• Title/Summary/Keyword: Contact point

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Consideration for defense preparedness against non-traditional security threats (focused on the threat of infectious diseases) (비전통 위협에 대한 국방 업무수행체계 유지방안 (감염병 위협 중심으로))

  • Kwon, Hyukjin;Shin, Donggyu;Shin, Youngjoo
    • Journal of Internet Computing and Services
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    • v.23 no.1
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    • pp.105-112
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    • 2022
  • The national defense requires uninterrupted decision-making, even under direct or indirect impacts on non-traditional threats such as infectious diseases. Since all work utilizes the information system, it is very important to ensure the availability of the information system. In particular, in terms of security management, defense work is being performed by dividing the network into a national defense network and a commercial Internet network. This study suggests a work execution plan that takes into account the efficiency of work performed on the Internet and the effectiveness of security through effective defense information system operation. It is necessary to minimize the network contact point between the national defense network and the commercial Internet, and to select a high-priority one among various tasks and operate it efficiently. For this purpose, actual cases were investigated for "A" institution and characteristics were presented. Through the targeted tasks and operation plans to improve the effectiveness of defense tasks and ensure security, presented in this paper, it will be possible to increase the availability of task performance even in non-traditional threats such as infectious diseases.

Vibration Analysis of Film Winding Core Automatic Supply System Using US Military Standards (미 군사규격을 적용한 권취 코어 자동공급장치의 진동해석)

  • Go, Jeong-Il;Park, Soo-Hyun;Hur, Jang-Wook
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.21 no.4
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    • pp.91-99
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    • 2022
  • By applying METHOD 514.8 of the US military standard MIL-STD-810H, vibration analysis of the winding core automatic feeding device was performed during vehicle transportation. The contact point between the LM guide and main support frame was weak in the vertical axis, transverse axis, and longitudinal axis during the transportation of the automatic winding core feeder vehicle, and the maximum equivalent stress was 236.31 MPa in the longitudinal axis. When random vibration was applied, the safety margin in the longitudinal direction was 0.26, indicating low safety. The safety margin was changed by increasing the damage factor to 0.1. Finally, the safety margin was improved to 3.48 to secure safety. Resonance occurred with a Q factor of 9.34 in the harmonic response to which the RMS value of the ASD data was input, and the vertical axis safety margin was derived as 0.16. When the damping factor was 0.15, the Q factor was 3.37, and resonance was avoided with a safety margin of 6.62.

Development of Automatic Peach Grading System using NIR Spectroscopy

  • Lee, Kang-J.;Choi, Kyu H.;Choi, Dong S.
    • Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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    • 2001.06a
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    • pp.1267-1267
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    • 2001
  • The existing fruit sorter has the method of tilting tray and extracting fruits by the action of solenoid or springs. In peaches, the most sort processing is supported by man because the sorter make fatal damage to peaches. In order to sustain commodity and quality of peach non-destructive, non-contact and real time based sorter was needed. This study was performed to develop peach sorter using near-infrared spectroscopy in real time and nondestructively. The prototype was developed to decrease internal and external damage of peach caused by the sorter, which had a way of extracting tray with it. To decrease positioning error of measuring sugar contents in peaches, fiber optic with two direction diverged was developed and attached to the prototype. The program for sorting and operating the prototype was developed using visual basic 6.0 language to measure several quality index such as chlorophyll, some defect, sugar contents. The all sorting result was saved to return farmers for being index of good quality production. Using the prototype, program and MLR(multiple linear regression) model, it was possible to estimate sugar content of peaches with the determination coefficient of 0.71 and SEC of 0.42bx using 16 wavelengths. The developed MLR model had determination coefficient of 0.69, and SEP of 0.49bx, it was better result than single point measurement of 1999's. The peach sweetness grading system based on NIR reflectance method, which consists of photodiode-array sensor, quartz-halogen lamp and fiber optic diverged two bundles for transmitting the light and detecting the reflected light, was developed and evaluated. It was possible to predict the soluble solid contents of peaches in real time and nondestructively using the system which had the accuracy of 91 percentage and the capacity of 7,200 peaches per an hour for grading 2 classes by sugar contents. Draining is one of important factors for production peaches having good qualities. The reason why one farm's product belows others could be estimated for bad draining, over-much nitrogen fertilizer, soil characteristics, etc. After this, the report saved by the peach grading system will have to be good materials to farmers for production high quality peaches. They could share the result or compare with others and diagnose their cultural practice.

