• 한국정밀공학회지
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• 제23권9호
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• pp.164-173
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• 2006

The cooling capacity of a micro-heat pipe is mainly governed by the magnitude of capillary pressure induced in the wick structure. For microchannel wicks, a higher capillary pressure is achievable for narrower and deeper channels. In this study, a metallic micro-heat pipe adopting high-aspect-ratio microchannel wicks is fabricated. Micromachining of high-aspect-ratio microchannels is done using the laser-induced wet etching technique in which a focused laser beam irradiates the workpiece placed in a liquid etchant along a desired channel pattern. Because of the direct writing characteristic of the laser-induced wet etching method, no mask is necessary and the fabrication procedure is relatively simple. Deep microchannels of an aspect ratio close to 10 can be readily fabricated with little heat damage of the workpiece. The laser-induced wet etching process for the fabrication of high-aspect-ratio microchannels in 0.5mm thick stainless steel foil is presented in detail. The shape and size variations of microchannels with respect to the process variables, such as laser power, scanning speed, number of scans, and etchant concentration are closely examined. Also, the fabrication of a flat micro-heat pipe based on the high-aspect-ratio microchannels is demonstrated.

• 한국정밀공학회지
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• 제22권7호
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• pp.27-37
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• 2005

Direct writing technology on the silicon wafer surface is used to reduce the size of the chip as the miniature trend in electronic circuit. In order to improve the productivity and efficiency, the real time quality estimation is very important in each semiconductor process. In laser marking, marking quality is determined by readability which is dependant on the contrast of surface, the line width, and the melting depth. Many researchers have tried to find theoretical and numerical estimation models fur groove geometry. However, these models are limited to be applied to the real system. In this study, the estimation system for the line width during the laser marking was proposed by process monitoring method. The light intensity emitted by plasma which is produced when irradiating the laser to the silicon wafer was measured using the optical sensor. Because the laser marking is too fast to measure with external sensor, we build up the coaxial monitoring system. Analysis for the correlation between the acquired signals and the line width according to the change of laser power was carried out. Also, we developed the models enabling the estimation of line width of the laser marking through the statistical regression models and may see that their estimating performances were excellent.

• 대한금속재료학회지
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• 제48권1호
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• pp.90-100
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• 2010

Micro-conductive patterns were microfabricated on an insulating substrate ($SiO_2$) surface by a selective electroless nickel plating process in order to investigate the formation of seed layers. To fabricate micro-conductive patterns, a thin layer of metal (Cu.Cr) was deposited in the desired micropattern using laser-induced forward transfer (LIFT). and above this layer, a second layer was plated by selective electroless plating. The LIFT process. which was carried out in multi-scan mode, was used to fabricate micro-conductive patterns via electroless nickel plating. This method helps to improve the deposition process for forming seed patterns on the insulating substrate surface and the electrical conductivity of the resulting patterns. This study analyzes the effect of seed pattern formation by LIFT and key parameters in electroless nickel plating during micro-conductive pattern fabrication. The effects of the process variables on the cross-sectional shape and surface quality of the deposited patterns are examined using field emission scanning electron microscopy (FE-SEM) and an optical microscope.

• The Journal of Asian Finance, Economics and Business
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• 제8권4호
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• pp.875-884
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• 2021

Competitive aggressiveness has long been believed to be the direct trigger for increased business performance, however, as a mediating variable it still needs to be further proven. This paper aims to examine the causal relationship between network capability, knowledge creation, innovativeness, competitive aggressiveness, and business performance of private universities. One model is proposed to test the role of competitive aggressiveness as a mediating variable. The population is lecturers at the 10 best private universities in East Java, Indonesia. Analysis by SEM, on 230 respondents, using random sampling method. The results show that the model is accepted, and competitive aggressiveness is proven to be a positive mediating variable in the relationship of network capability, knowledge creation, innovativeness, and business performance. The results also show that knowledge creation, and innovativeness, have an effect on competitive aggressiveness, while network capability has no effect. The research implication is that management should encourage lecturers and organizations to be more productive in conducting research and writing articles published in reputable journals, this will increase the ranking of universities. In order for the lecturers be more enthusiastic, the management gave an award to each lecturer who could submit their articles, which were then published by reputable journals.

