• Development and Reproduction
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• v.7 no.2
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• pp.81-88
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• 2003

Initiation and activation of sperm motility are prerequisite processes for the contact and fusion of male and female gametes at fertilization. The phenomena are under the regulation of CAMP and $Ca^{2+}$ in vertebrates and invertebrates. Mammalian sperm requires $Ca^{2+}$and cyclic AMP for the activation of sperm motility. Cell signaling for the initiation and activation of sperm motility has been well studied in the ascidians, Ciona intestinalis and C. savignyi and salmonid fishes. In Ciona, whose cell signaling for activation of sperm motility has been established, the sperm-activating and -attracting factor released from unfertilized egg requires extracellular $Ca^{2+}$ for activating sperm motility and eliciting chemotactic behavior of the activated sperm toward the egg. On the other hand, the cyclic AMP-dependent phosphorylation of protein is essential for the initiation of sperm motility in salmonid fishes. A decrease in the environmental Ti concentration surrounding the spawned sperm causes a li efflux and $Ca^{2+}$ influx through the specific $K^{+}$ channel and dihydropyridine-sensitive L-/T- type $Ca^{2+}$ channel, respectively, thereby leading to the membrane hyperpolarization and $Ca^{2+}$ influx. The membrane hyperpolarization synthesizes cyclic AMP, which triggers the luther Process of cell signaling, i.e., cyclic AMP-dependent protein phosphorylation, to initiate sperm motility in salmond fishes.almond fishes.

• Smart Media Journal
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• v.5 no.4
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• pp.103-110
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• 2016

This study aims to establish the standards to give the design weight in case when developing equipment designs, by classifying products with similar purposes in accordance with the morphological characteristics and also extracting the typicality. Limiting the sampling group for the extraction of the typicality to a pendant-type and a ceiling buried-type through the preceding case study and consultation with experts, the survey was conducted for majors and relevant workers in six cities, sampling products released in Korea and Japan before May 2016. The 1st survey was about the Morphological classification, and the 2nd times about the extraction of the typicality while the 3rd one was about the classification of the morphological attributes. By drawing the design attributes based on the functional/morphological classification and formative principles, it aimed to establish the base of the future research on the measurement of design weight. The results of this study aim to efficiently establish the roles of design technology in accordance with changes in the lighting fixture market caused by the substitution of light sources, and also to draw the development direction to rapidly cope with the accelerated changes in lighting design types and corporate R&D.

• The Journal of Korean Society for Radiation Therapy
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• v.20 no.2
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• pp.123-130
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• 2008

Purpose: To provide practical education, most universities should be equipped with medical appliances in need. As compensatory measures, Gimcheon College has produced in-house dummy linac and dummy accessories, we are going to report efficiency and its usage. Materials and Methods: Dummy linear accelerator (DLINAC-001) has the same mechanical functions as rotation of gantry and collimation in linear accelerator. In addition, to maximize practical education, we have produced and utilized in-house custom blocks, wedge filters, electron cones and head rests. Results: The in-house produced linear accelerator with the same mechanical functions as the linear accelerator, DLINAC-001 can be effectively used in practicing diverse medical instruments. Conclusion: We have produced dummy linear accelerators and dummy accessories and utilized them in practice classes, which can provide the students with clinical training in diverse fields. Consequently, the students exposed to the maximized educational effectiveness can be easily equipped with the practical competence required in real clinical fields.

• Journal of the Korean Society of Radiology
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• v.6 no.6
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• pp.465-471
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• 2012

In this study, three dimensional X-ray dose distribution from dental X-ray generator system was measured by ALOKA PDM-117 dosimeter. The X-ray dose distribution will be change with XCP-DS FIT in oral shot, because the distance between X-ray generator and the dosimeter. The X-ray dose change affects on patient exposure and radiograph image quality. Therefore, it is important to obtain relation between the X-ray dose and the distance. The X-ray dose at the central position was decreased with increasing the distance. Furthermore, the dose at the edge of the X-ray flux was increased with increasing the distance. The increased dose affects on the patient radiation exposure. The present results will provide for good dental radiograph image and reducing radiation over-exposure on patient.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.63-63
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• 2011

