• Proceedings of the Korea Air Pollution Research Association Conference
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• 한국대기환경학회 2002년도 춘계학술대회 논문집
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• pp.43-44
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• 2002

대기오염물질 배출계수는 국가기관, 연구기관, 학계, 배출사업장, 방지시설업체, 환경영향평가사업 등 수많은 분야에서 실질적으로 활용하고 있는 자료로서 배출원에 대한 배출특성을 간접적으로 파악할 수 있을 뿐 아니라 기본부과금의 산정, 대기오염방지설비의 설계, 오염저감 계획의 수립 등에 매우 유용하게 활용 중에 있다. 그동안 국내 배출원에 대한 배출계수는 산발적으로 수행된 예가 있으나 대표성을 나타내는 자료를 확보하지 못하여 대부분의 자료를 미국(EPA AP-42) 등 선진국의 계수를 활용하고 있다. (중략)

• Proceedings of KOSOMES biannual meeting
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• 해양환경안전학회 2008년도 춘계학술발표회
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• pp.49-54
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• 2008

충돌, 좌초, 화재 등 실질적인 해양사고는 조금씩 감소하고 있지만 기관고장, 타기고장 등 단순사고는 매년 증가하고 있으며, 우리나라는 구난업체의 영세성으로 대부분의 예인구난을 해경 경비정에서 수행하고 있으나 선박예인은 사고선박의 크기, 선박고장 또는 파손상태, 기상개황에 따라서 고도의 예인기술을 필요하고 예인 중 타선박과 충돌이나 좌초, 침몰 등이 발생할 확률이 높아, 사고시 이의 인한 인적, 물적, 환경적 피해에 대한 손해배상문제 등이 대두 될 수 있어, 예인구난에 대한 관련법령 및 제도를 재검토하여 해상 예인구난체제 개선방안을 제시하였다.

• Investigative Magnetic Resonance Imaging
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• 제12권2호
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• pp.170-177
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• 2008

Purpose : To evaluate usefulness of MR imaging after serial brain US in the high-risk neonates before discharge of the neonatal intensive care unit. Materials and Methods : Retrospective comparison of 412 US and 121 MR scans in 121 neonates and young infants were performed. Grading of germinal matrix/intraventricular hemorrhage (GMH/IVH) was performed and presence of intracranial hemorrhage other than GMH/IVH and parencyma lesions was also analyzed. Results : Among the 242 lateral ventricles, Seven GMH and 46 IVH were additionally detected by MRI. On the other hand, 30 GMH were only detected by US. US demonstrated Grade 1/2/3/4 GMH/IVH in 24/8/13/0 ventricles each, while each grades were identified in 3, 49, 10, 2 ventricles on MR images. Other intracranial lesions additionally detected on MR images were cerebral hemorrhage (n=4), cerebellar hemorrhage (n=4), extraaxial hemorrhage (n=8), diffuse excessive signal change of the white matter (n=72), non-cavitary lesion (n=4), encephalomalacia (n=2), and ventriculomegaly (n=5). Conclusion : MR imaging could be an excellent complimentary study after serial brain US for additional detection of the intracranial pathology, particularly IVH and white matter lesions, though US would be better in follow-up of GMH in some neonates.

• Journal of Navigation and Port Research
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• 제35권5호
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• pp.351-358
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• 2011

Recently, tugs and barges have become larger in size and increased in number. Also, most of tugs and barges are more than ten-years old. Total number of marine accident has been decreased, whereas that of accidental happening in tug-barge transportation has not been decreased. The statistics of marine accidents in 2010 shows that tug-barge accidents increased rapidly compared with those of 2009. The cause of accidental happening in tug-barge transportation is a quality of tug-barge operator the labour serious shortage of crew. This study is to give or suggest the various educational contents considering old age of crew and navigational environment for safe navigation in tug-barge transportation.

