• Convergence Security Journal
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• v.19 no.4
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• pp.97-105
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• 2019

With the possibility of wireless control of the aircraft by Nicola Tesla, Unmanned Aerial Vehicle(UAV) was mainly used for military and defense purposes with the rapid development through World War I and II. As civilian applications of unmanned aerial vehicles have expanded, they have been used with various services, and attempts have been made to control various environmental changes and risk factors of unmanned aerial vehicles. However, GPS spoofing, Jamming attack and security accidents are occurring due to the communication in the unmaned aerial vehicle system or the security vulnerability of the unmanned aerial vehicle itself. In order to secure introduction of Unmanned aerial vehicle, South Korea has established Unmanned Aerial Vehicle verification system called Airworthiness Certification. However, the existing cerfication system is more focused on test flight, design and structure's safety and reliability. In this paper, we propose a unmanned aerial vehicle system model and propose security functional requirements on unmanned aerial vehicle system in the corresponding system model for secure-introduction of Unmanned Aerial Vehicle. We suggest the development direction of verification technology. From this proposal, future development directions of evaluation and verification technology of Unmanned Aerial Vehicle will be presented.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2000.11a
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• pp.42-42
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• 2000

패선/구부림 가공은 백판지의 후가공의 일부분으로서 통상적으로 고평량인 백판지를 소비 자에게 맞는 형태로 가공하는 한 공정으로서 접는 공정을 용이하게 하기 위하여 종이 표면 에 패선을 넣어 구부려 접게 되는데 이때 구부리는 면의 표면적의 증가와 내부에서 외부로 향하는 Stress 에 의하여 종이의 표면층이 터지는 현상이 발생하기도 한다.이러한 터짐을 방지하면서 구부립 가공을 하기 위하여 백판지에 요구되는 특성은 여러 가지가 있으며 특히 고평량인 경우에는 종이가 구부러지면서 변형이 크게되는 만큼 외부로 밀리는 힘이 더욱크 게 작용하게 되고 이 힘을 충분히 수용할 수 있는 종이 자체의 강도가 펼요하게 되는데 본 연구에서는 다층판지의 원료특성과 판지특성등이 패션/구부림 가공적성과 연관성을 밝혀내 어 향후 연구방향의 기초를 삼고자 한다. 본 실험에서는 실험실적 결과와 실제 제품에서와의 차이를 최소화 하기 위하여 현장에서 생산되는 백판지를 사용하였으며 백판지의 각층을 구성하는 원료특성과의 상관관계까지 고 려하여 대전공장에서 생산되는 원료의 특성을 분석하고 같은 시간대의 제품과 비교펑가하는 방법을 취하였다. 각각의 원료 특성과 제품특성 (구부러짐 특성) . 공정조건등의 자료를 일정기간 취합하여 S Statisca 를 사용한 통계분석을 하였으며 1차 분석 결과 종이무성에 미치는 영향이 큰 수분 함량과 표면층의 원료구성 (Softwood 함량) 이 일차적으로 영향을 크게 미치며 종이 특성 으로는 CD 방향 터짐과 관련하여 MD 방향 인장, 내절, CD방향 강성등이 상관관계지수 0 0.7 이상으로 비교적 관계가 깊은 것으로 나타나며 인장과 신장율의 곱인 Toughness는 상 대적으로 낮아 터짐 지수로 활용하기는 어려울 것으로 판단되며 또한 신장율도 0.5 수준으 로 나타나며 패선구부러짐에 따른 층간구조변화에 따른 층간결합력이 영향이 있을 것으로 추측은 되었으나 분석결과 0.5 수준인 것으로 나타났다. 또한 CD 방향과 MD 방향의 터짐 성 상관관계도 0.5 이상인 것으로 나타나 섬유배향성도 패선/구부림 가공적성과 관련이 있 는 것으로 나타남으로서 패선/구부림 적성향상은 원료뿐만 아니라 초지공정조건에서도 향상 될 수 있는 것으로 나타났다. 향후 보다 세분화한 분석 및 도공층의 역할이 펼요할 것으로 판단되며 또한 지층구조분석 을 통한 Modeling 도 필요한 것으로 판단된다.

• Journal of Powder Materials
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• v.25 no.2
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• pp.144-150
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• 2018

$Al_2O_3-SiC$ ceramic composites are produced using pressureless sintering, and their plasma resistance, electrical resistance, and mechanical properties are evaluated to confirm their applicability as electrostatic-discharge-safe components for semiconductor devices. Through the addition of Mg and Y nitrate sintering aids, it is confirmed that even if SiC content exceeded 10%, complete densification is possible by pressureless sintering. By the uniform distribution of SiC, the total grain growth is suppressed to about $1{\mu}m$; thus an $Al_2O_3-SiC$ sintered body with a high strength over 600 MPa is obtained. The optimum amount of SiC to satisfy all the desired properties of electrostatic-discharge-safe ceramic components is obtained by finding the correlation between the plasma resistance and the electrical resistivity as a function of SiC amount.

• Journal of Digital Convergence
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• v.13 no.7
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• pp.393-402
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• 2015

This study used 236 users of individual rehabilitation system in the regions of Daejeon, Sejong, Chungnam and Chungbuk to review the effects that stressors have on the depression. During this process, the moderating effect of the factor, 'perception of hope', was verified. The data were analyzed using PASW Statistics 18.0. Major findings are as follows; First, the depression found in study subjects was higher than average. Second, there was a significant difference in the depression across groups in accordance with age, residential area, education level, social participation. Third, factors affecting the depression were identified to be residential area, social participation, health, economy and family of stressors, hope. Fourth, hope appeared to have a moderating effect in the relation between health, economy, family of stressors and depression. Based on these findings, the study presents practical and integrated measures to deter depression users of individual rehabilitation system.

