• Journal of National Security and Military Science
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• s.3
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• pp.73-120
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• 2005

Today's world is generation of Transformation. The Term "Transformation" is widely used in many nations and international organizations such as U.S. and NATO to describe the course of change undertaken by militaries to respond to the new and emerging security environment. Transformation involves all elements of the defense enterprise including Operational Environment, Operational Concepts, Doctrine, Structure and Technologies, within a supportive Cultures context. An Operational Environment is defined as "a composite of conditions, circumstances, and influences that affect the employment of military forces and bear on the decisions of the unit commander." The context for developing future military concept and capability lies essentially within the anticipated boundaries of the operational environment in a collective sense. The joint operational environment is essential to the nation's defense. It describes volatile, complex, and dangerous environment in which the military personnel. organizations, and material will operate. Implications coming forth from joint Operational Environment are but a starting point - many others exist. More and better Implications will come forth as people think about massages of Operational Environment, experiment its characteristics, learn to deal with its threats and scenarios, apply their experience and judgement, and then consider what is required of Korean military doctrine, organizations, training and education, material development, and leadership for operations in the joint Operational Environment.

• Journal of Korean Elementary Science Education
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• v.33 no.3
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• pp.597-606
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• 2014

The purpose of this study is to survey and analyze difficulties in teaching and learning elementary school science on the chapter titled 'electric circuit'. 28 elementary school teachers who teach 5th grade science and 73 5th grade students in elementary school were taken part in this survey. The pilot questionnaire was distributed to find out both the degree and the reason of difficulties in teaching and learning. The answers are analyzed with four areas to extract elements which make class difficult; Learner factors (L), Instruction factors (I), Curriculum & textbooks factors (C), and Environment factors (E). The results are as follows. (1) It can be seen that both students and teachers feel the highest difficulty in 7th lesson 'the direction of current', while they felt little difficulty in lesson 3 'conductor and nonconductor' and lesson 8 'the safety of electricity'. (2) The most mentioned reason of difficulties in teaching and learning was Learner factors (L). (3) Teachers felt many difficulties in experimental environment. On the other hands, students didn't think experimental failures as serious trouble. (4) Students felt many difficulties in new terms and hazy concepts or expressions. (5) Teachers felt a lot of difficulties in those from Curriculum & textbooks factors.

• Journal of The Institute of Information and Telecommunication Facilities Engineering
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• v.10 no.1
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• pp.7-13
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• 2011

Matrix multiplication is a fundamental operation of linear algebra and arises in many areas of science and engineering. This paper introduces an efficient parallel matrix multiplication scheme on N ${\times}$ N mesh-connected SIMD array processor, called multiple hierarchical SIMD architecture (HMSA). The architectural characteristic of HMSA is the hierarchically structured control units which consist of a global control unit, N local control units configured diagonally, and $N^2$ processing elements (PEs) arranged in an N ${\times}$ N array. PEs are communicating through local buses connecting four adjacent neighbor PEs in mesh-torus networks and global buses running across the rows and columns called horizontal buses and vertical buses, respectively. This architecture enables HMSA to have the features of diagonally indexed concurrent broadcast and the accessibility to either rows (row control mode) or columns (column control mode) of 2D array PEs alternately. An algorithmic mapping method is used for performance evaluation by mapping matrix multiplication on the proposed architecture. The asymptotic time complexities of them are evaluated and the result shows that paralle matrix multiplication on HMSA can provide significant performance improvement.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.3 no.3
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• pp.501-507
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• 1999

At the mobile unit for adaptation the propagation environment, it is necessity to adapt very fast the weight coefficient vector of adaptive array antenna In this paper, for the BPSK and BFSK signals with S/I=2, S/N=10 subband adaptive array signal processing method to the linear array antenna using the LMS & the Kalman filter algorithm is proposed. For the 4 elements equidistance linear array antenna systems LMS and Kalman algorithms with subband adaptive instruction principles using the subband signal processing method are adopted and the computer simulation results to the constant amplitude envelope signals such as BPSK or BFSK can be seen that the convergence characteristics of directional patterns and the signal following characteristics are more fast and stable.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.16 no.6
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• pp.556-565
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• 1991

Using the WDZ decomposition algorithm, a parallel algorithm is presented for solving the linear system Ax=b which has an nxn nonsingular tridiagonal matrix. For implementing this algorithm a CAM systolic arrary is proposed, and each processing element of this array has its own CAM to store the nonzero elements of the tridiagonal matrix. In order to evaluate this array the algorithm presented is compared to theis compared to the LU decomposition algorithm. It is found that the execution time of the algorithm presented is reduced to about 1/4 than that of the LU decomposition algorithm. If each computation process step can be dome in one time unit, the system of eqations is solved in a systolic fashion without central control is obtained in 2n+1 time steps.

