• Journal of Photoscience
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• v.9 no.2
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• pp.236-239
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• 2002

Sunscreens have been advocated as an important means of preventing skin cancer. UV-induced immunosuppression is important for skin cancer development, yet the effectiveness of sunscreens in protecting the human immune system from UV radiation is unclear. The only currently accepted method of sunscreen rating is the Sun Protection Factor (SPF) based on prevention of erythema. We developed an in vivo non-invasive method for evaluating protection of the human immune system from UV radiation based on recall contact sensitivity to nickel, a common allergen. Using this system we showed that broad-spectrum sunscreens provide greater protection to the immune system than sunscreens which protect from UVB only. UVA was found to be immunosuppressive. We developed this technique to enable the study of solar simulated UV radiation dose responses and determined Immune Protection Factors (IPFs) for six commercially available sunscreens based on limits of protection from the dose response data. We found that the IPF did not correlate with the SPF and that protection from erythema therefore cannot be used to predict protection of the immune system. However, IPF was significantly correlated to the UVA protective capability of the sunscreens, indicating that sunscreen protection from UVA is important for prevention of immunosuppression. We recommend that sunscreens should be rated against their immune protective capability to provide a better indication of their ability to protect against skin cancer.

• The Korean Journal of Community Living Science
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• v.22 no.3
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• pp.429-444
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• 2011

The objective of this study was to identify the risk factor and protection factor related to suicide ideation in each life course based on an ecological-system perspective. A questionnaire was carried out for 393 adolescents, 473 adults and 376 aged men living nationwide. The results are as follows. First, the suicide ideation was low with 1.78 points in the full mark of 5 points. Second, the difference in suicide ideation, depression, hopelessness, stress in the organic system variables, family solidarity in the micro system variables, intermediate system variables, residence, the existence/inexistence of counselling center and the influence of mass media in mezo system variables in each life course were significant. Third, the relative influence of organic system variables on the suicide ideation were largest in all life courses. Further, the depression and the influence of mass media in all life courses were a risk factor of suicide ideation and stress was also a risk factor of suicide ideation in the case of adolescents and the aged. When examining protection factors of suicide ideation, family solidarity, minute as it is, works as the protection factor of suicide ideation in the case of adolescents. For the adults, living in a metropolis was a protection factor from suicide ideation. For the aged, family solidarity, family history of suicide and adult children's attention to their friends and neighbors (intermediate system variable) were protection factors from suicide ideation. I suggested that policy, service, counseling and educational program proper to each life course were necessary to lower risk factors of suicide ideation and to improve protection factors.

• Journal of Ocean Engineering and Technology
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• v.30 no.2
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• pp.134-140
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• 2016

An envelope protection system is a control system that allows a submarine to operate freely using its own operational envelope without exceeding the structural limit, dynamic limit, and control input limit. In this paper, an envelope protection system for the pitch angle of a submarine is designed using a dynamic trim algorithm. A linear quadratic regulator and artificial neural network are used for the true dynamics approximation. A submarine maneuvering simulation program developed using experimental data is used to validate the designed envelope protection system. Simulation results show the effectiveness of the designed envelope protection system.

• Journal of Advanced Marine Engineering and Technology
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• v.37 no.3
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• pp.260-265
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• 2013

Impressed current cathodic protection (ICCP) system is one of the most promising corrosion protection methods. The Effect of ICCP system can be changed at diverse conditions. Particularly, temperature and relative humidity plays a crucial role in CP (Cathodic Protection) effect. Thus, in this study, the influence of temperature and relative humidity on concrete specimens was investigated. Specimens were concrete slab type with a base of $400mm{\times}400mm$ and height of 70mm. To enhance the effect of CP system, seawater was used as an electrolyte. Used anode for ICCP system was mixed metal oxide (MMO) titanium. Test factors were natural potential, CP potential, CP current, and 4-hour depolarization potential. From this study, it could be confirm that CP potential and current were highly influenced by temperature and relative humidity.

