• Title/Summary/Keyword: 기계시스템

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Comparison of the Priority of Required Capabilities of the Warrior Platform by the Types of Military Unit through AHP Analysis (AHP 분석을 통한 부대 임무유형별 워리어플랫폼 요구능력 우선순위 비교)

  • Kim, Wukki;Shin, Kyuyong;Jo, Seongsik;Baek, Seungho;Kim, Yongchul
    • Journal of Convergence for Information Technology
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    • v.11 no.6
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    • pp.262-269
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    • 2021
  • The Ministry of National Defense is re-establishing the role of the Army in accordance with the defense reform and is promoting the Warrior Platform, a next-generation individual combat system. The Warrior Platform project is divided into three stages and is being promoted. In the first stage, the quality and performance of individual items are improved, in the second stage, items between system development are integrated, and in the third stage, the combat capability is maximized by developing an integrated unit weapon system. In this paper, detailed sub-items for the five essential required competencies (survival, lethality, mobility, sustainability, Communication) that are considered for building an effective warrior platform are presented. We also present a plan that can be used to prepare a specific master plan for the Army's Warrior Platform project by using Analytic Hierarchy Process(AHP) and selecting the priority of the five required capabilities and detailed sub-items for different unit types. As a result of analyzing the priorities of the four types of units with different mission types, we find that there are differences for each unit. These results are expected to be used as useful reference materials for setting the future direction for the development of warrior platform.

Investigation on Design Aspects of the Constructed Wetlands for Agricultural Reservoirs Treatment in Korea (농업용 저수지 수질개선을 위한 국내 인공습지 설계 및 시공실태 조사)

  • Kim, Youngchul;Choi, Hyeseon;Kim, Lee-Hyung
    • Journal of Wetlands Research
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    • v.23 no.2
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    • pp.189-200
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    • 2021
  • To improve the water quality of agricultural reservoirs, constructed wetlands are applied in many places. These are technologies that establish ecosystems and important design factors include water depth distribution, inflow and outflow, water flow distribution, hydraulic residence time, water quality treatment efficiency, aspect ratio, and the distribution of open water and covered water surfaces. For high efficiency during the operation of a constructed wetland, the design needs to be optimized and this requires consideration of the different types and length of the intake dam as well as the type and connection of wetland cells. Therefore, this study was conducted to investigate and suggest factors that needs to be considered during the design and for efficient operation measures through field surveys of 23 constructed wetlands that have been established and operated in agricultural reservoirs. Results of the field investigation shows that several sites were being operated improperly due to the malfunctioning or failure of the water level sensors, sedimentation in the intake dam, and clogging of the mechanical sluice frames. In addition, it was found that as the length of the inlet channel increases, the ecological disconnection between the intake dam upstream and the wetland outlet downstream also increases and was identified as a problem. Most of the wetlands are composed of 2 to 5 cells which can result to poor hydraulic efficiency and difficulty in management if they are too large. Moreover, it was found that the flow through a small wetland can be inadequate when there are too many cells due to excessive amounts of headloss.

A Study on Loading Method of Large Scaffolding Module for LNG Carriers Using TRIZ (TRIZ를 이용한 LNG 운반선 대형 비계 모듈의 탑재 방안 연구)

  • Park, Myeong-Chul;Shin, Sang-Hoon
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.22 no.3
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    • pp.94-100
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    • 2021
  • To improve the productivity of cargo containment construction for a membrane LNG carrier, it is important to shorten the installation period and process of the scaffolding system, which is a construction workbench of a cargo containment for a membrane LNG carrier. As an effective method, opinions are being gathered to enlarge the lifting unit from the existing two stages to eight stages. On the other hand, the stresses around the pin and hole will increase significantly because of the increase in lifting load according to the large size of the module. The purpose of this study was to establish a new large module-lifting plan by introducing TRIZ to solve these problems. This study adopted a method to utilize 40 inventive principles, which is one of the various problem-solving tools of TRIZ. First, technical contradictions were derived, the engineering parameters were selected. Second, efficient inventive principles were selected to overcome the technical contradictions using a contradiction matrix. Finally, the general and specific solutions were derived through the selected inventive principle, and structural analysis confirmed that the stress generated in the structure was low. The utility of TRIZ was confirmed by the successful lifting of large modules using the established lifting method.

