• Korean Journal of Computational Design and Engineering
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• v.1 no.3
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• pp.242-256
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• 1996

Although feature-based design is a promising approach to fully integrating CAD/CAM, current feature-based design approaches seldom provide methodologies to easily define and design features. This paper proposes a new approach to integrating parametric design with feature-based design to overcome those limitations by globally decomposing a design into a set of features and locally defining and positioning each feature by geometric constraints. Each feature is defined as a parametric shape which consists of a feature section, attributes, and a set of constraints. The generalized sketching and sweeping techniques are used to simplify the process of designing features. The proposed approach is knowledge-based and its computational efficiency in geometric reasoning is improved greatly. Parametrically designed features not only have the advantage of allowing users to efficiently perform design changes, but also provide designers with a natural design environment in which they can do their work more naturally and creatively.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.170.1-170
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• 2001

This paper developed the model for electro hydraulic force control system by identification method via ARMAX model. Implementation of Identification is performed on Pin-On-Disk type tribotester. The wear mechanism is an important mechanic property to select a material´s life and a optimum work condition. Pin-on-disk type tribotester is popular wear analysis experimental equipment and its mechanism is that adding a force on a rotating disk to simplify two surface contact´s wear experimental condition. Material´s rotating velocity and eccentricity rotation makes disturbance and it affects adding constant force. To get a high performance of force adding part, DDV(Direct Drive Valve) which has pressure control loop is used. To obtain a tribotester´ s ARMAX model, prediction error method(PEM) is used in case force adding part and rotating part is ...

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2007.11a
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• pp.545-548
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• 2007

The 10,876 school buildings(year 2006) including elementary, junior high and high schools have been operated and the number of school buildings will increase with BTL(Build Transfer Lease) projects. However, as population is expected to decrease rapidly with low birth rate, it needs to pay more attention to managing existing school buildings. The present maintenance and management system is not being operating with regular plans but with making repairs when if problem happens. Therefore, in this study I will propose a new maintenance and management system which will improve the process of maintenance and management works and reflect the needs of related officials in charge of with analyzing a present maintenance and management system through making research into documents and questionnaires. It enables to simplify maintenance and management work, to manage budget with transparency and to make better communication between each work so that it promotes efficiency of maintenance and management work.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.10
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• pp.259-269
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• 2019

The purpose of this study is to investigate the necessity and activation plan of trial work to increase the re-employment of injured industrial workers. This study applied an internet and paper questionnaire method to 1,058 employers listed in the Korea Workers' Compensation and Welfare Services. The employers were asked about their experiences with trial work and their preferences for supports. From September 2018, the survey was conducted for 6 weeks and a total of 201 questionnaires were analyzed. Descriptive analysis and t-tests were applied. The results of the study showed that the trial work system satisfied the employers who participated in it. In order for this system to operate smoothly for injured workers, it is necessary to simplify the system's procedures, increase the amount of the trial work subsidy, and improve the amount of support after the workers convert to full time employment. In order for employers to use the new system, $750 per month will be provided for 8 months when hiring one injured worker. Eighty percent of employers stated that they would hire injured workers if the subsidy and application period are accepted. Future study and suggestions for applying the trial work system for injured industrial workers are also discussed.

• International conference on construction engineering and project management
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• 2022.06a
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• pp.1253-1253
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• 2022

Although the construction industry is changing from a 2D-based to a 3D BIM-based management process, 2D drawings are still used as standards for permits and construction. For this reason, 2D deliverables extracted from 3D BIM are one of the essential achievements of BIM projects. However, due to technical and institutional problems that exist in practice, the process of extracting 2D deliverables from BIM requires additional work beyond generating 3D BIM models. In addition, the consistency of data between 3D BIM models and 2D deliverables is low, which is a major factor hindering work productivity in practice. To solve this problem, it is necessary to build BIM data that meets information requirements (IRs) for extracting 2D deliverables to minimize the amount of work of users and maximize the utilization of BIM data. However, despite this, the additional work that occurs in the BIM process for drawing creation is still a burden on BIM users. To solve this problem, the purpose of this study is to increase the productivity of the BIM process by automating the process of extracting 2D deliverables from BIM and securing data consistency between the BIM model and 2D deliverables. For this, an expert interview was conducted, and the requirements for automation of the process of extracting 2D deliverables from BIM were analyzed. Based on the requirements, the types of drawings and drawing expression elements that require automation of drawing generation in the design development stage were derived. Finally, the method for developing automation technology targeting elements that require automation was classified and analyzed, and the process for automatically extracting BIM-based 2D deliverables through templates and rule-based automation modules were derived. At this time, the automation module was developed as an add-on to Revit software, a representative BIM authoring tool, and 120 rule-based automation rulesets, and the combinations of these rulesets were used to automatically generate 2D deliverables from BIM. Through this, it was possible to automatically create about 80% of drawing expression elements, and it was possible to simplify the user's work process compared to the existing work. Through the automation process proposed in this study, it is expected that the productivity of extracting 2D deliverables from BIM will increase, thereby increasing the practical value of BIM utilization.

