• Clinical and Experimental Reproductive Medicine
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• 제26권1호
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• pp.117-121
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• 1999

Although anejaculation is a relatively uncommon occurrence in the general population, over 12,000 new cases are reported annually. Anejaculation may result from spinal cord injury, retroperitoneal lymph node dissection, diabetes mellitus, transverse myelitis, multiple sclerosis, or psychogenic disorders. At least 30% of men with this problem are or will be married and many will seek help to remedy their infertile state. The evolution of technique and instrumentation over the last 30 years has made electroejaculation an accessible and acceptable form of therapy. Recent successes in inducing ejaculation by means of rectal probe electrostimulation or vibratory stimulation combined with assisted reproductive techniques, such as zygote intrafallopian transfer (ZIFT), gamete intrafallopian transfer (GIFT), and in vitro fertilization (IVF), have provided these men means of producing their own biologic offspring. We have experienced a successful pregnancy with electroejaculation and in vitro fertilization in a infertile patient whose husband had an ejaculatory disturbance due to a spinal cord injury. So we report this case with a brief review of literatures.

• 문화기술의 융합
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• 제6권1호
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• pp.23-29
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• 2020

기계가 움직일 때의 동작들은 일정한 원리에 의해 움직이기 때문에 아무리 복잡하고 다양한 기계라 할지라도 기계의 운동을 지배하는 근원적 원리가 있다. 자율적 움직임은 반복을 피할 수 있고, 더 인간적이며 더 자연적인 요소에 근접하는 길이다. 복제가 아닌 독창적인 움직임은 더더욱 그러하다. 따라서 현재, 기계의 역동성은 인간의 참여에 의해 더욱 다감각적으로 표현될 수 있는 가능성에 도전하고 있으며 사실과 복제의 경계에서 그 표현영역을 점점 확대시키고 있다. 테오얀센의 작품들은 각각의 시기별로 다른 환경에 적응토록 변화하여 그의 수십 년에 걸친 연구는 초기에서 현재까지 계속 진화되고 있음을 알 수 있다. 그 진화의 초점은 무엇보다 개체를 구성하는 부품들 간의 유기적 결합이 가진 원리로부터 반복되는 원형운동과 수평적 왕복운동이라는 동일한 근원지를 가지고 있음을 알 수 있다.

• Nuclear Engineering and Technology
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• 제45권2호
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• pp.211-218
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• 2013

Large quantities of irradiated graphite waste from graphite-moderated nuclear reactors exist and are expected to increase in the case of High Temperature Reactor (HTR) deployment [1,2]. This situation indicates the need for a graphite waste management strategy. Of greatest concern for long-term disposal of irradiated graphite is carbon-14 ($^{14}C$), with a half-life of 5730 years. Fachinger et al. [2] have demonstrated that thermal treatment of irradiated graphite removes a significant fraction of the $^{14}C$, which tends to be concentrated on the graphite surface. During thermal treatment, graphite surface carbon atoms interact with naturally adsorbed oxygen complexes to create $CO_x$ gases, i.e. "gasify" graphite. The effectiveness of this process is highly dependent on the availability of adsorbed oxygen compounds. The quantity and form of adsorbed oxygen complexes in pre- and post-irradiated graphite were studied using Time of Flight Secondary Ion Mass Spectrometry (ToF-SIMS) and Xray Photoelectron Spectroscopy (XPS) in an effort to better understand the gasification process and to apply that understanding to process optimization. Adsorbed oxygen fragments were detected on both irradiated and unirradiated graphite; however, carbon-oxygen bonds were identified only on the irradiated material. This difference is likely due to a large number of carbon active sites associated with the higher lattice disorder resulting from irradiation. Results of XPS analysis also indicated the potential bonding structures of the oxygen fragments removed during surface impingement. Ester- and carboxyl-like structures were predominant among the identified oxygen-containing fragments. The indicated structures are consistent with those characterized by Fanning and Vannice [3] and later incorporated into an oxidation kinetics model by El-Genk and Tournier [4]. Based on the predicted desorption mechanisms of carbon oxides from the identified compounds, it is expected that a majority of the graphite should gasify as carbon monoxide (CO) rather than carbon dioxide ($CO_2$). Therefore, to optimize the efficiency of thermal treatment the graphite should be heated to temperatures above the surface decomposition temperature increasing the evolution of CO [4].

