• Journal of the Korean Magnetics Society
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• v.3 no.3
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• pp.179-184
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• 1993

The X-ray diffraction pattern of amorphous $Fe_{78}Si_{9}B_{13}$ alloy was analyzed to obtain the radial distribution function (RDF) where the first peak was in the form of Gaussian function. The calculated coordination number of the form of Gaussian functiono The calculated coordination number of the sample is 13.5, the mean distance betweeon near-neighbor atoms $r_{0}$ is $2.595{\AA}$ and a Gaussian parametet ${\delta}r$ indicating near-neighbor atomic distri-bution is $0.27{\AA}$. The temperature dependence of saturated magnetization at low temperature could be explained by spin wave excitations theory yielding the spin wave stiffness constant as $117.8\;meV\;{\AA}^2$. Also, we tried to fit the observed temperature dependence of saturated magnetization with the Handrich's equation of the modified molecular field theory for the amorphous ferromagnet. Nice fittings are obtained when we used the parameters ${\Delta}=0.32$(S=1/2) and ${\Delta}=0.23$(S=1), respectively. Finally, the calculated spin wave stiffness constant using the parameters and the structural data are $149\;meV\;{\AA}^2$ for S=1/2 and $138\;meV\;{\AA}^2$ for S=1, respectively. The mean exchange coupling integral between near-neighbor atoms was estimated to be 17.9 meV for S=1/2 and 6.7 meV for S=1.

• Journal of the Korean Chemical Society
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• v.21 no.5
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• pp.339-352
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• 1977

The authors' theory developed in the preceding Paper 1 was applied to plastic deformation of ceramics, metals, alloys and single crystals. For polycrystalline substances, the flow mechanisms due to dislocation movement and grain boundary movement appear together or separately according to the experimental conditions whereas for single crystals, only the mechanism of dislocation movement appears. The parameters appearing in the flow equations $({\alpha}_{d1},\;1/{\beta}_{d1})and\;({\alpha}_{gj}/X_{gj},\;1/{\beta}_{gj})$ (j = 1 or 2), and the activation enthalpies ${\Delta}H_{k1}^{\neq}$ (k = d or g) were determined and tabulated. Here, the subscript d1 indicates the first kind of dislocation flow units and gj expresses the jth kind of grain boundary flow units. The predictions of the theory were compared with experiment with good agreement. Concerning the activation enthalpies, it was found that ${\Delta}H_{d1}^{\neq}$ 〉{\Delta}H_{g1}^{\neq}$ and that the former agrees with the activation enthalpy for bulk self-diffusion whereas the latter agrees with the activation enthalpy for grain boundary self-diffusion. These facts support the adequacy of the authors' theory which is considered as a generalized theory of plastic deformation.

• Journal of Korea Fair Competition Federation
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• no.113
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• pp.15-31
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• 2005