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Research Trends of Technology Holding Companies and Suggestions for improving Corporate Performance : Focusing on the introduction of PMO (기술지주회사 연구동향과 기업성과 향상을 위한 제언 : Project Management Office(PMO) 도입을 중심으로)

  • Lee, Kangoh;Lee, Chanho
    • Journal of East Asia Management
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    • v.4 no.1
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    • pp.53-77
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    • 2023
  • Modern company faces an uncertain future and a competitive environment and are seeking new technologies and creative products to ensure the corporate growth and survival in the market through continuous innovation. "University Industry Cooperation(UIC)" is a point of contact for overcoming the crisis faced by companies and universities in this era and a cooperation platform for mutual prosperity. As a subsidiary of a university, "Technology Holding Company(THC)" is attracting attention as a new window for UIC in Korea. The role of THC is to establish and foster the business opportunities of their subsidiaries and to return investment profits to the university ecosystem again. But recently, the life cycle of technology is getting shorter, and the development cost is steadily increasing. In particular, with the increase of hybrid projects based on convergence and combination, the risk of conducting research(R&D) and new product development(NPD) projects is gradually increasing. A PMO refers to a project management organization that can contribute to improving the success rate of projects with increasing uncertainty by supporting project visibility and appropriate decision-making. The purpose of this study is to raise a research question on whether THC's corporate performance can be improved when "Project Management System(PMO Service)" is introduced into the subsidiary incubation system of THC. This study proposes several research methods to identify the relationship between the introduction of PMO and the corporate performance of THC.

Seismic retrofit of steel structures with re-centering friction devices using genetic algorithm and artificial neural network

  • Mohamed Noureldin;Masoum M. Gharagoz;Jinkoo Kim
    • Steel and Composite Structures
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    • v.47 no.2
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    • pp.167-184
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    • 2023
  • In this study, a new recentering friction device (RFD) to retrofit steel moment frame structures is introduced. The device provides both self-centering and energy dissipation capabilities for the retrofitted structure. A hybrid performance-based seismic design procedure considering multiple limit states is proposed for designing the device and the retrofitted structure. The design of the RFD is achieved by modifying the conventional performance-based seismic design (PBSD) procedure using computational intelligence techniques, namely, genetic algorithm (GA) and artificial neural network (ANN). Numerous nonlinear time-history response analyses (NLTHAs) are conducted on multi-degree of freedom (MDOF) and single-degree of freedom (SDOF) systems to train and validate the ANN to achieve high prediction accuracy. The proposed procedure and the new RFD are assessed using 2D and 3D models globally and locally. Globally, the effectiveness of the proposed device is assessed by conducting NLTHAs to check the maximum inter-story drift ratio (MIDR). Seismic fragilities of the retrofitted models are investigated by constructing fragility curves of the models for different limit states. After that, seismic life cycle cost (LCC) is estimated for the models with and without the retrofit. Locally, the stress concentration at the contact point of the RFD and the existing steel frame is checked being within acceptable limits using finite element modeling (FEM). The RFD showed its effectiveness in minimizing MIDR and eliminating residual drift for low to mid-rise steel frames models tested. GA and ANN proved to be crucial integrated parts in the modified PBSD to achieve the required seismic performance at different limit states with reasonable computational cost. ANN showed a very high prediction accuracy for transformation between MDOF and SDOF systems. Also, the proposed retrofit showed its efficiency in enhancing the seismic fragility and reducing the LCC significantly compared to the un-retrofitted models.

