• Journal of the Institute of Electronics Engineers of Korea TE
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• v.42 no.1
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• pp.29-34
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• 2005

The wound induction motor can provide high starting torque and reduced starting current simultaneously by inserting large resistor externally when starting. And this technique is one of the well known methods among the induction motor starting methods and generally used for heavy load starting such as crane and cement factories. The conventional PI controller has been widely used in industrial application due to the simple control algorithm and is generally used for control of current torque, position, and speed for the wound induction motor drive system. However, the conventional control system for wound induction motor may result in poor performance because sensors have to be used but are often limited by the environmental condition. Recently, to overcome these problems, many sensorless vector control methods for the wound induction motor have been studied. This paper presents a MRAS method for sensorless vector control of the wound induction motor drive. In the conventional MRAS method, in low frequency, the stator resistance variation may result in poor performance. Therefore, this paper presents a MRAS method with stator and rotor resistance tuning for sensorless vector control of the wound induction motor to overcome several shortages of the conventional MRAS caused by parameter variation and to enhance the robustness of the sensorless vector control. The validity and effectiveness of the proposed method is verified through digital simulation.

• Journal of the Institute of Electronics and Information Engineers
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• v.52 no.12
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• pp.99-108
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• 2015

The embedded microcontroller which is operated by the logic gates synchronized on the clock pulse, is gradually used as main controller of mission-critical systems. Severe electrical situations such as high voltage/frequency surge may cause malfunctioning of the clock source. The tolerant system operation is required against the various external electric noise and means the robust design technique is becoming more important issue in system clock failure problems. In this paper, we propose on-chip backup clock change architecture for the automatic clock failure detection. For the this, we adopt the edge detector, noise canceller logic and glitch-free clock changer circuit. The implemented edge detector unit detects the abnormal low-frequency of the clock source and the delay chain circuit of the clock pulse by the noise canceller can cancel out the glitch clock. The externally invalid clock source by detecting the emergency status will be switched to back-up clock source by glitch-free clock changer circuit. The proposed circuits are evaluated by Verilog simulation and the fabricated IC is validated by using test equipment electrical field radiation noise

• Journal of Mushroom
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• v.15 no.1
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• pp.38-44
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• 2017

Sparassis latifolia (formerly S. crispa) is used in food and nutraceuticals or dietary supplements, as rich in flavor compounds and ${\beta}-glucan$. Some previous studies have reported the effects of mushroom on brain function, including its neuroprotective effect. Thus, for this mushroom to be used as an effective nutraceutical for brain function, it would be desirable for it to contain other compounds such as ${\gamma}-aminobutyric$ acid (GABA) in addition to ${\beta}-glucan$. In this study, the enhancement of growth and GABA production in the mycelium of medicinal and edible mushroom S. latifolia was investigated. Amino acids were added externally as the main source of nutrition, and the effects of amino acids were investigated using liquid medium, specifically amino acid-free potato dextrose broth (PDB). The amino acids added were L-glutamic acid (named PDBG medium) and L-ornithine (named PDBO medium). The growth of mycelia was determined to be $0.9{\pm}0.00g/L$, $2.2{\pm}0.16g/L$, and $1.93{\pm}0.34g/L$ PDBG respectively. The GABA content was $21.3{\pm}0.9mg/100g$ in PDB medium, and it in PDBG 1.4% medium, at $115.4{\pm}30.2mg/100g$. However, the PDBO medium was not effective in increasing the GABA content of mycelia. Amino acids had little effect on the ${\beta}-glucan$ content of mycelia. The ${\beta}-glucan$ content was $39.7{\pm}1.4mg/100mg$, $34.4{\pm}0.2mg/100mg$, and $35.2{\pm}9.2mg/100mg$ in PDB, PDBG 1.8% and PDBO 1.4% media, respectively. Addition of glutamic acid and ornithine positively affected the growth of S. latifolia mycelia, and glutamic acid positively affected GABA production; no degradation of GABA was observed with addition of glutamic acid.

• International Commerce and Information Review
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• v.7 no.4
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• pp.387-407
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• 2005

