• Journal of the Korean Society of Manufacturing Process Engineers
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• 제2권4호
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• pp.40-45
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• 2003

In this paper, to choose the optimum CBN wheel for Internal Grinding at LM Guide, among 7 types of CBN-wheels, the 2 types of CBN-wheels, which were the macrofracture CBN wheel and the microfracture CBN wheel, have been used, and the SCM420H have been used as the workpiece. The working conditions in the grinding experiments were depth-of-cut, table speed, and spindle speed for 4 types of the CBN grinding wheels, 2 types of the lubrications. By the experiments, the loading effect of the microfracture types of the CBN-wheel needed a short dressing interval and resulted in grinding wheel wear and bad surface roughness. However, a macrofracture type of CBN-wheel with the concentration of 100, CB120Q100V showed the best surface roughness quality at a low table speed for internal grinding at LM-guide.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• 제20권6호
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• pp.817-823
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• 2011

This paper proposes a cooling stop temperature control(CST) and a phase transformation control(PTR) which aim at obtaining the uniform temperature and quality along the longitudinal direction of the high strength steel on the run-out table(ROT) process. The problems of the temperature control are analyzed for the conventional steel and the new control concepts are derived from a time-temperature transformation(TTT) diagram. The proposed control technologies are verified from the simulation results under the temperature prediction model by the heat transfer governing equation, and the temperature estimation simulator. It is shown through the field test of the hot strip mills that the phase transformation ratio of the high strength steel is considerably improved by the proposed temperature controls.

• Journal of Biosystems Engineering
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• 제35권2호
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• pp.138-145
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• 2010

An on-line algorithm that discriminates brown rice kernels on their echelon feeder using color image processing is presented for quality inspection. A rapid color image segmentation algorithm based on Bayesian clustering method was developed by means of the look-up table which was made from the significant clusters selected by experts. A robust estimation method was presented to improve the stability of color clusters. Discriminant analysis of color distributions was employed to distinguish nine types of brown rice kernels. Discrimination accuracies of the on-line discrimination algorithm were ranged from 72% to 85% for the sound, cracked, green-transparent and green-opaque, greater than 93% for colored, red, and unhulled, about 92% for white-opaque and 67% for chalky, respectively.

• The Korean Journal of Applied Statistics
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• 제25권5호
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• pp.837-846
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• 2012

Monte Carlo methods have been used in exact inference for contingency tables for a long time; however, they suffer from ergodicity and the ability to achieve a desired proportion of valid tables. In this paper, we apply the stochastic approximation Monte Carlo(SAMC; Liang et al., 2007) algorithm, as an adaptive Markov chain Monte Carlo, to the exact test of mutual independence in a multiway contingency table. The performance of SAMC has been investigated on real datasets compared to with existing Markov chain Monte Carlo methods. The numerical results are in favor of the new method in terms of the quality of estimates.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.I
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• pp.276-279
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• 2005

The proposed Novel OverDriving Technology with Optimum Look-up-Table（LUT）is suggested to be a better solution to reducing the occurrence of overshooting caused by the traditional overdriving method implemented to normally liquid crystal (VA mode). Chunghwa Picture Tubes, LTD. (CPT) has successfully implement this tech into 20 inch TFTLCD TV module at the present day. The proposed technology can speed up gray-to-gray response time of LCD less than one half of frame time. On the side, Optimum LUT construction apply the compression scheme to record total actual grayscale transfer characteristics instead of applying the normal spread method such as linear / non-linear interpolation. The memory space is been reduced and the distortion of the image quality is lesser.

• The Transactions of the Korean Institute of Electrical Engineers D
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• 제52권12호
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• pp.671-678
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• 2003

This paper proposes an expert system to generate automatically the test table of test system which can highly enhance the quality and productivity of product by inspecting quickly and accurately the defect device on the electronic circuit board tested. The expert system identifies accurately the tested components and the circuit patterns by tracing automatically the connectivity of circuit from electronic circuit database. And it generates automatically the test table to detect accurately the missing components, the misplaced components, and the wrong components for analog components such as resistance, coil, condenser, diode, and transistor, based on the experience knowledge of veteran expert. It is implemented in C computer language for the purpose of the implementation of the inference engine using the dynamic memory allocation technique, the interface with the electronic circuit database and the hardware direct control. And, the validity of the builded expert system is proved by simulating for a typical electronic board model.

