• Bulletin of the Society of Naval Architects of Korea
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• v.23 no.4
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• pp.25-34
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• 1986

A two-dimensional linear method has been developed for the motion and the second-order steady force arising from the hydrodynamic coupling between waves and currents in the presence of a body of arbitrary shape. Interaction between the incident wave and current in the absence of the body lies in the realm beyond our interest. A Fredholm integral equation of the second kind is employed in association with the Haskind's potential for a steadily moving source of pulsating strength located in or below the free surface. The numerical calculations at the preliminary stage showed a significant fluctuation of the hydrodynamic forces on the surface-piercing body. The problem is approximately solved by using the asymptotic Green function for $U^2{\rightarrow}0$. The original Green function, however, is applied for the fully submerged body. Numerical calculations are made for a submerged and for a half-immersed circular cylinder and extensively for the mid-ship section of a Lewis-form. Some of the results are compared with other analytical results without any available experimental data. The current has strong influence on roll motion near resonance. When the current opposes the waves, the roll response are generally negligible in the low frequency region. The current has strong influence on roll motion near resonance. When the current opposes the wave, the roll response decreases. When the current and wave come from the same direction, the roll response increases significantly, as the current speed increases. The mean drift forces and moment on the submerged body are more affected by current than those on the semi-immersed circular cylinder or on the ship-like section in the encounter frequency domain.

• Journal of the Korea Society of Computer and Information
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• v.16 no.3
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• pp.261-268
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• 2011

Juvenile crime has recently severe problems in quality as well as great increase in quantity. Especially compared to adult crime, juvenile crime has higher recidivism rate, which leads to strong doubt about the limitations of existing treatment. This is because the correctional institutions have a bad influence on the juvenile criminal, that is not the original purpose like correction and edification, but relearning of crime. To prevent the recidivism of juvenile crime needs an active level in terms of the return as sound citizens through correction beyond a simple level of maintaining order. Correction welfare is one of the most important measures to prevent the recidivism of juvenile crime. This study examines the notion, types and trend of juvenile crime, considers the concept and functions of correction welfare, and shows the prevention of recidivism of juvenile crime in perspective of correction welfare.

• YAKHAK HOEJI
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• v.4 no.1
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• pp.50-52
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• 1959

In order to know contents of vitamin B$_{12}$ in the fermented foods in Korea, the contents of this vitamin are studied on the following foods; kimchies (pickled vegetables) .................. 39 chukkals (fermented and salted sea foods) ...... 8 fermented soy-bean products .................... 5 the kimchies and fermented soybean products studied in this paper, are from individual homes and chukkals are from markets. The content of vitamin B$_{12}$ is estimated by the microbiological assay method using lactobacillus leichmannii ATCC 7830. Details for assay are indicated in the original part of this paper. The pseudo-vitamin B$_{12}$ substances as thymidine which is active to the growth of lactobacillus leichmannii, are eliminated by the alkali treatment method of sample solution. According to the results as indicated in the table, the following conclusions are summerized; 1. Vitamin B$_{12}$ contents of kimchies for winter season are 1.03 to 1.52 mcg% in average. The hobakk-kimchi which contain the highest content of vitamin B$_{12}$ is not popular one among Korean. 2. Chukkals contain much higher content of vitamin B$_{12}$ varying from 0.91 to 11.10mcg%. 3. The soybean fermented foods, as kanjang, denjang, kochojang, contain lower content of vitamine B$_{12}$ varying from 0.08 to 0.52 mcg% containing higher content of pseudo-vitamin. 4. Based on daily consumption of kimchi in winter season by Chai, the consumption of this vitamin through kimchi is about 3 mcgs daily per capita. This will be a quite source of this vitamin for Korean as vitamin C. as vitamin C.

• YAKHAK HOEJI
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• v.4 no.1
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• pp.53-55
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• 1959

In order to confirm on production of vitamin $B_{12}$ during the kimchi fermentation period, the variation of its content is studied in this paper As a sample of kimchi for this fermentation study due to the seasonal condition, nabakkimchi which is aseasonal one in early spring, is prepared by author. The content of vitamin $B_{12}$ is estimated by the microbiological assay method using lactobacillus leichmannii A Tee 7830. Details for assay are indicated in the original part. And the pseudo-vitamin $B_{12}$ substances as thymidine which is active to the growth of lactobacillus leichmannii, are eliminated by the alkali treatment method of sample solution, According to the results shown in table 2 and 3 and figures 1 to 4, the following conclusions are summerized; 1. Vitamin $B_{12}$ produced during the fermentation period of kimchi. And the content of this vitamin during its optimum fermentation period, is much higher content compared with the theoretically calculated amount from its materials, This has been confirmed at the repeated experiment. The trend of variation during its period is indicated at the figures. 2. The sterilized kimchi inhibited the fermentation by sterilization at the preparation, did not increased its content showing only its theoretically calculated amount.

