• 반도체디스플레이기술학회지
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• 제18권1호
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• pp.74-78
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• 2019

As software becomes larger and network technology develops, the management of distributed data becomes more popular. Therefore, it is becoming increasingly important to use blockchain technology that can guarantee the integrity of data in various fields by utilizing existing infrastructure. Blockchain is a distributed computing technology that ensures that servers participating in a network maintain and manage data according to specific agreement algorithms and rules to ensure integrity. As smart contracts are applied, not only passwords but also various services to be applied to the code. In order to reinforce existing research on smart contract applied to the blockchain, we proposed a dynamic conditional rule of smart contract that can formalize rules of smart contract by introducing ontology and SWRL and manage rules dynamically in various situations. In the previous research, there is a module that receives the upper rule in the blockchain network, and the rule layer is formed according to this module. However, for every transaction request, it is a lot of resources to check the top rule in a blockchain network, or to provide it to every blockchain network by a reputable organization every time the rule is updated. To solve this problem, we propose to separate the module responsible for the upper rule into an independent server. Since the module responsible for the above rules is separated into servers, the rules underlying the service may be transformed or attacked in the middleware. Therefore, the security mechanism using TLS and PKI is added as an agent in consideration of the security factor. In this way, the benefits of computing resource management and security can be achieved at the same time.

• 한국물환경학회지
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• 제36권5호
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• pp.385-391
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• 2020

Soil loss is a serious problem frequently caused by local torrential rainfalls due to climate change. In particular, soil loss is occurring in agricultural areas rather than urban areas, and many pollutants are introduced into rivers, causing environmental problems. To reduce soil loss, the Ministry of Environment has designated and managed non-point source management areas. The Jaun-district in Hongcheon-gun, which was designed as a non-point pollution source management area in Gangwon-do, is located in the upper stream of Soyang Lake. Most of the agricultural fields are composed of highland agriculture fields. The highland agricultural fields in the Jaun-district are also composed of large-scale farming areas, and the ditches located near the agricultural fields have been illegally used for farmland. Therefore, the local government in Hongcheon-gun is conducting a project to restore the ditches occupied by agricultural fields. However, an analysis of the amount of soil loss that can be reduced by the restoration of the ditches has not been conducted yet. Thus, the purpose of this study was to analyze the effect of reducing the soil loss from the restoration of the ditches used as agricultural fields in the Jaun-district. The SATEEC L Module was used to analyze the reduction in soil loss by ditch restoration. The SATEEC L Module was constructed to estimate the LS factor using Moore and Burch's method after calculating the slope length using the digital elevation model and the maximum allowable slope length. The LS factor and the USLE formula were used to estimate the amount of soil loss that could be reduced by ditch restoration. The analysis showed that the ditch restoration could reduce about 16.6% of the soil loss in the Jaun-district. The results of this study will contribute to the study of methods to reduce soil loss in non-point pollution management areas.

• Geomechanics and Engineering
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• 제23권3호
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• pp.275-287
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• 2020

Rectangular barrettes have been increasingly used as foundations for many infrastructure projects, but the vertical vibration of a barrette has been rarely addressed theoretically. This paper presents an analysis method of dynamic response for a rectangular barrette subjected to a time-harmonic vertical force with the aid of a modified Vlasov foundation model in multilayered viscoelastic soil. The barrette-soil system is modeled as a continuum, the vertical continuous displacement model for the barrette and soil is proposed. The governing equations of the barrette-soil system and the boundary conditions are obtained and the vertical shaft resistance of barrette is established by employing Hamilton's principle for the system and thin layer element, respectively. The physical meaning of the governing equations and shaft resistance is interpreted. The iterative solution algorithm flow is proposed to obtain the dynamic response of barrette. Good agreement of the analysis and comparison confirms the correctness of the present solution. A parametric study is further used to demonstrate the effects of cross section aspect ratio of barrettes, depth of soil column, and module ratio of substratum to the upper soil layers on the complex barrette-head stiffness and the resistance stiffness.