• Archives of design research
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• 제15권3호
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• pp.103-114
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• 2002

Recently, it is more important to do part of software designers for developing user-centered software. They produce visual document for helping communication between developers and visual diagram for analyzing user need factors based on user scenario. Case study of architecture real dispatch service can show developing samples. It is important to produce visual document for one combined opinion between developers in process of defining of development boundary, main concept development, selecting of development system. And visual document process with visual language by software designer is step for recognizing of user need factors before developing interface design in process of collecting design factors of user and environment and analyzing design factor by user scenario. Also, in process of interface and prototype development, it need visual document for peaceful and concord process between developers. Those visual documents with visual language could help to define developers role and duty, user-centered concept development and various interface development proposal during software developing.

• Proceedings of the Korea Institutes of Information Security and Cryptology Conference
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• 한국정보보호학회 2003년도 하계학술대회논문집
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• pp.219-222
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• 2003

기존 운영체제 시스템의 취약점을 극복하기 위한 방안으로 기존 운영체제에 보안 커널을 추가한 Secure OS 이다 본 논문은 Secure OS의 특징인 Access Control기능에 대하여 조사 분석하여 사용자의 권한의 최소화를 연구하였다. 그리고 실질적인 공격 예로서 공격자가 ROOT 권한을 획득하였을 경우 Secure OS는 기존 OS보다 안전하다는 것을 연구하였다. Secure OS 제품은 (주)시큐브의 Secuve TOS제품을 사용하여 테스트하였다.

• Investigative Magnetic Resonance Imaging
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• 제4권1호
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• pp.34-41
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• 2000

Purpose: To evaluate the clinical usefulness of diffusion weighted MR imaging(DWI) in the differential diagnosis of brain tumors. Materials and methods: DWI and conventional MR images of nineteen patients with brain tumors(10 metastatic tumors, 4 high grade gliomas, 4 low grade astrocytomas, one oligodendroglioma)were obtained on 1.5T unit. DWI was obtained using single shot spin echo planar imaging with b-value near 1000. We analyzed the signal intensities of lesions including solid portion, necrotic or cystic portion and peritumoral edema of brain tumors (classified five grades comparison with the signal intensities of brain parenchyma and CSF)and calculate the SIR(signal intensity ratio)of lesions to the contralateral normal brain parenchyma. We analyzed statistically the signal intensities and SIR of tumors using independence T test. Results: In solid portions of tumors, all the metastatic tumors and high grade gliomas showed high signal intensities, but low grade astrocytomas and oligodendroglioma showed iso or slight high signal intensities to the normal brain parenchyma. The SIR of solid portion has positive correlation with malignant pot ential(metastatic tumors 1.52, high grade gliomas 1.38, low grade astrocytomas 1.16, oligodendroglioma 1.31)(p < 0.05). In peritumoral edema where seen in 14 tumors, seven of 10 metastatic tumors and two of 4 high grade gliomas showed iso signal intensities, whereas edemas in other 5 brain tumors showed hyperintense to the normal brain parenchyma. The SIRs of peritumoral edemas in metastatic tumors (1.14) was lower than high grade gliomas(1.31),but statistically insignificant. The SIR of cystic or necrotic portion of brain tumors was 0.63. In non enhancing solid portions, three of six cases showed hyperintense to the adjacent peritumoral edema. Conclusion: On DWI, the signal intensities of solid portion has positive correlation with malignant potential, and perilesional edema of brain tumors appear various signal intensities owing to "T2 shine through effect" and the extensiveness of vasogenic edema. Another merit using DWI on the evaluation of brain tumors is to improved better delineation of tumor margins from the adjacent edemas, especially at the non enhancing solid portion of the tumors.

