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A Study on model for Records Management of Local Assembly to Embody Local Governance (로컬 거버넌스 실현을 위한 지방의회 기록관리 모형에 관한 연구)

  • Choi, Youn-Ju
    • The Korean Journal of Archival Studies
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    • no.14
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    • pp.241-288
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    • 2006
  • For cope with the participating government promoted local decentralization of the present time, local governments are coming to aim at the realization of local governance. Local governance refers to a way of solving public problems of urban area through partnership which is a collaboration and participation based on 'relationship' among diverse interested parties such as executive authority of policy, private sectors. First of all, it is most important task to make transparency and responsibility of all people and networks by themselves through sharing information. With like this kind of a background, local assembly is an momentos body of local governance because it is a decision making organization at the same time as a representative organization of local residents, and it has a relationship of 'check and balance' with chiefs of local governments as an organization monitoring and supervising the administration of an executive authority. Not the less, information about local assembly does not open to the public or exist. Even some informations open to the public, they are not enough to be settled distrust and low-valuation by civil society. Now Local assembly is face to a point that improve over all of record management. This study is based like this critical mind, then, it examines throughly local assembly's realities by suggestion with reforming plan of record management. Record can embody true values when record management practices indefatigably through prudential system from production until preservation. Accordingly, this study suggests management of transaction unit without the omission of record. Also this study is satisfy the condition of Korean record management system with proposals of record management policy and establishment of record center. At the conclusion of study, it puts effects into shape that local assembly secure transparency and responsibility and organize local governance by record management.

Microbial Activity Analysis for the Selectively Sterilizing of Government-controlled Bulk Public Archives (대량 공공 기록물의 선별적 소독을 위한 미생물 활성도 분석 연구)

  • Kim, Dae Woon;Park, Ka Young;Kim, Ji Won;Kang, Dai Ill
    • Journal of Conservation Science
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    • v.34 no.6
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    • pp.443-458
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    • 2018
  • An archive is a collection of documents or records. Currently, most archived documents are made of paper. Paper is susceptible to biological damage and deterioration due to its material properties. To control the biological damage, treatment with chemical disinfectants and control of the storage environment are often used. In government-controlled bulk public archives, all documents are chemically sterilized before storage. However, an extremely large quantity of public records have been produced, and storage space and conservation management are gradually reaching their limits. In this study, 60 species of microbes were identified using a genetic method. We successfully applied the adenosine triphosphate (ATP) bioluminescence method to detect microbial contamination on paper documents. A calibration curve of the ATP bioluminescence as a function of the microbe quantity was obtained, and the microbial activity on non-sterilized paper archives from 1951 was analyzed using an ATP luminometer. It was found that the microbial activity was suppressed or reduced in climate-controlled storage environments at $22^{\circ}C$ and 55% relative humidity. We anticipate that these results will be used to establish selective sterilization systems for government-controlled bulk public archives.

Studies in Biomechanical Properties on Brain-spinal Cord Response Mechanism by Human Posture Control Ability (자세조절능력에 따른 뇌-척수 신경 반응기전의 역학적 해석)

  • Yoo, Kyoung-Seok
    • 한국체육학회지인문사회과학편
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    • v.58 no.6
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    • pp.449-459
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    • 2019
  • The purpose of this study is to identify how postural mechanics affects postural control on balance and stability by using frequency analysis technique from the kinematic data acquired during the one leg standing posture. For this purpose, the experimental group consisted of two groups, the normal group (n=6) and the national Gymnastics group (n=6). Displacement data of CoP were analyzed by frequency analysis of rambling (RM) and trembling (TR) by FFT signal processing. As a results, there was a significant difference in evaluating the stabilization index between the two groups with the eyes open and closed one leg stnading (p <.05). The cause of the difference was found to be the output of the maximum amplitude of RM (f1) and TR (f2) (p <.05). In particular, in the low frequency RM of 8-9 Hz, which is a natural frequency of signal wave involved in postural feedback feedback, the main frequency appeared to be performs the exercise mechanism of stable brain posture control. And in the high frequency TM of 120-135 Hz, it is considered that the adaptation of the reflective muscle response is minimized to minimize posture shaking. In conclusion, this study provides evidence for the intrinsic main frequencies according to the postural control ability which affects the CNS in one leg standing.