• Computers and Concrete
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• v.2 no.6
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• pp.499-516
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• 2005

A composite model is used to represent the heterogeneity of plain concrete consisting of coarse aggregates, mortar matrix and the mortar-aggregate interface. The composite elements of plain concrete are modeled using triangular finite element units which have six interface nodes along the sides. Fracture is captured through a constitutive single branch softening-fracture law at the interface nodes, which bounds the elastic domain inside each triangular unit. The inelastic displacement at an interface node represents the crack opening or sliding displacement and is conjugate to the internodal force. The path-dependent softening behaviour is developed within a quasi-prescribed displacement control formulation. The crack profile is restricted to the interface boundaries of the defined mesh. No re-meshing is carried out. Solutions to the rate formulation are obtained using a mathematical programming procedure in the form of a linear complementary problem. An event by event solution strategy is adopted to eliminate solutions with simultaneous formation of softening zones in symmetric problems. The composite plain concrete model is compared to experimental results for the tensile crack growth in a Brazilian test and three-point bending tests on different sized specimens. The model is also used to simulate wedge-type shear-compression failure directly under the loading platen of a Brazilian test.

• Journal of Institute of Control, Robotics and Systems
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• v.12 no.12
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• pp.1163-1168
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• 2006

Manufacturing technology for the production of high value-added fine chemical products is emphasized and getting more attention as the diversified interests of customers and the demand of high quality products are getting bigger and bigger everyday. Thus, the development of advanced batch processes, which is the preferred and most appropriate way of producing these types of products, and the related technologies are becoming more important. Therefore, high-precision batch distillation is one of the important elements in the successful manufacturing of fine chemicals, and the importance of the process operation strategy with quality assurance cannot be overemphasized. Accordingly, proposing a process structure explanation and operation strategy of such processes including batch processes and batch distillation would be of great value. We investigate optimal operation strategy and production planning of multi-purpose plants consisting of batch processes and batch distillation for the manufacturing of fine chemical products. For the short-term scheduling of a sequential multi-purpose batch plant consisting of batch distillation under MPC and UIS policy, we proposed a MILP model based on a priori time slot allocation. Also, we consider that the waste product of being produced on batch distillation is recycled to the batch distillation unit for the saving of raw materials. The developed methodology will be especially useful for the design and optimal operations of multi-purpose and multiproduct plants that is suitable for fine chemical production.

• Nuclear Engineering and Technology
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• v.40 no.3
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• pp.183-190
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• 2008

Pyroprocessing is the optimal means of treating spent metal fuels from metal fast fuel reactors and is proposed as a potential option for GNEP in order to meet the requirements of the next generation fuel cycle. Currently, efforts for research and development are being made not only in the U.S., but also in Asian countries. Electrorefining, cathode processing by distillation, injection casting for fuel fabrication, and waste treatment must be verified by the use of genuine materials, and the engineering scale model of each device must be developed for commercial deployment. Pyroprocessing can be effectively extended to treat oxide fuels by applying an electrochemical reduction, for which various kinds of oxides are examined. A typical morphology change was observed following the electrochemical reduction, while the product composition was estimated through the process flow diagram. The products include much stronger radiation emitter than pure typical LWR Pu or weapon-grade Pu. Nevertheless, institutional measures are unavoidable to ensure proliferation-proof plant operations. The safeguard concept of a pyroprocessing plant was compared with that of a PUREX plant. The pyroprocessing is better adapted for a collocation system positioned with some reactors and a single processing facility rather than for a centralized reprocessing unit with a large scale throughput.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2005.11a
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• pp.157-162
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• 2005

It is necessary for us to research and analyze of Open Housing in order to change new housing system, because exiting multi family housing is lack of flexibility and easy remodeling. The purpose of this study is to supply and grasp basic planning and design data for flexibility of Open Housings in Korea. This study is based on the literature survey and actual investigation through visiting 17 open housing sites from 1995 to 2005 in Netherlands, Finland and Japan, which are main Open Housing. We analyzed the planning methods and elements for flexibility of open housing block and unit plan, and described the contents of analyses. We found a lot of planning and design methods-supplying option plan and user participation before occupation, various structural system for openness, common piping shaft location, slab-down and applying access flooring system, movable and demountable partition wall system etc. -applied to the open housings, and findings are applicable to the planning and designing works of apartment housings in Korea.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.33 no.3
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• pp.201-207
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• 2020

With the expansion in the use of DC power systems and increased need for system maintenance, the development of measurement devices for maintenance requires high stability. Of the different kinds of DC current measurement devices, the single-shot measurement device causes the input signal of the current measuring unit to initially generate a high inrush current. The high inrush current flows into the signal processor of the meter, shortening the life of the internal fuses and causing failure. Therefore, in this study, the I²t value for increasing the durability of the fuse is designed using the available wire diameter. Operating characteristics for 210~400% over-current of the rated current, which is relatively low over-current, are realized by the plating of low melting tin metal. As a result, a method of designing a fuse element for a DC power supply, which improves the safety of the DC current measurement device by blocking the failure caused by the inrush current, is presented.