Development of Chicken Carcass Segmentation Algorithm using Image Processing System (영상처리 시스템을 이용한 닭 도체 부위 분할 알고리즘 개발)

  • Cho, Sung-Ho;Lee, Hyo-Jai;Hwang, Jung-Ho;Choi, Sun;Lee, Hoyoung
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.22 no.3
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    • pp.446-452
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    • 2021
  • As a higher standard for food consumption is required, the consumption of chicken meat that can satisfy the subdivided food preferences is increasing. In March 2003, the quality criteria for chicken carcasses notified by the Livestock Quality Assessment Service suggested quality grades according to fecal contamination and the size and weight of blood and bruises. On the other hand, it is too difficult for human inspection to qualify mass products, which is key to maintaining consistency for grading thousands of chicken carcasses. This paper proposed the computer vision algorithm as a non-destructive inspection, which can identify chicken carcass parts according to the detailed standards. To inspect the chicken carcasses conveyed at high speed, the image calibration was involved in providing robustness to the side effect of external lighting interference. The separation between chicken and background was achieved by a series of image processing, such as binarization based on Expectation Maximization, Erosion, and Labeling. In terms of shape analysis of chicken carcasses, the features are presented to reveal geometric information. After applying the algorithm to 78 chicken carcass samples, the algorithm was effective in segmenting chicken carcass against a background and analyzing its geometric features.

Stiffness Improvement of Timing Belt in Power Transmission (동력전달용 타이밍벨트의 강성 개선)

  • Lee, Kyeong-Yeon;Byun, Kyung-Seok
    • Journal of the Institute of Convergence Signal Processing
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    • v.23 no.1
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    • pp.1-7
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    • 2022
  • As a power transmission element, the timing belt is a toothed transmission belt that takes advantages of V-belts and gears. It has characteristics of non-slip and low noise. It is used as a power transmission device when transmitting power from a rotating shaft or linear motion in a mechanism. Rotation can be accurately transmitted through a belt pulley with grooves like a gear and a timing belt with grooves to precisely match with the belt pulley. In particular, in the mechanism in which the timing belt is used for the output shaft, the dynamic characteristics including the rigidity of the timing belt determine the transmission characteristics of the system, so its importance increases. In this paper, a stiffness reinforced belt that can be applied to a timing belt with a limited range of motion to increase its stiffness is proposed. To study the dynamic characteristics of the stiffness reinforced belt, the equation of motion for the stiffness reinforced belt was established, and a simulation model for the stiffness reinforced belt was created and analyzed. In order to confirm the analysis results of the motion equation and simulation model, a 1-axis rotation experimental equipment using a stiffness reinforcing belt was developed and the experiment was conducted. Through motion equations, simulation models, and experiment results, it was confirmed that the stiffness and dynamic characteristics of the timing belt could be improved by applying the proposed stiffness reinforcement belt.

Transfer Learning Backbone Network Model Analysis for Human Activity Classification Using Imagery (영상기반 인체행위분류를 위한 전이학습 중추네트워크모델 분석)

  • Kim, Jong-Hwan;Ryu, Junyeul
    • Journal of the Korea Society for Simulation
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    • v.31 no.1
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    • pp.11-18
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    • 2022
  • Recently, research to classify human activity using imagery has been actively conducted for the purpose of crime prevention and facility safety in public places and facilities. In order to improve the performance of human activity classification, most studies have applied deep learning based-transfer learning. However, despite the increase in the number of backbone network models that are the basis of deep learning as well as the diversification of architectures, research on finding a backbone network model suitable for the purpose of operation is insufficient due to the atmosphere of using a certain model. Thus, this study applies the transfer learning into recently developed deep learning backborn network models to build an intelligent system that classifies human activity using imagery. For this, 12 types of active and high-contact human activities based on sports, not basic human behaviors, were determined and 7,200 images were collected. After 20 epochs of transfer learning were equally applied to five backbone network models, we quantitatively analyzed them to find the best backbone network model for human activity classification in terms of learning process and resultant performance. As a result, XceptionNet model demonstrated 0.99 and 0.91 in training and validation accuracy, 0.96 and 0.91 in Top 2 accuracy and average precision, 1,566 sec in train process time and 260.4MB in model memory size. It was confirmed that the performance of XceptionNet was higher than that of other models.

Development of Korean Warrior Platform Architecture (한국형 워리어플랫폼 아키텍처 개발 연구)

  • Kim, Wukki;Shin, Kyuyong;Cho, Seongsik;Baek, Seungho;Kim, Yongchul
    • Journal of Convergence for Information Technology
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    • v.11 no.5
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    • pp.111-117
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    • 2021
  • With the rapid development of advanced science and technology including the 4th industrial revolution, the future battlefield environment is evolving at a rapid pace. In order to actively respond to issues such as reduction of military resources and shortening of service period, and to emphasize the realization of human-centered values, the Ministry of National Defense is re-establishing the role of the Army in accordance with the defense reform and is promoting the Warrior Platform, a next-generation individual combat system. In this paper, we intend to present the optimal warrior platform architecture suitable for the Korean Army by realizing the concept of future ground operations and analyzing overseas cases. We analyze the essential abilities required of individual combatants and the abilities required for each unit type, and specifically presents a plan for integration and linkage of warrior platform equipment. We also propose an efficient business promotion direction by presenting the data flow and power connection diagram between the devices that need integration and interworking.