A Study on the Aesthetic Identity of Modern Eroticism Fashion from the Perspective of Jacques Lacan's Unconscious Theory -Focusing on Jouissance & Gaze Theory- (자크 라캉 무의식이론의 관점에서 본 현대 에로티시즘 패션의 미적 정체성 연구 -주이상스와 응시론을 중심으로-)

  • Jungwon Yang;Misuk Lee
    • Journal of Fashion Business
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    • v.27 no.2
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    • pp.124-139
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    • 2023
  • The purpose of this study is to determine the aesthetic identity of modern eroticism fashion in which the energy of desire is maximized through the 'jouissance' and 'gaze' of the unconscious theory of Jacques Lacan. The research method derived aesthetic identity after examining jouissance and gaze deeply related to eroticism in Lacan's theory of the unconscious by analyzing data of domestic and foreign monographs and prior research. Case analysis was limited to 2000 S/S to 2022 F/W. Based on prior research, it was analyzed mainly on clothing with eroticism characteristics of 'exposure, close contact, see-through, the conversion of underclothes into outer garments'. Results of the study are as follows. First, eroticism, which can be linked to Lacan's type of 'jouissance' with multiple meanings as the generating point of eroticism, has manifested itself in voyeuristic eroticism, fatale eroticism, masochistic eroticism, surplus eroticism, and sacred eroticism. Second, as eyes of unconscious desire, visual expression characteristics of 'gaze' appeared as anamorphosis, trompe l'oeil, and dépaysement. The identity of eroticism derived from Lacan's jouissance and the perspective of the desire gaze was divided into voyeuristic desire to gaze, fatal desire to gaze, masochistic desire to gaze, surplus desire to gaze, and sacred desire to gaze. Results of this study will expand theoretical horizons of eroticist fashion with a new interpretation of eroticism by combining Lacan's desire as a repressed and alienated subject within the human unconscious with the art that expands it.

Analysis of Bonding Characteristics of Ag-System Brazing Filler Metal (은계 필러메탈 브레이징 접합부의 특성 분석)

  • Soon-Gil Lee;Hwa-In Lee;Jin-Oh Son;Gwang-Il Ha;Bon-Heun Koo
    • Korean Journal of Materials Research
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    • v.33 no.5
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    • pp.214-221
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    • 2023
  • As a filler metal for lowering the melting point of Ag, many alloy metal candidates have emerged, such as cadmium, with zinc, manganese, nickel, and titanium as active metals. However, since cadmium is known to be harmful to the human body, Cd-free filler metals are now mainly used. Still, no study has been conducted comparing the characteristics of joints prepared with and without cadmium. In addition, studies have yet to be conducted comparing the typical characteristics of brazing filler metals with special structures, and the joint characteristics of brazing filler metals with available frames. In this study, the characteristics of junctions of silver-based intercalation metals were compared based on the type of filler metal additives, using a special structure, a filler metal sandwich structure, to protect the internal base metal. The general filler metal was compared using the structure, and the thickness of the filler metal according to the thickness was reached. A comparison of the characteristics of the junction was conducted to identify the characteristics of an intersection of silver-based brazing filler metal and the effect on joint strength. Each filler metal's collective tensile strength was measured, and the relationship between joint characteristics and tensile joint strength was explored. The junction was estimated through micro strength measurement, contact angle measurement with the base metal when the filler metal was melted, XRD image observation, composition analysis for each phase through SEM-EDS, and microstructure phase acquisition.

Developments of Advanced Connection Type for Improvements of Mixed Structures (II) (혼합구조의 성능 향상을 위한 개선된 접합부의 개발 (II): 개선된 접합방식의 성능확인을 위한 모형실험 및 해석)

  • Yun, Ik Jung;Lho, Byeong Cheol;Kim, Moon Kyum;Cho, Sung Young
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.28 no.2A
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    • pp.207-214
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    • 2008
  • This study presents a way to validate the quality level of the proposed connection type and verify the experimental test, and performs a 3D nonlinear analysis corresponding to the experimental test. Two mixed-structure beams were cast and tested under a four-point static loading. Force-displacement relation, force-strain relation, force-opening width, and failure mode were observed from comparing the numerical results of the adopted FE model. Nonlinear analysis of mixed structures was carried out by utilizing the contact elements of a general purpose structural analysis computer program (ABAQUS). The results of numerical and experimental simulation show that the proposed L-shaped connection has greater stiffness under flexural loading and better structural performance with regard to the connection.