This paper is to study globalization motives and strategies of Japanese and Korean industries by analyzing the causes and patterns of foreign direct investment (FDI) of the firms of the two countries during the 1980s and 1990s. First we develop a FDI function from the profit maximizing model of firms. Then we use regression analysis to determine internally driving-out factors and externally-inducing factors. Japanese FDI strategy has gone through three different stages; from natural resource-seeking investment in the 1950s and 1960s to market-expansion investment in the 1970s and 1980s and to a combination of cost-reducing (low-cost labor-seeking) investment and market-penetrating investment in the 1990s. On the other hand, Korean FDI behavior has gone through four different stages; from the learning stage with small investments in the 1970s, to natural resource-seeking investment in the early and mid 1980s, to the growth stage in the late 1980s and the early 1990s, to the maturity stage of the mid and late 1990s. The last two stages were characterized by a combination of cost-reducing investment and market-seeking investment. As a late comer, Korea began its FDI two decades later than Japan, but caught up the patterns of Japanese FDI by the mid 1990s and is in a competing position with Japan. Our findings show that both Japanese FDI and Korean FDI in Asia and other developing countries tendto be in labor-intensive sectors where their firms are losing their comparative advantages at home. The main motive for FDI into these regions is low-cost resource seeking. On the other hand, both Japanese FDI and Korean FDI in the U.S. and Europe tend to be knowledge-intensive sectors where Japanese and Korean firms attempt to internalize transaction and information costs by globalizing its production. The main motive for FDI into these regions is market-seeking. Firms in both countries have increased their investments in Mexico and Western and Eastern Europe in order to penetrate large economic blocs such as the EU and NAFTA area. Korean firms are more aggressive in expanding into new and untested markets than are their counterpart in Japan. Evidence of this can be seen in the scarcity of Japanese FDI and abundance of Korean FDI in Eastern Europe and China.

• Journal of Nutrition and Health
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• v.37 no.8
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• pp.688-700
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• 2004

This study was conducted to analyze how appropriate the on-line nutrition information was externally as a web information. Four-hundred-ninety-seven web sites from 5 internet search engines (Yahoo, Empas, Nate, Hanmir, Naver) were selected on the basis of April 25th, 2004. The skillful personnels monitored them about 8 evaluating categories: clarity, purpose, authority, durability, advertisement, privacy and/or security, responsibility, and contents. Forty percent of the selected web sites were operated by the companies which had commercial purpose like internet shopping malls and 5.6% by academies, societies, research institutions, schools/colleges and public institutions. Most of web sites (76.1 %) were managed for advertisements and sales of companies' commodities, and 32.6% had the food and nutrition information as first purpose. Ninety-three percent of web sites were targeted to healthy individuals through whole life cycle. Specifically, there were lots of web sites for the obesity which were offered by diet related companies. Of the 497 web sites, 193 mentioned the name providing the nutrition information, but only 1/3 had reliability on their specialty. As a source of nutrition information, 52.7% of web sites were using 'books of the major field' and 42.0% 'newspapers' and 23.7% 'broadcasting', respectively. Most web sites mentioned 'setting-up date' but not 'renewal date'. Thirty-six percent of web sites took '2 - 3 days' for the operators to answer the questions through the bulletin. Forty-seven percent of web sites answered' 1 - 10 questions' per 1 week, but 40.1 % of them didn't answer for a week at all. There were 118 web sites (23.7%) to record the connected frequencies and 36.0% of them put the advertisements. Around 96% of web sites mentioned feedback addresses. Among the menus of web sites, 68.0% were about self-advertisement and 64.0% about nutrition information. Each web site was scored to judge its external quality according to the operators by selecting 13 items. Web sites managed by public institution had highest scores (9.5), and lowest in private vendors', food companies' and individual web pages. Among search engines, Naver got the highest score of 7.0 and Nate the lowest one of 6.1. As it was only the pilot study, there were several limits in evaluating tools, time and monitored quantity. To make monitoring of on-line nutrition informatiions actively, standardized monitoring forms might be developed under the integrated studies.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.10 no.6
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• pp.47-57
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• 2015

This study examines whether successful stand-alone firms have more difficulties than the successful firms affiliated to business groups in external financing. The easiness of external financing is measured by investment-cashflow multiple. Controlling the effects on the multiple of the past business performances and the expectation of future business performances, we investigate how the ownership type affects the multiple. The empirical results show that, when cashflows are positive, the stand-alone firms exhibit higher investment-cashflow mupltiples. When cashflows are negative, however, the opposite is true, even though the statistical significance of the result is rather low. These results do not support the general idea that stand-alone firms must have more disadvantage than subsidiary firms in raising funds from outside. If member firms of business groups have no big trouble financing externally, then the above results imply that stand-alone firms do not either identify external financing as a major difficulty in running business. Thus, if the government seeks to formulate the selective policies supporting only the promising start-ups, instead of the general policies benefiting random start-ups, then the start-up financing policy should have a lower priority.

• The Journal of Korean Physical Therapy
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• v.14 no.3
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• pp.355-372
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• 2002

