• 한국통신학회논문지
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• 제25권6A호
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• pp.927-934
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• 2000

In this paper, we propose a predictive(transient) connection admission control(CAC) scheme for satellite systems that supports on-board packet switching of multimedia traffic with predefined quality of service(QoS) requirements. The CAC scheme incorporates the unique characteristics of satellite systems, e.g. large propagation delays, no onboard buffer, and low computational requirement. The CAC scheme requires the estimation of the On-Off traffic characteristics ($\lambda$, $\mu$) of the traffic sources. These estimated values are used to predict the transient cell loss ratio at each downlink. In case the QoS requirements are not met the proposed CAC scheme rejects the new connection. The numerical results obtained suggest that the proposed scheme is an excellent candidate for real time burst and cell level connection prediction and control in broadband on-board satellite networks.

• 한국통신학회논문지
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• 제21권3호
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• pp.675-683
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• 1996

CAC, UPC, NPC, cell level QoS and congestion control is required to assign efficiently channels's BW and to prevent networks from congestion. In the CAC algorithm, each user defines characteristics of input traffic when channels are set up and network based on this parameters determines the acception or rejection of the required BW. The CAC control mechanism is classified into the centralized BW allocation mechanism and the distributed BW Allocation mechanism according to the function and position of CAC processor allocating BW. In this paper, in contrast with esisted the distributed BW allocation mechanism which assumes the required BW of input traffic as constant, we assume input traffic & serices as bulk probability distribution in order to analyze performance more precisely.

• 식품기술
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• 제19권3호
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• pp.78-97
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• 2006

• 식품기술
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• 제19권4호
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• pp.104-131
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• 2006

• 식품기술
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• 제19권2호
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• pp.116-129
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• 2006

• 식품기술
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• 제19권2호
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• pp.130-139
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• 2006

• Tuberculosis and Respiratory Diseases
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• 제74권2호
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• pp.56-62
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• 2013

Background: The purpose of this study was to evaluate the relationship of pulmonary function impairment (PFI) and coronary artery calcification (CAC) by multi-detector computed tomography (MDCT), and the effect of pneumoconiosis on CAC or PFI. Methods: Seventy-six subjects exposed to inorganic dusts underwent coronary artery calcium scoring by MDCT, spirometry, laboratory tests, and a standardized questionnaire. CAC was quantified using a commercial software (Rapidia ver. 2.8), and all the subjects were divided into two categories according to total calcium scores (TCSs), either the non-calcified (<1) or the calcified (${\geq}1$) group. Obstructive pulmonary function impairment (OPFI) was defined as forced expiratory volume in one second/forced vital capacity ($FEV_1$/FVC, %)<70, and as $FEV_1$/FVC (%){\geq}70 and FVC<80 for restrictive pulmonary function impairment (RPFI) by spirometry. All subjects were classified as either the case (profusion${\geq}1/0$) or the control (profusion${\leq}0/1$) group by pneumoconiosis findings on simple digital radiograph. Results: Of the 76 subjects, 35 subjects (46.1%) had a CAC. Age and hypertension were different significantly between the non-calcified and the calcified group (p<0.05). Subjects with pneumoconiosis were more frequent in the calcified group than those in the non-calcified group (p=0.099). $FEV_1$/FVC (%) was significantly correlated with TCSs (r=-0.316, p=0.005). Subjects with OPFI tended to increase significantly with increasing of TCS (4.82, p=0.028), but not significantly in RPFI (2.18, p=0.140). Subjects with OPFI were significantly increased in the case group compared to those in the control group. Conclusion: CAC is significantly correlated with OPFI, and CAC and OPFI may be affected by pneumoconiosis findings.

• 동의생리병리학회지
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• 제35권5호
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• pp.169-176
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• 2021

This study was conducted to suggest the Cudrania tricuspidata leaf and Achyranthes japonica Nakai Complex (CAC) possibility of use as a functional natural material for improving bone disease. Cudrania tricuspidata leaf and Achyranthes japonica Nakai were mixed in the same amount, extracted with hot water, and then powdered and used in the study. After, the cytotoxicity of CAC for osteoblasts (MG63 cell), osteoclasts (differentiated RAW264.7 cell), and macrophages (RAW264.7 cell) were evaluated by MTT assay, and ALP assay and TRAP assay were performed to confirm the differentiation capacity of osteoblasts and osteoclasts, respectively. In addition, the anti-inflammatory effect in macrophages was evaluated by ELISA, qRT-PCR, and western blot assay. CAC did not proliferated osteoblasts and osteoclasts, but increased ALP activity against osteoblasts differentiation and decreased TRAP activity against osteoclasts differentiation. CAC did not proliferated macrophages but decreased nitric oxide production. Also, decreased NOS2, IL1B, IL6, PTGS2, and TNFA gene expression, and JNK and p38 protein phosphorylation in a concentration-dependent manner, but ERK protein phosphorylation was not changed. As a result, CAC increased the differentiation and activation of osteoblasts, inhibited the differentiation and activation of osteoclasts, and regulated the expression of inflammatory cytokines in macrophages. Therefore, it is thought that CAC can be used as a functional natural material that prevents bone disease and has an anti-inflammatory effect.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2011년도 춘계학술대회 논문집
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• pp.1305-1306
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• 2011

• 한국콘텐츠학회논문지
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• 제11권10호
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• pp.333-341
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• 2011

분진에 노출 되었던 집단을 대상으로 폐질환 선별검사를 위해 시행한 저선량 CT영상의 관상동맥 석회화 소견과 석회화수치 CT검사 결과를 비교 분석하였다. 연구윤리심의위원회의 승인과 연구대상자로부터 동의서를 받은 후, 과거 분진에 노출된 직업력을 갖고 있는 61명의 남자를 대상으로 폐질환의 선별검사를 위해 저선량 CT촬영과 석회화수치 CT검사를 동시에 실시하였다. 저선량 CT영상(Axial image)은 영상의학과 전문의로부터 진폐 소견 및 폐질환과 관상동맥 석회화소견에 대해 판독하였고, 석회화수치 CT검사로부터 얻은 기초 영상(Row image)은 별도의 워크스테이션으로 보내져 상업적인 라피디아 소프트웨어(ver 2.8)를 이용하여 관상동맥 석회화수치를 구하였다. 저선량 CT영상에서 석회화소견을 보이지 않은 그룹(42명, 68.9%)과 보인 그룹(19명, 31.1%)사이에 총 석회화(13.68 vs. 582.93, p=.009), 좌전하행관상동맥 (3.15 vs. 248.95, p=.006)의 석회화수치가 통계학적으로 유의한 차이를 보였고, 좌주관상동맥, 좌회선관상동맥, 우관상동맥에서 석회화소견을 보인 그룹에서 높게 나타났다(p>0.05). 저선량 CT영상의 석회화소견은 석회화수치 CT검사의 석회화수치 100에서 가장 높은 일치도(K-value=0.80, 95% 신뢰구간=0.69-0.91)를 보였다. 폐질환을 조기 발견하기 위해 시행된 저선량 CT영상에서 보여진 석회화소견은 석회화수치 검사결과와 높은 관련성을 보임으로써 폐쇄성 관상동맥질환을 예측할 수 있는 것으로 사료된다.