• Journal of Korean Society of Disaster and Security
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• v.16 no.1
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• pp.91-103
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• 2023

This study aims to investigate the dynamic fracture characteristics of rocks and rock-like materials subjected to the Nonex Rock Cracker (NRC), a vapor pressure crushing agent that produces vapor pressure by instantaneously vaporizing a liquid mixture crystallized through the thermite reaction. Furthermore, the study seeks to develop an analytical technique for predicting the fracture pattern. A dynamic fracture test was performed on a PMMA block, an artificial brittle material, using the NRC. High-speed cameras and dynamic pressure gauges were employed to capture the moment of vapor pressure generation and measure the vapor pressure-time history, respectively. The 2-dimensional Dynamic Fracture Process Analysis (2D DFPA) was used to simulate the fracture process caused by the vapor pressure, with the applied pressure determined based on the vapor pressure-time history. The proposed analytical method was used to examine various fracture patterns with respect to granite material and high-performance explosives.

• Explosives and Blasting
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• v.22 no.1
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• pp.75-80
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• 2004

최근 도심지의 가속화에 따라 시가지 인근에서의 암반굴착이 활성화되고 있으며, 특히 보안을 요하는 구조물에 근접한 발과 또는 가동중의 설비 가까이 에서 발파굴착을 실시해야하는 등 주변환경을 충분히 고려하여 진동, 소음 및 비산을 효과적으로 제어할 수 있는 발파기술이 요구되고 있다. 이와 같은 배경에서 미진동 발파굴착을 위하여 콘크리트 파쇄기, 팽창성 파쇄제 등이 개발되어 실용화되고 있다. 국내에서는 (주)한화가 콘크리트 파쇄기(Finecker)를 개발하여 공급해 왔으며, (주)고려 노벨 화약에서는 저폭속(2,000 m/s) 화약을 2중의 Air Gap을 이용하여 진동 및 소음 제어하는 미진동 발파용 화약(Kinecker)을 출시하여 공급하고 있다. 이에 Kinecker의 원리와 특징 그리고 현장적용 사례 및 발파패턴을 소개하고자 한다.

• Proceedings of the Korea Contents Association Conference
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• 2003.05a
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• pp.227-230
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• 2003

A system connected in Internet can be intruded by cracker via several systems. This paper proposes an efficient traceback model in order to trace a route of crackers. The traceback system is composed of a traceback server model and a traceback client model, As transmitting intrusion information from an area where client agent is installed to traceback server, the system distinguishes which systems are used as intrusion route. The traceback system can retrace intrusion route efficiently in an area where a traceback client is installed.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2018.05a
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• pp.261-264
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• 2018

2017년 비트코인을 비롯한 암호화폐 열풍이 뜨겁게 강타하면서 이를 구현하는데 활용된 블록체인(Blockchain) 기술이 주목받기 시작했다. 분산원장 기술(Distributed Ledger Technology)을 기반으로 만들어진 블록체인의 가장 큰 장점은 보안성을 높일 수 있다는 것이다. 이 기술을 챗봇(Chatbot) 개발에 접목시켜 크래커(Cracker)의 공격에 효율적으로 대응할 수 있고, 고객의 개인정보를 한 단계 더 안전하게 관리할 수 있다. 이러한 기술은 다양한 분야 중에서도 특히 데이터를 기반으로 발전하는 기술에 활용 가능성이 높을 것으로 전망되며, 이 논문에서는 블록체인 기술이 챗봇에 적용된 사례에 대해 분석한다.

• Proceedings of the Korea Information Assurance Society Conference
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• 2004.05a
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• pp.145-151
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• 2004

School Networks environment is implemented in many schools to support educational activities for networking resources required in teaching-teaming activities with government initiative. On the other hand, the open system in school which are used in internet in internet do considerable damage committed by intruder and cracker to the preservation of computer data and system due to second schools security state. Therefore this study is to present assortment in information resources of schools, security items and problem. finally, we give the effective and systematic metrics of estimates for security of secondary schools in information resources parts.

