• 임산에너지
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• 제19권1호
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• pp.1-6
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• 2000

본 연구는 소나무(Pinus densifora S. et Z.) 유묘의 발아전 단계, 자엽 단게 및 1차엽 발생후 단계 등 각각의 생육단계에서의 UV-B 증가 환경에 노출될 때의 생장반응을 탐구하고자 16주 동안 3수준의 UV-B(ambient UV-BBE, ambient + 3.2, ambient + 5.2 KJm-2s-1) 조사량이 설치된 야외 포장에서 실시되었다. UV-B 조사에 의하여 소나무 유묘의 수고생장, 근원경생장 및 건물생산량은 감쇠되었으며 T/R율은 증가하였다. 유묘에 대한 UV-B 처리시작 단계 차이에 따른 생장차이도 관찰되었는데, ambient +3.2 처리구내에서 보면 발아전 단계부터 UV-B 처리를 받은 유묘의 수고생장 및 근원경생장이 상대적으로 높았다. 주 수준의 UV-B 증가 처리구에서 모두 자엽단계부터 처리를 잗은 유묘의 건물생산량이 각 처리구내에서 가장 낮앗다. 한편 UV-B 증가에 의해 소나무 유묘 침엽의 엽롭소 함량은 감소하였으며 엽록소 a/b율은 증가하였다.

• 한국세라믹학회지
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• 제36권5호
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• pp.471-477
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• 1999

Fe and Fe-Mo binder were used to produce TiB2 based cermet by a pressureless sintering. The densification behaviour of TiB2-Fe-Mo cermet during liquid-phase sintering in argon was studied in relation to binder phase charactertics. The effects of Mo addition and sintering condition on the sintering behaviour and mechanical properties were also investigated. TiB2-based cermets with Fe-Mo binder composition showed a better sinterability than the cermets with only Fe binder. In TiB2-Fe-Mo cermet higher densities in the wide temperature range were obtained and also fully densified sintered cermet were obtained at 1873K The enhancement in the densification phenomenon of TiB2-Fe-Mo system can be explained by improved liquid phase wettability associated with the roles of Mo components as solute atoms. When Fe-Mo binders were used cermets with a finer grain size and enhanced mechanical properties wereproduced and new phases such as Fe2B and Mo2FeB2 were observed in the sintered cermet. The highest bending strength was obtained from the 20vol% Fe-Mo cermet and these hardness-fracture toughness combination in the wide binder compositions is better than that of TiB2-Fe cermet. In order to improve mechanical properties microstructure control with high purity powders is desirable because high purity powders prevent the formation of Fe2B and Mo2FeB2 phase which comsume the ductile binder phase.

• IMMUNE NETWORK
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• 제6권3호
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• pp.138-144
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• 2006

Background: There are at least two different subsets of B cells, B-1 and B-2. The characteristic features and function of B-2 cells in addition to the effect of steroids on B-2 cells are well-known. Although B-1 cells have different features and functions from B-2 cells, the effect of steroids on B-1 cells is not completely understood. Therefore, this study examined the effects of dexamethasone on peritoneal (or B-1 cells) and splenic B cells (or B-2 cells). Methods: Purified B cells were obtained from the peritoneal fluid and the spleens of mice. The isolated B cells were cultured in a medium and after adding different concentrations of dexamaethasone. The cell survival rate was measured by flow cytometry using propidium iodide. The expression level of the B cell surface marker was analyzed by flow cytometry. During the culture of these cells, immunoglobulin secreted into the culture supernatants was evaluated by an enzyme-linked immunosorbent assay. Results: The survival rate of peritoneal and splenic B cells decreased with increasing dexamethasone concentration. However, the rate of peritofieal B cell apoptosis was lower than that of splenic B cells. CDS and B7.1 expression in peritoneal B cells and CD23 and sIgM expression in splenic B cells after the dexamethasone treatment were reduced. When B cells were treated with dexamethasone, the spontaneous IgM secretion decreased with increasing dexamethasone concentration. Conclusion: Dexamethasone induces apoptosis in peritoneal and splenic B cells. However, peritoneal B cells are less sensitive to dexamethasone. The dexamethasone suppressed expression of the surface markers in peritoneal B cells is different from those in splenic B cells.