• Investigative Magnetic Resonance Imaging
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• 제6권1호
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• pp.21-27
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• 2002

Purpose : To evaluate diffusion-weighted imaging findings of intracerebral hematoma according to the time sequence. Materials and methods : Seventeen patients with intracerebral hematoma were studied. Diffusion weighted images using 1.5 tesla MRI machine were obtained with b-value of $1000{\;}sec/\textrm{mm}^2$. The patients were grouped as hyperacute stage(within 12 hours, 5 patients), acute stage(within 3 days, 4 patients), subacute stage(within 3 weeks, 4 patients), and chronic stage(after 3 weeks,4 patients). The signal intensities were analysed as bright, high, iso, low and dark at the central and peripheral portions of the hematoma in each stage, and compared with those of T2 and T1 weighted images. Results : The signal intensities of the central and peripheral portion of the intracerebral hematoma on diffusion-weighted images were high and dark in hyperacute stage, dark and high-bright in acute stage, and high-bright and dark in subacute and chronic stages. The patterns of signal change of hematoma on diffusion-weighted image according to the time sequence were similar to those on T2-weighted image, but changed early and prominently. Conclusion : The intracerebral hematoma on diffusion-weighted image showed unique central and peripheral signal intensity according to the time sequence. Central portions show high to bright signals in hyperacute, subacute and chronic stage, and dark signal in acute stage, and peripheral portions show dark signals in hyperacute, subacute and chronic stage, and high to bright signal in acute stage.

• The Journal of Korean Institute of Communications and Information Sciences
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• 제23권5호
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• pp.1222-1228
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• 1998

Most of researchers have tried to find heuristic methods for near-optimal solutions of establishing light paths with minimum number of wavelengths in wavelengh-routed optical networks. In order to provide a performance measure for heuristic approaches, we propose a practical approach for a lower bound of the number of wavelengths which is required to provide full connections in WDM-based optical transport networks. This method is based on a path-flow formulation using K-shortest paths for each connection. Compared with a general link-flow formulation, the proposed method has much lower complexity and so needs much less calcuation tiem while it gives the same results as a general link-flow formulation in some sample networks.

• The Optical Journal
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• 통권133호
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• pp.53-60
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• 2011

광학세계에서는 일본 캐논의 연구개발부장을 지낸 말전철부(末田哲夫)씨가 집필한 <광학부품의 사용법과 유의점>이란 책 내용을 연재하고 있다. 본 내용은 일본의 월간 OPTRONICS에서 1982년부터 30회에 걸쳐 연재된 바 있고, 연재한 내용만 묶어 한 권의 책으로 나온 이후 지금까지 많은 광학인들이 애독하고 있는 핸드북이다. 월간 OPTRONICS는 1990년에 책 내용을 세부에 걸쳐 수정함과 동시에 렌즈에 대한 기초를 보다 충실히 하고 비구면 렌즈, Rod 렌즈, 홀로그램, 고체 촬상디바이스, 회절광간섭방식 엔코더 등을 새롭게 첨가하여 보다 알찬 내용으로 보강하여 증보개정판을 내놓았다. 국내에서는 (주)그린광학에서 본 자료를 입수하여 사내자료로 활용하고 있을만큼 시대와 장소를 초월하여 아직도 광학산업현장에서 유용한 자료로 읽혀지고 있다. 비록 일부 내용들은 우리 나라 산업현실과 다소 차이가 있는 부분도 있을 것이나 광학기술의 역사와 기반이 앞서있다고 생각되는 일본의 실질적인 기술관련 자료이기 때문에 국내 업체 관련분야에 종사하시는 분들에게 일독을 권해드리고 싶은 마음에 광학세계에서도 2009년 7월호부터 연재를 하게 되었다. 전체 내용을 살펴보면, 제1부에는 대표적인 광학부품에 대한 설명, 제2부에는 그것들을 사용한 광학시스템과 그것들에 관한 기본적인 사항의 해설, 제3부에는 광학부품을 수입하는 경우의 측정방법과 그것들을 시스템으로 조립하는 경우의 조정방법 예 등을 소개했다. 기술 내용은 응용범위가 넓다고 생각되는 구체적인 예를 기본으로 소개했다.