• 한국식품위생안전성학회지
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• 제27권2호
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• pp.133-140
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• 2012

본 연구는 중금속이 함유된 식이를 섭취 시 생체 내에서의 중금속 동태 및 함량을 구명하고자 Cd 오염 지역에서 생산된 현미를 첨가한 식이로 12주간 흰쥐를 사육하여 성장 특성과 혈액, 간 및 신장 조직의 Cd, Zn 및 Cu의 함량을 분석한 결과는 다음과 같다. 식이에 따른 일일 증가체중은 BR 및 PBR 100% 식이 군에서 0.22-0.26 g/day이었고, FE식이 군은 1.08-1.26 g/day로 식이 원에 따른 체중변화 차이가 뚜렷하였다. 식이 내 중금속 일일 섭취량은 BR+PBR 50% 및 PBR 100% 군은 10.77 및 22.36 ${\mu}g/rat$ 이고, FE+PBR 50% 군은 8.83 ${\mu}g/rat$로 식이 중 Cd 농도에 따라 일일 Cd 섭취량이 증가 되었다. 12주간 섭취한 중금속은 전체적으로 식이 중 Cd 함량이 높아지면 이들 총 섭취량도 증가되었다. BR+PBR 50% 군 및 FE+PBR 50% 군의 간과 신장의 무게는 FE 식이 군에서 2.64배 및 2.27배 높은 무게를 나타냈다. 혈액 중 Cd 함량은 BR 식이 섭취량이 많을수록 증가되었고, Zn 및 Cu 함량은 감소되었다. 동일 Cd 농도 식이 군에서 FE+PBR 50% 군은 BR+PBR 50%로 조제한 식이군보다 혈액 중 Cd 함량이 1.27배 높았다. 간에서 BR, BR+PBR 50% 및 PBR 100% 식이 군은 Cd 농도가 높으면 간 중 Cd 함량이 증가되는 현상이 뚜렷하였다. 동일 수준 농도에서 BR+PBR 50% 및 FE+PBR 50%의 Cd 축적은 BR 식이가 높았다. 신장 중 BR, BR+PBR 50% 및 PBR 100% 식이 군에서 Cd 함량의 축적이 높아지면 신장 중 Zn 및 Cu 함량이 증가하였고, 식이군의 Cd 농도가 같은 수준에서 FE와 BR 첨가 차이는 BR 첨가식이 군이 FE로 조제한 식이군보다 3.11배가 높은 Cd 함량을 나타냈다. 이와 같은 결과는 오염된 식이의 섭취량과 Cd 농도 수준에 의존한 결과로서 Zn 및 Cu 함량과도 깊은 관계가 있음을 확인하였다.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2017년도 추계학술대회
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• pp.229-231
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• 2017

오늘날 게임분야에서 PBR(Physical Based Rendering) 소프트웨어들을 이용해서 게임용 재질을 제작하는 것이 대부분이다. 예전 전통적 재질 방식에 비해 PBR 현 실무 제작파트에서 주로 사용하는 가장 큰 이유는, 굉장히 리얼한 재질을 쉽게 만들어 낼 수 있다는 것과 전통적 방식에 비해 제작의 편의성이 훨씬 뛰어난 장점 때문이다. 본 논문에서는 수많은 PBR 중, 실무에서 가장 많이 쓰이는 시스템인 MARI, QUIXEL, Substance Painter을 중심으로 각 tool의 장단점을 비교 분석함으로써 한정된 시간에 많은 양을 가르쳐야 하는 대학교에 있어서 효율적인 교육을 위해 위 세 가지 소프트웨어중 어떤 것을 취사, 선택하여 교육하는 것이 학생들에게 유리한지에 대한 분석결과를 제안하였다.

• 벤처창업연구
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• 제11권2호
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• pp.157-165
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• 2016

이 논문은 미시(微視)기반레벨에서 (at Micro-Foundations level) PBR(등급에 의한 가격책정)도구를 개발하여 PBR이 어느 상황에서든 가격책정(Pricing)의 기준과 비즈니스모델평가에 대한 일반적인 기준으로 사용될 수 있음을 주장하고 있다. 본 논문은 우선 구매력과 지불/구매의향 (Willingness to Pay/Purchase: WTP)을 동시에 지니고 있는 현시니즈(Explicit Needs)로부터 WTP모델을 유도하여 WTP수준과 WTS(willingness to supply/sell: 공급/판매의향) 수준간의 간격에 대한 서열척도(ordinal scale)를 취하여 PBR방법을 개발하였다. 구체적으로 고객이 기대하는 이상적 마케팅믹스인 최선의 SPEC (Solution, Price Indicator by WTP, Encouragement, Channel)과 기업이 제공하는 실제 마케팅믹스 (Marketing Mix) 4P에 대하여 우선 각 구성요소 마다마다를 상호 개별적으로 비교할 뿐만 아니라 전체를 하나로 인식하여 상호 비교함으로써 PBR방법을 개발한 후 이를 적용한 몇 가지 예시를 통해서 PBR방법이 실제로 비즈니스모델을 평가하는데 사용될 수 있음을 보여 준다. 결론적으로 본 논문은 어떤 상황에서든 PBR이 가격책정과 비즈니스모델의 평가도구로서 유용하게 사용될 수 있다고 주장한다.

