레이저 위빙을 이용한 Al 6k21-T4 합금의 용접 강도 향상

김병훈,강남현,박용호,안영남,김철희,김정한,Kim, Byung-Hun,Kang, Nam-Hyun,Park, Yong-Ho,Ahn, Young-Nam,Kim, Cheol-Hee,Kim, Jung-Han 대한용접접합학회 2009 대한용접·접합학회지 Vol.27 No.4

For Al 6k21-T4 alloy, linear laser welding produced the lower shear-tensile strength than the base metal. This study improved the shear-tensile strength by using the weaving laser at the optimized welding condition, i.e., 2mm weaving width and 25Hz frequency. The large weaving width increased the weld width, therefore improving the joint strength. For the specimen of low strength, the porosity was distributed continuously along the intersection between the plates and fusion line. However, for the optimized welding condition, large oval-shaped porosities were located only in the advancing track of the concave part. Regardless of the welding condition, solidification cracking was initiated at the intersection and propagated through small porosities in the weld part. furthermore, the concave part had more significant porosity in the weld and HAZ, respectively than the convex part. The continuity of porosities played a key role to determine the strength. And, the weaving width was an important parameter to control the strength.

BAY11-7082에 의한 U937 세포의 CD29-매개성 세포간 유착과정 조절 효과

김병훈,조재열,Kim, Byung-Hun,Cho, Jae-Youl 대한약학회 2008 약학회지 Vol.52 No.5

BAY11-7082 was initially found to be an anti-inflammatory drug with NF-${\kappa}B$ inhibitory property. In this study, we evaluated modulatory function of BAY11-7082 on U937 cell-cell adhesion induced by CD29 (${\beta}1$-integrins). BAY11-7082 strongly blocked functional activation of CD29 (${\beta}1$-integrins), as assessed by cell-cell adhesion assay. However, this compound did not block a simple activation of CD29, as assessed by cell-fibronectin adhesion assay. In particular, to understand molecular mechanism of BAY11-7082-mediated inhibition, the regulatory roles of CD29-induced actin cytoskeleton rearrangement under cell-cell adhesion and surface level of CD29 were examined using confocal and flow cytometic analysis. Interestingly, this compound strongly suppressed the molecular association of actin cytoskeleton with CD29 at cell-cell adhesion site. Moreover, BAY11-7082 also diminished surface levels of CD29 as well as its-associated adhesion molecule CD147, but not other adhesion molecules such as CD18 and CD43. Therefore, our data suggest that BAY11-7082 may be involved in regulating immune responses managed by CD29-mediated cell-cell adhesion.

주기 및 비주기 태스크의 효율적인 관리를 위한 실시간 센서 노드 플랫폼의 설계

김병훈,정경훈,탁성우,Kim, Byoung-Hoon,Jung, Kyung-Hoon,Tak, Sung-Woo 한국정보처리학회 2007 정보처리학회논문지 C : 정보통신,정보보안 Vol.14 No.4

본 논문에서는 주기 및 비주기 태스크의 효율적인 관리를 제공하는 실시간 센서 노드 플랫폼을 설계하고 구현하였다. 기존 센서 노드의 소프트웨어 플랫폼은 제한된 센서 노드의 자원을 효율적으로 사용하기 위하여 메모리 및 전력 소비량의 최소화에만 초점을 두었기 때문에 태스크의 실시간성과 빠른 평균 응답시간을 보장하는 실시간 센서 노드의 소프트웨어 플랫폼에는 적합하지 않다. 이에 본 논문에서는 센서 노드의 소프트웨어 플랫폼으로 많이 사용되고 있는 TinyOS 기반에서 태스크의 실시간성과 빠른 평균 응답시간을 보장할 수 있는 기법과 한계를 분석하였으며, 모든 주기 태스크가 마감시한 내에 실행이 완료되는 것을 보장하고 비주기 태스크의 응답시간을 최소화하는 실시간 센서 노드 플랫폼을 제안하였다. 본 논문에서 제안한 플랫폼은 Atmel사의 초경량 8비트 마이크로프로세서인 Atmega128L이 탑재된 센서 보드에서 구현되었다. 구현된 실시간 센서 플랫폼의 성능을 분석한 결과, 모든 주기 태스크의 마감시한 보장을 제공함과 동시에 향상된 비주기 태스크의 평균 응답시간과 낮은 시스템의 평균 처리기 이용률을 확인할 수 있었다. In this paper, we propose a real-time sensor node platform that efficiently manages periodic and aperiodic tasks. Since existing sensor node platforms available in literature focus on minimizing the usage of memory and power consumptions, they are not capable of supporting the management of tasks that need their real-time execution and fast average response time. We first analyze how to structure periodic or aperiodic task decomposition in the TinyOS-based sensor node platform as regard to guaranteeing the deadlines of ail the periodic tasks and aiming to providing aperiodic tasks with average good response time. Then we present the application and efficiency of the proposed real-time sensor node platform in the sensor node equipped with a low-power 8-bit microcontroller, an IEEE802.15.4 compliant 2.4GHz RF transceiver, and several sensors. Extensive experiments show that our sensor node platform yields efficient performance in terms of three significant, objective goals: deadline miss ratio of periodic tasks, average response time of aperiodic tasks, and processor utilization of periodic and aperiodic tasks.

