• 대한기계학회논문집
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• 제19권3호
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• pp.605-614
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• 1995

In the automatic transmission using planetary gear there exists nonlinearities due to the finite difference between gear ratios, which yield torque hole during shift and influence on the ride quality and life of clutch. Based on the reaction carrier and converter turbine speed sliding functions are defined. Nonlinear closed-loop control laws are derived using them. Computer simulation shows that the closed loop design is better than the open loop design and semi-closed loop design.

• 대한음성학회:학술대회논문집
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• 대한음성학회 2003년도 5월 학술대회지
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• pp.32-35
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• 2003

This paper describes our recent work for developing a baseline platform for Korean spoken dialog recognition. In our work, We have collected about 65 hour speech corpus with auditory transcriptions. Linguistic information on various levels such as mophology, syntax, semantics, and discourse is attached to the speech database by using automatic or semi-automatic tools for tagging linguistic information.

• 대한안전경영과학회지
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• 제21권4호
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• pp.67-74
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• 2019

Visual inspection is regarded as one of the critical activities for quality control in a manufacturing company. it is thus important to improve the performance of detecting a defective part or product. There are three probable working modes for visual inspection: fully automatic (by automatic machines), fully manual (by human operators), and semi-automatic (by collaboration between human operators and automatic machines). Most of the current studies on visual inspection have been focused on the improvement of automatic detection performance by developing a better automatic machine using computer vision technologies. However, there are still a range of situations where human operators should conduct visual inspection with/without automatic machines. In this situation, human operators'performance of visual inspection is significant to the successful quality control. However, visual inspection of components assembled into a mobile camera module belongs to those situations. This study aims to investigate human performance issues in visual inspection of the components, paying more attention to human errors. For this, Abstraction Hierarchy-based work domain modeling method was applied to examine a range of direct or indirect factors related to human errors and their relationships in the visual inspection of the components. Although this study was conducted in the context of manufacturing mobile camera modules, the proposed method would be easily generalized into other industries.

• 한국군사과학기술학회지
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• 제15권1호
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• pp.9-15
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• 2012

This paper shows an effective scanning trajectory for a mine detection device that is one of the mission equipments of unmanned ground vehicle. The mine detection device is composed of a mine-detection sensor, and a 4 DOF manipulator enabling sensor position control. There are three modes that manage the mine detection device: passive, semi-automatic, and automatic. The automatic mode is used the most. This paper suggests a scanning method that makes shape of 8. This method prevents missing target area and enhances scanning speed when the mine detection device scans the ground surface in automatic mode. The suggested method is verified by simulations and experiments.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 춘계학술대회
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• pp.1355-1360
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• 2003

Currently, product of optical collimator for optical communication is depending on handiwork, and some companies are propelling semi-automatic system composite of manual and automatic operations. In this point of time, the importance of automatic system of optical collimator for optical communication is taking its place as a core technology in the development of parts with high-efficiency of optical communication. In order to develop such an optical collimator in this study, we designed an automatic assembly system, and developed a software for the system operation. At a result of that, we could carry out a single work process individually running processes of collimator fabrication, a constant work process constantly running all of the processes, and performance evaluation of the collimator.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2003년도 춘계학술대회 논문집
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• pp.1191-1194
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• 2003

At present, the fabrication of optical filter for optical communication mostly depends on handwork, and only a few companies are propelling semi-automatic systems compounded with automatic and hand-operated methods. The measurement evaluation of optical filters is not commonly useful, so it causes difficulties in the producing field. And the packaging process becomes a very unstable process because the filters are judged from the results that they are not measured and immediately packaged during that process. In this situation, the automatic assembly system of optical filter for communication is extremely important and has begun to make its appearance as the most necessary technology for developing optical communication component with high-functionality. In this paper, we constructed systems of assembly and performance evaluation for micro optical collimator. And by using that, we designed a system capable of performance evaluation and assembly of film filter of about 30 $\mu\textrm{m}$ thickness as well as optical filter for common communication.

• International Journal of Naval Architecture and Ocean Engineering
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• 제11권1호
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• pp.82-96
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• 2019

A semi-submersible structure has been widely used for offshore drilling and production of oil and gas. The small water plane area makes the structure very sensitive to weight increase in terms of payload and stability. Therefore, it is necessary to lighten the substructure from the early design stage. This study aims at an optimization of hull structure based on a sophisticated yield and buckling strength in accordance with classification rules. An in-house strength assessment system is developed to automate the procedure such as a generation of buckling panels, a collection of required panel information, automatic buckling and yield check and so on. The developed system enables an automatic yield and buckling strength check of all panels composing the hull structure at each iteration of the optimization. Design variables are plate thickness and stiffener section profiles. In order to overcome the difficulty of large number of design variables and the computational burden of FE analysis, various methods are proposed. The steepest descent method is selected as the optimization algorithm for an efficient search. For a reduction of the number of design variables and a direct application to practical design, the stiffener section variable is determined by selecting one from a pre-defined standard library. Plate thickness is also discretized at 0.5t interval. The number of FE analysis is reduced by using equations to analytically estimating the stress changes in gradient calculation and line search steps. As an endeavor to robust optimization, the number of design variables to be simultaneously optimized is divided by grouping the scantling variables by the plane. A sequential optimization is performed group by group. As a verification example, a central column of a semi-submersible structure is optimized and compared with a conventional optimization of all design variables at once.