• 대한토목학회논문집
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• 제11권1호
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• pp.45-53
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• 1991

지하구조물은 물체력과 초기응력이 지배적인 하중조건이 되며, 무한 또는 반무한영역을 경계로 한다. 또한 굴착면 주위에는 응력집중에 의해 비선형 거동이 발생한다. 본 논문에서는 경계요소법으로 물체력과 초기응력을 해석하기 위하여 영역적분은 경계 적분화하였다. 물체력에 대한 영역적분은 Galerkin텐서와 발산정리를 사용한 방법과 극좌표를 이용한 직접적분 방법으로 경계적분화하였고, 초기응력에 대한 영역적분은 극좌표를 이용한 직접적분 방법을 응용하여 경계적분화하였다. 경계요소해석 결과는 유한요소해석 결과와 비교하여 검증하였고 검증된 경계요소 프로그램을 비선형 유한요소 프로그램과 조합하여 굴착면 주위에 발생하는 비선형 거동을 합리적으로 해석하도록 하였다. 경계요소법에서 고려하기 어려운 물체력과 초기응력에 대한 영역적분을 경계적분화하여 효율적으로 해석할 수 있었으며, 조합해석 방법으로 비선형 거동을 합리적으로 해석할 수 있었다. 본 연구의 결과는 지하구조물의 해석에 유용하게 사용될 수 있을 것으로 기대된다.

• 한국산학기술학회논문지
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• 제18권5호
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• pp.475-480
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• 2017

본 논문에서는 레이저 유도증착 공정을 사용하여 절연기판위에 미세패턴의 전도성 향상시켰다. 기존의 레이저 유도증착의 공정에서 발생하는 높은 레이저빔 에너지로 인하여, 미세패턴의 낮은 증착밀도, 산화와 같은 문제점이 있다. 이러한 문제점을 폴리머 코팅층을 사용하여 증착정밀도와 전도성 향상하였다. 실리콘 웨이퍼 위에 미세패턴 증착을 위해서 크롬, 구리를 사용하였다. 본 연구에서는 다중펄스 방식의 레이저 빔을 금속박막에 조사하여 절연기판(insulating substrate: $SiO_2$) 위에 시드 층을 형성하고, 형성된 시드 층위에 무전해 도금을 적용하여 미세패턴 및 구조물을 제작하는 복합공정기술을 개발하였다. 레이저빔의 다중 스캔방식으로 조사함으로서 레이저빔의 에너지가 증착 층의 증착밀도와 표면품위를 향상시키고, 미세전극 패턴으로 사용가능한 전기 전도성을 갖게 되었음 알 수 있었다. 레이저 직접묘화법과 무전해 도금을 적용한 복합공정을 이용하여 미세전극을 증착 한 후 비저항을 측정한 결과 도금 전 저항이 $6.4{\Omega}$, 도금 후의 저항이 $2.6{\Omega}$으로 미세전극 패턴의 표면조직이 균일하고 증착되었다. 표면조직이 균일하고 치밀하게 증착되었기 때문에 전기 전도도가 약 3배정도 향상되었다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2012년도 제43회 하계 정기 학술대회 초록집
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• pp.108-109
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• 2012

