• The Journal of Korean Institute of Communications and Information Sciences
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• v.16 no.8
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• pp.719-731
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• 1991

This paper introduces a relatively simple computer simulation method for analyzing trajectory of electron beam in cylindrical electrode of the CRT, which outputs the cutoff voltag, beam current, spot size and plots out the trajectory, rom the input data on physical construction and applied voltages of electron gun. In order to improve computing speed in obtaining potential distibution, the authors have ivided the space into seveal setos and allocated different mesh sizes epending on the acuracy required to each sector and applied the finite difference method in calculation. The plot of trajectoy obtained from the simulation provided useful insight into the focusing mechanism of the CRT. The computed and measured result including beam curent. spot sizs and cutoff voltages for several model guns have ageed within eperimental error. The simulation program enables the designer to compare the effects of varied electrode shpe without the epense of building an actual gun and may be appli in esigning and implementing the electron gun assemply.

• Applied Biological Chemistry
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• v.17 no.2
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• pp.143-148
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• 1974

The interaction of the carcinogenic mycotoxin, Aflatoxin $B_1$, with the electron-donating molecule, benzene, was studied spectrophotometrically. The formation of charge-transfer complex between Aflatoxin $B_1$ and benzene in the presence of zinc chloride was observed and the apparent equilibrium constant of this charge-transfer complex was found to be 0.198 (liter $mole^{-1}$). It is assumed that, as the result of this study, some charge-transfer complexes could be formed between the weak electron-accepting Aflatoxin $B_1$ and strong electron-donating molecules, and the spectral changes occurred in the binding of Aflatoxin $B_1$ with proteins or DNA is attributed to the existence of charge-transfer type interaction.

• Journal of Internet Computing and Services
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• v.14 no.3
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• pp.1-13
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• 2013

The recent emergence of diverse platform-based media devices such as smart phones and iPads has aroused interest of consumers all across the world. This interest has led to digitalization of paper books and a steep growth in the digital publishing industry at home and abroad. However, advent of various devices and content has caused the issue of compatibility and produced needs and demand for standardization to exchange and share content related to digital publication. Through collection of opinions of 16 stakeholders from the industrial, academic, research, and public sectors, this study aims to examine predictable future changes about content and its distribution, devices, standardization, technical protective measures, and obstacles in future digital publishing and eventually to draw out areas and elements for future standards development.

• The Korean Journal of Zoology
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• v.33 no.1
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• pp.22-27
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• 1990

The gastro-endocrine cells were examined in the fundic region of stomach of the frog, Rana rugosa, by transmission electron microscope. In the present paper, at least three kinds of cell type distributed in this region were idendfted according to their morphological charactedstics based on the size, shape and electron density of the secretory granules. Type I cells were characterized by the presence of round or oval granules (300-5OOnm in diameter) with high electron density. The granules showed a wide lucent between the contents and the limiting membrane. This cell was reminiscent of the ECL cell in the human alimentary mucosa. Type II cells were characterized by the presence of spherical or oval granules (11O-230nm in diameter) with low or high electron density. The granules showed a clear halo between the homogenous contents and the limiting membrane. This cell was reminiscent of the G cell in the human alimentary mucosa. Type Ill cells were characterized by the presence of elongated oval or pheomorphic granules (50-2OOnm in diameter) with low or moderate electron density and abundant microfilament bundles in the cytoplasm. The granules contained a very thin halo.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.3
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• pp.433-437
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• 2005

Electron beam irradiation was applied to examine the microbial safety and qualities of sliced dried squid. Sliced dried squid was irradiated at dose of 2, 4, 8, 12, and 16 kGy. Microorganisms contaminated in sliced dried squid were significantly decreased by irradiation. Decimal reduction dose (D/sub 10/ value) of total bacteria count, yeast and mold, coliforms in sliced dried squid were 8.57, 4.60, and 8.10 kGy, respectively. Electron beam irradiation caused negligible changes in Hunter color L, a, and b value. Sensory evaluations of irradiated sliced dried squid showed that there were no significant changes among the samples. These results indicate that electron beam irradiation improves the microbial safety and qualities of sliced dried squid.

