• 방사성폐기물학회지
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• 제17권2호
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• pp.235-243
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• 2019

원자력 사고 후 대기로 누출된 방사성물질이 지표 토양내 침적된 후 강우에 의하여 주변 환경으로 이동하여 지표수계를 오염시킨다. 지표 토양내 침적된 방사성핵종의 거동 평가를 위하여 수립된 지표 수계 및 토양 유실 모델의 주요 입력자료를 수집하여 분석하였다. 월성 원전이 위치한 낙동강권역의 하천과 호수에서의 물리적 특성과 주요 생물상의 변화를 파악하기 위해서 원전 주변 수생 환경의 조사 및 분석을 수행하였다. 이를 위해 국내 여러 기관에서 제공하는 수치지도, 수문자료, 수질 및 생태환경자료 등을 수집 분석하여 자료간 상호 연계성을 갖도록 체계적인 DB를 구축하였다. 구축된 수생환경 자료는 지표수계에 흡착된 방사성물질의 중장기 거동 평가를 위하여 수립된 지표수계 유동, 토사유실 및 생태계 모델의 기본 입력자료로 제공되어 종합적인 방사선영향평가에 활용될 예정이다.

• Smart Structures and Systems
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• 제23권6호
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• pp.653-667
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• 2019

Using cross-ties to connect cables together when forming a cable network is regarded as an efficient method of mitigating cable vibrations. Cross-ties have been extended and fixed on bridge decks or towers in some engineering applications. However, the dynamics of this kind of system need to be further studied, and the effects of extending cross-links to bridge decks/towers on the modal response of the system should be assessed in detail. In this paper, a system of two cables connected by an inter-supported cross-link with another lower cross-link extended to the ground is proposed and analyzed. The characteristic equation of the system is derived, and some limiting solutions in closed form of the system are derived. Roots of cable system with special configurations are also discussed, attention being given to the case when the two cables are identical. A predictable mode behavior was found when the stiffness of inter-connection cross-link and the cross-link extended to the ground were the same. The vector of mode energy distribution and the degree of mode localization index are proposed so as to distinguish global and local modes. The change of mode behaviors is further discussed in the case when the two cables are not identical. Effects of cross-link stiffness, cross-link location, mass-tension ratio, cable length ratio and frequency ratio on $1^{st}$ mode frequency and mode shape are addressed.

• Advances in aircraft and spacecraft science
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• 제6권2호
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• pp.145-156
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• 2019

As the industrial desire for a step change in productivity within the manufacture of composite structures increases, so does the interest in Through-Thickness Reinforcement technologies. As manufacturers look to increase the production rate, whilst reducing cost, Through-Thickness Reinforcement technologies represent valid methods to reinforce structural joints, as well as providing a potential alternative to mechanical fastening and bolting. The use of tufting promises to resolve the typically low delamination resistance, which is necessary when it comes to creating intersections within complex composite structures. Emerging methods include the use of 3D woven connectors, and orthogonally intersecting fibre packs, with the components secured by the selective insertion of microfasteners in the form of tufts. Intersections of this type are prevalent in aeronautical applications, as a typical connection to be found in aircraft wing structures, and their intersections with the composite skin and other structural elements. The common practice is to create back-to-back composite "L's", or to utilise a machined metallic connector, mechanically fastened to the remainder of the structure. 3D woven connectors and selective Through-Thickness Reinforcement promise to increase the ultimate load that the structure can bear, whilst reducing manufacturing complexity, increasing the load carrying capability and facilitating the automated production of parts of the composite structure. This paper provides an overview of the currently available methods for creating intersections within composite structures and compares them to alternatives involving the use of 3D woven connectors, and the application of selective Through-Thickness Reinforcement for enhanced damage tolerance. The use of tufts is investigated, and their effect on the load carrying ability of the structure is examined. The results of mechanical tests are presented for each of the methods described, and their failure characteristics examined.

