• 반도체디스플레이기술학회지
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• 제1권1호
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• pp.15-19
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• 2002

A new vacuum packaging process in wafer level is developed for the surface micromachining devices using glass silicon anodic bonding technology. The inside pressure of the packaged device was measured indirectly by the quality factor of the mechanical resonator. The measured Q factor was about 5$\times10^4$ and the estimated inner pressure was about 1 mTorr. And it is also possible to change the inside pressure of the packaged devices from 2 Torr to 1 mTorr by varying the amount of the Ti gettering material. The long-term stability test is still on the way, but in initial characterization, the yield is about 80% and the vacuum degradation with time was not observed.

• 소성∙가공
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• 제12권2호
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• pp.116-122
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• 2003

In the Prestressed die design for cold working, many constraining conditions should be considered to insure the die safety and to improve the dimension accountancy products. Among the constraining conditions, yielding conditions, diameter ratios and interferences between rings are very important. . In this paper, therefore, flexible tolerance method was used in order to search the optimum values of design variables. The maximum inner pressure is used as objective function in this numerical analysis. In the design Process, it was also involved the safety factor to the yield strength of each ring by considering the allowable tensile or compressive hoop stress in each ring. The proposed technique has been applied to the die design of backward extrusion process, and it's analytical results have been compared with that of the conventional design method.

• 한국환경과학회지
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• 제4권3호
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• pp.259-267
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• 1995

This study was conducted to evaluate the effects of pressure and dissolved oxygen concentration on the activated slut비e and to determine the optimum depth of deep shaft process. Some results from this study were summarized as follows. 1. It is considered that low sludge product in the activated sludge system maintaining high dissolved oxygen concentration is attributed to the increase of endogeneous respiration rate caused by the increase of aerobic zone in the sludge floe. 2. The increase of dissolved oxygen concentration does not affect to the increase of organic removal efficiency greatly and therefore the limiting factor is the substrate transfer into the inner part of floe. 3. The yield coefficient, Y is decreased in proportion to the increase of oxygen concentration. In this study, Y values arre ranged from 0.70 to 0.41 according to the variation of dissolved oxygen concentration from 18.0mg/$\ell$ to 258 mg/$\ell$. 4. The optimum depth of deep shaft process should be determined within the limits of non-toxicity to the microorganism and it is about loom in this study.

• 한국전자파학회논문지
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• 제15권5호
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• pp.509-516
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• 2004

Cu 및 BCB 공정을 사용하여 고성능 RF 수동회로를 실리콘 기판 상에 구현하는 RF 수동 집적회로 공정을 개발하였다. 이러한 기술은 개별 수동소자를 통한 모듈 구현방식보다 훨씬 작고 저렴하며 우수한 성능의 RF모듈을 구현할 수 있게 하였다. 개발된 실리콘 수동 집적회로 공정으로 제작된 내경 225 um, 회전수 2.5의 인덕터는 2.7 nH의 인덕턴스를 가지며 1 ㎓ 이상에서 30 이상의 품질계수를 가지는 것으로 측정되었다. 또한 개발된 인덕터를 사용하여 WLCSP(Wafer Level Chip Scale Package) 형태의 수동회로를 제작하였다. 제작된 저역 여파기는 2차 고조파 억제를 위해 인덕터 내경 안에 병렬공진용 커패시터를 삽입하였고 2.45 ㎓에서 0.5 ㏈ 이하의 삽입손실을 보였다. 그리고 고역 여파기와 저역 여파기 구조를 가지는 발룬 회로는 2.45 ㎓에서 0.5 ㏈ 이하의 삽입손실과 182도의 출력 단자간 위상 차이를 보여주었다.

• 비파괴검사학회지
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• 제30권3호
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• pp.225-235
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• 2010

There are many types of the geometric transitions such as dent, bulge, protrusion, expansion, etc, on the inner and outer surfaces of heat exchanger tubes, steam generator tubes, and condenser tubes of nuclear power plants. Such geometric transition causes a local residual stress in heat exchanger tubes and acts as a structural factor accelerating the evolution of defects, in particular stress corrosion cracks. In the conventional eddy current test methods, the bobbin coil profilometry can provide 2-dimensional geometric information on the variation of the average inner diameter along the tube length, but the 3-dimensional distribution and the quantitative size of a local geometric transition existing in the tube cannot be measured. In this paper, a new eddy current probe, developed for the 3-dimensional profile measurement, is introduced and its superior performance is compared with that from the conventional bobbin coil profilometry for the various types of geometric transition. Also, the accuracy of the probe for the quantitative profile measurement is verified by comparing the results with that from the laser profilometry. It is expected that the new eddy current probe and techniques can be effectively used for an optimization of the tube expansion process, and the management of tubes with geometric transitions in service.