• Korean Journal of Food Science and Technology
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• v.37 no.2
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• pp.308-311
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• 2005

Electron beam irradiation was applied to examine microbial safety and qualities of black pepper powder and commercial Sunsik. Whole black pepper powder and commercial Sunsik were irradiated at 2, 4, 8, 12, and 16 kGy. Microorganism contamination in black pepper powder and commercial Sunsik were significantly decreased by irradiation. Decimal reduction doses ($D_{10}\;value$) of total bacteria count in black pepper powder and commercial Sunsik were 5.32 and 1.56 kGy, respectively. $D_{10}\;value$ of yeast and mold were 2.54 and 2.14 kGy for black pepper powder and commercial Sunsik, respectively. Electron beam irradiation caused negligible changes in Hunter color L, a, and b values. Sensory evaluations of black pepper powder and commercial Sunsik showed no significant changes among samples. These results indicate electron beam irradiation improves microbial safety and qualities of black pepper powder and commercial Sunsik.

• The Korean Journal of Archival Studies
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• no.18
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• pp.179-220
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• 2008

Under the physical records management system, both the records and users could be controlled and secured by closing the door of Archives or using permitted records which is used only approved users. According to the electronic records management system and the concept of service on the basis of users, we have to give up the classical manner. As an alternative, we have to consider the electronic access control system. To accomplish this purpose, functional requirements of ERMS that is issued by UK, EU, U.S and Australia must be compared and analyzed. On the basis of U.K ERMS which is more detailed, 'common access control functional requirements' are arranged. As the access control functional requirements is applied in the records classification scheme, we could find out how the access control is executed in ERMS.

• Applied Microscopy
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• v.32 no.1
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• pp.67-80
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• 2002

This study was carried out to investigate the effects of deer antler extract on the regeneration of peripheral nerves. Sprague-Dawley male rats weighing about 300 gm were fed deer antler extract for 1, 2, and 3 weeks per oral (1.5 ml/100 gm B.W.), respectively, once a day and transected both sides of sciatic nerve of each leg. After keeping for 6 hours, sciatic nerves taken from proximal part of transected region were treated with conventional transmission electron microscopical method and then observed with electron microscope. The results obtained were summarized as follows; 1. Sciatic nerves of normal control group were not showing any sprouts and electron dense axolemmal projections were frequently observed. 2. Sciatic nerves of saline treated groups were showing axonal sprouts at the nodes of Ranvier. The length of them was usually short, and numerous vesicles, vacuoles and organelles including neurofilament were contained. The number of nodes of Ranvier containing sprouts from 100 longitudinal sectioned nerve fibers was 29 (29%) in 1 week treated group, 32 (32%) in 2 weeks treated group, and 30 (30%) in 3 weeks treated group, respectively. 3. Sciatic nerves of deer antler treated groups were showing axonal sprouts at the node of Ranvier as well. Although most of the sprouts were short, some sprouts of 2 weeks and 3 weeks treated groups were quite long. Sprouts usually contained numerous vesicles, vacuoles and cell organelles such as neurofilaments and mitochondria. The number of nodes of Ranvier containing sprouts from 100 longitudinal sectioned nerve fibers was 38 (38%) in 1 week treated group, 46 (46%) in 2 weeks treated group, and 48 (48%) in 3 weeks treated group respectively. The results described above explain pretreatment of deer antler extract improves the sprout formation of transected sciatic nerves, and then it suggests deer antler may be effective for the regeneration of peripheral nerves.

• Applied Microscopy
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• v.37 no.2
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• pp.83-91
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• 2007

The present study examined the epidermal changes of adhesive disks which occur during attachment in Parthenocissus tricuspidata using scanning and transmission electron microscopy. Several adhesive disks, each covered with a bract, develop from the shoot apical meristem during early development. In the initial stage, the adhesive disks are club-shaped and their upper and lower epidermis are indistinguishable. However, in the actively growing stage, they become spherical and both epidermis are clearly differentiated into the adventitious roots. Prior to wall attachment, the adhesive disks exhibit adaxial convex and abaxial concave shapes, and electron-dense substances are abundant in the vacuoles of epidermal cells. The peripheral area of the adhesive disk is adhered first to the wall surface, while the central area is drawn inward in a vacuum-like state during attachment. As the attachment progresses and the electron-dense substances continue to discharge, the upper and lower epidermis rapidly undergo deterioration and the disks shrink considerably. At this stage, structural changes of the lower epidermis occur much faster than in the upper one. The discharged substance is accumulated on the wall surface, and this aids the attachment of adhesive disks on the wall for long periods. In this manner, the shape and structure of the adhesive disk epidermis change drastically from initial growth to the mature stage. Further, the role of electron-dense substance and shrinkage of the disk during attachment has been discussed in Parthenocissus tricuspidata.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2004.06a
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• pp.353-354
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• 2004

