• 한국지반공학회논문집
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• 제18권2호
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• pp.123-136
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• 2002

강우시 발생하는 여러 사면의 얕은 파괴는 지표로 침투하는 강우에 의한 포화깊이 증가에 의해 발생한다. 본 연구에서는 불포화사면 해석을 위하여 국내의 전형적인 표토층을 구성하는 화강풍화토를 3가지(SW, SP, SM)로 분류하여 함수특성곡선을 각각 구하고 그에 따른 함수특성곡선의 방정식을 추정하였으며, 기존에 사용되고 있는 Green & Ampt의 포화깊이 추정식과 수치해석 결과를 비교.분석함으로써 추정식의 사용범위에 대한 제한성을 파악하였다. 또한, 강우에 의한 사면의 포화깊이가 사면의 안정성에 미치는 영향을 파악하고 화강풍화토의 함수특성곡선을 이용하여 불포화사면의 강도정수를 추정하여 계산된 불포화지반의 해석이 기존의 포화사면의 해석에 비하여 보다 정확한 결과임을 알 수 있었다.

• 한국공작기계학회논문집
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• 제15권6호
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• pp.58-63
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• 2006

FIB equipment can perform sputtering and chemical vapor deposition simultaneously. It is very advantageously used to fabricate a micro structure part having 3D shape because the minimum beam size of ${\Phi}10nm$ and smaller is available. Since general FIB uses very short wavelength and extremely high energy, it can directly make a micro structure less than $1{\mu}m$. As a result, FIB has been probability in manufacturing high performance micro devices and high precision micro structures. Until now, FIB has been commonly used as a very powerful tool in the semiconductor industry. It is mainly used for mask repair, device correction, failure analysis, IC error correction, etc. In this paper FIB-Sputtering and FIB-CVD characteristic analysis were carried out according to $Ga^+$ ion beam current that is very important parameter for minimizing the pattern size and maximizing the yield. Also, for FIB-Sputtering burr caused by redeposition of the substrate characteristic analysis was carried out.

• Clinical and Experimental Pediatrics
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• 제58권1호
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• pp.28-32
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• 2015

Purpose: Diencephalic syndrome is an uncommon cause of failure to thrive in early childhood that is associated with central nervous system neoplasms in the hypothalamic-optic chiasmatic region. It is characterized by complex signs and symptoms related to hypothalamic dysfunction; such nonspecific clinical features may delay diagnosis of the brain tumor. In this study, we analyzed a series of cases in order to define characteristic features of diencephalic syndrome. Methods: We performed a retrospective study of 8 patients with diencephalic syndrome (age, 5-38 months). All cases had presented to Seoul National University Children's Hospital between 1995 and 2013, with the chief complaint of poor weight gain. Results: Diencephalic syndrome with central nervous system (CNS) neoplasm was identified in 8 patients. The mean age at which symptoms were noted was $18{\pm}10.5$ months, and diagnosis after symptom onset was made at the mean age of $11{\pm}9.7$ months. The mean z score was $-3.15{\pm}1.14$ for weight, $-0.12{\pm}1.05$ for height, $1.01{\pm}1.58$ for head circumference, and $-1.76{\pm}1.97$ for weight-for-height. Clinical features included failure to thrive (n=8), hydrocephalus (n=5), recurrent vomiting (n=5), strabismus (n=2), developmental delay (n=2), hyperactivity (n=1), nystagmus (n=1), and diarrhea (n=1). On follow-up evaluation, 3 patients showed improvement and remained in stable remission, 2 patients were still receiving chemotherapy, and 3 patients were discharged for palliative care. Conclusion: Diencephalic syndrome is a rare cause of failure to thrive, and diagnosis is frequently delayed. Thus, it is important to consider the possibility of a CNS neoplasm as a cause of failure to thrive and to ensure early diagnosis.

• 한국구조물진단유지관리공학회 논문집
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• 제12권1호
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• pp.101-108
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• 2008

본 연구에서는 철근과 같은 기계적 맞물림 현상을 활용하기 위하여 이형리브가 형성되어 있는 GFRP 보강근을 제작하여 철근대체 재료로 사용하기 위해 FRP 보강근의 부착성능을 규명하고자 한다. 하지만 지금까지 많은 기존 연구자들이 부착성능에 대한 실험으로 단순 1방향(수직, 수평)인장실험으로 철근과 콘크리트 또는 FRP 보강근과 콘크리트사이의 부착특성을 고찰하여 두 재료 사이의 부착-슬립에 관한 제안식을 도출해왔다. 국내에서는 아직까지 GFRP 보강근의 부착에 대한 관심이 증대대고 있는 실정이지만 피로부착에 관한연구는 미흡한 편이이어서 GFRP 보강근의 피로 연구가 필요로 하다. 본 연구에서는 BRITISH STANDARD에서 규정하고 있는 방법에 의하여 휨 부착 시험체를 제작하여 정적 휨 부착실험 최대파괴하중의 70% ~ 90%의 하중으로 반복하중재하 후 정적실험을 통하여 GFRP로 보강된 콘크리트 피로부착 성능을 검증하였다.