최근 미국의 법원은 담합을 입증하려는 시도를 주로 경제적 증거에 입각하여 분석하는 추세를 보여 왔다. 하지만 담합의 존재를 입증하는데 있어서 경제분석의 역할에도 많은 이견이 날카롭게 표출되었다. 담합의 존재에 관한 경제적 증거를 분석하는 데에 있어 유일한 합리적 근거는 최신과점이론(Modern oligopoly theory)이다. 그런데 증인으로 나선 많은 경제학자들과 법원이 최신과점이론에 자신들의 분석을 뚜렷이 기초하지 않았기 때문에, 판례법의 현 상태가 불만족스럽다고 주장하는 것이 본 논문의 핵심적 내용이다. 셔먼법 제1조는 ''계약, 결합, 공모(contract, combination, or conspiracy)에 의해 초래되는 거래(즉 경쟁)의 불합리한 제한을 규제''하는데, 이러한 계약 결합, 공모의''용어들은 합의라는 하나의 개념으로 통합하여 이해''할 수 있다. 제 1조는 다수의 당사자가 ''단일한 목적, 공통된 의도와 의견의 일치, 혹은 의사의 합치(Meeting of minds)'', 즉 ''공통된 계획에 대한 의식적 참가(consious commitment to a common scheme)''를 합의한 모든 협약을 규제한다. 셔먼법 제 1조 위반을 입증하기 위해서는 일치된 행동이 합의 하에서 일어났음을 입증해야 한다. 미국 법원은 합의를 추론할 수 있는 증거력 있는 정황증거(admissible circumstantial evidence)의 원칙을 확립하였다. 독점가격에 가까운 수준의 과점가격 설정은 ''조정되었다(coordinated)''라고 칭해지는데, 이는 ''구두 합의''와 ''암묵적 합의''의 두 가지 형태로 나뉜다. 한편, 일회게임 과점 모형과 반복게임 모형은 과점이론의 핵심을 이룬다. 과점에 대한 Chamberlin의 견해는 본래 게임과 Stigler의 모형은 그와 같은 생각의 오류를 가르쳤다. 그러나 판례법은, Petroleum products antitrust litigation사건과 reserve supply사건에서 볼 수 있듯이 종종 그러한 교훈을 망각했다. 최신과정이론과 판례를 종합해 보면, 합의의 존재에 관해 경제학자가 이끌어내는 추론과 법원이 이끌어내는 추론을 포괄하는 다음의 네 가지 일반적 원칙이 도출된다. 1. 합의가 추론되기 위해서는 상호의존성을 넘는 무언가가 먼저 제시되어야 한다. 2. 합의의 존재는 일회게임 과점 모형에서의 비협조적 내쉬균형과 일치하는 행동으로부터는 추론될 수 없다. 3. 합의의 존재는, 비록 무한반복 과점게임에서의 비협조적 내쉬균형(혹은 Chamberlin-Fellner식의 과점)과 일치하더라도, 일회게임 과점 모형에서의 비협조적 내쉬균형과 일치하지 않는 행동으로부터 추론될 수 있다. 4. 증거는 구두합의의 존재를 뒷받침해야만 한다. 이러한 원칙에서 얻을 수 있는 가장 중요한 교훈은, 합의가 존재하지 않을 경우 과점상황으로부터는 독점가격이 예상될 수 없다는 사실을 법원이 인식하는 것만으로도 합의의 추론에서 범하기 쉬운 가장 큰 오류를 회피할 수 있다는 것이다.

• Korean Journal of Optics and Photonics
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• v.6 no.1
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• pp.26-32
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• 1995

A Kerr cell was utilized as an optical shutter to generate a shortened pulse and as an isolator between amplifiers in an iodine laser system. By rotating the polarization of incident laser pulse only during the timing window of high voltage applied to the Kerr cell, shortened pulses of 5 ns and 1 ns, corresponding to the difference in propagation time of two coaxial cables, were obtained. It was also noticed that more than one timing window of Kerr cell was produced with a long incident laser pulse from the oscillator. The measured transmittance of Kerr cell with respect to applied voltage was compared with the theoretical estimation using the electro-optic Kerr effect theory. Through the amplification of the shortened pulse in iodine amplifiers. a pulse of 0.5 GW(2 J in 4 ns) was obtained. ained.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.25 no.2
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• pp.289-295
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• 2001

The aim of this study is to investigate the ductile fracture behaviour under pure Mode II loading using A533B pressure vessel steel. Single punch shear(SPS) test was performed to obtain the J-R curve under pure Mode II loading which was compared with that of the Model I loading. Simulation using Rousellier Ductile Damage Theory(RDDT) was carried out with 4-node quadrilateral element(L(sub)c=0.25mm). For the crack advance, the failed element removal technique was adopted with a $\beta$ criterion. Through the $\beta$ value tuning-up procedures, $\beta$(sub)crit(sup)II was determined as 1.5 in contrast with $\beta$(sub)crit(sup)I=5.5. In conclusion, it was found that the J-R curve under Mode II loading was located at lower part than that under Mode I loading obtained from the previous study and that the $\beta$ values strongly depended on the loading type. In addition, the predicted result using RDDT showed a good agreement with the SPS experimental one under pure Mode II loading.