• Journal of the Korean GEO-environmental Society
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• 제2권4호
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• pp.73-81
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• 2001

Soil cement has been the typical material for the pavement and soft ground improvement. It has not been used up to date because that quality control is not easy and durability is not long enough for practical application. Since environmental influence is important, the application of high strength soil cement pavement has been increased for pedestrian roads of the garden, golf courses and sidewalks recently. In this study, the reference table was suggested for mixing design with appling statistical experimental technique to reference table. The reference table showed the relationship among improved strength, Soilcrete stabilizer, fine sand ratio and superplasticizer agent. The objective soil used in this study was the soft marine clay that is widely found in Korea, the compressive strength range of improved soil was between $50{\sim}150kg/cm^2$.

• Journal of the Korean Institute of Landscape Architecture
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• 제30권6호
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• pp.38-46
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• 2003

Perceived crowding is known as a necessary method to evaluate social carrying capacity in recreational settings. But according to the results of previous research, perceived crowding, use density, and satisfaction have shown weak and indirect correlations. The theory of visitors’ adjustment is one of several possible explanations for this poor relation. But the validity of the visitors’ adjustment theory has not been not inspected clearly. Therefore, the purposes of this study are to understand visitors’ adjustment theory and to examine visitors’ adjustment to the overuse of recreational settings. Study hypotheses were formulated through literature review and related to visitors’ adjustment in recreation density. Pour hypotheses were established and inspected with the case study, i.e., Rationalization : Visitors’ satisfaction isn't related to use density in recreation setting, 2) Product-shift : Preference norm is related to current use density, 3) Self-selection : Visitors’ satisfaction for the use level is generally high, and 4) Displacement : Norm interference is related to willingness to revisit. The case study was conducted during May and June,2001. According to the results of this survey, visitors adjust to overuse of recreation setting through rationalization and product shift (hypotheses l/2 acceptance). Current use density isn't related to visitors’ satisfaction and willingness to revisit (see table 3). And visitors’ preference norm is modified by situation (see table 4). Visitors’ satisfaction and willingness to revisit don't show a high correlation but moderately high (see table 5, hypothesis 3 acceptance). Differences between visitors’ preference norm and current use density is norm interference. Norm interference isn't related to willingness to revisit (see table 7). Therefore, the norm interference concept is not a useful method to explain visitors’ adjustment to the degree of overuse in a recreational setting (hypothesis 4 rejection). As for future directions, the following are proposed: 1) correctly understanding and reestablishing the visitor norm and norm interference concept, 2) introducing a composite research method to monitor visitors’ behavior and survey visitors’ attitudes and coping responses. These efforts would be helpful in the Planning and management of recreational settings to improve the quality of visitors’ experiences.

• Journal of the Korea Concrete Institute
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• 제27권1호
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• pp.55-63
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• 2015

Prefabrication technologies are making bridge construction safer and less disruptive to the environment and traveling public, making bridge designs more constructible and, improving the quality and durability by shifting site work to a more controllable environment. Modular bridge substructures with concrete-filled steel tube (CFT) piers and composite pier caps were suggested to realize accelerated bridge construction. The precast segmental pier cap consists of a composite pier table and precast prestressed segments on the table. The pier table has embedded steel section to mitigate stress concentration at the connection by small tubes. Each bridge pier has four or six CFT columns which connect to the pier cap. Shear strength of the pier cap was obtained by extending vertical reinforcing bars from the table to the precast segment. Transverse prestressing was introduced to control tensile stresses by service loadings. Structural performance of the proposed modular system was evaluated by static tests. Design requirements of the composite pier cap were satisfied by continuous reinforcing bars and prestressing tendons. Standardized modular substructures can be effectively utilized for the fast replacement or construction of bridges.

• The KIPS Transactions:PartD
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• 제9D권4호
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• pp.651-658
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• 2002

This paper suggests the scenario composition supporting method, which can be used to perform integration test based on specification, and implemented a scenario composition supporting tool. To compose scenario for object-oriented integration testing, requirement specification, Process definition table and program to table relation diagram are used. In addition, requirement trace table is created. It can check user's requirements, quickly and exactly, dividing former three fables into the stages of requirement analysis, design, and test. The output of scenario composition supporting tool plays a guide part in composing scenario. This tool can reduce scenario composition effort of quality for the checking team and prevent an omission of requirement and input of errors during the test.