• 한국산학기술학회논문지
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• 제22권2호
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• pp.378-385
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• 2021

매실 장아찌를 만들기 위해서는 매실 세척, 소금물 침지, 씨 및 과육 분리, 불순물 제거, 설탕 절임의 과정을 필요로 한다. 대부분의 농가에서 매실 씨 및 과육 분리 작업이 수작업으로 진행되어 이에 많은 노동력을 필요로 하며 이로 인해 매실 장아찌의 가격이 비싸다. 이를 해결하기 위해서 자동식, 반자동식 매실 씨 및 과육 분리기를 설계 및 제작하였다. 설계 과정에서 일반 매실과 소금물 침지 매실 간의 물성 비교, 매실의 자세와 칼날 종류, 형태에 따른 최대 압축력 및 회수율을 비교하였고 제작 후 현장 시험을 통해 작업성능을 파악하였다. 그 결과, 매실에 드는 힘을 최소로 하기 위해서 자동식 기계의 경우 매실을 180도로 정렬하고 6개의 역방향 칼날을 사용하였다. 그리고 반자동식 기계의 경우 매실을 180도로 정렬하고 6개의 칼날을 사용하였다. 앞선 조건에서 과육 회수율은 각각 68%, 57%의 과육 회수율이 나타났으며 작업성능은 각각 80kg/h, 62kg/h로 나타났다. 본 연구 결과를 통해 매실 장아찌 작업공정의 기계화를 통해 기존에 비해 노동력 절감이 이루어지고 이를 통해 매실 장아찌의 시장가치를 높일 수 있을 것으로 판단된다.

• 한국의류학회지
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• 제21권1호
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• pp.19-34
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• 1997

The goals of this study are to suggest the guidance for automated clothing manufacture by analysis the technology of the automated manufacturing facilities and to propose how improve the efficiency of the production planning and management for automated clothing manufacture In this study, the research about the automated clothing manufacturing machines and the analysis about the modules and functions of apparel information systems were performed. In order to understand the factory automation of the larger clothing firms, the case study method was used. The case study samples were 3 clothing firms. The results and suggestions are as follows: 1. An information technology for automated clothing manufacture has enabled the computer integrated manufacturing system to connect production planning and management part with each work station on the factory floor. 2. The apparel information system to integrate and manage manufacturing informations from each workstation and the apparel CAD system are used in the department of production planning. At the cutting room, there are automated manufacturing machines like an automatic spreading system and an automatic cutting system. Sewing room has the computer controlled unit production system and semi-automated sewing machines. In addition, in the finishing room, an automatic packing machine and a press system are used and besides a warehousing system has been developed. Considering these available technology, for better product efficiency, it is necessary to consider and utilize the specific character of these automatic manufacturing machines and computer system whether they proper to each product style. 3. Most of the clothing manufacturers are in the stage of semi-automated manufacture. In order to improve the manufacturing environment, it is needed to gradual procedure of manufacturing automation with considering the firm's financial condition, existing facilities and staffs operating machines. The case study sample firms are in the high degree of manufacturing automation. They can accomplish the flexible manufacturing system to link the information system with each work station menufacturing system by computerized control. For the case of the firm having already used the computer integrated manufacturing and managing system, it is necessary that the function to deal with drawing information is added to the retaining module of the apparel system.

• 한국산업보건학회지
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• 제17권3호
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• pp.254-260
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• 2007

Trichloroethylene(TCE) is widely used as a degreasing solvent in workplaces. TCE is primarily toxic to the nervous system, however, systemic disorder like Stevens-Johnson syndrome has been recently reported in small-scale factories, where the government has had limited information of chemical use. A survey was performed to investigate the actual condition of using TCE and to provide practical information to occupational health service agencies and professionals. This survey was carried out on 103 factories out of 430 factories which were conducted periodic work environment measurement for TCE. Degreasing was the most popular reason for using TCE in Korea, which reached to 94%. TCE was also used as a solvent for rubber in the coating or molding process, and adhesives in the bonding process. Metal fabrication was the most common as 23%, followed by assembling automobile parts (17%), and machinery (12%). Workers exposed to TCE during full-shift were 52% while 48% were exposed during short period of the shift or intermittently. Manual or semi-automatic work occupied 87% while automatic work was just 13%. Though automatic work by a closed system was generally lower exposed to TCE, compared to manual work, it can cause a high exposure when the maintenance system is improper. Semi-automatic work especially like open-top degreasing process can cause a high exposure when local exhaust system with condensing and refrigerating coils in the degreaser does not work well. In conclusion, the survey showed nationwide status of TCE exposure in various aspects. It can be used to monitor workplaces and workers exposed to TCE to prevent occupational diseases.