• 한국정밀공학회지
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• 제15권2호
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• pp.154-161
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• 1998

Prototypes of a design are always needed for the purpose of visualization and evaluation in the aspect of manufacturability functionality, and aesthetic appearance. Since the prototyping process requires a significant amount of cost and time, various rapid prototyping processes are recently being introduced in the process. However, it is usually necessary for a part built up by a rapid prototyping system to be refined by a post-processing process, in which the stair steps on the surfaces, the support structures (if they exist), and the unprocessed material are eliminated. This post-processing is usually done manually and is a time-consuming task. Especially, eliminating the trapped volumes, the volume of the unprocessed material entrapped by the solidified portion, is sometimes impossible in some processes. This study provides a designer with a tool to detect the existence and to calculate the quantity of the trapped volumes at the given build-up direction, so that the proper build-up direction is chosen or the part is built by pieces to avoid the problems caused by the trapped volumes in advance. Since the proposed algorithm can efficiently calculate the amount of the trapped volumes at any build-up direction, it has the potential of such application as optimizing the build-up direction to minimize the trapped volumes.

• 자원리싸이클링
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• 제5권4호
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• pp.17-24
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• 1996

The computer simulation model was established to verify the applicability of smelting reduction concept to treatment of industrial wastes which becomes issue on the enviromental and recycling view point. Computer simulation model provides as following results. The increase of post combustion ratio(PCR) and heat transfer efficiency of PC energy(HTE) is effective ways to save energy. But, in order to increase PCR, recovery efficiency of post combustion energy(HTE) have to be higher than 85% HTE considering refractory life and saving energy together. Coke is most useful fuel source because it shows lowest dependence of PCR and low hydrogen content. The quality of hot metal of current process would be expected to the similar level with that of blast furnace. The utilization of scrap and Al dross can be also possible to maximize the advantages of current process which is high temperature and chemical dilution with hot metal and slag. In case of scrap, energy consumption was slightly increases because of heating up energy of scrap. Consquently, current process concept provides the possibility of intergrating recycles of industrial wastes materials such as EAF slag, coke oven dust, life terminated acidic refractory, aluminium dross and scrap by smelting reduction process.

• 에너지공학
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• 제23권3호
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• pp.58-65
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• 2014

에너지효율등급제 사후관리의 국외 시행사례에 대해서 분석해 보았다. 이를 바탕으로 국내 사후관리제에 대한 시사점을 제시하였다. 첫째, 사후관리 위반정도가 심한 제품의 모델수 확대 및 반복적 위반업체의 해당모델에 대해 지속적으로 포함하고, 판매시장에서 구입하는 방식으로 적용되어야 할 것이다. 둘째, 사후관리 대상모델에 대한 점검결과를 반영하여 위반 발생빈도에 따라 제품별 사후관리 점검방식의 개선을 강구하는 것이 바람직하다. 셋째, 사후관리 점검결과 부적합율 또는 반복적 위반사례가 지속되는 경우 수시점검의 실시가 필요하다. 끝으로, 사후관리 점검결과에 대한 현재 관보 게재 및 보도자료 공개에서 사후관리 전과정에 대한 상세보고서까지 관계 유관기관에 공고 및 인터넷 공개로 확대하는 것이 요청된다.

• Child Health Nursing Research
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• 제26권2호
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• pp.267-276
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• 2020

Purpose: Caring for a vulnerable premature baby is a challenging task, but some mothers experience growth through that process. The purpose of this study was to investigate the factors influencing post-traumatic growth in mothers with premature infants admitted to the neonatal intensive care unit. Methods: A correlational research design was used and 105 mothers of premature infants were recruited from an online community. Data were collected from January 15 to January 25, 2019. Post-traumatic growth was measured using the Korean version of the Posttraumatic Growth Inventory. Data were analyzed using descriptive statistics, the t-test, analysis of variance, the Scheffé test, Pearson correlation coefficients, and hierarchical multiple regression. Results: The final model developed in this study explained 45.5% of post-traumatic growth (F=13.66, p<.001). Resilience (β=.54, p<.001) was the strongest predictor of post-traumatic growth, followed by the age of the mother when giving birth (β=.17, p=.028) and current employment status (β=.17, p=.049). Conclusion: For mother with premature infants to grow psychologically after their experience, it may be needed to support them to develop and strengthen their resilience through either education or their own support network.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2002년도 제24회 KOSCO SYMPOSIUM 논문집
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• pp.157-162
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• 2002

The characteristics of DeNOx conversion process by plasma/post-heating system with the simulated gas containing ethene is investigated experimentally. Without plasma treatment, $NO-NO_2$ conversion doesn't occur by $400^{\circ}C$ in a mixture of $N_2/O_2$ with a trace gas of ethene. But $NO-NO_2$ conversion occurs as temperature increases above $400^{\circ}C$. The NO can, however, be converted to $NO_2$ at lower temperatures by treating the gas mixture with non-thermal plasma. The $NO-NO_2$ conversion enhances further by passing the plasma treated gas through the post-heating furnace. Results show that 20%${\sim}50%$ more conversion of NO to $NO_2$ is observed when the temperatures of the post-heating furnace are maintained at $300^{\circ}C$ or $400^{\circ}C$. The additional $NO-NO_2$ conversion by post-heating is due to the reaction of ethene with the byproducts or radicals generated from the plasma reaction.