Effect of Etching Treatment of SAPO-34 Catalyst on Dimethyl Ether to Olefins Reaction (DTO 반응에 미치는 SAPO-34 촉매의 식각 처리 효과)

  • Song, Kang;Yoon, Young-Chan;Park, Chu-Sik;Kim, Young-Ho
    • Applied Chemistry for Engineering
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    • v.32 no.1
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    • pp.20-27
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    • 2021
  • Effects of the etching treatment of SAPO-34 catalyst were investigated to improve the catalytic lifetime in DTO reaction. The aqueous NH3 solution was a more appropriate treatment agent which could control the degree of etching progress, compared to that of using a strong acid (HCl) or alkali (NaOH) solution. Therefore, the effect on characteristics and lifetime of SAPO-34 catalyst was observed using the treatment concentration and time of aqueous NH3 solution as variables. As the treatment concentration or time of aqueous NH3 solution increased, the growth of erosion was proceeded from the center of SAPO-34 crystal plane, and the acid site concentration and strength gradually decreased. Meanwhile, it was found that external surface area and mesopore volume of SAPO-34 catalyst increased at appropriate treatment conditions. When the treatment concentration and time were 0.05 M and 3 h, respectively, the lifetime of the treated SAPO-34 catalyst was the longest, and was significantly enhanced by ca. 36% (based on DME conversion of > 90%) compared to that of using the untreated catalyst. The model for the etching progress of SAPO-34 catalyst in a mild treatment process using aqueous NH3 solution was also proposed.

The Power Converter Circuit Characteristics for 3 kW Wireless Power Transmission (3 kW 무선 전력전송을 위한 전력 변환기 회로 특성)

  • Hwang, Lark-Hoon;Na, Seung-kwon;Kim, Jin Sun;Kang, Jin-hee
    • Journal of Advanced Navigation Technology
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    • v.24 no.6
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    • pp.566-572
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    • 2020
  • In a wireless power transmitter, the characteristics and effects of wireless power transmission between two induction coils are investigated, and a power converter circuit and a battery charger/discharger circuit using wireless power transmission technology are proposed. The advantage of wireless power transmitters and wireless chargers is that, instead of the existing plug-in-mounted wired charger (OBC; on-board charger), the user can wirelessly charge the battery without connecting the power source when charging power to the battery. There is. In addition, the advantage of wireless charging can bring about an energy efficiency improvement effect by using the secondary side rectifier circuit and the receiving coil, but the large-capacity long-distance wireless charging method has a limitation on the transmission distance, so many studies are currently being conducted. The purpose of the study is to study the transmitter circuit and receiver circuit of a wireless power transmission device using a primary coil, a secondary coil, and a half bridge series resonance converter, which can transmit power of a non-contact type power transmitter. As a result, a new topology was applied to improve the power transmission distance of the wireless charging system, and through an experiment according to each distance, the maximum efficiency (95.8%) was confirmed at an output of 3 kW at an 8 cm transmission distance.

A Four-Wheeled Mobile Robot with Omnidirectionality (전방향성을 갖는 네 바퀴 이동로봇)

  • Kang, Su Min;Sung, Young Whee
    • Journal of the Institute of Convergence Signal Processing
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    • v.23 no.1
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    • pp.21-27
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    • 2022
  • Traditional automobile or 2-wheeled robot have limitations on mobility because of their mechanical structure. As traditional automobile is being replaced by electric cars, robot technology is applied to the car industry. In robotics, many researchers worked on omnidirectional mobile robot and produced lots of noticeable results. However in many of the results, specialized wheels such as Mecanum wheels are required. That imposes restrictions on robot speed and outdoor driving. We proposed a 2-wheeled modular robot that has omnidirectional mobility without using specialized wheels. In this paper, we propose a 4-wheeled omnidirectional mobile robot that consists of those two modular robots. The proposed robot adopts electric brakes to combine wheel housings and the robot body or to separate wheel housings from the robot body. Two absolute-type encoders and four incremental encoders are used to control the position of the wheel housing and velocities of the wheels. The proposed robot has omnidirectional mobility and can move fast and outdoor with normal tire wheels. We implemented the proposed robot and the feasibility and stability of the robot is verified by two separate experiments.

Development of Registration Post-Processing Technology to Homogenize the Density of the Scan Data of Earthwork Sites (토공현장 스캔데이터 밀도 균일화를 위한 정합 후처리 기술 개발)

  • Kim, Yonggun;Park, Suyeul;Kim, Seok
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.42 no.5
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    • pp.689-699
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    • 2022
  • Recently, high productivity capabilities have been improved due to the application of advanced technologies in various industries, but in the construction industry, productivity improvements have been relatively low. Research on advanced technology for the construction industry is being conducted quickly to overcome the current low productivity. Among advanced technologies, 3D scan technology is widely used for creating 3D digital terrain models at construction sites. In particular, the 3D digital terrain model provides basic data for construction automation processes, such as earthwork machine guidance and control. The quality of the 3D digital terrain model has a lot of influence not only on the performance and acquisition environment of the 3D scanner, but also on the denoising, registration and merging process, which is a preprocessing process for creating a 3D digital terrain model after acquiring terrain scan data. Therefore, it is necessary to improve the terrain scan data processing performance. This study seeks to solve the problem of density inhomogeneity in terrain scan data that arises during the pre-processing step. The study suggests a 'pixel-based point cloud comparison algorithm' and verifies the performance of the algorithm using terrain scan data obtained at an actual earthwork site.

