• Journal of the Korean Vacuum Society
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• v.12 no.S1
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• pp.21-27
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• 2003

Micro-arc discharge oxidation (MDO) is a cost-effective plasma electrolytic process which can be used to improve the wear and corrosion resistance of Al-alloy parts by forming a alumina coating on the component surface. However, the MDO coated Al-alloy components often exhibit relatively high friction coefficients and low wear resistance fitted with many counterface materials, additionally, the pitting corrosion for the MDO coated AI-alloy components, especially for a thinner alumina coating, often occurs in atmosphere circumstance due to the porous alumina coats. Therefore, a duplex treatment, combining a MDO coated ahumina thin layer with a TiN coating, prepared by magnetron sputtering (MS), has been investigated. The Vicker's microhardness, pin-on-disc, electrochemical measurement, salt spray, XRD and SEM tests were used to characterize and analyze the treated samples. The work demonstrates that the MDO/MS coated samples have a combination of a very low friction coefficient and good wear resistance as well as corrosion since the micro-holes on alumina coating are partly or fully covered by TiN material.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2005.11a
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• pp.295-300
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• 2005

This Study intends to find out the subjective symptom of Construction Business Worker caused by chemical material exposure, also willing to research how much they are exposed to VOCs(Volatile Organic Compounds) and under how much harmful circumstance they are working. As the results, the job group among construction business workers which is most highly dangerous degree to be taken ill of Multiple Chemical Sensitivity is Interior Worker, next following by order of Clerical Worker, Exterior Worker. According to this result, the continuous exposure in high density must be prevented by the measures for Interior Worker also to be bestowed a compulsory break during working hour for regular exposure to the open air,

• Proceedings of the KSR Conference
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• 2008.11b
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• pp.125-131
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• 2008

This research tries to analyze and investigate the effects of the noise reduction test for the sound-absorbing materials installed tentatively on Metro Line 5. Though the noise reduction effects of each sound-absorbing material showed that there was about $2{\sim}5\;dB$ compared with before and after of the tentative installation, it shows that the noise reduction effects are reducing because of the section change condition such as dust absorption and the rail abrasion as time passes after the tentative installation. Also, many difficulties are occurring in the maintenance of the orbit facilities because of the installation of sound-absorbing materials. Though various abroad products for noise reduction are imported like this, the researches for the noise reduction effect increase for this and the improvement direction are being required because of the poor circumstance of the efficiency aspect compared to the economic investment effect because those are not suited to the character of domestic Metro.

• Advances in concrete construction
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• v.14 no.5
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• pp.309-315
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• 2022

This paper depicts the diagram of cylindrical shells as an essential idea. It centers around an outline of exploration and use of cylindrical shell in expansive current circumstance. In view of investigation of the current and prospect of model as a piece of present exploration work, a straightforward contextual analysis is examined with Love's shell theory based on Galerkin's method. The cylindrical shells are attached from one end of the cylindrical shells. The frequencies of ring support shells are investigated against the half axial wave mode. The frequencies increase on increasing the half axial wave mode. Also, the frequencies are downsized with ring supports. The software MATLAB is preferred to others because in this software computing coding is very easy to do. Just single command 'eig' furnishes shell frequencies and mode shapes by calculating eigenvalues and eigenvectors respectively. The shell vibration frequencies for cylindrical shells are compared with those results found in the open literature.

• Journal of the Korean Society for Library and Information Science
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• v.25
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• pp.265-294
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• 1993

At the present. one of the very important functions of the information center or library is to provide information service on time and to the right person. But it is impossible if the shape of the material is not complete. So it is important to keep the material of information complete. This study is on deacidification of paper materials for enhancing useful life of information. This study can be summerized as follews; The material needs deacidification is all of machine-made paper except neutral paper, and hand made paper which are below pH 6.5. The best way for the deacidification for the small amount of materals is to use aqueous deacidifiers such as Calcium Carbonate, Magnesuim Carbonate and Borax. For mass deacidification process, Methoxy Magnesuim Methyle Carbonate and Magnesuim Oxide, called

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.23
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• pp.71-91
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• 2004