• Journal of the Korean Institute of Gas
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• v.18 no.4
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• pp.35-43
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• 2014

Usage of the inorganic floor finishing material can be advantageous to overcome some problems of traditional organic-based floor finishing material used for hazardous material storage facilities. A spark can be produced by physical impact between the flooring and the flooring disposal equipment while removing the existing flooring. In order to prevent a fire hazard, which may be caused the spark, it is feasible that a construction can be implemented without removing the existing flooring. Moreover, the top coating material containing an antistatic agent is effective to prevent secondary damage caused by static electricity after finishing the construction of the flooring. Therefore, the inorganic floor finishing material of the this study is expected to be beneficial for safety management and economical aspect for inspectors.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.44 no.6 s.360
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• pp.31-39
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• 2007

In this paper, a system for real-time or periodic measurement and analysis of RF parameters such as forward transmit power and pilot power in CDMA base station systems is proposed. Such RF characteristic parameter measurement can be prevented from system fault and used to achieve optimal service quality and maximum investment return through cell coverage expansion, subscriber capacity increase and so on. For forward power measurement, the local oscillator frequency for the detector is varied so that the transmit power for all channels can be measured. The channel power measurement can be used to analyze the variation in transmit power for changes in voice traffic. By comparing to forward $E_c/I_o$, the pilot channel power can be deducted, which can be used to determine uy degradation in transmit section modules such as the high dover amplifier. Since an accurate analysis of carefully measured data using the CDMA level detector must be made, the system is designed so that measurement errors due to changes in crest factor with modulation method can be overcome.

• Korean Journal of Agricultural Science
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• v.10 no.1
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• pp.146-155
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• 1983

Fundamental study was carried out to elucidate the mechanisms of biological degradation of dyestuff in environments. A few bacterial strains which were capable of degrading amarnath were obtained from soil through an extensive screening program and identified by microbiolological properties. Conditions for bacterial growth and amaranth degradation were characterized and optimized, and the degradation products were identified. The results were as follows. 1. The most active strain A12-1 to be capable of degradation of amaranth was identified as Pseudomonas sp. 2. Optimal conditions for growth of the strain A12-1 were:$35^{\circ}C$ and pH 7.5, and growth was markedly increaesd by aeration. 3. Degradation of amaranth by the strain was accessed under similiar conditions for growth, however significantly inhibited when the culture was aerated. 4. Both bacterial growth and amaranth degradation were gradually decreased with increased concentration of amaranth in the culture. 5. Reaction of the crude enzyme from the strain A12-1 was optimal at $35^{\circ}C$ and pH 7.5 for degrading amaranth. 6. Sodium naphthionate and R-amino salt were found to be the products of amaranth degradation by the strain A12-1.

• Computational Structural Engineering
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• v.9 no.2
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• pp.143-151
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• 1996

The optimal design for Electro-magnetic Launcher (EML : Rail Gun) considering structural and electrical constraints are presented. For the structure of EML under high pulsed currency, the cross section is minimized subject to maximum stress of each element(rail, side wall, ceramic, and steel) within allowable stress and preload limits. The electrical constraint is the effective ceramic thickness which prevents the eddy current effect reducing the performance of EML. The stress analysis and optimization procedure of 90mm EML is conducted with ANSYS Code. The optimal design under preload is reduced to 53% of area compared with optimal design without preload. In case of rail with arc angle .theta.=45.deg., the performance of EML is the best among the other rail arc angles. The optimal design for rail with arc angle .theta.=45.deg., results in the reduction of 9% of area and 10.4% of deformation compared with Fahrenthold's design. The optimal preload 59.8MPa is much lower than Fahrenthold's design(186MPa). The results show that the optimal design of EML meets the design requirements.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.18 no.3
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• pp.68-83
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• 2019

The number of pedestrian traffic accident fatalities is three times the number of car accidents in South Korea. Serious accidents are caused especially at intersections when the vehicle turns to their right. Various pedestrian collision warning services have been developed, but they are insufficient to prevent dangerous pedestrians. In this study, P2CWS is developed to warn approaching vehicles based on the pedestrians' characteristics. In order to evaluate the performance of the service, actual pedestrian data were collected at the intersection of Daejeon, and comparative analysis was carried out according to pedestrian characteristics. As a result, the performance analysis showed a higher accordance when the characteristics of the pedestrian is considered. Accordingly, we can conclude that identifying pedestrian characteristics in predicting the pedestrian crossing is important.

• Journal of Digital Convergence
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• v.17 no.8
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• pp.257-264
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• 2019

This study was conducted to investigate the effect of 70% ethanol extract (DR) on the mast cell-mediated allergic contact dermatitis induced by dinitrofluorobenzene in BALB / c mice, which affects the cell activity by antigen in RBL-2H3 mast cells Respectively. The ethanol extracts of RBL-2H3 cells activated by DNP-HSA and anti-DNP IgE antibodies inhibited the secretion of ${\beta}$-hexosaminidase, histamine, and IL-4 and $TNF-{\alpha}$ Production was suppressed. In the DNFB-induced contact allergic dermatitis animal model, treatment with ethanol extract reduced ear swelling and inhibited serum histamine and IL-4 secretion, and DR treatment effectively prevented mast cell infiltration in dermatitis-induced areas. As a result, the ethanol extract may be used as a therapeutic agent for mast cell-mediated allergic diseases such as atopic dermatitis.