Ground Vibration Reduction Technology Using High Damping Polymer Concrete (고 감쇠 폴리머 콘크리트를 활용한 지반진동 저감기술에 대한 연구)

  • Kim, Jeong-Jin;Seok, Won-Gyun;We, Joon-Woo;Ahn, So-Hee
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.25 no.6
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    • pp.154-160
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    • 2021
  • Recently, there have been increasing construction works carried out in urban centers, which are inducing frequent artificial vibration in the vicinity of existing structures due to such construction works. moreover, in case of industrial estates, vibration is induced due to operation of machines in the surrounding areas, thereby causing problems. meanwhile, in case of ordinary concrete that compose structure has low level of damping capability for vibration. accordingly, there are difficulties in blocking a wide range of vibrations delivered to the structures from outside including not only vibrations generated in the structures themselves but also ground vibration. recently, numerous studies are being carried out actively on high-damping system that markedly enhanced the damping performances of structures by utilizing polymer concrete in order to block the vibrations delivered to the structures through ground. therefore, this study compared the performances of polymer concrete with those of ordinary concrete, polyurethane pad and foamed rubber pad in order to review its performances in reducing ground vibration. for this purpose, review of FRF and vibration acceleration as dynamic characteristics was made. after comparative verification on the dynamic characteristics is made when polymer concrete and other aforementioned materials are applied to underground structures, the possibility of application of polymer concrete to structures is reviewed.

A Study on Injection Nozzle and Internal Flow Velocity for Removing Air Bubbles inside the Sample Tanks during Hydraulic Rupture Test (수압파열시험 시 시료 탱크 내부 기포 제거를 위한 주입 노즐 및 내부 유속 연구)

  • Yeseung, Lee;Hyunseok, Yang;Woo-Chul, Jung;Dong Hoon, Lee;Man-Sik, Kong
    • Journal of the Korean Institute of Gas
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    • v.26 no.6
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    • pp.9-15
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    • 2022
  • In order to verify the durability of the high-pressure hydrogen tank in the operating pressure range, a hydraulic rupture test should be performed. However, if the bubbles generated by the initial injection process of water are attached to the inner wall of the tank and remain, a sudden pressure change of the bubbles during the rupture of the pressurized tank may cause shock and noise. Therefore, in this study, the flow velocity required to remove the bubbles remaining on the inner wall of the tank was predicted through simplified formulas, and the shape of the injection nozzle to maintain the flow velocity was determined based on the shape of the hydrogen tank for the hydrogen bus. In addition, a numerical model was developed to predict the change in flow velocity according to the inlet pressure, and an experiment was performed through a model tank to prove the validity of the prediction result. As a result of the experiment, the flow velocity near the tank wall was similar to the predicted value of the analysis model, and when the inlet pressure was 1.5 to 5.5 bar, the minimum size of the removable bubble was predicted to be about 2.2 to 4.6 mm.

Memristors based on Al2O3/HfOx for Switching Layer Using Single-Walled Carbon Nanotubes (단일 벽 탄소 나노 튜브를 이용한 스위칭 레이어 Al2O3/HfOx 기반의 멤리스터)

  • DongJun, Jang;Min-Woo, Kwon
    • Journal of IKEEE
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    • v.26 no.4
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    • pp.633-638
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    • 2022
  • Rencently, neuromorphic systems of spiking neural networks (SNNs) that imitate the human brain have attracted attention. Neuromorphic technology has the advantage of high speed and low power consumption in cognitive applications and processing. Resistive random-access memory (RRAM) for SNNs are the most efficient structure for parallel calculation and perform the gradual switching operation of spike-timing-dependent plasticity (STDP). RRAM as synaptic device operation has low-power processing and expresses various memory states. However, the integration of RRAM device causes high switching voltage and current, resulting in high power consumption. To reduce the operation voltage of the RRAM, it is important to develop new materials of the switching layer and metal electrode. This study suggested a optimized new structure that is the Metal/Al2O3/HfOx/SWCNTs/N+silicon (MOCS) with single-walled carbon nanotubes (SWCNTs), which have excellent electrical and mechanical properties in order to lower the switching voltage. Therefore, we show an improvement in the gradual switching behavior and low-power I/V curve of SWCNTs-based memristors.