• TTA 저널
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• 통권36호
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• pp.51-62
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• 1994

• 한국통신학회논문지
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• 제26권12C호
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• pp.240-248
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• 2001

본 논문에서는 현재 우리 나라의 초고속 국가기간전송망의 기본 전송장비인 2.5Gb/s SDH 전송시스템에 적용되어 2-선 양방향 선로 스위칭 링의 자기치유동작을 가능하게 하는 공간분할스위치 소자의 설계와 시스템에의 적용을 다룬다. Compass tool로 설계된 스위치 소자는 1.25Gb/s의 스위치 처리용량을 가지며 0.8$\mu\textrm{m}$ CMOS gate-array로 제작되었다. 제안된 스위치 소자는 2-선 양방향 전송선로 상에 장애가 발생했을 때 신속한 자기치유동작을 가능하게 한다. 스위치의 구조는 Add/Drop 제어부, Cross-point switch, 데이터 프레임 위상 정렬부, 비장착(Unequipped) 신호 프레이머부, 프로세서 접속부 등으로 구성된다. 제작된 2개의 스위치를 병렬구조로 구성하여 2.5Gb/s SDH 전송시스템에 적용하여 시험한 결과 임의의 광선로 장애 시 신호채널들의 링 스위칭 동작으로 즉시 복구가 가능함을 보여준다.

• Journal of Korean Neurosurgical Society
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• 제59권5호
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• pp.498-504
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• 2016

Objective : Although subdural hematoma (SDH) is commonly treatable by burr hole surgery in the late subacute or chronic stage, there is no clear consensus regarding appropriate management and exact predictive factors for postoperative recurrence also remain unclear. The aim of this study was to evaluate risk factors associated with recurrence of SDH that requires burr hole surgery in the late subacute or chronic stage. We also identified the appropriate timing of surgery for reducing the recurrence. Methods : We retrospectively reviewed 274 patients with SDH in the late subacute or chronic stage treated with burr hole surgery in our hospital between January 2007 and December 2014. Excluding patients with acute intracranial complications or unknown time of trauma onset left 216 patients included in the study. Results : Of 216 patients with SDH in the late subacute or chronic stage, recurrence was observed in 36 patients (16.7%). The timing of the operation in patients with late subacute stage (15-28 days) resulted in a significant decrease in recurrence (RR, 0.33; 95% CI, 0.17-0.65; p=0.001) compared to chronic stage (>28 days). Otherwise, no significant risk factors were associated with recurrences including comorbidities and surgical details. Conclusion : The results indicated that time from trauma onset to burr hole surgery may be important for decreasing the risk of recurrence. Therefore, unless patients can be treated conservatively without surgery, prompt surgical management is recommended in patients diagnosed as having late subacute or chronic subdural hematoma treatable by burr hole surgery, even when neurological deficits are unclear.

• Journal of Korean Neurosurgical Society
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• 제50권1호
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• pp.6-10
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• 2011

Objective : Spontaneous acute subdural hematomas (aSDH) secondary to ruptured intracranial aneurysms are rarely reported. This report reviews the clinical features, diagnostic modalities, treatments, and outcomes of this unusual and often fatal condition. Methods : We performed a database search for all cases of intracranial aneurysms treated at our hospital between 2005 and 2010. Patients with ruptured intracranial aneurysms who presented with aSDH on initial computed tomography (CT) were selected for inclusion. The clinical conditions, radiologic findings, treatments, and outcomes were assessed. Results : A total of 551 patients were treated for ruptured intracranial aneurysms during the review period. We selected 23 patients (4.2%) who presented with spontaneous aSDH on initial CT. Ruptured aneurysms were detected on initial 3D-CT angiography in all cases. All ruptured aneurysms were located in the anterior portion of the circle of Willis. The World Federation of Neurosurgical Societies grade on admission was V in 17 cases (73.9%). Immediate decompressive craniotomy was performed 22 cases (95.7%). Obliteration of the ruptured aneurysm was achieved in all cases. The Glasgow outcome scales for the cases were good recovery in 5 cases (21.7%), moderate disability to vegetative in 7 cases (30.4%), and death in 11 cases (47.8%). Conclusion : Spontaneous aSDH caused by a ruptured intracranial aneurysm is rare pattern of aneurysmal subarachnoid hemorrhage. For early detection of aneurysm, 3D-CT angiography is useful. Early decompression with obliteration of the aneurysm is recommended. Outcomes were correlated with the clinical grade and CT findings on admission.

