• International Journal of Quality Innovation
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• 제10권1호
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• pp.1-23
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• 2009

Face the process yield rate improvements of motherboard, although general enterprises finish deployment goal of each functions by overall quality managements, through quality improvement methods, industry engineering methods, plan-do-check-act (PDCA) methods and other improvement solutions, but it is only can be improved partially and unable to enhance the yield rate of product to the target. It only can takes one step ahead to enhance the process yield rate of motherboard with six sigma ($6{\sigma}$) overall DMAIC process and tactics. This research aimed to use six sigma quality improvement tactics by DMAIC systematic procedure and tactics, and find the key factors that effect to the process yield rate of surface mount technology. It also identified the keys input and process and output index to satisfy customer requirements and internal process index. The results showed that the major effective factors by fishbone and process failure modes and effects analysis (PFMEA). If the index of input and output that can be quantified, the optimum parameter can be found through design of experiment to ensure that the process is stable. If the factor of input and output that cannot be quantified, we found out the effective countermeasure by Mind_Mapping, make sure whole processes can be controlled stably, to reach the high product quality and enhance the customer satisfaction.

• 대한기계학회논문집A
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• 제35권10호
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• pp.1211-1222
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• 2011

일반적으로 회전체나 초기 하중 하의 구조물 또는 열변형된 파이프 등의 프리스트레스 구조물은 이러한 프리스트레스 효과로 인하여 고유진동수 및 고유진동모드가 변화되기 때문에 정확한 고유진동해석을 위해서는 프리스트레스 고유진동해석을 수행해야 한다. 시스템에 따라서는 그 복잡성으로 인하여 수십만~수백만의 큰 자유도를 갖는 대형 유한요소모델이 요구되어 이러한 대형 모델의 프리스트레스 영향을 파악하기 위한 프리스트레스 고유진동해석을 주어진 설계시간 내에 반복적으로 수행하기에는 여전히 시간적 어려움이 많은 형편이다. 따라서, 본 논문에서는 크리로프 부공간에 근거한 축소기법으로 시스템의 초기 유한요소모델에 대하여 고유진동 특성을 정확하게 나타내면서도 작은 차수의 축소모델로 표현하여 프리스트레스 고유진동해석에서의 계산시간 문제를 감소하였다. 초기 시스템과 축소 시스템의 모멘트를 일치하는 수치계산에는 아놀디 과정을 이용하였다. 적용예제로 휠과 컴프레서 임펠러를 선택하여 제안한 방법을 통한 회전에 따른 프리스트레스 고유진동해석의 정확성과 효율성을 보였다.

• 한국의류학회지
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• 제37권1호
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• pp.113-123
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• 2013

Clothes that retain and emanate body odor feel uncomfortable and unclean; subsequently, the adsorption, desorption and removal amounts of malodorous compounds from fabrics with different polarities were examined. 1-Octen-3-one, octanal and isovaleric acid, which are important malodor compounds from the body, were used as volatile organic compounds (VOC). Samples were prepared with unfinished and ${\beta}$-CD finished cotton, nylon and PET fabrics. The amounts of VOCs retained on the fabrics were measured using headspace GC-MS; in addition, the odor intensity of the samples were evaluated by 10 trained panelists. The amounts adsorbed were estimated by weight gain; however, moisture was found to have a larger effect on the increase in weight than VOCs. The polarity of the VOCs decreased in the order of isovaleric acid, octanal and 1-octen-3-one. Despite the exceptionally large amounts of octanal adsorbed on the nylon sample, the amounts of malodorous compounds adsorbed on fabrics increased with the decreasing VOC molecular weight. The unfinished PET sample adsorbed more VOCs than the unfinished-fabric samples. The odor intensity was mostly weaker in the ${\beta}$-CD finished fabrics than in the unfinished fabrics. The odor intensity of the ${\beta}$-CD finished fabrics was lower than unfinished fabrics. The amount of VOCs that remained on the soiled fabric samples after storing in air for 24 hrs decreased with the increasing VOC vapor pressure. Most VOCs were removed by washing; however, more VOCs were left on the ${\beta}$-CD finished fabrics than unfinished fabrics. The intensity of the odor from the unfinished PET and ${\beta}$-CD finished fabrics was stronger and weaker, respectively, than that of other fabrics, even when the same amounts of VOCs remained.