• Journal of the Korean Society of Safety
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• v.33 no.4
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• pp.30-37
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• 2018

Although the safety management plan review system according to the Construction Technology Promotion Act for securing the safety of the construction work is a fundamental system essential for the prevention of the construction industry disaster, the necessity of its improvement has been raised because it often fails to meet the original purpose. In this study, through the analysis of the effect of the safety management plan and the problems of the operation, we suggest ways to improve it in view of the construction accident reduction and conducted surveys on the construction site through the questionnaires of the client, construction company, and construction business technology manager. In order to improve the effectiveness of this system as a result of the study, it is necessary to distribute the guidelines for the preparation of the safety management plan, manuals, etc., to simplify the contents of the safety management plan, also the step-by-step approval of the safety plan can be a solution. For this, it is necessary to revise the policy through consultation with the Ministry of Land, Transport and Maritime Affairs and related experts.

• Journal of Korean Academy of Nursing Administration
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• v.5 no.2
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• pp.281-295
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• 1999

The purpose of this study is to provide the basic data for the development of new pay system of hospitals by analyzing the status and problems of current pay system. The pay systems of 20 nationwide hospitals were analyzed and compared with the average pay level in Korea. In addition, the annual trend of pay system was analyzed. Based on this study, the following suggestions can be made. First, the pay levels of hospitals are, in some types of workers, lower than average. Hospitals should take much efforts to improve the payment capability through the effective management. Second, the effort to raise the proportion of basic pay to the total pay and to simplify the pay system on the basis of basic pay rather than the allowance and bonus should be made. Third, the pay system based on the length of service should be revised into the one based on work capability, achievement and performance in case of professional, clerical and managerial jobs. Fourth, the pay system determined depending on the power relationship between the labor unions and the management should be improved into the one, with which workers can feel reliable and satisfied through the revealing of the payment ability and the management improvement.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.75
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• pp.49-69
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• 2017

Making a international contract of sale is not a simple work. International Trade parties(seller and buyer) may choose trade terms such as FOB or CIF to simplify their contracts and avoid misunderstanding of international commercial practice. Incoterms is the international rules for the interpretation of the trade terms, and firstly regulated by the ICC in 1936. The latest version is Incoterms 2010. Incoterms 2010 governs certain responsibilities between the seller and the buyer under the international contract of sale. Moreover, Incoterms 2010 provides the standard of division of costs relating to contract of carriage. But we should note that Incoterms 2010 is not the part of contract of carriage. The writer points out that there is no consistence principle in distributing the special costs under the contract of carriage like unloading cost from the transport vehicle. To avoid the dispute between the parties, it is more safe for international traders to fully and completely understand on the customs and practice of carriage of goods. Incoterms 2010 provides more detailed method of delivery of goods than CISG and RAFTD. Concerning the method of delivery of goods, CISG and RAFTD simply provide that the seller shall place the goods at the discharge of buyers. The writer suggests the basic principles to allocate the special costs of delivery of goods according to the trade terms under Incoterms 2010.

• Nuclear Engineering and Technology
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• v.47 no.7
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• pp.859-866
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• 2015

The aim of this work is to investigate the transport mechanism of radioactive nuclides through the reverse osmosis (RO) membrane and to estimate its effectiveness for nuclide separation from radioactive liquid waste. An analytical model is developed to simulate the RO separation, and a series of experiments are set up to confirm its estimated separation behavior. The model is based on the extended Nernst-Plank equation, which handles the convective flux, diffusive flux, and electromigration flux under electroneutrality and zero electric current conditions. The distribution coefficient which arises due to ion interactions with the membrane material and the electric potential jump at the membrane interface are included as boundary conditions in solving the equation. A high Peclet approximation is adopted to simplify the calculation, but the effect of concentration polarization is included for a more accurate prediction of separation. Cobalt and cesium are specifically selected for the experiments in order to check the separation mechanism from liquid waste composed of various radioactive nuclides and nonradioactive substances, and the results are compared with the estimated cobalt and cesium rejections of the RO membrane using the model. Experimental and calculated results are shown to be in excellent agreement. The proposed model will be very useful for the prediction of separation behavior of various radioactive nuclides by the RO membrane.

• Journal of Power Electronics
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• v.15 no.4
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• pp.1139-1147
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• 2015

In this paper, an algorithm based on a model analysis of the online calculation of the root-mean-square (RMS) value of welding current for single-phase AC resistance spot welding (RSW) was developed. The current is highly nonlinear and typically non-sinusoidal, which makes the measuring and controlling actions difficult. Though some previous methods focused on this issue, they were so complex that they could not be effectively used in general cases. The electrical model of a single-phase AC RSW was analyzed, and then an algorithm for online calculation of the RMS value of the welding current was presented. The description includes two parts, a model-dependent part and a model-independent part. Using a previous work about online measurement of the power factor angle, the first part can be solved. For the second part, although the solution of the governing equation can be directly obtained, a lot of CPU time must be consumed due to the fact that it involves a lot of complex calculations. Therefore, a neural network was employed to simplify the calculations. Finally, experimental results and a corresponding analysis showed that the proposed algorithm can obtain the RMS values with a high precision while consuming less time when compared to directly solving the equations.