• 한국의료질향상학회지
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• 제24권1호
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• pp.1-8
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• 2018

Objectives: The post-accreditation management system should be systematic in order to ensure that the accredited hospital continues to strive for patient safety and quality improvement during the accreditation period. In this study, we compare the post-accreditation management system in four countries (the U.S., Australia, Japan, and Korea) and provide suggestions for improving the post-accreditation management system in Korea. Results: All four countries had the post-accreditation management system, and the basic structure of the system in Korea was similar to that of others. However, there were differences in the practical operation processes and the use of the results. In the operation process, Korea's monitoring relies on voluntary reporting by accredited hospitals. In terms of results utilization, analytical feedback to data submitted by the acrredited hospital is not provided in Korea. Conclusions: It is necessary to establish a continuous monitoring system for post-accreditation changes and provide feedback to accredited hospitals. It is also necessary to perform a survey without advance notice and establish a firm legal basis for monitoring.

• 대한물리치료과학회지
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• 제11권1호
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• pp.5-13
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• 2004

The purpose of this study was to the Pre-Post maximal exercise for analyze the Physiological Variable(Lactate, LDH, Glucose) in the runners. The subjects were 12 volunteers 6 sprinters and 6 distance runners who agreed to intention of this study. Subjects performed until possible all-out trials. Blood samples were taken from a median cubital vein Pre-Post exercise and every rest 5min during the all-out trial. The results obtained were summarized as follow ; 1) Lactate of Pre-Post exercise in treadmill test showed no significant difference between sprinters and distance runners, but showed significant in sprinters and distance respectively 2) LDH of Pre-Post exercise in treadmill test showed no significant difference between sprinters and distance runners, and that showed no significant in sprinters and distance respectively 3) Glucose of Pre-Post exercise in treadmill test showed no significant difference between sprinters and distance runners, and showed no significant in distance, but showed significant in sprinters therefor, since the runners has an intermittent characteristic which includes a frequent momentary change, it needs the fitness training that being consisted of various training, in the training method, it needs the training process which is from the whole fitness to specific fitness to improve general physical ability.

• 한국표면공학회지
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• 제48권6호
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• pp.269-274
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• 2015

In this experiment, post-nitriding treatment was performed at $400^{\circ}C$ on AISI 316 stainless steel which was plasma carburized previously at $430^{\circ}C$ for 15 hours. Plasma nitriding was implemented on AISI 316 stainless steel at various gas compositions (25% $N_2$, 50% $N_2$ and 75% $N_2$) for 4 hours. Additionally, during post nitriding Ar gas was used with $H_2$ and $N_2$ to observe the improvement of surface properties. After treatment, the behavior of the hybrid layer was investigated by optical microscopy, X-ray diffraction, and micro-hardness testing. Potentiodynamic polarization test was also used to evaluate the corrosion resistance of the samples. Meanwhile, it was found that the surface hardness increased with increasing the nitrogen gas content. Also small percentage of Ar gas was introduced in the post nitriding process which improved the hardness of the hardened layer but reduced the corrosion resistance compared with the carburized sample. The experiment revealed that AISI 316L stainless steel showed better hardness and excellent corrosion resistance compared with the carburized sample, when 75% $N_2$ gas was used during the post nitriding treatment. Also addition of Ar gas during post nitriding treatment degraded the corrosion resistance of the sample compared with the carburized sample.

• 한국세라믹학회지
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• 제46권5호
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• pp.452-455
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• 2009

A cost-effective route to synthesize $\beta$-SiAlONs from Si mixtures by reaction bonding followed by post-sintering was investigated. Three different z values, 0.45, 0.92 and 1.87, in $Si_{6-z}Al_zO_zN_{8-z}$ without excess liquid phase were selected to elucidate the mechanism of SiAlON formation and densification. For RBSN (reaction-bonded silicon nitride) specimens prior to post-sintering, nitridation rates of more than 90% were achieved by multistep heating to $1400^{\circ}C$ in flowing 5%$H_2$/95%$N_2$; residual Si was not detected by XRD analysis. An increase in density was acquired with increasing z values in post-sintered specimens, and this tendency was explained by the presence of higher amounts of transient liquid phase at larger z values. Measured z values from the synthesized $\beta$-SiAlONs were similar to the values calculated for the starting compositions. Slight deviations in z values between measurements and calculations were rationalized by a reasonable application of the characteristics of the nitriding and post-sintering processes.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제52권8호
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• pp.373-380
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• 2003

This paper consists of a study in post-assembly magnetization of LSPM (Line Start Permanent Magnet Motor). Recently, LSPM is noted as an alternative to the induction motor because it offers a very high efficiency and unity power factor, And it is necessary for permanent magnets to be magnetized by means of post-assembly magnetization in LSPMS because of the manufacturing cost involved. The manufacturing process is also simpler in post-assembly magnetization than in pre-assembly magnetization. Generally, permanent magnet motors are magnetized by their own stator coil or by magnetizing fixtures. However, the permanent magnet in a LSPM is scarcely magnetized by using them because of the eddy current of the rotor bar. Hence, it is necessary to design a magnetizing fixture that overcomes this problem. In this paper, the author analyses the post-assembly magnetization of a LSPM and proposes a method for designing the magnetizing fixture. The method that the author proposes is to make the number of coil turns greater in order to reduce the effect of the eddy current of the rotor bars.