• 한국염색가공학회지
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• 제6권3호
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• pp.27-36
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• 1994

In order to produce a water repellent surface on polyester fabric, samples were treated in the atmosphere of $CF_4$ glow discharge plasma. The samples used in the study were ployester fabric and poyester film. The purpose of film treatment is for the comparison of hydrophobicity with fabric sample at same treatment condition. Radio frequency(13.56MHz) generator was used as electric source and its in put power is 100 Watt. Water repellency was evaluated by contact angle measurement. Result obtained are as follows. 1) Fiber interstice of original fabric was ana lysed as 0.43$\mu$m, and this value was sufficiently ideal for making water repellent fabric. 2) The most favorable setting position of substrate was the center area between two electrodes. 3) Fabric contact angle was higher than film contact angle at same treatment condition, and its difference was more than 50${\circ}$. And it was incapalbe of fabric contact angle measurement when the film contact angle was less than 90${\circ}$. because the fabric is susceptible to absorption of water by the capillary effect. 4) Fabric contact angle can not revealed the precise defferences of surface hydrophobicity, however, the film contact angle showed the real hydrophobic nature. 5) It was not sufficient method to evaluate the hydrophobicity of fabric surface by merely measure of the water contact angle. 6) It showed high water repellent nature at 0.06 torr of $CF_4$ plasma gas pressure and duration of 45 seconds treatment, and it can not be anticipated more improved nature if the pressure and duration of treatment time were increased.

• 한국작물학회지
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• 제31권2호
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• pp.220-225
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• 1986

인삼종자의 휴과타파에 온도 및 지베레린의 효과를 배 생육 단계별로 조사하였던 바 그 결과는 다음과 같다. 1. 배의 후숙초기(8월 6일~11월 6일)에는 15$^{\circ}C$, 후숙중기(개갑후 30일)에는 1$0^{\circ}C$, 후숙종기(개갑후 30일~92일)에는 5$^{\circ}C$에서 배생장이 제일 잘되었다. 2. 개갑적온은 17$^{\circ}C$ 정도로 배생장 적온(15$^{\circ}C$)보다 높았다. 3. 배의 비대생장이 완료된 종자에서는 고온 즉(25-3$0^{\circ}C$)에서 발아가 촉진되었으나 곧 부패하였다. 4. 개갑된 종자가 5$^{\circ}C$에서 105일째 80%, 1$0^{\circ}C$에서 147일째 28%의 발아율을 보였으나 15$^{\circ}C$ 이상의 온도에서는 전혀 발아되지 않았다. 5. 지베레린처리에 의해 개갑율은 증가되었으나 발아에 필요한 저온 대치효과는 인정되지 않았다. 6. 발아에 필요한 저온처리는 배의 비대생장 완료에 필요한 것으로 여겨졌다.

• 한국염색가공학회지
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• 제8권3호
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• pp.52-58
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• 1996

In order to study an applicable level for the graft finish of silk filaments and the characteristics of silk fabric, some sample fabrics were woven with grafted weft and the characteristics of sample fabrics were analyzed to evaluate the mechanical properites and the handle values according to the graft yield(%) of MMA and HEMA monomers on silk filaments. 1. The tensile properties were detected in the increase of linearity(LT) and the recovery in time of the increasing resilience(RT). 2. The bending properties were detected to have a lot of effect on the balance of bending rigidity(B) to hysteresis(2HB) according to the elastic relaxation of warp tension and the interlacing stress. 3. The shearing properities were detected to show the softness and the elastics in a case of the decrease in shearing rigidity(G) and hysteresis(2HG, 2HG5) according to the graft yields. 4. The compression properties were detected in the decrease of linearity(LC) and the uniformity of resilience(RC). It explains that the tendancies of compressible variation is not accepted. 5. The surface properities were detected to be affected by the surface forms of grafted silk filaments and the variation in the morphologies of interlacing sections. Considering the interlacing eveness, MMA grafted fabrics were accepted within the level of WOMEN'S THIN DRESS(KN-201-LDY) but HEMA grafted fabrics were not accepted. 6. The variation of handles were detected in the increase of total hand(TAV) within the levels of 65% of KOSHI and 82% of HARI on the average. 7. The handle fashions were detected in the nature of Habuta and Dechine from MAA graft but the nature of Fugi were shaped from HEMA graft in proportion to the graft yields.

• Journal of Information Processing Systems
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• 제11권3호
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• pp.370-388
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• 2015

The localization of multi-agents, such as people, animals, or robots, is a requirement to accomplish several tasks. Especially in the case of multi-robotic applications, localization is the process for determining the positions of robots and targets in an unknown environment. Many sensors like GPS, lasers, and cameras are utilized in the localization process. However, these sensors produce a large amount of computational resources to process complex algorithms, because the process requires environmental mapping. Currently, combination multi-robots or swarm robots and sensor networks, as mobile sensor nodes have been widely available in indoor and outdoor environments. They allow for a type of efficient global localization that demands a relatively low amount of computational resources and for the independence of specific environmental features. However, the inherent instability in the wireless signal does not allow for it to be directly used for very accurate position estimations and making difficulty associated with conducting the localization processes of swarm robotics system. Furthermore, these swarm systems are usually highly decentralized, which makes it hard to synthesize and access global maps, it can be decrease its flexibility. In this paper, a simple pyramid RAM-based Neural Network architecture is proposed to improve the localization process of mobile sensor nodes in indoor environments. Our approach uses the capabilities of learning and generalization to reduce the effect of incorrect information and increases the accuracy of the agent's position. The results show that by using simple pyramid RAM-base Neural Network approach, produces low computational resources, a fast response for processing every changing in environmental situation and mobile sensor nodes have the ability to finish several tasks especially in localization processes in real time.