A Review on Ultrathin Ceramic-Coated Separators for Lithium Secondary Batteries using Deposition Processes (증착 기법을 이용한 리튬이차전지용 초박막 세라믹 코팅 분리막 기술)

  • Kim, Ucheol;Roh, Youngjoon;Choi, Seungyeop;Dzakpasu, Cyril Bubu;Lee, Yong Min
    • Journal of the Korean Electrochemical Society
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    • v.25 no.4
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    • pp.134-153
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    • 2022
  • Regardless of a trade-off relationship between energy density and safety, it is essential to improve both properties for future lithium secondary batteries. Especially, to improve the energy density of batteries further, not only thickness but also weight of separators including ceramic coating layers should be reduced continuously apart from the development of high-capacity electrode active materials. For this purpose, an attempt to replace conventional slurry coating methods with a deposition one has attracted much attention for securing comparable thermal stability while minimizing the thickness and weight of ceramic coating layer in the separator. This review introduces state-of-the-art technology on ceramic-coated separators (CCSs) manufactured by the deposition method. There are three representative processes to form a ceramic coating layer as follows: chemical vapor deposition (CVD), atomic layer deposition (ALD), and physical vapor deposition (PVD). Herein, we summarized the principle and advantages/disadvantages of each deposition method. Furthermore, each CCS was analyzed and compared in terms of its mechanical and thermal properties, air permeability, ionic conductivity, and electrochemical performance.

Effect of CEOs' Characteristics on Digital Transformation and Corporate Performance: Focusing on RSN Co., Ltd (최고경영자의 특성이 디지털 전환과 기업성과에 미치는 영향: (주)RSN중심으로)

  • Park, Soohwang;Jang, Kyungbae
    • Journal of Internet of Things and Convergence
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    • v.8 no.3
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    • pp.11-20
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    • 2022
  • Corporations operate within long term strategy. The Chief Executive Officer (CEO) makes decisions and has responsibility for all executive activities which affects the corporate performance. If the CEO makes strategic choices through reasonable decision making, it could affect corporate performance and corporate's rise and fall. So the CEO's decision making is very important. As rapid change in the digital technology environment happened, through digital transition, corporations have been working on increasing corporate performance by practical and academic methods. However prior research was restricted to CEO's affect on organization, innovation or innovative activities and there is a lack of research linking CEO's characteristics to digital transition and corporate performance. As the digital age is coming, research on how CEO's characteristics affect digital transition and corporate performance is direly needed. From the case of domestic Big Data corporation RSN Co. ltd's digital transition success, understanding characteristics of CEO, digital transition and corporate performance through prior researches, and developing research model and research proposition was set. Research was performed on RSN co. ltd's case analysis, and how characteristics of CEO's matter on digital transformation and corporate performance. As a result of the proposition, when the CEO conjugates digital technology, the corporation was able to successfully complete digital transition and it also affects corporate performance. Also, this research's other point is that CEO's may have limits on thoughtful decision making. It is judged that it is necessary to try an empirical study in the future.

Flexural Experiments on Reinforced Concrete Beams Strengthened with SHCC and Special Reinforcements (SHCC와 특수 보강근으로 보강된 철근콘크리트 보의 휨 성능 실험)

  • Chang-Jin Hyun;Ji-Seok Seo;Yun-Yong Kim
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.27 no.1
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    • pp.46-53
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    • 2023
  • In this paper, we evaluated the flexural performance of three types of reinforced concrete beams (SHCC-RB, SHCC-SB, SHCC-FRP) strengthened with ordinary steel rebar, very high strength (super strength) rebar, and FRP bars together with strain-hardening cement composite (SHCC). For this purpose, a series of beam specimens were manufactured and four-point load bending experiments were performed. As a result of the experiment, all specimens strengthened with SHCC exhibited tightly controlled flexural microcrakcs with the crack width of less than 100 ㎛. This is mostly due to the material properties of SHCC showing tensile strain hardening properties with multiple microcracks under uniaxial tension. The specimen SHCC-FRP showed lower initial cracking moment and yield flexural strength than SHCC-RB, whereas the maximum flexural strength of SHCC-FRP was superior to that of SHCC-RC. This is because the tensile strength of FRP bars is higher than that of ordinary steel reabr. The initial cracking moment of the beam specimen SHCC-SB was similar to that of SHCC-RB, but the yield flexural strength and maximum flexural strength of SHCC-SB were evaluated to be the highest.