This talk will begin with the demonstration of facile synthesis of silicon nanostructures using the magnesiothermic reduction on silica nanostructures prepared via self-assembly, which will be followed by the characterization results of their performance for energy storage. This talk will also report the fabrication and characterization of highly porous, stretchable, and conductive polymer nanocomposites embedded with carbon nanotubes (CNTs) for application in flexible lithium-ion batteries. It will be presented that the porous CNT-embedded PDMS nanocomposites are capable of good electrochemical performance with mechanical flexibility, suggesting these nanocomposites could be outstanding anode candidates for use in flexible lithium-ion batteries. Directed self-assembly (DSA) of block copolymers (BCPs) can generate uniform and periodic patterns within guiding templates, and has been one of the promising nanofabrication methodologies for resolving the resolution limit of optical lithography. BCP self-assembly processing is scalable and of low cost, and is well-suited for integration with existing semiconductor manufacturing techniques. This talk will introduce recent research results (of my research group) on the self-assembly of Si-containing block copolymers for the achievement of sub-10 nm resolution, fast pattern generation, transfer-printing capability onto nonplanar substrates, and device applications for nonvolatile memories. An extraordinarily facile nanofabrication approach that enables sub-10 nm resolutions through the synergic combination of nanotransfer printing (nTP) and DSA of block copolymers is also introduced. This simple printing method can be applied on oxides, metals, polymers, and non-planar substrates without pretreatments. This talk will also report the direct formation of ordered memristor nanostructures on metal and graphene electrodes by the self-assembly of Si-containing BCPs. This approach offers a practical pathway to fabricate high-density resistive memory devices without using high-cost lithography and pattern-transfer processes. Finally, this talk will present a novel approach that can relieve the power consumption issue of phase-change memories by incorporating a thin $SiO_x$ layer formed by BCP self-assembly, which locally blocks the contact between a heater electrode and a phase-change material and reduces the phase-change volume. The writing current decreases by 5 times (corresponding to a power reduction of 1/20) as the occupying area fraction of $SiO_x$ nanostructures varies.

• 임상간호연구
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• 제14권3호
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• pp.99-115
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• 2008

Purpose: The purpose for this study was to identify the present state of Clinical Nurses with Expanded Role (CNERs) and provide basic data to refine the roles of CNERs. In this study, CNREs refers to nurses who perform techniques traditionally done by doctors and use titles such as clinical nursing specialist, educator with consultation, research assistant, coordinator, physician assistant and special examiner. Method: This study was conducted from September 1 to November 12, 2007. Data from 684 nurses from 38 hospitals who responded to the questionnaire were analyzed with descriptive statistics using the SPSS 14.0 program. Results: The mean percentage of time spent was, for direct practice, 41.1%, for education and counseling, 22.8%, for consultation and coordination, 10.4%, for research, 6.8%, for administration, 8.9% and for other activities, 10.0%. The most frequently implemented CNERs, activities included consultation and education for patients and their families, counseling by telephone, history taking, physical examination, reading examination results, psychosocial assessment, managing treatment, input of prescriptions, and writing up patient records, Although not frequently performed, nurses in some fields carried out invasive procedures and prescribed medication and laboratory tests. Conclusion: Although the number of hospital CNERs are rapidly increasing, there is still confusion about the title and framework as well as standards. Furthermore, because some nurses are prescribing medication and laboratory tests as well as performing techniques not traditionally done by nurses, there is an absolute need for a legalized system and systematic education system for the safety of patients who are being cared by all CNERs.

• 간호행정학회지
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• 제1권1호
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• pp.147-211
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• 1995