• Proceedings of the KIEE Conference
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• 2005.05a
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• pp.185-187
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• 2005

The reactor protection system is the most important function for the safe operation of nuclear powerplants (NPPs) in that such system protects a nuclear reactor tore whose damage can cause an enormous disaster to the nuclear facility and the public. A digital reactor protection system (DRPS) is being developed in KAERI for use in the newly-constructed NPPs and also for replacing the existing analog-type reactor Protection systems. In this paper, an software verification and validation (V&V) activities for DRPS, which are independent of the DRPS development processes, are described according to the software development life cycle. The main activities of DRPS V&V processes are the software planning documentations, the verification of software requirements specification (SRS) and software design specification (SDS), the verification of codes, the tests of the integrated software and system. Moreover, the software safety analysis and the software configuration management are involved in the DRPS V&V processes. All of the V&V activities are described, in detail, in this paper.

• IE interfaces
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• v.23 no.1
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• pp.68-77
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• 2010

Digital reactor protection system which consists of many identical modules, is fault- tolerant to provide high safety. The modules themselves including DSP(digital signal processing) card are also fault-tolerant in nature. This paper assesses the safety for being-designed digital reactor protection system of 2-out-of-4 G structure with lockout. Some interesting design alternatives are compared. Fault tree analysis for assessing system safety is performed by Relex software. The selected reactor protection system fully satisfies EPRIURD stipulation of mean failure time of 50 years.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 1996.11a
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• pp.76-79
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• 1996

This paper provides an overview or an introduction covering the nature of explosions, explosion protection techniques and explosion protection systems(EPS), It is not intended to be a result for the design or research of protection including explosion suppression, venting, isolation, and an explanation to the mechanical system.

• Journal of Electrical Engineering and Technology
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• v.8 no.5
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• pp.969-974
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• 2013

Protection issues in distribution systems which are to be operated in open and closed-loop modes in a smart grid are studied and a generalized protection setting method is proposed to meet the new requirements. The developed setting method assumes a conventional over-current protection scheme for the system with reclosers and over-current relays. In a closed-loop mode, it identifies protective devices that have to be sacrificed in order to maximize protection coordination for bidirectional fault current flow. The proposed setting method has been tested on many systems with different complexity and is proved effective.

• Convergence Security Journal
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• v.5 no.3
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• pp.33-41
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• 2005

Information can be leaked, changed, damaged and illegally used regardless of the intension of the information owner. Intrusion Detection Systems and Firewalls are used to protect the illegal accesses in the network. But these are the passive protection method, not the active protection method. They only react based on the predefined protection rules or only report to the administrator. In this paper, we develop the intrusion detection and protection system using Netfilter framework. The system makes the administrator's management easy and simple. Furthermore, it offers active protection mechanism against the intrusions.

• Fire Science and Engineering
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• v.4 no.2
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• pp.3-13
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• 1990

Fire Protection System is facilities that Control the fire by mechanic means. Buildings Over a Certain Scale is required this system. As the small from the fire extinguisher as the large to the sprinkler system of automatic fire extinguishing equipment the kinds are various. With the development of architecture technique while modern higher buildings are increased. As fire is a first product that human make, it performed many profits and services for our mankind. Sometimes as it is profitable fire or harmful fire, it takes charge of human's life culture. Therefore fire protection system is facilities that control the ]after fire by mechanic means Building over a certain scale is required this system. As the small from the fire extinguisher as the large to the sprinkler system of automatic fire extinguishing equipment, the kinds are various. With the development of architecture technique while modern Higher buildings are increased high level and fire prevent facilities aren't reached to that level. The object of this study is present the problem which appear from the analysis of place standard for fire protection facility. This study described as a following order. First. We are going to look history of the fire protection system and change course of that with the year and facility. Second, We say the frame system and special nature of the foreign fire prevent Act. Third. We understand the control reality of fire protection system. Fourth. We took out the merit of foreign fire prevent law and the problem of our current domestic system. The placing standard of proper fire protection facilities that be presented from this study are followed next. 1) We have reinforce sprinkler system placing standard for the fire extinguishing and check the spread of fire. 2) We must to be ruled the standard for keeping fire prevention system that are received reality and people's idea. 3) We should prepare lawful basis which can be place fire prevention center. 4) We have to correct the standard of use about complex building without mainuse and we take increase the real effectiveness of this. 5) We ought to match the use of current fire prevention act and the use of architecture law.