• Tribology and Lubricants
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• 제40권2호
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• pp.47-53
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• 2024

Surface topography plays a decisive role in determining the performance of several precision components. In particular, the surface roughness of semiconductor devices affects the precision of the circuit. In this regard, the surface topography of a given surface needs to be appropriately assessed. Typically, the average roughness is used as one of the main indicators of surface finish quality because it is influenced by both dynamic and static parameters. Owing to the increasing demand for such accurate and reliable surface measurement systems, studies are continuously being conducted to understand the parameters of surface roughness and measure the average roughness with high reliability. However, the differences in the measurement methods of surface roughness are not clearly understood. Hence, in this study, the surface roughness of the back of a silicon wafer was measured using both contact and noncontact methods. Subsequently, a comparative analysis was conducted according to various surface roughness parameters to identify the differences in surface roughness depending on the measurement method. When using a 3D laser confocal microscope, even smaller surface asperities can be measured compared with the use of a 3D profiler. The results are expected to improve the understanding of the surface roughness characteristics of precision components and be used as a useful guideline for selecting the measurement method for surface topography assessment.

• 한국의료질향상학회지
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• 제2권2호
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• pp.20-30
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• 1996

Background : Theoretically as the waiting-time of patient is estimated in queueing, many men and much money are needed. But being the estimation of patient s waiting-time very important in hospital service, so the continuous monitoring of waiting-time is inevitable. To verify that the estimation of waiting-time using parking time is economical, effective and continuous monitoring method and to develop utilizing the method, this study was done. Method : In parking confirmation office, the personnel of parking office wrote parking confirm time, chart number and whether medical examination and treatment finish or not in parking ticket. The next day the parking tickets were gathered and the above data were input. The input parking data were connected with the hospital outpatient file indexing chart number. Then the patient' s data for department, new patient or not, reservation or not, receipt time and payment time were retrieved. The group for finishing medical treatment were compared with that for not finishing in average time lag between confirmation and out-time for hospital. And In-time for hospital, receipt time, payment and out-time for hospital were also analyzed. Result : Confirming parking ticket, the group for finished medical treatment left hospital after 7 minutes. This result showed that the patient for finished medical treatment left hospital immediately. So parking time was reasonable to estimation of hospital-time was concluded. The time for medical treatment, diagnosis and test was constant for all patients and short for waiting time, Then I concluded that the parking time was reasonable for estimation patient's waiting time. Overall patient's waiting time was 113 minutes and new patient's time was 149 minutes, old patient's times was 109 minutes. Waiting time for reservation patient was 98 minutes and for non reservation patient was 122 minutes. The time from hospital arrival to payment was 50 minutes for the group of reservation patient and 69 minutes for non-reservation group. The time from payment to hospital leaving was 51 minutes and 56 minutes for non reservation group. The short time difference between reserved group and not reserved group from payment to hospital leaving time was due to bottle neck effect. Conclusion : The estimation of patient's waiting time using parking time was reasonable because the possession of car was common and the time for medical treatment was equal and the patient after treatment left hospital immediately. Using this method, timely, fast evaluation and continuous monitoring of the intervention effect were possible.

• 디지털융복합연구
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• 제12권12호
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• pp.581-588
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• 2014

본 연구는 장시간 운동 시 과라나 섭취를 통하여 혈중 에너지 기질이 운동 보조수단의 한 방법으로 운동보조제(ergogenic aids)의 역할을 할 수 있는지에 대한 활용가능성을 검토하는데 목적이 있다. 본 연구를 위한 연구 대상자는 H대학교 재학 중인 중 장거리 육상 전공 남자 대학생으로 하였으며, 피험자들은 최대 심박수 기준 각 개인의 HRmax 70%의 운동 강도로 Polar(Finland)를 이용하여 60분간 트레드밀 운동을 실시하였다. 과라나 및 수분 섭취 시점은 운동 30분전, 운동시작, 20분, 40분, 운동 직후 60분으로 1회 투여량은 $200m{\ell}$씩 총 5회 섭취하도록 하였으며, 채혈은 운동 30분전, 운동 직후 60분, 회복기 30분에 걸쳐 총 3회 채혈을 하였다. 자료처리는 과라나섭취, 수분섭취와 처치시기(운동전 운동 중 휴식 시)간에 따른 반복측정에 의한 이원변량분산분석(two-way repeated ANOVA)를 실시하였다. 연구결과는 글루코스, 유리지방산, 젖산에서 수분섭취보다 과라나 섭취에서 긍정적인 영향을 미치는 것으로 확인하였다. 따라서 과라나가 운동보조제(ergogenic aids)로서의 기능을 가지고 있으며 과라나 섭취를 통해서 에너지 저장량을 증가시켜 운동수행능력을 향상시킬 것으로 사료된다.