• Structural Engineering and Mechanics
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• 제71권4호
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• pp.433-444
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• 2019

Shear studs are often used to connect steel girders and concrete deck to form a composite bridge system. The application of precast concrete deck to steel-concrete composite bridges can improve the strength of decks and reduce the shrinkage and creep effect on the long-term behavior of structures. How to ensure the connection between steel girders and concrete deck directly influences the composite behavior between steel girder and precast concrete deck as well as the behavior of the structure system. Compared with traditional multi-I girder systems, a twin-I girder composite bridge system is more simplified but may lead to additional requirements on the shear studs connecting steel girders and decks due to the larger girder spacing. Up to date, only very limited quantity of researches has been conducted regarding the behavior of shear studs on twin-I girder bridge systems. One convenient way for steel composite bridge system is to cast concrete deck in place with shear studs uniformly-distributed along the span direction. For steel composite bridge system using precast concrete deck, voids are included in the precast concrete deck segments, and they are casted with cast-in-place concrete after the concrete segments are erected. In this paper, several sets of push-out tests are conducted, which are used to investigate the heavier of shear studs within the voids in the precast concrete deck. The test data are analyzed and compared with those from finite element models. A simplified shear stud model is proposed using a beam element instead of solid elements. It is used in the finite element model analyses of the twin-I girder composite bridge system to relieve the computational efforts of the shear studs. Additionally, a parametric study is developed to find the effects of void size, void spacing, and shear stud diameter and spacing. Finally, the recommendations are given for the design of precast deck using void for twin I-girder bridge systems.

• 한국산업융합학회 논문집
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• 제21권6호
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• pp.395-408
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• 2018

Even after the Fukushima nuclear accident in 2011, the rate of production of electric energy using nuclear energy is increasing, but there is a great danger such as the radioactive waste produced when using nuclear power, the catastrophic accident of nuclear power plant, and connection with nuclear weapons. In particular, Cs present in the ionic form of alkaline elements has a long half-life (30.17 years) because it is readily absorbed by the organism and emits intense gamma rays, thus presenting a serious radiation hazard. Therefore, it must be completely removed before it can be released into the natural ecosystem, because it can adversely affect not only humans but also natural ecosystems. Many adsorbents and ion exchangers which have high Cs removal efficiency have been used in recent years to completely separate and remove by self separation in water. Many adsorbents and ion exchangers which have high Cs removal efficiency have been used in recent years to completely separate and remove by self separation in water. In addition, researches have been doing to synthesize magnetic materials with adsorbents such as HCF and PB, and it shows a great effect in the removal rate of Cs present in wastewater or the maximum Cs adsorption amount. In particular, when a magnetic material was applied, excellent results were obtained in which only Cs was selectively removed from other cations. However, new problems such as applicability in the sea where Cs is directly released, applicability in various pH ranges, and failure to preserve the magnetizing force possessed by the magnetic body have been found. However, researches using ferromagnetic field with stronger magnetic properties than those of magnetic bodies is considered to be insufficient. Therefore, it is considered that if the researches combining the ferromagnetic field with the magnetization ability and functional adsorbents more actively, the radioactive material Cs which adversely affects the natural ecosystem can be effectively removed.

• 산업융합연구
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• 제13권4호
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• pp.11-28
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• 2015

A company have to grow constantly. If a company does not grow and stagnant, it will be finally out of the market. The contemporary companies fully make use of M&A to search for new growth engines. The reason of companies using M&A as a important tool of a business strategy is the fastest way to achieve technology power, market power, competitiveness. The form of M&A was that leading companies take over smaller companies or merger and acquisition between small companies in the middle of 2000. But now, Mega mergers between industry leading companies often occur and especially domestic of course M&A of foreign companies occurs actively. These days the boom of stock market and the big companies are pouring on sale by restructuring, privatization and the basis of low interest will make the M&A market continuously. In this study, I suggest a solution of actual human resources management by analyzing proven M&A cases and search for various problems of a gap in the leadership and communication in connection with integration of organization culture after M&A. First of all, I arrange the theoretical concept of the subject and analyze the key factors of the success M&A cases, lastly I suggested a HR strategy after M&A. After M&A, HR strategy is ; First, a company have to build a organization culture which is that merger company accommodate a excellent organizational characteristic of predecessor company with consideration of culture difference. Second, M&A must proceed to remove of anxiety about the future and employment stability by excellent leaderships. Third, organization integration after M&A is influenced by the level of integration for that reason it was verified that M&A have to make progress by communication of each 2 organizations.

