• Bulletin of the Korean Chemical Society
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• 제22권4호
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• pp.375-378
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• 2001

The palladium catalyzed dehalogenative homocoupling of haloarylsulfonates under reductive conditions has proceeded selectively depending on the type of the halogen. Thus, an iodo or a bromo leaving group of haloarylsulfonates was homocoupled to gi ve symmetrical biaryls in good yields with the sulfonate group intact, whereas a chloro leaving group gave no reaction under the conditions used. When the more reactive nickel catalyst was employed instead of the palladium catalyst in the reaction, both dehalogenative and desulfonative homocouplings of haloarylsulfonates occurred regardless of the type of the halogen used.

• 전자공학회논문지
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• 제52권12호
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• pp.55-63
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• 2015

최근 무선통신 장비를 이용하여 원격으로 폭발시킬 수 있는 무선 급조폭발물 (RCIED)에 의한 테러의 위협이 전 세계적으로 증가하고 있다. 이에 대응하기 위해 급조폭발물을 기폭 시키는 무선 트리거 신호를 정상적으로 수신하지 못하게 하는 재밍 기법이 사용되고 있다. 기존의 재밍 기법으로는 전 대역에 항상 재밍 신호를 방출하는 상시 광대역 재밍(active barrage jamming) 기법이 주로 사용되고 있으나, 전력 소모가 매우 커서 주요 운송 수단인 차량 탑재용으로 사용하기에는 운용시간이 너무 짧다는 단점이 있다. 이러한 기존 기법의 단점을 극복하기 위하여 최근에 반응 재밍(reactive jamming) 기법이 관심을 받고 있다. 반응 재밍은 폭발 트리거 신호를 감지하여 신호가 존재하는 대역을 선별적으로 대응하는 재밍 기법으로서, 기존 재밍기법에 비해 전력 효율이 높기 때문에 차량 탑재용으로도 운용 시간을 대폭 늘릴 수 있다. 하지만, 반응 재밍은 폭발 트리거 신호를 포착한 뒤 재밍 신호를 방사하기 때문에, 폭발 트리거 신호 환경에 대한 정보를 바탕으로 반응 재밍이 이루어져야 하는 반응시간에 대한 기준이 필요하다. 이를 위해서 본 논문에서는 반응 재밍을 활용할 수 있는 이동통신 환경에 대해서 필요한 반응시간을 이동통신 시스템에서의 호 처리시간(call processing time) 정보를 바탕으로 도출하고, 반응 재밍에서 사용될 수 있는 repeater 재밍에 대해 시뮬레이션을 통해 성능 분석을 수행한다.

• IMMUNE NETWORK
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• 제2권4호
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• pp.189-194
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• 2002

Although the exact mechanism responsible for the pathogenesis of psoriasis is unclear, interferon-${\gamma}$ producing type 1 T cells have been reported to play a significant role. Infiltrating activated type 1 T cells in the lesions are believed to be responsible for stimulating keratinocytes, which produce many cytokines and growth factors. The hyperproliferative epidermis is understood to be the result of either the cytokines produced by the intraepidermal T cells or the reactive phenomenon after keratinocyte damage. The microenvironment in psoriatic lesions deviates toward the type 1 status, because of the increased type 1 cytokines and either the decreased or unchanged type 2 cytokines observed in psoriatic lesions. Therefore, this review focused on a T-cell-mediated immunological basis for the current hypothesis of the psoriasis pathogenesis.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2009년도 추계학술대회 논문집
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• pp.330-331
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• 2009

• 한국진공학회:학술대회논문집
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• 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
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• pp.230.2-230.2
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• 2016

A new approach for antimicrobial is based on the overproduction of reactive nitrogen species (RNS), especially; nitric oxide (NO) and peroxinitrite ($ONOO^-$-) are important factors to deactivate the bacteria. Recently, non-thermal atmospheric pressure plasma jet (APPJ) has been frequently used in the field of microbial sterilization through the generation of different kinds of RNS/ROS species. However, in previous study we showed APPJ has combine effects ROS/RNS on bacterial sterilization. It is not still clear whether this bacterial killing effect has been done through ROS or RNS. We need to further investigate separate effect of ROS and RNS on bacterial sterilization. Hence, in this work, we have enhanced NO production, especially; by applying a 1% of HNO3 vapour to the N2 based APPJ. In comparison with nitrogen plasma with inclusion of water vapour plasma, it has been shown that nitrogen plasma with inclusion of 1% of HNO3 vapour has higher efficiency in killing the E. coli and different type of cancer cell through the high production of NO. We also investigate the enhancement of NO species both in atmosphere by emission spectrum and inside the solution by ultraviolet absorption spectroscopy. Moreover, qPCR analysis of oxidative stress mRNA shows higher gene expression. It is noted that 1% of HNO3 vapour plasma generates high amount of NO for killing bacteria and cancer cell killing.