• Membrane and Water Treatment
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• 제9권4호
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• pp.273-278
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• 2018

Due to the lack of water in arid and semi-arid areas, reuse of wastewater can be a suitable way to compensate for water scarcity. Therefore, in this research, evaluation of the quality of wastewater of Kashan Treatment Plant to use for irrigation was studied. This descriptive cross-sectional study was conducted in 2016. pH, TSS, TDS, turbidity, COD, BOD5, Total Kjeldahl Nitrogen, Total Phosphorus, Total Coliform, fecal coliform, nematode eggs of inlet and outlet of wastewater treatment plant in Kashan were studied. Mean and standard deviation and wastewater quality parameters before and after treatment were tested with SPSS 22 (2014) software. The mean wastewater output of COD, BOD5, TSS, TDS and turbidity were respectively 86.6, 41.2, 11.11, 1095 mgL-1 and 17.5 NTU and the pH was equal to 7.22. Also, the average of Total Kjeldahl Nitrogen and phosphorus were 22.4 and 2.2 mgL-1 respectively. The mean of Total Coliform and fecal coliform were 225, 161 MPN / 100 ml respectively. In addition, no nematode eggs were found in final effluent. The results indicated that the treatment plants had a significant role in the control of microbial and organic pollution load of wastewater. Also, it is concluded that all parameters were in accordance with the standards of Iran's Department of Environment, so, it can be used for unrestricted irrigation.

• 터널과지하공간
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• 제12권4호
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• pp.268-276
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• 2002

In this study, a 3D coordinate measurement system equipped with a laser displacement meter for digitizing rock joint surface was established and the digitized data were used to calculate several roughness parameters. The parameters used in this study were micro avenge inclination $angle(i_{ave})$, average slope of joint $asperity(SL_{ ave})$, root mean square of $i-angle(i_{rms})$, standard deviation of height(SDH), standard deviation of $i-angle(SD_i)$, roughness profile $index(R_P)$, and fractal dimension(D). The relationships between the roughness parameters based on the digitzation of the surface profile were analyzed. Since the measured value varied according to the degree of reflection and the variation of colors at the measuring point, rock joint surface was painted in white to minimize the influence of the surface conditions. The comparison of the measured values and roughness parameters before and after painting revealed the better consequence from measurement on the painted surfaces. Also, effect of measuring interval was studied. As measured interval was increased, roughness parameters were exponentially decreased. The incremental sequence of degree of decrease was $SDH\; i_{ave},\; i_{rms},\; SD_i,\;and\; R_ p-1$. As a result of comparison of parameters from pin-type measurement system and laser type measurement system, all value of parameters were higher when laser-type measurement system was used, except SDH.

• 한국통신학회논문지
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• 제22권9호
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• pp.2062-2073
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• 1997

동기식 전송망과 장치를 설계할 때 고려해야 할 중요사항은 최대 노드수와 노드의 클럭특성이다. 이를 위해서는 클럭상태가 정상상태일 때 뿐 아니라 단기위상순서변위, 그리고 장기위상변위 등에 관한 클럭특성 연구가 필요하다. 따라서 본 논문에서는 국내 동기클럭 분배망의 구성을 바탕으로 최근 확정된 ITU-T 및 ANSI의 클럭규격을 적용하여 동기식 선형망에서 정상상태와 위상변위상태일 때의 망구성에 따른 MTIE 및 TDEV 특성을 살펴보았고, ITU-T와 ANSI규격을 동시에 만족하는 최대 노드수를 제시하였다. 또한 본 논문에서 얻은 결과를 AT&T의 것과 비교 분석하였다.

• 한국통신학회:학술대회논문집
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• 한국통신학회 1994년도 하계종합학술발표회 논문집
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• pp.560-563
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• 1994

• 한국통신학회:학술대회논문집
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• 한국통신학회 1996년도 추계종합학술발표회 논문집
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• pp.1146-1149
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• 1996

• 한국통신학회:학술대회논문집
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• 한국통신학회 1993년도 추계종합학술발표회 논문집
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• pp.62-66
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• 1993