• 성인간호학회지
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• 제29권2호
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• pp.211-223
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• 2017

Purpose: This study was designed to develop and test the Hope Scale for Korean cancer patients. Methods: The process for the development of the Hope Test was a selection of initial items drawn from a literature review and in-depth interviews. The selected items were assessed for content validity by experts. The Hope Scale was comprised of five factors and 30 preliminary items. The preliminary Hope Scale for Korean Cancer Patients (HS_KCP) was administered to 259 cancer patients from one university hospital and one cancer hospital in Busan. Data were analyzed using item analysis, factor analysis, Pearson correlation coefficients, and Cronbach's ${\alpha}$. Results: Eighteen items were selected for the final scale. Five factors (inner sense of control, trust and expectation for recovery of disease, interconnection, spirituality, emotional despair) evolved from the factor analysis, which explained 63.3% of the total variance. The convergent & discriminent validity was r=.83 (p<.001), r=-73 (p<.001). The internal consistency, Cronbach's ${\alpha}$ was .88 and reliability of the subscales ranged from .54 to .85. Conclusion: The Hope Scale for Korean cancer patients demonstrated acceptable validity and reliability. It can be used to assess the hope of cancer patients and is feasible within a clinical setting.

• 한국기계가공학회지
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• 제10권2호
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• pp.67-72
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• 2011

Solvent-free paint is sprayed from higher-pressure conditions, because the viscosity is large. The hydraulic actuator which can be operated under higher-pressure condition is required to spray solvent-free paints in painting process for the environmental protection. The purpose of this paper is to develop the hydraulic actuator under higher-pressure conditions for solvent-free paint spraying system. The hydraulic actuator consists of inner spool, outer spool and ball. The analysis of a structural stability was conducted by using ANSYS V11 under the design condition of upward and downward movement of spool. As a result, the maximum von-Mises stress applied on spool under 4mm displacement showed a value of 106MPa which was greater than the allowable stress of the spool with a value of 250MPa and a value of safety factor 3. This result suggested that the spool system be unstable under the design condition so that it was necessary for the spool system to be reinforced to secure the structural stability.

• 한국항해항만학회지
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• 제32권3호
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• pp.185-192
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• 2008

본 논문의 목적은 국적외항선사들이 불확실한 국내외 해운환경변화에 적절히 대처할 수 있는 성과개선전략을 구축하는 데 있다. 이러한 목적을 위해 첫째로, 외항선사이 직면하고 있는 환경에 대처하여 성과를 개선할 수 있는 변수를 BSC의 네 관점에서 추출하여 이들 간의 관련성여부를 구조방정식 모형에 의해 분석하였다. 분석결과에 의하면, 학습 성장관점은 내부프로세스에 영향을 미치고 이는 다시 운항서비스를 제공하는 고객관점에 영향을 미치어 신규항로개발에 의한 물동량 창출, 재무적 안성성유지 및 항로수익성 제고 등의 재무적 관점요인에 영향을 미치는 것으로 인식되고 있다. 이러한 분석결과는 학습 성장관점, 내부프로세스관점 및 고객 관점과 같은 비계량적이고 비재무적변수가 외항선사의 성과개선에 기여하는 중요변수임을 시사하는 것으로 이에 대한 체계적인 관리가 필요하다.

• 한국항만경제학회지
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• 제25권4호
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• pp.299-320
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• 2009

오늘날 균형성과표(BSC)은 균형적인 관점에서 기업의 성과를 측정하고 관리하는 도구로 각광받고 있어 많은 기업이 이를 도입 적용하고 있다. 최근에는 이러한 균형성과표가 불확실한 기업상황 하에서도 적절하게 전략을 수립하고 실행하는 데에도 기여할 수 있다는 연구가 제기되어 주목받고 있다. 이에 따라 본 연구에서는 국적외항선사들이 불확실한 국내외 해운환경변화에 적절히 대처할 수 있는 전략의 수립과 실행에 균형성 과표의 유용성을 입증하여 외항선사들의 전략수행에 기여하고자 하였다. 연구결과에 의하면, 균형성과표는 해운시황변화에 대응하여 적절한 전략을 개발하고 실행하는데 유용성이 입증되어 기여하는 것으로 나타나고 있다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 춘계학술대회논문집A
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• pp.908-913
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• 2000

In the process of integrity evaluation for nuclear power plant components, a series of fracture mechanics evaluation on surface cracks in reactor pressure vessel(RPV) must be conducted. These fracture mechanics evaluations are based on stress intensity factor, K. However, under pressurized thermal shock(PTS) conditions, the combination of thermal and mechanical stress by steep temperature gradient and internal pressure causes considerably high tensile stress at the inside of RPV wall. Besides, the internal pressure during the normal operation produces high tensile stress at the RPV wall. As a result cracks on inner surface of RPVs may experience elastic-plastic behavior which can be explained with J-integral. In such a case, however, J-integral may possibly lose its validity due to constraint effect. In this paper, in order to verify the suitability of J-integral, two dimensional finite element analyses were applied for various surface crack. Total of 18 crack geometries were analyzed, and Q stresses were obtained by comparing resulting HRR stress distribution with corresponding actual stress distributions. In conclusion, HRR stress fields were found to overestimate the actual crack-tin stress field due to constraint effect.