• Korean Journal of Food Science and Technology
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• v.11 no.1
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• pp.18-25
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• 1979

In order to investigate the effect of polishing washing and cooking processes on the residue level of BHC in rice grain, brown rice samples having a 0.3 ppm total BHC content were subjected to various treatments and residue analysis. The results are summarized as follows: 1) The conventional polishing process of brown rice decreased the residue level down to 8 and 20% for 100 and 70% polished rice, respectively. 2) The washing procedure decreased the level to 34 and 31% for 100 and 70% polished rice, respectively. 3) The cooking processes with a conventional kettle and an automatic electric cooker decreased the residue level to 86 and 77% in 100% polished rice, and 69 and 41% in 70% polished rice, respectively. 4) By summation of the above results in sequence. it was concluded that the residue levels of BHC in cooked rice were 2.3 and 4.3% of original residue in the brown rice for 100 and 70% polished rice, respectively.

• Korean Journal of Materials Research
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• v.25 no.10
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• pp.552-558
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• 2015

The mechanical properties and microstructures of Aluminum 6056 alloys were investigated for their use in the fabrication of a piton block. The EN-AW6056 alloys exhibited a tensile strength of 375 MPa for a solution treatment temperature of $550^{\circ}C$ for 2 h followed by an aging treatment at $190^{\circ}C$ for 4 h. The microstructures of the heat treated specimen showed that the $Mg_2Si$ phase with a size of 3~5 um was dispersed throughout the aluminum matrix when the heat treatment was done. Moreover, in order to identify the forgeability of the specimen, upsetting tests were done. For up to 80 % of the upsetting ratio, the specimen maintained its original shape, and at above 80 % of the upsetting ratio, the specimen underwent crack development. The specimen was successfully forged without any defects with the examined material conditions. The material conditions together with the forging conditions are discussed in terms of the microstructures and mechanical properties.

• Journal of the Korea Institute of Building Construction
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• v.14 no.5
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• pp.467-476
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• 2014

According to the expanding of construction machinery works, the number of civil complaints demanding compensations are increasing continuously from surrounding residents due to the noise from construction fields. However, the noise is usually managed restrictedly during the construction phase rather than prevented in advance. So, the efforts to solve the noise problem are occurring only after complaints have been made. Also, excessive cost and time consuming in order to solve the complaints negatively affects to construction companies. Therefore, the purpose of this study is to develop an optimized scheduling process model for controlling the noise in construction field by considering the planned time, cost, and the number of equipment before construction. In addition, this process model is expected to provide a useful information about the cost comparison between the original planned cost plus compensation and the optimized cost considering noise limitation so that the site managers can manage their projects effectively.

• Journal of the Korea Convergence Society
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• v.11 no.5
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• pp.299-307
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• 2020

The purpose of this study was to explore what chiefs of tong/ri' experiences in suicide prevention activities are and what their changes are. The study participants are three chiefs of tong/ri who have participated in suicide prevention activities for more than two years in the community. In order to gain a deeper understanding of their respective experiences, used a qualitative method of narrative study. Chiefs of tong/ri' experiences experience in participating in suicide prevention activities consisted of start, experience, change and growth. The meaning is as follows. They did a "light start" with the idea that they could do it easily in their original activities. "Escape from the burden" of learning and maintaining each of own ways in the difficult problem of suicide prevention, "Responsibility as a chief" was the driving force behind suicide prevention activities. They were able to find "change of their own" because of the activity naturally.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 1998.10a
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• pp.211-217
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• 1998

Many practical control problems for the complex, uncertain or large-scale plants, need to simultaneously achieve a number of objectives, which may conflict or compete with each other. If the conventional optimization methods are applied to solve these control problems, the solution process may be time-consuming and the resulting solution would ofter lose its original meaning of optimality. Nevertheless, the human operators usually performs satisfactory results based on their qualitative and heuristic knowledge. In this paper, we investigate the control strategies of the human operators, and propose a fuzzy model-based multi-objective satisfactory controller. We also apply it to the automatic train operation(ATO) system for the magnetically levitated vehicles(MAGLEV). One of the human operator's strategies is to predict the control result in order to find the meaningful solution. In this paper, Takagi-Sugeno fuzzy model is used to simulated the prediction procedure. Another str tegy is to evaluate the multiple objectives with respect to their own standards. To realize this strategy, we propose the concept of a satisfactory solution and a satisfactory control scheme. The MAGLEV train is a typical example of the uncertain, complex and large-scale plants. Moreover, the ATO system has to satisfy multiple objectives, such as seed pattern tracking, stop gap accuracy, safety and riding comfort. In this paper, the speed pattern tracking controller and the automatic stop controller of the ATO system is designed based on the proposed control scheme. The effectiveness of the ATO system based on the proposed scheme is shown by the experiments with a rotary test bed and a real MAGLEV train.

• Journal of the Korean Institute of Intelligent Systems
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• v.7 no.5
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• pp.34-45
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• 1997

In this paper, we present hardware implemcntation of self-organizing feature map (SOFM) neural networkwith constant adaptation gain and binary reinforcement function on FPGA. Whereas a tnme-varyingadaptation gain is used in the conventional SOFM, the proposed SOFM has a time-invariant adaptationgain and adds a binary reinforcement function in order to compensate for the lowered abilityof SOFM due to the constant adaptation gain. Since the proposed algorithm has no multiplication operation.it is much easier to implement than the original SOFM. Since a unit neuron is composed of 1adde $r_tracter and 2 adders, its structure is simple, and thus the number of neurons fabricated onFPGA is expected to he large. In addition, a few control signal: ;:rp sufficient for controlling !he neurons.Experimental results show that each componeni ot thi inipiemented neural network operates correctlyand the whole system also works well.stem also works well.