Long Photoperiod Affects Gonadal Development in Olive Flounder Paralichthys olivaceus

김병훈,이치훈,허상우,허성표,김대환,서해립,Sung Yeon Kim,이영돈 한국발생생물학회 2013 발생과 생식 Vol.17 No.3

To effects of sex maturation in olive flounder by regulating long photoperiod, gonadal development and GTH mRNA expression in the pituitary were investigated. Photoperiod was treated natural photoperiod and long photoperiod (15L:9D) conditions from September 2011 to March 2012. The results showed that natural photoperiodic group showed a higher gonadosomatic index (GSI) than long photoperiodic group during the spawning season (March 2012). The histological analysis of ovarian tissue showed that natural photoperiod group of ovaries contained vitellogenic oocytes, but long photoperiod group of ovaries mainly contained perinucleolus staged oocyte and oil-drop staged oocytes. The FSH mRNA of olive flounder, under natural photoperiod group, showed a significantly higher expression but no significant difference under long photoperiod group. The LHβ mRNA showed a significantly higher expression only under natural photoperiod group. These results may suggest that long photoperiodic information regulates secretion of pituitary FSH and LH and maintain early growing stage of gonadal development in this species.

CD29 및 CD98 활성 매개에 의한 Jurkat T 세포의 유착과 그 활용

김병훈,조재열,Kim, Byung-Hun,Cho, Jae-Youl 대한약학회 2009 약학회지 Vol.53 No.3

Cell-cell adhesion managed by various adhesion molecules plays an important role in regulating functional activation of cells. This event mediates attachment of inflammatory cells to endothelial cells, interaction of antigen-presenting cells with T cells and metastatic adherence of cancer cells to epithelial tissue cells. Therefore, this cellular response is considered as one of therapeutic target to treat various cancers and inflammatory diseases. To develop proper model for evaluation of functional activation of adhesion molecules, the ability of U937 and Jurkat T cells responsive to various adhesion inducers such as phorbal-12-myristate-13-acetate (PMA), staurosporin and monoclonal antibodies to CD29, CD43 and CD98 was investigated using quantitative cell-cell adhesion assay. U937 cells made more cell-cell clusters by the treatment of antibodies to CD29 and CD43 than Jurkat T cells, while Jurkat T cells exhibited increased cell-cell adhesion ability in CD98 antibody treatment. In agreement, the surface levels of CD29 and CD98 were highly observed in U937 and Jurkat T cells, respectively. Therefore, our data suggest that Jurkat T and U937 cells can be used for model system to evaluate functional activation of adhesion molecules such as CD29 and CD98.