• Biomolecules & Therapeutics
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• 제18권4호
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• pp.463-468
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• 2010

T-cell activation depends on signals received by the T-cell receptor and CD28 co-stimulatory receptor. Since B7.1 and B7.2 molecules expressed on the surface of antigen presenting cells provide co-stimulatory signals through CD28 to T-cells, an inhibitor of CD28-B7.1/B7.2 binding has been proposed as a therapeutic agent for suppression of excessive T-cell activity. Although anti-B7.1/B7.2 antibodies are known to block B7.1 and B7.2 molecules, their effects on intracellular events in antigen presenting cells remain unclear. In this study, anti-B7.1/B7.2 antibodies decreased secretion of nitric oxide and pro-inflammatory cytokines such as TNF-$\alpha$, IL-$1{\beta}$, and IL-12 in LPS-activated RAW264.7 macrophage-like cells and peritoneal macrophages. Moreover, anti-B7.1/B7.2 antibodies inhibited $I{\kappa}B{\alpha}$ phosphorylation and down-regulated expression of co-stimulatory molecules including B7.1, B7.2, and PD-L1 in LPS-stimulated peritoneal macrophages. These findings suggest that CTLA4-Ig and anti-B7.1/B7.2 antibodies may be candidates to treat chronic inflammatory diseases and autoimmune responses caused by excessive activation of both T-cells and macrophages.

• 한국정보과학회:학술대회논문집
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• 한국정보과학회 2004년도 가을 학술발표논문집 Vol.31 No.2 (1)
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• pp.391-393
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• 2004

네트워크의 발전과 함께 인터넷을 통한 기업 활동이 점차로 증가하면서 기업들간(B2B)에 실시간 데이터를 안전하게 서비스하기 위하여 여러 개의 시스템이 거미줄처럼 연계되고 있다. 전통적으로 기업들간에는 EOI(Electronic Data Interchange) 시스템과 독자적인 부가가치 통신(VAN, Value-Added Network)을 통한 데이터 교환방식을 사용했으나, 이 모델은 초기비용이 비쌀 뿐만 아니라, 데이터를 실시간 이벤트가 아닌 일괄작업(batch)으로 처리하였다. 그러나, 현재 B2B 간의 데이터 교환 및 상호 작용 방법으로 인터넷, XML, 그리고 메시징 시스템을 사용하고 있으며 특히, 메시징 시스템은 소규모의 시스템이 B2B에 참여하거나 탈퇴하는 비즈니스 작업의 어려움을 덜어준다. 본 논문에서는 인터넷상에서 이루어지는 B2B간의 데이터 교환 및 상호 작용을 위하여 메시징 시스템중 대표적인 JMS를 기반으로 안전한 데이터 교환 모델을 설계 및 구현한다. 따라서, 본 논문에서 제시하는 메시징 모델을 B2B 시스템에 적용하면 기업들간 안전한 메시지 전송을 보장할 수 있다.

• 한국식품영양과학회지
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• 제24권4호
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• pp.487-492
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• 1995

The purpose of this study was to investigate the effect of vitamin B2 deficiency on fuel metabolism in streptozotocin-induced diabetic rats. Thirty rats were fed a vitamin B2 deticient diet(-B2) or a control diet (＋B2) for 2 weeks and then subdivided into 3 groups respectively : base group, one day diabetic group and three day diabetic group. Diabetes of the rats were induced by streptozotocin injection into the tail vein. Glucose, glycogen, protein, alanine, triglyceride and free fatty acid were compared in plasma, liver, skeletal muscle of rats. Also, the total urinary nitrogen and glucose excertion were compared. Compared with ＋B2 rats, the increase of plasm glucose in -B2 rats due to the diabetes tended to be smaller. After diabetes were induced, the levels of plasma protein and alanine was significantly decreased and the urinary nitrogen excretion was significantly increased in -B2 rats. The level of plasma free fatty acid was increased continuously in B2 rats while increased at the first day and decreased at the third day diabetes was induced in ＋B2 rats. These results suggest that vitamin B2 deficiency increase protein catabolism due to the decrease of fatty acid oxidation. Thus, vitamin B2 deficiency in diabetes impair the adaptation of animals to the fuel metabolism and aggravate the body protein wasting which is one of the chronic complications of diabetes.