• Journal of the Korean Society for Railway
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• v.12 no.5
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• pp.719-724
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• 2009

In this study, DCB(double cantilever beam) specimens of woven fabric carbon/epoxy and glass/epoxy were manufactured and mode I fracture toughness of specimen was measured according to ASTM 5528-01. And FE analysis was conducted in the same condition and evaluated the behavior of delamination analytically. Mode I fracture toughness measured by test was $845.7\;J/m^2$ in the case carbon/epoxy and that of glass/epoxy was $1,042\;J/m^2$. FE analysis was conducted using cohesive elements for adhesive layer and applied measured fracture toughness. To verify the result of analysis, the reaction force measured at the end of specimen and that calculated by Timoshenko beam theory were compared. The numerical results show good agreements with the measured one.

• Journal of KIISE:Computer Systems and Theory
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• v.37 no.4
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• pp.205-214
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• 2010

BPEL is a standard workflow language, which interacts with Web Services and is used in various applications. But it is difficult to use BPEL for specific applications which require additional functions. In this paper, we present a system which can add new functions to BPEL based on an aspect-oriented programming (AOP) technique. In order to add new functions to BPEL, we define a JWX document format that can describe new functions to apply to BPEL. JWX is XML-oriented document that can code the corresponding Java program in order to dynamically add new functions to BPEL documents. It is possible for BPEL workflow to add new functions without modifying the existing programs using the AOP technique, which guarantees low degree of coupling between key and additional requirements. Additionally this systems weaves based on new functions of Java program and JWX document by expanding BPEL engine called B2J based on AOP and execute them. Therefore it is possible to develop a new BPEL engine with additional functions easily and with low cost. The new system can execute additional conditions that the current BPEL engine doesn’t provide. The new system using functions of BPEL supplied by B2J. The new system can be used to add a new rule engine, which isn't currently provided.

• Applied Chemistry for Engineering
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• v.9 no.7
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• pp.974-978
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• 1998

The kinetics of crystal growth and nucleation in dependence on the supersaturation of an aqueous solution of 3-nitro-1,2,4-triazol-5-one(NTO) were evaluated on the draft tube-baffle(DTB) crystallizer operated batchwise. The crystal growth rate is proportional to the supersaturation to the 2.9 power, and the nucleation rate to the 4.2 power. The uncleation behavior for NTO-water system in DTB crystallizer was grasped according to Mersmann's criteria. The nucleation in this crystallizer was found to act with heterogeneous nucleation and surface uncleation simultaneously. Simplified relation was derived for calculation of mean crystal size of product crystals from the batch cooling crystallizer. The obtained relation was verified by a set of experiments.

• Information Systems Review
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• v.22 no.2
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• pp.101-120
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• 2020

This study investigates the effects of privacy psychological characteristics of B2C logistics services users on their willingness to comply with their logistics companies' information protection policy. Using cognitive valence theory as a theoretical framework, this study proposes a research model to examine the relationships between users' logistics security knowledge, privacy trust, privacy risk, privacy concern, and their willingness of information protection policy compliance. To test the proposed model, we conducted a survey from actual users of logistics services and collected valid 151 samples. We analyzed the data using a structural equation modeling software. The empirical results show that logistics security knowledge positively affects privacy trust; privacy concern positively influences privacy risk; privacy trust, privacy risk, and privacy concern positively influence behavioral willingness of compliance. However, logistics security knowledge does not affect behavioral willingness of compliance. The results of the study provide several contributions to the literature of B2C logistics services domain and managerial implications to logistics services companies.

• Journal of the Society of Naval Architects of Korea
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• v.36 no.4
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• pp.128-136
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• 1999

This paper suggests a new object-oriented methodology, ESBD(Evolutionary Simulation Based Design), for the development of an automated manufacturing system in shipbuilding. The target system, AHMS(Automated Hull-piece Manufacturing System), is a virtualized and distributed system controlling the manufacturing processes of storing, surface-pretreatment, cutting, 1st and 2nd curvature generation of material plates. The control and product-flow simulation is applied for the real-time product monitoring and product data management(PDM). The prototype system of AHMS also outlines the layout of the new automated factory.