• 한국수자원학회논문집
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• 제44권6호
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• pp.429-438
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• 2011

In order to simulate a free surface flow in a trench channel, a three-dimensional incompressible unsteady Reynolds-averaged Navier-Stokes (RANS) equations are closed with the ${\kappa}-{\epsilon}$ model. The artificial compressibility (AC) method is used. Because the pressure fields can be coupled directly with the velocity fields, the incompressible Navier-Stokes (INS) equations can be solved for the unknown variables such as velocity components and pressure. The governing equations are discretized in a conservation form using a second order accurate finite volume method on non-staggered grids. In order to prevent the oscillatory behavior of computed solutions known as odd-even decoupling, an artificial dissipation using the flux-difference splitting upwind scheme is applied. To enhance the efficiency and robustness of the numerical algorithm, the implicit method of the Beam and Warming method is employed. The treatment of the free surface, so-called interface-tracking method, is proposed using the free surface evolution equation and the kinematic free surface boundary conditions at the free surface instead of the dynamic free surface boundary condition. AC method in this paper can be applied only to the hydrodynamic pressure using the decomposition into hydrostatic pressure and hydrodynamic pressure components. In this study, the boundary-fitted grids are used and advanced each time the free surface moved. The accuracy of our RANS solver is compared with the laboratory experimental and numerical data for a fully turbulent shallow-water trench flow. The algorithm yields practically identical velocity profiles that are in good overall agreement with the laboratory experimental measurement for the turbulent flow.

• 한국경제지리학회지
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• 제12권4호
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• pp.454-476
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• 2009

본 연구는 부산시 물류창고업의 신뢰형성 수준과 연계의 공간적 특성 간의 관계를 밝히고자 하였으며, 그 결과는 다음과 같다. 첫째, 신뢰형성 요인 중 '장기적 반복적 상호작용', '정보공유와 호혜성', '상호의존과 자산전용성'은 신뢰형성이 높은 수준인 미시적 신뢰, '근접성'과'불확실성'은 중간 수준인 중시적 신뢰, 그리고 '기업의 문화 및 규범과 공식적 제도'는 낮은 수준인 거시적 신뢰에 상대적으로 많은 영향을 미친다. 둘째, 거시적 신뢰, 중시적 신뢰, 미시적 신뢰 모두 공간적 근접성이 매우 큰 국지적 범위에서 대부분 형성되고, 신뢰형성 수준이 높을수록 연계의 공간적 범위는 국가적 범위, 국제적 범위로 확대된다. 셋째, 이러한 현상은 구매연계보다 판매연계에서, 제공하는 서비스 영역이 클수록, 수직적 연계보다 수평적 연계에서, 기업 간 관계가 발전할수록, 아웃소싱보다 공급사슬관리로 업무가 진행될 때 더욱 뚜렷하게 나타난다.

• 정보처리학회논문지D
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• 제8D권6호
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• pp.853-860
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• 2001

최근의 객체지향 소프트웨어개발에서는 설계 및 유지보수와 관련된 많은 문제점들을 해결하기 위하여 클래스를 재설계하거나 클래스계층구조를 재구성하는 등 객체지향 소프트웨어에 대한 일련의 재이용 및 재구성기법이 사용되고 있다. 본 논문에서는 클래스계층구조의 재구성에 관한 정형적인 이론을 제공함으로써 클래스계층구조의 재구성에 관하여 보다 수월하게 이해하고 적용할 수 있도록 하였다. 구체적으로 본 논문에서는 객체지향 소프트웨어의 개발에 있어서 주요 골격이 되는 클래스계층구조를 평탄화시킨 형태로 정의한 평탄화된 클래스계층구조를 소개하고, 임의의 클래스계층구조를 평탄화된 형태로 변형시키기 위한 알고리즘을 제안하였다. 클래스계층구조를 평탄화함으로써 클래스계층구조상의 계승 및 집약관계가 각 인스턴스들에게 어떻게 사상되는가를 수월하게 파악할 수 있으며, 주어진 클래스계층구조로부터 생성가능한 객체를 그대로 유지보존할 수 있는 평탄화된 형태의 새로운 클래스계층구조를 구축할 수 있다. 평탄화된 클래스계층구조는 클래스계층구조를 재구성하여 객체지향 소프트웨어를 점증적으로 변화 발전시키거나 재이용함에 있어서 기초를 제공하는 등 중요한 역할을 수행한다.