• 융합보안논문지
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• 제21권2호
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• pp.47-56
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• 2021

그래프 시각화 이론에 근간을 둔 네트워크 토폴로지 시각화는 복잡한 네트워크의 전체 구조와 노드간의 상호작용을 보다 이해하기 쉽게 만든다. 네트워크 토폴로지를 시각화하는 도구는 과거부터 많이 개발되었지만, 일정 수준의 기능을 갖춘 도구들은 도구마다 고유한 네트워크 구성 정보(노드의 식별자, 종류, 속성, 연결된 노드 등)를 입력으로 요구하기 때문에 범용적으로 사용하기 어렵다. 반면에 최소한의 네트워크 구성 정보인 노드간의 연결만을 사용하는 도구들은 네트워크의 실제 연결 형태를 표시하는 기능이 부족하다. 본 논문에서는 네트워크 노드간의 연결 정보만을 이용하여 토폴로지를 시각화하는 효율적인 방법을 제안한다. 이 방법은 네트워크에서 노드의 영향력을 나타내는 중심성 지수를 활용하여 중심노드를 찾고, 자식노드의 가중치를 이용하여 전체 노드들의 표시 영역을 동적 분할한 후 3D 공간 상에 노드들을 배치함으로써 토폴로지를 시각화한다. 매우 간단한 방법이지만 노드간의 연결 정보만으로 실제 네트워크 연결 형태를 시각화할 수 있다.

• International Journal of Computer Science & Network Security
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• 제21권2호
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• pp.171-180
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• 2021

Currently, hospitals and medical practices have a large amount of unstructured information, gathered in time at each ward or practice by physicians in a wide range of medical branches. The data requires processing in order to be able to extract relevant information, which can be used to improve the medical system. It is useful for a physician to have access to a patient's entire medical history when he or she is in an emergency situation, as relevant information can be found about the patient's problems such as: allergies to various medications, personal history, or hereditary collateral conditions etc. If the information exists in a structured form, the detection of diseases based on specific symptoms is much easier, faster and with a higher degree of accuracy. Thus, physicians may investigate certain pathological profiles and conduct cohort clinical trials, including comparing the profile of a particular patient with other similar profiles that already have a confirmed diagnosis. Involving information technology in this field will change so the time which the physicians should spend in front of the computer into a much more beneficial one, providing them with the possibility for more interaction with the patient while listening to the patient's needs. The expert system, described in the paper, is an application for medical diagnostic of the most frequently met conditions, based on logical programming and on the theory of probabilities. The system rationale is a search item in the field basic knowledge on the condition. The web application described in the paper is implemented for the ward of pathological anatomy of a hospital in Romania. It aims to ease the healthcare staff's work, to create a connection of communication at one click between the necessary wards and to reduce the time lost with bureaucratic proceedings. The software (made in PHP programming language, by writing directly in the source code) is developed in order to ease the healthcare staff's activity, being created in a simpler and as elegant way as possible.

• 대한건축학회논문집:계획계
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• 제35권12호
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• pp.83-92
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• 2019

The purpose of this study is to analyze the continuous forms of time and space that work as architectural design principles of the Memorial to the Murdered Jews of Europe (Jewish Memorial). Continuity is divided into two, physical and non-physical attributes. The former extends from small installations to furnitures, finishes, spatial composition, and even spatial networks that complete architecture, and the latter is tied to time, from traditional to historical, developmental, commemorative or memorial elements. They are inherent in architecture as continuous forms. The Jewish Memorial is analyzed by the analysing framework of these two items. The analysis of the two layers can be summarized as follows; physical continuity is found in the space networks of the Memorial's inside and outside, the undulating spaces, the finishes, the small furnitures and installations, the entrances of staircases, the expanded underground of the ground order, and non-physical continuity manifests in the topological variation of spatiality, the morphological development of memorial architecture, the connection of semantic sense of space, and the superposition of historicity and modernity. These forms of continuity do not aestheticize the German enormity history, but make the meaning of the Memorial into non-superficial, in-depth architecture as a monument. Thus, the results of this study show that physical and non-physical continuity should be considered as the important design principles of architecture that makes the Memorial architecture possible.

• 한국도서관정보학회지
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• 제51권4호
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• pp.211-230
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• 2020

본 연구는 국가연구개발사업 성과로 발생한 최종보고서 기재항목 기준을 마련하여 데이터베이스 품질 향상과 관리 효율성 제고에 기여하고자 한다. 이를 위하여 과학기술정보통신부의 49개 산하기관에서 제출한 최종보고서를 수집하고 기관별 샘플을 선정하였다. 과학기술기본법 시행규칙의 최종보고서·요약서 서식과 대조하여 구성요소와 기재항목을 정립하고, 국가연구개발정보표준과 연계현황을 분석하여 최종보고서의 고유항목을 도출하였다. 기재항목은 중요도에 따라서 주요, 선택으로 구분하고 기재항목의 기입 위치를 제안하였다. 이와 같이 최종보고서 기재항목의 표준화가 진행되면, 데이터베이스 구축 시 메타데이터 추출 자동화와 보고서 메타데이터의 품질 향상을 기대해볼 수 있다.