An In-depth Analysis of Head-on Collision Accidents for Frontal Crash Tests of Automated Driving Vehicles (자율주행자동차 정면충돌평가방안 마련을 위한 국내 정면충돌사고 심층분석 연구)

  • Yohan Park;Wonpil Park;Seungki Kim
    • Journal of Auto-vehicle Safety Association
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    • v.15 no.4
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    • pp.88-94
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    • 2023
  • The seating postures of passengers in the automated driving vehicle are possible in atypical forms such as rear-facing and lying down. It is necessary to improve devices such as airbags and seat belts to protect occupants from injury in accidents of the automated driving vehicle, and collision safety evaluation tests must be newly developed. The purpose of this study is to define representative types of head-on collision accidents to develop collision standards for autonomous vehicles that take into account changes in driving behavior and occupants' postures. 150 frontal collision cases remained by filtering (accident videos, images, AIS 2+, passenger car, etc…) and random sampling from approximately 320,000 accidents claimed by a major insurance company over the past 5 years. The most frequent accident type is a head-on collision between a vehicle going straight and a vehicle turning left from the opposite side, accounting for 54.7% of all accidents, and most of these accidents occur in permissive left turns. The next most common frontal collision is the center-lane violation by drowsy driving and careless driving, accounting for 21.3% of the total. For the two types above, data such as vehicle speed, contact point/area, and PDOF at the moment of impact are obtained through accident reconstruction using PC-Crash. As a result, two types of autonomous vehicle crash safety test scenarios are proposed: (1) a frontal oblique collision test based on the accident types between a straight vehicle and a left-turning vehicle, and (2) a small overlap collision test based on the head-on accidents of center-lane violation.

The effect of in-situ stress parameters and metamorphism on the geomechanical and mineralogical behavior of tunnel rocks

  • Kadir Karaman
    • Geomechanics and Engineering
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    • v.37 no.3
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    • pp.213-222
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    • 2024
  • Determination of jointed rock mass properties plays a significant role in the design and construction of underground structures such as tunneling and mining. Rock mass classification systems such as Rock Mass Rating (RMR), Rock Mass Index (RMi), Rock Mass Quality (Q), and deformation modulus (Em) are determined from the jointed rock masses. However, parameters of jointed rock masses can be affected by the tunnel depth below the surface due to the effect of the in situ stresses. In addition, the geomechanical properties of rocks change due to the effect of metamorphism. Therefore, the main objective of this study is to apply correlation analysis to investigate the relationships between rock mass properties and some parameters related to the depth of the tunnel studied. For this purpose, the field work consisted of determining rock mass parameters in a tunnel alignment (~7.1 km) at varying depths from 21 m to 431 m below ground surface. At the same excavation depths, thirty-seven rock types were also sampled and tested in the laboratory. Correlations were made between vertical stress and depth, horizontal/vertical stress ratio (k) and depth, k and Em, k and RMi, k and point load index (PLI), k and Brazilian tensile strength (BTS), Em and uniaxial compressive strength (UCS), UCS and PLI, UCS and BTS. Relationships were significant (significance level=0.000) at the confidence interval of 95% (r = 0.77-0.88) between the data pairs for the rocks taken from depths greater than 166 m where the ratio of horizontal to vertical stress is between 0.6 and 1.2. The in-situ stress parameters affected rock mass properties as well as metamorphism which affected the geomechanical properties of rock materials by affecting the behavior of minerals and textures within rocks. This study revealed that in-situ stress parameters and metamorphism should be reviewed when tunnel studies are carried out.