• 한국IT서비스학회지
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• 제14권4호
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• pp.185-197
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• 2015

As the uncertainty of demand in B2B electronics market has increased, firms need a strong method to estimate the market demand. An accurate prediction on the market demand is crucial for a firm not to overproduce or underproduce its goods, which would influence the performance of the firm. However, it is complicated to estimate the demand in a B2B market, particularly for the private sector, because firms are very diverse in terms of size, industry, and types of business. This study proposes both qualitative and quantitative demand forecasting approaches for B2B PC products. Four different measures for predicting PC products in B2B market with consideration of the different PC uses-personal work, common work, promotion, and welfare-are developed as the qualitative model's input variables. These measures are verified by survey data collected from experts in 139 firms, and can be applied when individual firms estimate the demand of PC goods in a B2B market. As the quantitative approach, the multiple regression model is proposed and it includes variables of region, type of industry, and size of the firm. The regression model can be applied when the aggregated demand for overall domestic PC market needs to be estimated.

• 한국산학기술학회논문지
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• 제2권1호
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• pp.67-78
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• 2001

본 연구는 현재의 B2C 중심의 e-비즈니스 환경에서 B2B로의 활성화를 위한 방안으로 ERP의 도입을 제시하고 있다. 최신 경영정보기술로서 ERP는 B2B의 문제점들을 해결할 수 있는 수단으로서 작용할 수 있다. 따라서 본 연구는 ERP의 특징에 관한 논의를 B2B 실행상의 문제점 해결 가능성에 초점을 두어 다루었다. 또한 ERP가 기업간 e-비즈니스에 적용되었을 때 어떠한 가치를 창출하고 어떠한 효익을 제공할 수 있는지를 파악하였다. 마지막으로는 ERP 도입을 통한 e-비즈니스의 가치창출이 예견된다면 기업의 입장에서 ERP도입 방안과 정부의 입장에서 어떠한 제도적 지원이 있어야 하는지를 논의하였다.

• 디지털융복합연구
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• 제10권8호
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• pp.81-90
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• 2012

본 연구의 목적은 B2C(Business-to-Customer) 소비재 시장에서 사용하는 마케팅 커뮤니케이션을 B2B(Business-to-Business) 산업재 시장에 적용하여 마케팅 커뮤니케이션이 신뢰에, 신뢰가 장기지향성에 미치는 영향을 확인함으로 장기적인 거래관계를 위한 마케팅 전략 수립에 도움이 되는 요인들을 확인하는데 있다. 이를 위하여, 공구유통업에 종사하는 도 소매상 177명을 대상으로 설문조사를 실시하였다. 실증분석 결과, 도 소매상들이 공급업체에 대해 느끼는 신뢰의 정도는 장기지향성에 상당히 긍정적인 영향을 미쳤으며, 마케팅 커뮤니케이션 요인들 중, 광고가 신뢰를 높이는 데에 도움이 된다는 것을 확인하였다. 따라서, B2B에서도 장기적 거래를 지향하기 위해서는, 신뢰를 높여야 하며, 광고와 같이 신뢰를 높일 수 있는 마케팅 커뮤니케이션 요인들을 개발하는 노력이 필요하다고 할 수 있다.

• 한국결정학회:학술대회논문집
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• 한국결정학회 2002년도 정기총회 및 추계학술연구발표회
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• pp.27-27
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• 2002

[Cp＊Rh(H₂O)₃](OTf)₂ (1) reacts with a stoichiometric amount of A and B [ A = Me₃SiN₃, B = 4,4'-bipridyl, (2a), A = Me₃SiNCO, B = 4,4'-bipridyl (2b)] in acetone at room temperature for 3 h to give the supramolecular complexes [Cp＊₄Rh₄(μ-A)₄(μ-B)₂] [A = Me₃SiN₃, B = 4,4'-bipridyl, (2a), A = Me₃SiNCO, B = 4,4'-bipridyl (2b)]. Complexes 2a and 2b have been structurally characterized by X-ray diffraction.