Medication is a kind of medical service and a therapeutic nursing function which takes large portion of nursing service and requires complicated procedures. So many different medical personnel should be involved and cooporate each other in order to accomplish medication. Medication is also a vital nursing service, So nurse feels heavy responsibi lity in that she gives medication to the patient finally, so she has much responsibility if medication error is happened. Therefore it seems very important to clarify the problem of medication system and method, and find the subculture of medication situation because it may promote nursing productivity. The study was conducted to 1. Describe and interpret medication situation. 2. Find out the problem of medication system and method and on alternatives. 3. Compare the medication system and method of hospitals which are located in Seoul with object hospital Ethnographic methodology was used to study medication situation by doing participant observation and interview of health care personnel. Ten nurses and three nurse aids were interviewed. Two residents and internists, two phamacists and two accountants were also interviewed. Data was obtained and analized according to Developmental Research Sequence introduced by Spradly. On the basis of this data the results were as follows. 1. The overall flow of medication system was devided into six stage : first, checking doctor's order : second writing doctor's order, : third, transfering slip into the related departments such as account department, pharmacy : fourth, distribution of medication from pharmacy to unit : fifth, identifing medication by nurses : and finally, medicating to the patient. Behaviorors have been under a lot of stress in that they have to do much works, especially paperworks, So too much time were needed. They also have been suffered interpersonal conflicts among health care personnel and role conflicts in the process of doing medication service. 2. In the process of checking order, the problem was that too much time was required for checking order and paperwork. The more the order changes the more the paperwork is. Nurses have been suffering difficulties in calling internist in order to get bill. Even if writing down slip for medication order is doctor's job, Sometimes nurse has been expected to write slip by doctors or nurse would write slip beacuse of two much complexities and efforts for calling doctors. If the slip were incorrect, much time complicated procedures were more required for correcting it. So delay of administering drug would be resulted consequently. Drugs were delivered from pharmacy to units by delivery agent and phamacist. But because drugs were delivered without arranging room number of patient. Nurse should rearrange drugs in order of the room number So it had made waste time and effort, and Even when emergency drugs were needed, Prompt delivery of drug was not easy because of many reasons. For nurses, it took too long in the identification of the right drug. Actually nurses have heavy burden when medication error happens because nurse is the final actor who gives medication to the patient, So every three shift nurse ought to check drugs as soon as every shift begins. That's why it took too much time due to repeated confirming procedure. When nurses had to go patient room in order to give medications, there were difficulties in watching patient until the patient take medicine correctly. So it was impossible to check every patient wheather he took medicine or not especially in hectic situation. 3. There were many hospitals in Seoul which have similar medication system and method as object hospital according to the results of questionaire. This means that many hospitals have been suffering srimilar problems which were identified in object hospital. 4. Recommendations for promoting simplification of medication system and method were the following : Redesigning of slip from two pieces of paper into one : early discharge announcement system, and slip confirming through computer and controlling of period of prescreption from one day to two or three days : designing personal drug storage box for each patient and using it. If nurses follow the recommendations, they will make medication short & simple, and also have enough time of direct nursing care 5. Even though there were many difficulties in medicating patients. Medication itself has been considered as a caring among nurses because it makes rapport between nurse and patient. So nurses had better accept medication as a portion of nusing service not a original portion of phamacist. There are some limits in this research in terms of confining to only one unit of one hospital, and treating it especially in view of nurses' aspects, So further researchs should be continnued from various kmds of viewpoints of doctors, phamacists and so on. ${\cdot\cdot\cdot}$. Especially esthnographic study of computerized medication system and method seems to be followed.

• 한국광학회지
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• 제16권4호
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• pp.384-391
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• 2005

본 논문에서는 나노 임프린트 기술을 이용한 폴리머 링 광공진기를 제안하고 구현하였다. 공진기 역할을 하는 링 도파로에서의 전파손실과 링 및 버스 도파로 간의 광파워 결합계수를 빔전파방법을 도입하여 계산하였으며, 또한 전달 매트릭스 방법을 도입하여 이들이 소자에 미치는 영향을 분석하고 소자를 설계하였다. 특히, smoothing buffor layer를 갖는 임프린트용 스탬프를 도입하여 다음과 같은 성과를 얻을 수 있었다. 먼저 식각공정으로 얻어진 스탬프 상의 도파로 패턴의 측면 거칠기를 링 도파로의 산란손실을 개선함으로써 Q값을 획기적으로 향상시켰다. 또한, 결합영역에서 버스와 링 도파로 간의 간격을 기존 lithography 공정에서는 불가능하였던 $0.2{\mu}m$정도까지 효과적으로 줄이고 제어함으로써 링과 도파로 간의 광파워 결합을 정밀하게 조절할 수 있게 되었다. 제작된 소자의 성능을 살펴보면, 링 반경이 $200{\mu}m$인 경우에 대해 1550 nm 파장 대역에서 Q값은 ~103800이고, 소멸비는 ~11 dB, free spectral range는 1.16 nm였다.