The purpose of this paper is to examine the effects and problems of acceptance with modifications according to CISG Art. 19, comparing with UCC ${\S}2-207$. First of all this author raised two legal issues encountered when there is an acceptance with modifications. Scenario one is as follows : "Before either party has taken further action, there is a rise or a fall in the price of goods, was there a binding contract ?" The UCC rules provide for a contract if a purchaser sends out a purchase order and the seller sends back a sales acknowledgement form, and the items on the front(the price, description, and quantity) match up. The CISG on the other hand, is that most of the terms and conditions on the backs of the forms are important. Therefore, if they are different, there should not be a contract. Scenario two is as follows : "There has been performance, A disputes arises. What terms and conditions apply ?" The CISG and the UCC will probably lead to different results in the event the parties exchange conflicting forms and subsequently perform. Assuming that the offeree's reply contains terms that are materially different from the offer, the UCC provides that the resulting contract will include only those terms on which the writings of the parties agree, excluding conflicting terms. The CISG treats the material additions as a counter-offer and, in accordance with Art. 18, the offeree's performance may be regarded as an acceptance of a contract containing all of the offeror's terms ; or the offeror's performance may be regarded as an acceptance of a contract containing all of the offeree's terms. Second, this author raised three problems in the Art. 19 as follows ; 1) It is very difficult in practical application to decide what is material alterations even if the CISG lists material terms as an example. 2) There is a possibility for the offeror to speculate in the circumstance of market fluctuation as he has a change to object to the discrepancy in the offeree's reply. 3) There is also a possibility of inducement for the offeror or the offeree to send its own reply as a last shot.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2007.04a
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• pp.451-454
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• 2007

There is an inseparable relation between human race and engineering work. As world developed into highly industrialized society, a diversity of large structures is being built up correspondently to limited topographical circumstance. Though large structures are national establishments which provide us with convenience of life, there are some disastrous possibilities which were never predicted such as ground subsidence and degradation. It is very difficult to analyze the volume of total metamorphosis with the relative displacement measurement system which is now used and it is impossible to know whether there is structural metamorphosis within a permissible range of design or not. In this research with an object of 13-year-old earthen dam, through generating point-cloud which has 3D spatial coordinates(x, y, z) of this dam by means of 3D Laser Scanning, we can get real configuration data of slanting surface of this dam with this method of getting a number of 3D spatial coordinates(x, y, z). It gives 3D spatial model to us and we can get various information of this dam such as the distance of slanting surface of dam, dimensions and cubic volume. It can be made full use of as important source material of reinforcement and maintenance works to detect previously the bulging of the dam through this research.

• Journal of the Korean institute of surface engineering
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• v.34 no.5
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• pp.395-402
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• 2001

An induction thermal plasma system have been newly designed for advanced operation with a pulse modulated mode to control the plasma power in time domain and to create non-equilibrium effects such as fast quenching of the plasma to produce new functional materials in high rate. The system consists of MOSFET power supply with a maximum power of 50 kW with a frequency of 460 kHz, an induction plasma torch with a 10-turns coil of 80 mm diameter and 150 mm length and a vacuum chamber. The pulse modulated plasma was successfully generated at a plasma power of 30 kW and a high pressure of 100 kPa, with taking the on and off time as 10 ms, respectively. Measurements were carried out on the time-dependent spectral lines emitted from Ar species. The dynamic behavior of plasma temperature in a pulse cycle was estimated by the Boltzmann plot and the excitation temperature of Ar atom was found to be changed periodically from around 0.5 to 1.7 eV during the cycle. Two application regions of the induction thermal plasma newly generated were introduced to material processing with high rate synthesis based on non equilibrium effects, and to the finding of new arc quenching gases coming necessary for power circuit breaker, which is friendly with earth circumstance alternative to SF6 gas.

• Korean Institute of Interior Design Journal
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• no.17
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• pp.136-142
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• 1998

In early 20th Century Neo Art Movement and Fuctionalim in Europe effected to create new tendency as Modern Design and technical development through Industrial Revolution offered technical background to realize Modern Design. All these things were basic to establish 1920s and the concept as Modern Design had been established at this time in field of Architecture and design. Thubular-steel Chair which used industrial material based on social andtechnical circumstance came out as an epochal event and which symbolize Modern Design have enlarged their concept with 1920s European Dwelling Space. According to each tendency arrange characteristics as classifying on the society-cultural spatial plastic technical sides multiple dwelling house and tubular-steel chair for low income brackets have characteristic of (1) the pursuit of social functionalism design for public(socity-cultural characteristics) (2) the pursuit of simplicity based on functionalism (plastic charcteristics) (3) the standardization for mass production (technical characteristc). In conclusion the characteristics of tubular-steel chair which correspond with dwelling space in 1920's is presented a type for relation between furniture and space which correspond with formating in the formative period of Modern-design.

• IE interfaces
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• v.15 no.4
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• pp.325-337
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• 2002

In this study we consider the problem of production planning of TFT-LCD(Thin Film Transistor - Liquid Crystal Display) production factory. Due to the complexities of the TFT-LCD production processes, it is difficult to schedule the production planning, and the study about automated scheduler is insufficient. In addition, the existing production method is a Push-System to raise the operation rate with expensive equipment, that has the problem to satisfy the due-date. This study presents an algorithm having a concept of Pull-System that satisfies the due-date and considers specialties of TFT-LCD production process. We make MPS(Master Production Schedule) according to the sales order, and present algorithms for scheduling about In/Out plan considering factory capacity, line balancing, material requirement, and inventory level of all Array, Cell, and Module processes. These algorithms are integrated as an automated production system, and we implement them in the actual TFT-LCD factory circumstance.