• 산학경영연구
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• 제22권1호
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• pp.1-25
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• 2009

일반적으로 공기업의 문제는 경제적 합리성이라는 속성과 너무 괴리되어 있다는 점에서 비롯되어 우리나라의 경우 정부 상위관리기관과 정치권의 낙하산 인사의 대상으로 악용되며 노조와의 유착 등으로 인한 비능율과 부패의 온상처럼 비쳐져왔다. 이에 많은 사람들이 공기업을 개혁해야 한다는 생각을 하게 되었다. 앞으로의 공기업 개혁방향은 명확하다. 기간산업 등 민영화가 곤란한 부문은 정부의 소유 및 통제 하에 공기업 효율성을 제고시키는 경영관리 시스템을 구축해야 하고, 이외의 부문에서 효율화가 어려운 공기업은 민간에 경영권을 이양하는 민영화정책을 적극 고려하는 발상의 전환이 필요하다.

• 한국항해학회지
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• 제13권1호
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• pp.55-61
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• 1989

Nowadays much efforts for evaluating the productivity of port physical distribution system to meet the rapid change of the port and shipping circumstances has been made continuously all over the world. The major part of these efforts is the improvement of the productivity of cargo handling system. The cargo equipment system as infrastructure in the cargo handling system is organized well in some degrees, but the management system of manpower as upper structure is still remained in an insufficient degree. There is little study, so far, on a systematic research for the management of port labor gang, and even those were mainly depended on rule of thumb. The object of this study is to introduce the method of optimal allocation and assignment for the labor gang in single ship, which was suggested as a first stage in dealing with them generally. The problem of optimal allocation and assignment of the labor gang can be (I) formalized with multi-stage allocation and assignment of the labor gang can be. (II) dealt with two stages in form of hierarchic structure and moreover, (III) The optimal size of labor gang was obtained through dynamic programming from the point of minimizing the summation of labor gang in every stage, (IV) For the problem of optimal assignment, the optimal policy was determined at the point of minimizing the summation of movement between hatches.

• KIEAE Journal
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• 제15권5호
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• pp.21-33
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• 2015

Purpose: Domestically, a recent controversial part on Mixed-Use Development is its case that utilizes railroad sites among urban infrastructure. but most of all, a concern is being concentrated on the Mixed-Use Development that uses railroad depot. It has the advantage, which can give diversity and publicness to urban environment by using and planing the upper and bottom of railroad depot, a proximity site as Development Available Land. However, there are few cases except for only Yang-cheon APT in SinJeong railway depot as a domestic case even though a domestic concern about Mixed-Use Development is rising more than ever. Method: Accordingly, this study has something in common with a domestic case, dealing with a case of development in Hongkong that enhances efficiency for city space through Mixed-Use Development and solves various urban problems. Result: A purpose of this study, based on overall comprehension about Rail and Property Model of MTRC in Hongkong, is to figure out how it solve various problems in Mixed-Use Development using Railway Depot or stations in the base of Rail and Property Model of MTRC.

• Journal of information and communication convergence engineering
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• 제11권1호
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• pp.45-49
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• 2013

A compact radio frequency (RF) bandpass filter (BPF) in low temperature co-fired ceramic (LTCC) is suggested for WiMAX applications. The center frequency ($f_0$) of the BPF is 5.5 GHz and its pass band or 3-dB bandwidth is 700 MHz to cover all the three major bands, low and middle unlicensed national information infrastructure (U-NII; 5.15-5.35 GHz), World Radiocommunication Conference (5.47-5.725 GHz), and upper U-NII/industrial, scientific, and medical (ISM) (5.725-5.85 GHz), for the WiMAX frequency band. A lumped circuit element design-the 5th order capacitively coupled Chebyshev BPF topology-is adopted. In order to design a compact RF BPF, a very thin ($43.18{\mu}m$) ceramic layer is used in LTCC substrate. An interdigital BPF is also designed in silicon substrate to compare the size and performance of the lumped circuit element BPF. Due to the high relative dielectric constant (${\varepsilon}_r$ = 11.9) of the silicon substrate, the quarter-wavelength resonator of the interdigital BPF can be reduced. In comparison to the 5th order interdigital BPF at $f_0$ = 5.5 GHz, the lumped element design is 24% smaller in volume and has 17 and 7 dB better attenuation characteristics at $f_0{\pm}0.75$ GHz.