사용후 핵연료의 조성을 분석하거나 또는 반사전자상과 2차 전자상 등으로 시료를 관찰하기 위해서는 핫셀(Hot cell)에 증착기(coater)를 설치하여 시료표면을 전도성 물질인 탄소 등으로 증착시켜야 한다. 그러나 원격조정기를(manipulator)를 이용하여 수행되는 핫셀에서의 증착작업은 사용후 핵연료 시험의 선진분석기술을 갖고 있는 원자력 선진국에서도 핫셀내에 설치되어 있는 증착기의 탄소봉을 교체하는 작업과 진공장치의 성능 유지가 까다로워 시료표면에 균질하게 전도성 물질을 증착시키는 작업에 많은 어려움을 겪고 있다. 본 연구는 통상적으로 이용되는 증착기를 사용하지 않고 Silver Paint를 사용하여 사용후 핵연료를 분석할 수 있는 새로운 방법에 대한 연구를 수행하였다. 산화물 핵연료는 전기전도도가 매우 낮아($3{\times}10^{-1}~4{\times}10^{-8}/ohm{\cdot}cm$)입사된 전자의 이동이 원활하지 못해 일어나는 들뜸(Charging)현상이 발생한다. 그러나 Silver Paint 에 사용후 핵연료를 접착하면 모세관(capillary)현상에 의해 시료 주위와 핵연료의 결정립계로 Silver가 스며들어 입사된 전자의 이동이 원활해져 전도성이 극히 낮은 시료의 분석이 가능하게 된다. 본 시험에 사용된 EPMA는 (Electron Probe Micro Analyzer, SX-50R, CAMECA, Paris, France) 고 방사능을 띤 조사 핵연료의 시험을 수행할 수 있도록 기기의 적절한 부위에 납과 텅스텐으로 차폐되어 시편의 방사능 세기가 $3{\times}10^{10}Bq$까지 시험 가능한 기기이다. 그림 1은 JAERI 에 설치 운영중인 증착기 설비 사진이다. 그림에서 핫셀에 설치된 증착기의 진공을 유지하기 위해 핫셀 벽을 관통하여 증착기 본체까지 연결된 배출관의 형상과 복잡한 주변장치들을 볼 수 있다. 그림 2는 비조사 핵연료 시편을 Silver Pain떼 접착한 사진이다. 그림은 시료주위와 시료 표면까지 Silver Paint가 도포된 모습을 보여주고 있다. 상용발전소에서 연소도가 50,000 Mwd/tU인 사용후 핵연료를 상기와 같은 방법으로 만든 시편의 표면을 관찰한 사진을 그림 3~8에 나타내었다. 그림 3은 핵연료 중앙부위의 결정립을 나타낸 그림이다. Silver Paint만으로 접착한 시료의 표면관찰 및 정량분석이 그림에서 보듯이 가능함을 확인하였다. 그림 4는 사용후 핵연료시료를 중앙부위에서 가장자리까지를 다섯 부위로 나누어 그 중 중앙부위(1/5) 지점의 입계 및 형상을 관찰한 사진이다. 결정립의 크기가 다른 부위보다 상대적으로 크고, 결정립에 생성된 기공이 발달되어 있음을 볼 수 있다. 그림 5와 6과 7은 중심부위와 rim부위 사이 지점을 관찰한 사진으로서 결정립과 기공의 분포가 비슷한 형상을 나타내고 있음을 관찰할 수 있었다. 그림 8은 rim 부위 사진으로 전형적인 rim 영역 현상을 관찰할 수 있었다. 표 1은 그림 2와 같이 비조사 산화물 핵연료를 Silver Paint로 접착한 시편을 정량 분석한 결과이다. 시편의 조성은 33.6 at% U, 66.4 at% O의 결과를 얻었다. 산화물 핵연료의 표면 관찰 및 정량 분석 시험시 시편 표면을 전도성 물질로 증착시키지 않고, Silver Paint 에 시편을 접착하는 방법으로도 만족한 시험 결과를 얻을 수 있었다.