비정질 반도체/절연체의 직류와 교류 전도도 스펙트럼은 주파수에 대한 거듭제곱의 법칙 (power-law)을 따르는 보편성이 있음이 확인되었다. 이러한 보편성은 다양한 비정질 반도체/절연체 물질에서 공통적으로 관찰되었으며 현재까지 이 보편성의 물리학적 원인이 정확히 규명되지 않고 있다. 이 보편성을 설명하기 위한 모델로서 비정질 반도체/절연체 내의 전자/정공의 호핑 전도기구 (hopping conduction mechanism)가 제시된 바 있으며 다양한 비정질 시스템의 전도도 스펙트럼 해석에 인용되고 있다. 그러나 직.교류 전도기구 사이의 상이함에 대한 이견이 있으며 현재까지 정확히 규명된 바 없다. 본 연구에서는 비정질 GeSe 반도성 물질의 전도도 스펙트럼을 10 Hz-1 MHz 주파수 대역에서 측정하였으며 이를 위해 백금 상.하부 전극을 갖는 크로스바(crossbar)형의 금속-절연체-금속구조의 2단자 소자를 제작하였다. 측정 스펙트럼으로부터 본 연구의 GeSe 물질이 앞서 언급한 비정질 물질의 보편성에 부합함을 확인하였으며 스펙트럼 내의 직류와 교류 성분을 명확히 분리할 수 있었다. 직.교류 전도도 스펙트럼의 명확한 기구 분리를 위하여 4개의 상이한 면적을 갖는 크로스바에 대한 측정을 실시하였으며 그 결과로 직.교류 전도도의 상이한 면적 의존성을 관찰하였고 이를 근거로 직.교류 전도도가 서로 다른 전도기구에 기인함을 간접적으로 알 수 있었다. GeSe의 전도도 스펙트럼의 온도 의존성 실험을 위해 시편의 온도를 20-300 K 범위에서 변화시키며 전도도 스펙트럼을 측정하였으며 이를 통해 교류 전도도 스펙트럼 내에 상이한 두 개의 전도 기구가 혼재해있음을 규명하였다.

• Journal of Food Hygiene and Safety
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• v.22 no.1
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• pp.52-56
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• 2007

In order to offer monitoring data about standard and specification of metallic kitchenware, we carried out the material test and migration test of lead and antimony in 71 kinds of kitchenwares. As a result of this study, Pb was detected less than 0.06% at the material test and Sb was not defected in 71 kinds of kitchenwares. Pb was also detected less than 0.41 mg/L at the migration test. Currently according to the Food Code of Korea, Pb and Sb in metal product shall not exceed 10% and 5%, respectively and Pb migrated from metal product shall not exceed 1.0 mg/L. Therefore, our all data are not exceeding the standard and specification of metal product and show that all the kitchenwares in domestic circulation may be safe.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.13 no.10
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• pp.1040-1047
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• 2002

In this paper, we investigated noise decoupling on the power bus by the screw connection, used to the mechanical join and grounding of the PCB ground to chassis. The screw connection penetrates the power bus and then it affects noise propagation on the power bus. To verify effect of the screw connection, we compare bare board with board having screws connection with 0.5 mm separation between power bus and chassis. From these results, we observed that the power bus noise was decreased about 5 dB at the frequency range from 0.1 GHz to 1 GHz. Also, we verified that a 4-layer PCB with signal trace had the better signal quality up to 600 MHz by the screw connection. Therefore, these results will be useful in designing to the high speed circuit and chassis.

• Journal of the Korea Society of Computer and Information
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• v.13 no.4
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• pp.263-271
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• 2008

This study is about the criminal information system of police cooperation organization between European nations. The criminal information system of police cooperation organization between European nations is the organization created by the sign of the Europol convention in 26 July 1995 and the effectuation in 1 October 1998 for European nations' cooperative confrontation with frequent international terror, international organization crime, drug trafficking, illegal immigrant smuggling, and other critical crimes. From the beginning, this organization established the criminal information system for overcoming the working limits of previous international police organization. This system consists of information system, work file, and index system and enables every national unit or other law enforcement agents to collect, exchange, and utilize the information. Additionally, it try to keep in step with the rapidly change time, such as the integration with CMS, the establishment of correspondence system against cyber crime, and the introduction of biometric database. The criminal information system of the Europol gives important suggestions to the police cooperation organization between nations, besides prevention and suppression against the international crimes in Europe.

• Journal of rehabilitation welfare engineering & assistive technology
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• v.8 no.3
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• pp.221-226
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• 2014

The purpose of this study is to suggest improvement directions and analysis of assistive technology service linkage on public benefits in local assistive technology center. The service steps and the main program parts of public benefits linkage in local assistive technology center was identified, and the present status of associated repair works and contact suppliers of assistive technology device in local community was investigated. The result showed the most common level of associated status to provide information of assistive technology devices in public benefits. All the centers provided repair service, and it was typically performed to light maintenance. The centers offered with associated professional repair service supplier for high maintenance service. The connection with assistive technology device supplier appeared a lot of regional difference. Henceforth, the centers will be required to distribute more various assistive technology devices, it is necessary upgrading the quality of information and interaction with the public benefits supporting organizations through its expansion, and it is need to ensure based on policy through the analysis of the effectiveness about linkage.

• 연구논문집
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• s.30
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• pp.101-110
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• 2000

Weft insertion mechanism is for completing the structure of yarn and weft yarn and its driving method is screw type. In the high speed rapier loom, weft yarn is thrown by insert rapier and carrier rapier into the shed which make divide two parts of upper part ant lower part for warp yarn. It is possible for this mechannism to reduce the size of rapier and wheel, and directly connected to the main shaft without gear belt. Therefore, exact rapier motion through realization of arbitrary acceleration diagram requested rapier and optimal design for high speedization and operating rate increasing are necessary. In this study, with a view to exact system analysis for understanding of overall trace and high speedization of rapier loom through computer simulation. we report not only deduction of displacement, velocity, and acceleration components of rapier for analysis theory establishment, of weft insertion mechanism and exact motion induction according to screw rotation, but also development of simulation program for realization these on the monitor.