점을 지니고 있다. Ti:sapphire laser와 같은 femto-pulse source 등이 많은 발전이 되어 현재 많은 연구와 발전이 이루어지고 있다. femto-pulse source를 이용한 THz 응용에서는 높은 저항, 큰 전자 이동도, 그리고 아주 짧은 전하수명의 기판을 요구하는데 저온에서 성장한 (low-temperature grown : LT) GaAs는 격자 내에 Gallium 자리에 Arsenic이 치환 하면서 AsGa antisite가 발생하여 전하수명을 짧아지는 것을 응용하여 가장 많이 이용되고 있다. 현재 THz 응용분야에서 보다 작고 가격경쟁력이 있는 광통신을 이용한 THz photomixer등이 활발히 연구 하고 있다. 광섬유 내에서 손실과 분산이 최소값을 가지는 부분이 1.55 ${\mu}m$ 부근이고 In0.53Ga0.47As 기판을 이용하였을 때 여기에 완벽하게 만족하게 된다. 하지만 LT-InGaAs 의 경우 AsGa antisite로 인하여 carrier lifetime은 짧아지지만 높은 n-type 전하밀도를 가지게 된다. 이때 Be을 doping하여 전하밀도를 보상하여 높은 저항을 유지해야 하는데 Be의 활성화를 위해서는 열처리를 필요로 한다. 하지만 열처리를 하면 carrier lifetime이 길어지기 때문에 carrier lifetime과 저항을 적절히 조율해야 한다. 이는 물질자체의 특성이기 때문에 InGaAs는 GaAs보다 낮은 amplitude와 짧은 cut-off frequency를 가진다. 본 연구에서는 보다 높은 저항을 얻기 위하여 molecular beam epitaxy를 이용하여 semi-insulating InP:Fe 기판위에 격자 정합된 InGaAs:Be/InAlAs multi quantum well (MQW)를 온도별 ($250{\sim}400^{\circ}C$), 주기별 (50~150)로 성장을 하였고 이때 InGaAs layer의 Be doping level은 $2{\times}1018\;cm^{-3}$, Ex-situ annealing은 $550^{\circ}C$에서 10분으로 고정 하였다. THz 발생 실험에서는 InGaAs/InAlAs MQW은 4000 pA로 1,000 pA를 가지는 InGaAs epilayer보다 4배 높은 전류 신호를 얻을 수 있었고 모든 샘플이 2 THz에서 cut-off frequency를 가지고 있었다. THz 검출 실험에서는 LT-InGaAs:Be epilayer LT-InGaAs:Be/InAlAs, HT-InGaAs/InAlAs 샘플이 각각 180, 9000, 12000 pA의 전류신호를 가지고 있었고 모든 샘플이 2 THz에서 cut-off frequency를 가지고 있었다. HT-InGaAs/InAlAs MQW를 이용한 검출실험에서는 InGaAs layer가 defect free이지만 LT-InGaAs:Be/ InAlAs MQW 보다 높은 전류 신호를 얻을 수 있었다. 이는 InAlAs layer가 저항만 높이는 것뿐만 아니라 carrier trapping layer로써의 역할도 하는 것으로 사료된다.