• ETRI Journal
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• v.34 no.5
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• pp.779-782
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• 2012

$CuIn_{1-x}Ga_xSe_2$ (CIGS) thin films are grown on Mo/soda lime glass using a reactive sputtering process in which a Se cracker is used to deliver reactive Se molecules. The Cu and $(In_{0.7}Ga_{0.3})_2Se_3$ targets are simultaneously sputtered under the delivery of reactive Se. The effects of Se flux on film composition are investigated. The Cu/(In+Ga) composition ratio increases as the Se flux increases at a plasma power of less than 30 W for the Cu target. The (112) crystal orientation becomes dominant, and crystal grain size is larger with Se flux. The power conversion efficiency of a solar cell fabricated using an 800-nm CIGS film is 8.5%.

• Proceedings of the Culinary Society of Korean Academy Conference
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• 2005.10a
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• pp.61-86
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• 2005

Kimchi power made by kimchi fermentation and freeze-drying was added to Western foods of sauce, soup, pizza, cracker and bread. Flavor qualities of the processed fusionfoods were evaluated by analyzing volatile compounds and sensory evaluation. The optimum condition of kimchi fermented for the best flavor quality of freeze-drying was the ranges of pH4.0${\sim}$pH4.7 and acidity 0.5${\sim}$0.8. The number of volatile compounds identified from extracts of the freeze-dried kimchi powder was 24, which contained 7 alcohols, 5 esters, 5 acids, 3 sulfur-containing compounds, 2 aldehydes, 1 oxygen-containing and 1 other. Among the identified compounds, the most abundant compound was eugenol(39.40%), followed as the order of dodecanoic acid(4.91%), acetic acid(1.70%), methyl 2-propenyl disulfide(1.52%), hexanal(1.51%) and 2-pentylfuran(1.18%). These compounds affected the flavor quality of kimchi powder.

• Journal of Institute of Convergence Technology
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• v.11 no.1
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• pp.13-18
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• 2021

It is widely accepted that the prevention of global warming requires significant reductions in greenhouse gases, particularly CO₂ emissions. Although fossil fuel-based power plants account for the majority of CO₂ emissions, it is urgent to reduce CO₂ emissions in industries that emit large amounts of CO₂ such as steel, petrochemical, and oil refining. This paper examines the current status of CO₂ emission in the domestic oil refining industry and CO₂ emission sources in each unit process in the oil refining industry. Focusing on the previously developed CO₂ capture process, cases and applicability of greenhouse gas reduction in FCC and hydrogen manufacturing processes, which are major processes constituting the oil refining industry, are reviewed.

• The Journal of the Korea institute of electronic communication sciences
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• v.4 no.3
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• pp.217-223
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• 2009

Recently, the development of the various network method can generate serious social problems. So, it is highly required to control security of network. These problems related security will be developed and keep up to confront with anti-security field such as hacking, cracking. The way to preserve security from hacker or cracker without developing new cryptographic algorithm is keeping the state of anti-cryptanalysis in a prescribed time by means of extending key-length. In this paper, the proposed montgomery multiplication structured unit array method in carry generated part and variable length multiplication for eliminating bottle neck effect with the RSA cryptosystem. Therefore, this proposed montgomery multiplier enforce the real time processing and prevent outer cracking.

• Journal of the Korea Convergence Society
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• v.5 no.2
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• pp.1-6
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• 2014

Latest Smart TV is rapidly increasing in prevalence. Smart-TV can provide reserve-service, training-service, and game service to user. Smart-TV need standard API for user requested app to run it. In this case, the cracker can run Malicious apps or user-request contents to modify it by analysis of the vulnerability of the smart-TV platform. Therefore, we modify the extension API on Smart-TV to prevent hacking. Our proposed research method can support that device is illegal in Smart-TV device can prevent unauthorized access.