• Journal of Microbiology and Biotechnology
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• 제26권7호
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• pp.1285-1289
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• 2016

A split-column photobioreactor (SC-PBR), consisting of two bubble columns with different sizes, was developed to enhance the photon utilization efficiency in an astaxanthin production process from Haematococcus lacustris. Among the two columns, only the smaller column of SC-PBR was illuminated. Astaxanthin productivities and photon efficiencies of the SC-PBRs were compared with a standard bubble-column PBR (BC-PBR). Astaxanthin productivity of SC-PBR was improved by 28%, and the photon utilization efficiencies were 28-366% higher than the original BC-PBR. The results clearly show that the effective light regime of SC-PBR could enhance the production of astaxanthin.

• The Korean Journal of Physiology and Pharmacology
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• 제1권5호
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• pp.523-528
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• 1997

Peripheral benzodiazepine receptor(PBR) has been indentified in various peripheral tissues including kidney. The physiological and pharmacological functions of PBR are still uncertain, althought it has been suggested that these are associated with the regulation of stress/anxiety response. Diazepam progeny, which were exposed to diazepam perinatally, was reported to be an animal model of chronic anxiety. However, PBR in the diazepam progenies are not known yet. In the present study, therefore, we examined the changes of PBR in the stress/anxiety response. Dams of rats were given injection of diazepam or vehicle during puerperium. Diazepam progenies showed increased level of anxiety on the performance of elevated plus maze, and increased Bmax of PBR. Saturation experiments followed by scatchard analysis of the results showed that the increase in the density of PBR and the affinity of the PBR remained unchanged. Forced swim stress increased anxiety on the plus maze in both groups of rats. In contrast to control, diazepam progenies did not show further upregulation of renal PBR immediately after swimming stress, but still higher than control. From the above results, it may be concluded that upregulation of renal PBR is associated with chronic anxiety as well as stress-induced response.

• Steel and Composite Structures
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• 제24권4호
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• pp.455-465
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• 2017

This paper presents a series of ultimate and fatigue experimental investigation on concrete-filled rectangular hollow section (CRHS) X joints with Perfobond Leister rib (PBR) under tension. A total of 15 specimens were fabricated, in which 12 specimens were tested under ultimate tension and 3 specimens were investigated in fatigue test. Different parameters including PBR stiffening, brace-to-chord ratio (${\beta}$) and inclined angle (${\theta}$) were considered in the test. Each joint was tested to failure under tension load. Obtained from test result, PBR was found to improve the tension strength and fatigue durability of CRHS joint substantially. Concrete dowel consisted by PBR and concrete inside the chord stiffened the joint, which leaded to a combination failure mode of punching shear and chord plastification of CRHS joint under tension. Finite element analysis validated the compound failure mode. Stress concentration on typical spot of CRHS joint was mitigated by PBR which was observed from fatigue test. Initial fatigue crack presented in CRHS joint with PBR also differentiated with the counterpart without PBR.

• Clinical and Experimental Reproductive Medicine
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• 제31권2호
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• pp.83-94
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• 2004

Objective: To investigate whether GnRH-agonist (GnRH-Ag) using in IVF-ET affects apoptosis of human granulosa-luteal cells and expression of peripheral benzodiazepine receptor (PBR) protein involved in the apoptosis of the cells. Methods: Granulosa-luteal cells obtained during oocyte retrieval were cultured and treated with $10^{-5}M$ GnRH-Ag. Apoptosis of the cells by the treatment was confirmed using DNA fragmentation analysis 24 h after culture. The presence of PBR protein within the cells was examined by immunofluorescence staining and the expression of the protein was analyzed by Western blotting. In addition, it was measured for progesterone and nitric oxide (NO) produced by granulosa-luteal cells after GnRH-Ag treatment. To evaluate the relationship between NO production and PBR expression, sodium nitroprusside (SNP) as a NO donor was added in media and investigated the expression of PBR protein by Western blotting. Results: Apoptosis increased in the granulosa-luteal cells 24 h after GnRH-Ag treatment, whereas the expression of PBR protein significantly decreased. Furthermore, the production of progesterone and nitric oxide (NO) by the cells significantly fell from 12 h after the treatment. In the results of Western blotting after SNP treatment, the expression of PBR protein increased in the treatment with SNP alone to the granulosa-luteal cells, but was suppressed in the treatment with GnRH-Ag and SNP. Additionally, the staining result of PBR protein in the cells showed the even distribution of it through the cell. Conclusion: These results demonstrate that GnRH-Ag treatment induces apoptosis, decreasing expression of PBR protein and NO production in human granulosa-luteal cells. The present study suggests that one of the apoptosis mechanism of human granulosa-luteal cells by GnRH-Ag might be a signal transduction pathway via NO and PBR.

