• International Journal of Air-Conditioning and Refrigeration
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• 제17권1호
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• pp.32-36
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• 2009

The ice storage system uses water for low temperature latent heat storage. However, a refrigerator capacity is increased and COP is decreased due to supercooling of water in the course of phase change from solid to liquid. This study investigates the cooling characteristics of the TMA-water clathrate compound including TMA (Tri-methyl-amine, $(CH_3)_3N$) of $20{\sim}25wt%$ as a low temperature latent heat storage material. The results showed that the phase change temperature and the specific heat is increased and the supercooling degree is decreased as the weight concentration of TMA increased. Especially, the clathrate compound containing TMA 25 wt% has the average phase change tempera ture of $5.8^{\circ}C$, the supercooling degree of $8.0^{\circ}C$ and the specific heat of 3.499 kJ/kgK in the cooling process. This can lead to reduction of operation time of refrigerator in low temperature latent heat storage system and efficiency improvement of refrigerator COP and overall system. Therefore, energy saving and improvement of utilization efficiency are expected.

• 한국경영과학회지
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• 제31권4호
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• pp.13-33
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• 2006

Using structural equation modeling, this study empirically examined the causal relationships among the level of advanced manufacturing technology (AMT), facilitation of alignment, the degree of strategic alignment of management eccounting Information systems (MAIS), and the improvement of production performance. The causal relationships between MAIS strategic alignment and information characteristics of MAIS were also investigated. The results showed that the level of AMT has a significant and positive impact on alignment facilitation. A significant causal relationship between alignment facilitation and MAIS strategic alignment was also found. It was shown that under high degrees of MAIS strategic alignment, MAIS must provide broad-scope and integrated types of Information. The causal relation-ships between MAIS strategic alignment and organizational performance were significant and positive. Thus, it is concluded that under high levels of AMT, a high degree of MAIS strategic alignment positively contributes to the improvement of production performance.

• 품질경영학회지
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• 제27권4호
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• pp.1-19
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• 1999

This study examines the service quality management and the use of women employees for the productivity improvement in Korean service industry. Five service industries, bank, hotel, PCS(Personal Communication Service), department store, and hospital industry were chosen for this study. The results indicate that the five industries show different characteristics. It was found that department stores made the most effort to improve service quality among the five industries and that hospitals did the least effort. In the use of women employees, the proportion of women in service industry is much higher than that in the manufacturing industry, but the proportion of women in management level is still very low. Women employees do not feel high degree of sexual discrimination. But they feel unfairness in promotion and payment, and low degree of job satisfaction.

• 품질경영학회지
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• 제32권4호
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• pp.196-207
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• 2004

TDR(Tear Down & Redesign)means that renounce the past resolutely, from a white paper condition, let's change directions. That is, let's redesign from the basic of the establishment of the construction process. Through the switchover the conception, innovate totally the whole existing processes. TDR is the best core innovation activity. The ultimate aim of the TDR activity induces the employees to do more productive business and obtain excellent results in the future by solving the problems, which are the nonproductive business in the business process on the objective view, the business that customers don't recognize the value, the same old practice of business, and the unsettled business from the restriction of resources. By organizing the related to workers of those business, they can solve the problems for 3-4months by full time working This paper inquires what are the obstruction factors on the process of executing TDR activity. Through the search of the reformation plan for the improvement of immersion degree, it presents some methods to be successful business.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1996년도 한국자동제어학술회의논문집(국내학술편); 포항공과대학교, 포항; 24-26 Oct. 1996
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• pp.1040-1043
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• 1996

The accuracy of the servo control in CNC system has a great influence on the duality of machine product. Tracking performance of the servo control is deteriorated mainly by the time delay of the servo system and the inertia of the work table or bed. Contouring errors occur in every interpolation steps by the effect of the tracking performance. In this paper, $H_{\infty}$ two-degree-of-freedom(TDF) controller is designed for improvement to improve the tracking performance. The designed controller is applied 3-axis machining center model and the cutting accuracy is simulated in case of corner cutting, circular and involute interpolation. Simulation results show that $H_{\infty}$ TDF controller designed in this paper has a good effect to improve tracking performance in CNC system.