Diethylstilbestrol의 단핵구의 세포간 유착과정 조절효과

김병훈,조재열,Kim, Byung-Hun,Cho, Jae-Youl 대한약학회 2008 약학회지 Vol.52 No.2

Diethylstilbestrol (DESB) is a synthetic estrogen not only that routinely prescribed, but also that known to be a teratogen. In this study, we found a novel pharmacological feature that DESB is able to positively modulate CD29 $({\beta}1-integrin)$ function. Thus, DESB up-regulated homotypic cell-cell adhesion of monocytic U937 cells mediated by CD29. However, DESB did not increase the surface level of CD29 and its binding activity to ligand (fibronectin), according to flow cytometric analysis and cell-fibronectin adhesion assay. Instead, the DESB-mediated up-regulation of cell-cell adhesion was blocked by several signaling enzyme inhibitors. Treatment of U0126 [an extracellular signal-regulated kinase (ERK) inhibitor], SB20358 (a p38 inhibitor) or Rp-8-pCPT-cGMP (a protein kinase G inhibitor) clearly inhibited DESB-mediated up-regulation of cell-cell adhesion induced by CD29. However, estrogen receptor antagonist ICI 182,780 failed to abrogate DESB effect. Therefore, our data suggest that DESB may up-regulate CD29-mediated cell-cell adhesion via modulating intracellular signaling enzymes such as ERK, PKG, and p38, independent of estrogen receptor function.

스트레스와 현대병-중년기의 건강

김병훈,Kim, Byeong-Hun 한국건강관리협회 1975 건강소식 Vol.3 No.5

활성화된 단핵구 및 대식세포의 항원제시기능에 대한 Kaempferitrin의 조절 효과

김병훈,조동하,조재열,Kim, Byung-Hun,Cho, Dong-Ha,Cho, Jae-Youl 대한약학회 2007 약학회지 Vol.51 No.6

Kaempferitrin, isolated from Kenaf (Hibiscus cannabinus), was examined to evaluate its modulatory effects on antigen-presenting cell functions of macrophages/monocytes such as phagocytosis of foreign materials, up-regulation of costimulatory molecules (CD40, CD80 and CD86), adhesion molecule activation, and antigen processing and presentation. Kaempferitrin strongly blocked up-regulation of CD40, CD80 and CD86, but not pattern recognition receptor (PRR) (e.g., TLR2). It also suppressed functional activation of CD29 (${\beta}1$-integrins), as assessed by cell-cell adhesion assay, required for T cell-antigen-presenting cell (APC) interaction. Furthermore, this compound did not block a simple activation of CD29, as assessed by cell-fibronectin adhesion assay. However, the compound did not diminish phagocytic uptake, an initial step for antigen processing, and ROS generation in RAW264.7 cells. In particular, to understand molecular mechanism of kaempferitrin-mediated inhibition, the regulatory role of LPS-induced signaling events was examined using immunoblotting analysis. Interestingly, this compound dose dependently suppressed the phosphorylation of $I{\kappa}B{\alpha}$, Src, Akt and Syk, demonstrating that it can negatively modulate the activation of these signaling enzymes. Therefore, our data suggested that kaempferitrin may be involved in regulating APC function-relevant immune responses of macrophages and monocytes by regulating intracellular signaling.

한국지역난방공사 화성지사 화학시험실 KOLAS 공인시험기관 인정

김병훈,Kim, Byeong-Hun 한국열병합발전협회 2009 열병합발전 Vol.71 No.-

단핵구 기능 수행에서의 $CD29({\beta}1-integrins)$ 조절 역할

김병훈,조재열,Kim, Byung-Hun,Cho, Jae-Youl 대한약학회 2008 약학회지 Vol.52 No.1

CD29 $({\beta}1-integrins)$ is one of major adhesion molecules involved in regulating cell adhesion, migration and morphological changes. In this study, we investigated the regulatory role of CD29 in monocytic functions using monocytic cell line U937 cells. CD29 was found to be one of highly expressed membrane proteins in U937 cells, according to flow cytometric analysis. The activation of CD29 by agonistic antibody MEM101A and extracellular matrix protein (ECM) fibronectin strongly induced cell-cell and cell-fibronectin adhesions. However, blocking antibodies to CD98 and CD147 showed different inhibitory features in these two adhesion events. Furthermore, U0126, an ERK inhibitor, only blocked cell-cell adhesion but not cell-fibronectin adhesion, indicating that cell-cell or cell-fibronectin adhesion events may be regulated by different molecular mechanisms. Meanwhile, CD29 activation also enhanced ROS generation but not phagocytic ability, and similarly radical scavenger N-acetyl-L-cysteine strongly blocked CD29-mediated cell-cell adhesion, implying that ROS may play a critical role in up-regulating cell-cell adhesion. Therefore, our data suggest that the activation of CD29 may be critically involved in regulating monocytic cell-mediated cell-cell adhesion and ROS generation.