• 농촌계획
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• 제9권3호
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• pp.41-46
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• 2003

The study was focused on setting priority for future core technologies in rural development and resources using AHP. The technologies were derived by Delphi method. Evaluation criteria for the priority setting were decided as 'technology', 'market oriented', and 'public concerns' by council. The future core technologies were divided as four groups by importance and R&D level. Technologies in upper two groups were considered in the study. Group I had high importance and high R&D level. Group II had high importance and lower R&D level. Questionnaires were given to 9 specialists in agricultural resources. As the results, 'public concerns' was decided as a most important evaluation criterion. The most important technologies are "technology developing for animal feces and urine treatment, and restoration it to farm land" in group I, and "technology developing for agricultural by-products as energy source" in group II.

• 한국추진공학회지
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• 제23권2호
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• pp.87-94
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• 2019

액체로켓 추진기관 시험설비는 시험대상체가 상위 시스템에 장착되었을 때의 인터페이스 조건을 모사하여야 하며, 시험 시 파손이 발생할 수 있는 개발품의 특성상, 안전하게 시험이 이루어질 수 있게 구축되어야 한다. 이를 위해 추진기관 시험설비 기반시설은 안정적인 연소가 이루어지고 사고 시에도 안전이 보장되도록 구축되어야 한다. 본 논문에서는 액체로켓 엔진 추진기관 시험설비 기반시설의 구축 및 운영 시 고려해야 할 사항에 대해, 토목/건축, 시험 스탠드, 설비의 배치, 타 설비와의 운영 조합 및 공동구, 소화설비, 전력설비 측면에서 고찰하였다.

• 항공우주정책ㆍ법학회지
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• 제33권2호
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• pp.61-114
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• 2018

최근들어 '공역'은 뜨거운 이슈가 되었는데, 의외로 우리나라의 공역 법과 제도에 대해 전체적으로 설명된 자료는 없어, 민 군 공역 법제와 실무를 함께 정리하여 보았다. 우리나라의 항공법 분야는 적어도 법적인 측면에서는 민간항공기와 군용항공기 관련 법은 완전히 분리되어 있다. 국토부교통부장관은 "항공안전법"에서 부여된 각종 권한을 갖고 업무를 수행한다. 우리나라 항공관련 내용은 너무 많은 사항을 국토부 고시나 규정으로 규율하고 있고, 그 고시나 규정들도 상위 법규의 어떤 조항과 연결되는지 잘 알 수 없는 것들이 많다. 따라서, 현행 고시의 내용을 검토해서 가능한 법규명령으로 하도록 노력할 필요가 있고, 고시 내용도 위임된 사항에 한하여 구체적으로 명확하게 서술되도록 정비할 필요가 있다. 공역체계에 있어서는, 일반인이 이해하기에는 공역 분류체계가 너무 복잡하고, 법규와 실무의 괴리도 일부 있어 보인다. 따라서, 단순하면서도 실무현실에 부합하는 공역 분류 체계로 재정립해 보는 것은 어떤가 생각된다. 군에서 하는 공역이나 항공 관련 업무는 국토교통부장관으로부터 위탁받은 것과 군 고유의 권한을 명확히 구분해서 이해할 필요가 있다. 국토교통부 위탁사항과 관련해서는, 본래 국토교통부의 업무이기 때문에 관련 업무 지침 작성시 국토교통부와 긴밀히 협조해야 하고, 현재 국토교통부에서 국방부로 위탁한 것을 대부분 예하 비행단급까지 재위임하고 있는데 재위임 부대의 적정성을 한 번 고민해 볼 필요가 있고, 관련 지침의 작성 주체도 명확히 해 둘 필요가 있다. 군사작전활동으로서의 공역통제와 관련해서는, '노력의 통일'과 같은 공역통제에 관한 군사교리에 충실한 정책이나 지침이 필요하다.