• 대한공간정보학회지
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• 제17권2호
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• pp.81-90
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• 2009

등산로는 시민들의 건강과 일상생활에 있어서 매우 중요한 역할을 하며, 여가선용의 중요한 공간이 되고 있다. 그런 측면에서 관리자는 건강증진과 야외생활에 대한 욕구를 갖고 있는 등산객을 만족시키기 위해 노력하고 있다. 본 연구에서는 휴대용GPS를 이용하여 도시 근교에 있는 등산로의 경사를 분석하고 시민의 건강증진을 위해 적합한 등산로를 제시하는데 연구 목적을 두고 있다. 그 결과 휴대용GPS에 의한 등산로 경사분석이 산책 난이도를 평가하는데 효과적임을 제시하였다.

• 한국주거학회:학술대회논문집
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• 한국주거학회 2009년 춘계학술발표대회 논문집
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• pp.332-337
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• 2009

The stronghold diffusion style method is resident participation style residential environment improvement plan that first of all, the general public constructs base facilities which the temporary occupancy public housings, commonness use facilities, roads, etc. And then with using the public housing of the stronghold sector, the resident oneself improves the house with independence or commonness. As a result induction of the voluntary participation of economic situation and the resident where the improvement will is reflected and introduction of versatile maintenance method through stronghold development with participation of the general public, this study tries to present the residential improvement method of diffusion style. San-Jun was selected in the subject of investigation area in stronghold diffusion style residential environmental improvement plan area. Investigation contents population register quality and quality of present house, the degree which is a house environmental improvement plan, about residential improvement the fact etc. Because unsatisfactorily in compliance with the deterioration and spatial narrow of the house, The above of half is an improvement intention. Hereafter residential improvement, According to the condition which is economic, residential improvement will change. The plan will be able to augment the economic enemy capability of the resident should grope and the residents oneself creates the environment will be able to improve the house. Also with creating, activating a resident organization, through autonomous decision-making process, the residential improvement could be advanced continuously.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 1999년도 봄 학술발표회 논문집
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• pp.234-241
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• 1999

In this study, an improved 8-node flat shell element is presented for the analysis of shell structure, by combining 8-node membrane element with drilling degree-of-freedom and 8-node plate bending element based on the recently presented technique. Firstly, 8-node membrane element designated as CLM8 is presented in this paper. The element has drilling degree-of.freedom in addition to transitional degree-of-freedom. Therefore the element possesses 3 degrees-of-freedom per each node which as well as the improvement of the element behavior, permits an easy connection to other element with rotational degree-of -freedom. Secondly. 8-node flat shell element was composed by adding 8-node Mindlin plate bending element to the membrane element. The behavior of the introduced plate bending element is further improved by combined use of nonconforming displacement modes, selectively reduced integration scheme and assumed shear strain fields. The element passes in the patch test, doesn't show spurious mechanism and doesn't produce shear locking phenomena. Finally, Numerical examples are presented to show the performance of flat shell element developed in the present study.

• 한국철도학회논문집
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• 제9권5호
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• pp.569-576
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• 2006

Recently, many Korean firms have been adopting $360^{\circ}$ Degree Feedback System as a way of adapting to the environmental changes in business world. The reason is that the traditional top-down way of personnel evaluation pattern can not but have many limits in this turbulent changing environment. The main purpose of this article is to depict some aspects of $360^{\circ}$ Degree Feedback System including its current status quo, its positive and negative side, and the effective ways of its improvement focusing on the railway-related "A firm".

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 2007년도 추계학술발표논문집
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• pp.21-33
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• 2007

CPAM has been applied to the paper industry for the purpose of wet-end improvement for a long time. And molecular weight and charge density have been managed most important quality factors to make CPAM for this application. Recently branched CPAM was developed to improve retention and drainage characteristics and we considered branch degree of CPAM as important factor as molecular weight and charge density. In this experiment, we tried to investigate physical and chemical properties to determine branch degree and flocculation efficiency using Arbocell pulp which was recently developed micro size pulp and finally we applied retention and drainage test under the ONP stock condition.