The purpose of this study was to evaluate the effect of multiaxial lower extremity orthosis on correction of genu valgum. 20 volunteers among people visited department of Rehabilitation Medicine, chungnam national university hospital, who had been diagnosed as genu valgum without other musculoskeletal problems were included. 10 individuals(mean age: 9.gyrs) who had been taken multiaxial lower extremity orthosis at least 12month were included in experimental group and the other 10 individuals(mean age: 11.7yrs) refused taking this orthosis in the control group. We measured the Q-angle & femorotibial angle using plain roentgenogram images at visiting day and repeat same test after 1year follow up. Multiaxial lower extremity orthosis consist of proximal horizontal bar with both thigh cuff, central vertical bar and distal horizontal bar with both shoes. we narrowed inter-shoes distance from start to 6th month and inter-thigh cuff distance together with above correction for next 6month in the frontal plane and from 10th month, dorsiflexed both shoes in sagittal plane. Also, we rotate the both shoes externally and retract the proximal vertical bar every month. This orthosis have to be taken at least 4 hours during sleep. The result were as follows 1. There were no statistical significant difference in each parameter between the right and left Q-angle before multiaxial lower extremity orthosis. 2. The left Q angle reduced $-11^{\circ}$ between 1st day and after 1year follow up showed statistical significant difference between multiaxial lower extremity orthosis taking group and non-taking(p<0.001). 3. The right Q angle reduced $-13^{\circ}$ between 1st day and after 1year follow up showed statistical significant difference between multiaxial lower extremity orthosis taking group and non-taking(p<0.001). 4. There were no statistical significant difference in each parameter between the right and left femorotibial angle before multiaxial lower extremity orthosis. 5. The left femorotibial angle reduced $-10.1^{\circ}$ between 1st day and after lyear follow up showed statistical significant difference between multiaxial lower extremity orthosis taking group and non-taking(p<0.001). 6. The right femorotibial angle reduced $-11.2^{\circ}$ between 1st day and after 1year follow up showed statistical significant difference between multiaxial lower extremity orthosis taking group and non-taking(p<0.001).

• Journal of Chest Surgery
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• v.36 no.2
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• pp.109-112
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• 2003

Stromal tumors of the gastrointestinal tract, especially of the esophagus, are rare. We had a case of malignant gastrointestinal stromal tumor(GIST) of the esophagus. A 46 years old woman was admitted for abnormal mass shadow in the chest radiograph. The mass was originated from the lower thoracic esophagus, and compressed the right lower pulmonary vein and the inferior vena cava. We removed the tumor externally without injuring of the esophageal mucosa via right posterolateral thoracotomy. The tumor was positive for CD 34 and CD 117, and diagnosed malignant CIST of the esophagus.

• Journal of the Korean Regional Science Association
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• v.6 no.1
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• pp.11-38
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• 1990

The purpose of this thesis is, first to present the spatial division of labor in Korea and its mechanism, and second, to elucidate the organic integral relation between local labor market and local community by studing the mechanism that the spatial division of labor is projected into the individual lacal labor marker, and reproduction of labor force process in this local labor market. According to this purpose, the theoretical frame of this analysis is done, the positive analysis is made and Kumi is choosed as its analysis case area. The main data is from 'Survey Report on Manufacturing Idustry Wage Conditions' published by Minimum Wage Council, Ministry of Labour and from the questionnaires and interview on textile industry and electric electronics industry firms in Kumi Export Industrial Estate. The following are the results of this study. 1. The mechanism of spatial division of labor in Korea, seen through the employment structure index, is accelerating the regional discrimination by fixing the regional hierarchisation between Seoul (or Seoul Metropolitan Area as expanded Seoul) and other areas. But it is also developing highly the regional employment structure at the level of technical division of labor, since the spatial division of labor in Korea is leaded by large firms and influenced by the policy for regional development. 2. Local labor market is formed in Kumi area and its delimitation is Kumi city. The employment structure of Kumi local labor market is occupying lower hierarchy division at management hierachical level and occupying upper hierarchy division at the level of technical division of labor, and brand plants of large firs are determinating and dominating this emplogment structure. These bdranch plants of large firs are forming more favorable and stabel labor marker than locally controlled ploants in Kumi local labor market. But the reproduction of labor force process in Kumi local labor market is not fully carried out and leaked into central city, therefore Kumi is now becoming an unstable local community, suffering from large movement of population. This is because Kumi local labor market is found not for itself, but by the state policy and externally controlled plants of large firms, and therefore no potentiality to control and to absorb the exterior influences is built in Kumi local labor market. 3. The case firms A, B have spatial division of labor between decision-making function and production function, and between upper management hierachical labor force and lower management hierachical labor force in internal labor market.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.38 no.1
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• pp.1-10
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• 2018

It is difficult to predict the early-age cracks of strain restrained concrete members due to environmentally sensitive parameters. A new method is proposed to predict the cracks by test of autogenous deformation and self-induced restrained stress of specimens which simulates early-age crack state by hydration heat of the'Wall-On-Foundation'members. For this purpose, thermal analysis of entire structure considering the environmental condition is performed at first, and the specimens are set up where hydration heat was electronically controlled according to the analysis results. By measuring free deformation and force to compensate the autogenous strain including relaxation, feasibility of cracks can be estimated. The proposed method can predict the occurrence of cracks better than the material test of the early age concrete which has large variance. The method of this study is particularly useful when it is used as a preliminary experiments to predict the crack more precisely before full-scale concrete placement in construction of large structures.