• 자원환경지질
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• 제31권2호
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• pp.149-158
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• 1998

Volcanic rocks including rhyolitic tuff, rhyolite and welded tuff in the Bupyeong silver mine area form a topographic circular structure known as a resurgent caldera. Granitic rocks are emplaced inside and outside area of the circular structure. K-Ar dating and Nd-Sr isotope studies were carried out to invesitigate the origin and petrogenetic evolution of the rhyolitic and granitic magma in the Bupeong silver mine area. Whole rock K-Ar age ranges from 208 to 131 Ma for rhyolitic rocks. Radiometric ages for the granitic rocks are 167.6 Ma for pink feldspar biotite granite from inside granitic pluton of the circular volcanic body, 178.8 Ma for the Kimpo hornblende biotite granite and 111.8 Ma for the Songdo foliated granite from outside granitic plutons of the volcanic body. The radiometric age data indicates that the volcanic activities which are partly overlapped by granite plutonic activities in the Bupyeong mine area had recorded early Jurassic and early Cretaceous in age. Initial Sr and Nd isotopic ratios of the rhyolitic rocks ($^{87}Sr/^{86}Sr$=0.710~0.719 and $^{143}Nd/^{144}Nd$=0.5115~0.5118) are similar to those of granitic rocks ($^{87}Sr/^{86}Sr$=0.709~0.716 and $^{143}Nd/^{144}Nd$=0.5115~0.5116) from inside granite stock. This means that similar source materials of felsic magma responsibles for the Bupyeong volcanic rocks and inside plutonic rocks. Based on the Nd and Sr isotopic compositions, rhyolitic and granitic magmas in the Bupyeong area originated from the partial melting of the old continental crust which has Nd model age ranging from 1500 to 2900 Ma. This is analogous to those of the other Jurassic granitoids in South Korea.

• 한국주조공학회지
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• 제40권4호
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• pp.118-127
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• 2020

Microstructural evolution during a heat treatment and high-temperature tensile properties have been investigated in conventionally cast CM247LC. In as-cast specimens, MC carbides with high amounts of Ta, Ti, Hf, and W were found to exist in the interdendritic regions, and γ' was observed in the form of cubes and octocubes prior to decomposition into cubes. In the heat-treated condition, some portion of eutectic γ-γ' remained, and uniform cubic γ' was observed in both interdendritic regions and dendrite core. Three types of carbides with different stoichiometries and compositions were found at the grain boundaries. MC carbides with high Hf contents were observed in the vicinity of eutectic γ-γ'. The highest tensile strength value was found at 750℃, whereas the greatest ductility appeared at 649℃. The effect of the temperature on the tensile properties was closely related to the dislocation structure. With increase in the test temperature, the density of dislocations inside γ' decreased, whereas that in the γ matrix increased. Stacking faults generated in γ' at 750℃ had a strengthening effect, whereas thermally activated dislocation motion at a high temperature was considered to have the opposite effect.

• 한국안전학회지
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• 제35권5호
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• pp.15-21
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• 2020

Quantitative risk assessment (QRA) is used as a legal or voluntary safety management tool for the hazardous material industry and the utilization of the method is gradually increasing. Therefore, a leak frequency analysis based on reliable generic data is a critical element in the evolution of QRA and safety technologies. The aim of this paper is to derive the leak frequency function that can be applied more flexibly in QRA based on OGP report with high reliability and global utilization. For the purpose, we first reviewed the data on the 16 equipments included in the OGP report and selected the predictors. And then we found good equations to fit the OGP data using non-linear regression analysis. The various expectation functions were applied to search for suitable parameter to serve as a meaningful reference in the future. The results of this analysis show that the best fitting parameter is found in the form of DNV function and connection function in natural logarithm. In conclusion, the average percentage error between the fitted and the original value is very small as 3 %, so the derived prediction function can be applicable in the quantitative frequency analysis. This study is to contribute to expand the applicability of QRA and advance safety engineering as providing the generic equations for practical leak frequency analysis.

• 암석학회지
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• 제28권2호
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• pp.71-83
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• 2019

사량도 지역의 화산암류는 하부로부터 윗섬안산암, 풍화리응회암, 아랫섬안산암, 오비도층, 남산유문암 그리고 사량도응회암으로 구성된다. 이 화산암류는 안산암-유문데사이트-유문암의 범위를 가지며 칼크알칼리 계열이고 조산대의 화산호환경을 지시한다. 또한 이 화산암류는 미량원소 변화도와 REE 패턴에서 각기 다른 마그마챔버에서 유래된 것으로 해석되는 세 그룹(윗섬안산암, 아랫섬안산암, 사량도응회암)으로 나뉜다. 사량도응회암은 수직 변화도에서 하부에서 상부로 갈수록 데사이트에서 유문암까지 순차적으로 보여준다(점진적으로 변화하는 화학적 조성누대). 순차적인 일련의 조성 변화는 응회암이 중심부의 유문암질 마그마를 둘러싼 상대적으로 데사이트질인 마그마로 누대된 마그마챔버의 상부에서 하부의 연속적인 분출에 의해 형성되었음을 시사한다. 누대된 마그마챔버는 분별결정작용에 의한 마그마 분화과정으로 일어난 연변 누적 및 결정 퇴적으로부터 형성되었다.