• 한국농공학회논문집
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• 제51권5호
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• pp.1-8
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• 2009

Photobioreactor (PBR) that houses and cultivates microalgae providing a suitable environment for its growth, such as light, nutrients, CO2, heat, etc. is now getting more popular in the last decade. Among the many types of PBRs, the bubble column type is very attractive because of its simple construction and easy operation. However, despite the availability of these PBRs, only a few of them can be practically used for mass production. Many limitations still holdback their use especially during their scale-up. To enlarge the culture volume and productivity while supplying optimum environmental conditions, various PBR structures and process control are needed to be investigated. In this study, computational fluid dynamics (CFD) was economically used to design a bubble-column type PBR taking the place of field experiments. CFD is a promising technique which can simulate the growth and production of microalgae in the PBR. To study bubble column PBR with CFD, the most important factor is the possibility of realizing bubble. In this study, multi-phase models which are generally used to realize bubbles were compared by theoretical approaches and comparing in a 2D simulation. As a result, the VOF (volume of fluid) model was found to be the most effective model to realize the bubbles shape as well as the flow inside PBR which may be induced by bubble injection. Considering the accuracy and economical efficiency, 0.005 second time step size was chosen for 2.5 mm mesh size. These results will be used as criteria for scale-up in the PBR simulation.

• 한국환경과학회지
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• 제8권4호
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• pp.525-532
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• 1999

This study was conducted to evaluate capability of dyeing wastewater treatment for 3 type reactors. These reactors were Packed Bed Reactor(PBR), Fluidized Bed reactor(FBR) and Moving Media Complete Mixing Activated Sludge reactor(MMCMAS). Experiments of PBR and FBR were performed by various packing ratios and organic loading rates, experiments of MMCMAS were performed by various organic loading rates. In order to obtain ${SBOD}_5$ removal efficiencies of more than 90%, the F/Mv ratios of PBR, FBR, MMCMAS were 0.11 kgBOD/kgMLVSS$\cdot$d, 0.12 kgBOD/kgMLVSS$\cdot$d, and 0.37 kgBOD/kgMLSS$\cdot$d, respectively. So MMCMAS system which has more active microorganisms showed better capability of organic removal and also stronger dynamic and shock loadings than those of PBR and FBR. In PBR and FBR, the media packing ratio of 20% showed better performance of organic matters removal effciencies than 10% and 30%, but sludge production rate at media packing ratio of 30% was relatively lower than that of 10% and 20%. When more than 90% organic matters removal efficiency was obtained, the ratios of attached biomass to total biomass at PBR, FBR, MMCMAS were 89~99%, 87~98%, and 54~80%, respectively. The ratio of attached biomass to total biomass was low in MMCMAS. This was formation of thin biofilm due to shear force between rotaing disc and water. The average sludge production rates(kgVSS/kgBODrem.) of PBR, FBR and MMCMAS were 0.20, 0.29 and 0.54, respectively.

• KSBB Journal
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• 제7권1호
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• pp.79-83
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• 1992

Erwinia rhapontici를 Ca-alginate에 고정화시켜 고정화 세포의 반응특성을 고찰하고, STR, PBR을 이용하여 Palatinose의 생산을 검토하였다. Free cell과 고정화 세포의 반응최적 pH는 5.5-6.0, 반응 최적온도는$30-35^{\circ}C$로 동일하였으나 고정화에 의해 pH 및 온도 범위가 보다 넓어졌고, 이때 Free cell및 고정화 세포의 겉보기 Km갑슨 각각 0.13, 0.28M이었다. STR을 이용한 Palatonose 생산시 고정화 세포의 반감기는 약 380 시간으로 낮았으나, PBR을 통해 30일까지 안정운전이 가능하였다. PBR 운전시의 운전온도 30, $33^{\circ}C$에서 Palatinose수율 및 고정화 세포의 안정성은 거의 동일한 결과를 나타내었으며 이때 PBR생산성은 약 120g/l$\cdot$h이었고, Pilot scale인 50L 까지 성공적으로 Scale up 되었다.