• 경영과정보연구
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• 제33권1호
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• pp.173-190
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• 2014

COSO(2013)보고서에 따르면 내부통제제도는 운영목적과 보고목적 및 준수목적, 세 가지 각 측면에서 기업의 목적을 달성에 대한 합리적인 확신을 제공하기 위해 설계된 절차이다. 내부회계관리제도는 이러한 세가지 통제목적 중 보고목적에 초점을 두고 있으며 자산보호 및 부정방지 프로그램을 포함한다. 따라서 취약한 내부회계관리제도를 가진 기업은 자산의 유용이나 횡령과 같은 부정이 발생할 가능성이 증가할 뿐만 아니라 부정이나 오류가 포함된 회계정보를 산출함으로써 경영자의 의사결정을 오도할 가능성이 증가하므로 기업가치에 악영향을 미칠 수 있다. 이와 관련하여 본 연구는 내부회계관리제도가 기업실패 가능성에 영향을 분석하였다. 내부회계관리제도의 특성은 내부회계관리제도의 중요한 취약점 존재여부와 운영인력 특성으로 측정하고 기업실패 가능성은 감사보고서에 기재된 계속기업불확실성으로 정의하였다. 분석결과, 기업실패 가능성은 내부회계관리제도의 취약점 존재여부와 양(+)의 관련성을 발견하였고 내부회계관리제도 운영인력의 경력및 공인회계사 자격여부와는 음(-)의 관련성을 발견하였다.

• 콘크리트학회논문집
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• 제11권6호
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• pp.113-119
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• 1999

Fatigue failure is a phenomenon such that structures under cyclic service load is failed by sudden brittle manner. Therefore, in order to obtain structures safety against the fatigue failure during their service lifes, fatigue characteristics should be considered for design and analysis of the structures. As stress range of prestressed (PS) tendons, which governs fatigus characteristic of prestressed concrete (PSC) structures, increases with increased use of partial prestressig, it is more necessary to consider fatigue characteristics of PS tendons. In this paper, direct-tension fatigue experiments with special specimen-setting devices are carried out to obtain fatigue characteristics of domestic low relaxation PS strands having different diameters and PS strands connected with coupler. Then, allowable stress range of fatigue for PSC beams using low relaxation strands are presented for the fatigue examination of prestressed concrete beams applied cyclic loading.

• 한국산업경영시스템학회:학술대회논문집
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• 한국산업경영시스템학회 2002년도 춘계학술대회
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• pp.1-8
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• 2002

At present, company has to produce a product that consumer like with a competitive price, a good quality, and a fitting time to supply. Process control and qualify control are very important to supply with a product uniformly and inexpensively In this paper, the characteristic of product quality is monitored by control chart during the machining process and construction of quality control cycle is considered to divide into two types in this case that different assignable causes lead to shifts having different magnitudes. Then we are intended to find a process shift magnitude which has economical quality cost policy and are considered to quality cost functions to find a process shift magnitude. Those costs are categorized into the well-known categories of prevention, appraisal, and internal failure and external failure. This paper ends with numerical examples that demonstrate the usefulness of the model.

• Journal of Welding and Joining
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• 제5권2호
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• pp.53-59
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• 1987

The effect of applied stress, current density and heat-treatment after welding on the time to fracture, fracture behavior was investigated by the method of constant load tensile testing under catholic charging with hydrogen in E.B. welded 250,300 Grade 18% Ni Maraging steel sheet. The main results obtained are as follows: 1. All specimen showed the characteristic delayed failure and the time to fracture showed decreasing tendency with the increase in current density and applied stress. 2. Hydrogen embitterment susceptibility of notched specimen after solution-treatment and aging after welding was more increased than that of aged smooth specimen and as welded specimen. 3. Fracture surface showed a typical intergranular fracture on the border, a dimple pattern in the center of specimen and some quasi-cleavage fracture between the intergranular and the dimple.

• 한국산업융합학회 논문집
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• 제10권3호
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• pp.149-155
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• 2007

Damage assessment and Damage index for RC members failed in flexure was investigated by using the nonlinear finite element analysis, included with nonlocal constitutive law, which is analyzed for the localization of the failure on the post-peak region. In the nonlcal constitutive law, The local strains obtained at gauss points were averaged over a particular length, i.e. characteristic length and it was used to evaluate the damage of RC column member. As the analysis results, The value of nonlocal strain shows less mesh sensibility. In the damage assessment, It was confirmed that evaluations of damage of RC member were able to use nonlocal compressive strain on a cover concrete and a core concrete of the member. Moreover it was confirmed that damage process for the statically indeterminate structure was able to evaluate the damage context of the component members of the structure.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2007년도 춘계학술대회
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• pp.569-572
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• 2007

In this paper, research about SVM(stack voltage monitoring) module is written, which studied to detect the failure mode of stack and stop stack driving. It is important role for SVM module to monitor the cell voltage and also, transfer those data to Supervisor controller. SVM module needs accurate measurement to detect failure mode, because the cell voltage is very small value under a few [V]. For improving these cost and technical efficiency, the electric characteristic experiment is made with the measurement circuit designed by using precision resistor.