• 대한한방소아과학회지
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• 제8권1호
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• pp.39-58
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• 1994

Even though appropriate immune response is necessary for the survival of the individual, excessive or insufficient immune response might cause autoimmune or allergic disease respectively. So the immune response must be controlled to the degree that is beneficial for the well being of the individual. This study was undertaken to know the effects of Junsibaekchulsan(JB) on the immune system od the mouse. For the evalulation of the cell-mediated immunity(CMI), delayed-type hypersensitivity against dinitrofluorobenzene(DNFB) were measured, and humoral immunity, hemagglutinin and hemolysin titers against SRBCs(sheep red blood cells) were measured, and rosette formation of spleen cells with SRBCs were measured. For the evaluation of innate immunity, phagocytic activity of macrophages, natural killer cell activity, and reactive nitrogen and oxygen intermediates were measured. The results are as follows: 1. The administration of JB depressed the antibody formation (hemagglutinin and hemolysin) against SRBCs. 2. The administration of JB did not affect the delayed-type hypersensitivity against DNFB. 3. The administration of JB did not affect the cytotoxic activity of natural killer cells. 4. The administration of JB increased the phagocytic activity of macrophages. 5. The administration of JB increased the rosette formating cells of the spleen cells. 6. The exposure of JB induced the secretion of reactive nitrogen intermediates but administration of JB deperssed the production of reactive oxygen intermediates. Administration of JB selectively depressed the humoral immune response without affecting CMI and innate immunity. These results of JB on the immune system might be useful for the treatment of such.

• 대한수의학회지
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• 제24권1호
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• pp.8-16
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• 1984

The work was conducted with tole purpose of investigation on the development pattern of epididymis in accordance with the growth of meat-type cockerels. 1. Histological features of various ductules in epididymis of the cockerel on the age of weeks were as follow: within 10 weeks after hatching rete testis and connecting ductules were well developed but efferent ductules were observed in immature form. During 10th to 20th week, the lining epithelium of various ductules in epididymis was in the developing stage near to the mature form. From 21th week, various ductules were abruptly matured. Lumen of rete testis was lined by simple squamous or simple columnar epithelial cells and that of efferent ductules, having many folds and being larger than any others, were lined by ciliated pseudostratified columnar epithelium with ciliated columnar cells, clear cells and basal cells were noted. Luminal epithelium of connecting ductules was composed of ciliated low pseudostratified columnar epithelial cells, ciliated columnar cells, clear cells and basal cells. The luminal surface of epididymal ducts was pseudostratified columnar epithelium and which was composed of high columnar cells and basal cells. 2. In the India ink absorption test, India ink granules were noted above the nucleus of some cells in the efferent ductules and the connecting ductules at 7 hours after administration of India ink to the mature epididymis, but not absorbed in the other ductules. The granules reactive to acid phosphatase were most abundant in some epithelial cells of efferent ductules and connecting ductules, especially above the nucleus of cells. The granules reactive to alkaline phosphatase were noted on the luminal border of efferent ductules. The granules reactive to PAS were scattered in the epithelial cells of efferent ductules and connecting ductules.

• Childhood Kidney Diseases
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• 제12권2호
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• pp.133-142
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• 2008

이식을 위해서는 수여자와 공여자의 혈액형과 HLA type을 알아야 한다. 통상 ABO 혈액형이 적합한 경우 이식할 수 있으며 HLA 부적합은 근래 큰 문제가 되지 않으나 HLA 부적합이 없는 경우 이식장기의 장기생존률이 높다. PRA(panel reactive antibody)는 수여자가 HLA에 감작되었는지 검사하는 방법이며 이식 전에는 반드시 교차반응 검사를 하여 음성인 경우에만 이식을 진행한다. 이식 전후에 donor specific antibody(DSA)를 검사하여 이식장기에 대한 수여자의 면역반응을 예측 할 수 있다. 근래에는 스테로이드, calcineurin inhibitor(cyclosporine, tacrolimus), azathioprine 또는 mycophenolate mofetil (MMF)의 삼제요법을 주로 사용하며 항림프구 항체 (Thymoglobulin 또는 항IL-2 receptor 항체 basiliximab/daclizumab)을 이용하여 이식 초기에 면역억제상태를 induction하는 경우도 많다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회B
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• pp.2913-2917
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• 2007

Turbocharger has been widely used in many passenger cars in application with diesel engines because of high power and fuel efficiency. However, flow-induced noise (whoosh or hissing noise) which is generated within the compressor during its operation at marginal surge line can deteriorate noise characteristics. Hissing noise excitation was associated with the generation of turbulence within the turbocharger compressor and radiated through the transmission path in turbocharger system. In this study, a sharp-edged reactive-type muffler was devised and installed in the transmission path to reduce the hissing noise. Acoustic and fluid dynamic characteristics for the muffler were investigated which is related to the unsteadiness of turbulence and pressure in turbocharger system. A transfer matrix method was used to analyze the transmission loss of the muffler. Simple expansion muffler with extended tube of the reactive type is proposed for the reduction of high frequency component noise. Turbulence computation was carried out by a standard ${\kappa}-{\varepsilon}$ model. An optimal design condition of the muffler was obtained by extensive acoustic and fluid dynamic analysis on the engine dynamometer with anechoic chamber. A significant reduction of the hissing noise was achieved at the optimal design of the muffler as compared with the conventional turbocharger system.

• 한국정보통신설비학회:학술대회논문집
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• 한국정보통신설비학회 2003년도 하계학술대회
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• pp.286-288
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• 2003

In this paper, in order to obtain a large differential phase shift with a little change in applied voltage, a ferroelectric reflective load circuit has been designed on top of barium strontium titanate $(Ba,Sr)TiO_3$ [BST] thin film. The design of the ferroelectric reflection-type phase shifter is based on a reflection theory of terminating circuit, which has a reflection-type analogue phase shifter with two ports terminated in symmetric phase-controllable reflective networks. To achieve large amounts of phase shift in low bias-voltage range, the effects of change of capacitance and transmission line connected with two coupled ports of a 3-dB $90^{\circ}$ branch-line hybrid coupler have been investigated. A large phase shift with a small capacitance change in the parallel terminating circuit has been demonstrated in the paper.