• Journal of Power Electronics
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• v.15 no.5
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• pp.1274-1285
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• 2015

This paper deals with model reference adaptive system (MRAS) speed estimators based on a secondary flux for linear induction motors (LIMs). The operation of these estimators significantly depends on an adaptation mechanism. Fixed-gain PI controller is the most common adaptation mechanism that may fail to estimate the speed correctly in different conditions, such as variation in machine parameters and noisy environment. Two adaptation mechanisms are proposed to improve LIM drive system performance, particularly at very low speed. The first adaptation mechanism is based on fuzzy theory, and the second is obtained from an LIM mechanical model. Compared with a conventional PI controller, the proposed adaptation mechanisms have low sensitivity to both variations of machine parameters and noise. The optimum parameters of adaptation mechanisms are tuned using an offline method through chaotic optimization algorithm (COA) because no design criterion is given to provide these values. The efficiency of MRAS speed estimator is validated by both numerical simulation and real-time hardware-in-the-loop (HIL) implementations. Results indicate that the proposed adaptation mechanisms improve performance of MRAS speed estimator.

• Journal of the Korean Vacuum Society
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• v.8 no.3B
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• pp.346-352
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• 1999

Diamond-like carbon (DLC) lims were deposited by using end hall type ion gun. Benzene gas was used for the generation of carbon ions. In order to systematically control the ion energy, we applied to the substrate DC, pulsed DC or 250 kHz medium frequency bias voltage, DLC films of superior mechanical properties of hardness 39$\pm$4 GPa and elastic mudulus 290$\pm$50GPa (2 to 6 times better than those of the films deposited by plasma assisted CVD method) could be obtained. Deposition rate was much higher than when using Kaufman type ion source, which results from higher ion beam current of end hall type ion gun. The mechanical properties and atomic bond structure were independent of the bias voltage type ion gun. The mechanical properties and atomic bond structure were independent of the bias voltage type but intimately related with the magnitude of the bias voltage. With increasing the negative bias voltage, the structure of the films changed to graphitic one resulting in decreased content of three dimensional inter-links. Degradation of the mechanical properties with increasing bias voltage could be thus understood in terms of the content odf three dimensional inter-links.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.62 no.5
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• pp.723-729
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• 2013

This paper presents an parallel type Linear Induction Motor with ununiform airgap for a shallow-depth underground train with 100‰ grade and 15 m curvature. This parallel type LIM has enough gradability but has inherently ununiform airgap between center and end parts. Consequently, performance when the train passes curved section should be considered with transient analysis. Moreover, general parallel operation, 1C2M which is usually used for train operation, deteriorates LIM performance because of different line velocity between inner and outer LIMs. Transient analysis has many problems such as huge model, lots of meshes, very long calculation time, truncation error and so on. This paper has presented a novel technique using equivalent linear rotating model in order to solve these problems and has analyzed parallel type LIM by using the proposed technique. Finally, LIM performance according to independent operating control has been investigated.

• Journal of Korean Physical Therapy Science
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• v.3 no.1
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• pp.871-879
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• 1996

The authors studied 74 patients with cal therapy Kosin University Medical March 1994 through February 1995. The results were, as follows: 1. Average age of the subject patients was 59.3 years old, their age ranged from 20 to 84 years old, and the incidence between male and female was 1:1.24 2. In respect to the economy level the middle class revealed the highest incidence, 40(54%) in 74cases. 3. The cause of injury revealed the highest incidence in hypertension 52 patients(72 %), more than all revealed the highest incidence 23 patients(44 %) in 60th years old. 4. The form of injury revealed the highest incidence in infarction 36 patients(49 %), more then all revealed the highest incidence 13 patients (36 %) in 60th years old. 5. As for the region cerebral artery of infarction patients, middle cerebral artery was the highest region of injury 72 %. 6. As for the physical paralysis side, the left side showed higher incidence 40 patients(54 %) compared to the right side 31 patients (42 %). 7. The period of therapy was 56 days, in average extending from 7 days to II months, nore then all there were the most numerous patients within 3 weeks 28 patients(38 %). 8. The upper side of the upper lims had improved 67 patients(91 %), the lower side 48(65 %). In the cases of the lower limb, the upper side had improved 70(95 %), the lower side 58(78 %). In short, patients had improved more the lower limb than the upper limb, the upper side(elbow and shoulder part) then the lower side(wrist and finger) of the upper limb. In the cases of the lower limb, patients had improved more the upper side (knee and hip part) then the lower side(foot and ankle) 9. In the cases of patients can be walking among subject patients 55(74 %) and patients cannot be walking 19 (26 %), In the cases of patients utilized assistant apparatus 34 (62 %) among self-walking, completely patients can be self-walking 21(28 %).

• Economic and Environmental Geology
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• v.45 no.5
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• pp.477-486
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• 2012

High-resolution bathymetry and physico-chemical properties of manganese nodules were explored to identify the relationship between morphological features and nodule occurrences in the KR1, one of the Korean contract nodule fields located in the NE Pacific. The high-resolution seabed mapping showed that the southwestern sector of the KR1 (KR1-1) was relatively deeper than the northeastern sector (KR1-2) which is occupied by small-scale seamounts. In terms of nodule occurrence, manganese nodules in the KR1-1 were comparatively larger (2-4 cm) with rough surface (t-type) and discoidal shapes (D-type), while those in the KR1-2 were generally small (<2 cm) with smooth surface (s-type) and irregular shapes (I-type). In addition, the nodules in the KR1-1 had higher contents of Cu, Mn and Ni. Such connections of water depths to nodule appearances and metal contents are commonly observed in the Pacific nodule fields. On the other hand, the nodules in the KR1-2 tend to be controled by morphological features. The seamounts in the KR1-2 might continuously provide rock fragments as new nuclei of manganese nodules. As a result, the nodules could not grow over than 2 cm and showed the shapes of a newbie (i.e., smooth surface and irregular shapes). As a result, our observations indicate that occurrence features of manganese nodules could be subjected to water depths and seabed morphology simultaneously.

• YAKHAK HOEJI
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• v.54 no.5
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• pp.341-347
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• 2010

The majority of forensic autopsies in Korea are performed by the National Institute of Scientific Investigation (NISI), and the NISI has carried out about 4,000 cases annually. Total 4,578 autopsies were performed by NISI in 2009, among them 2,918 cases (64%) were carried out at main office of NISI in Seoul, which is in charge of Seoul, Incheon and Gyeonggi province. In this study we investigated pattern of drugs & poisons in autopsy cases for recent three years in Korea. Postmortem specimens (bloods, gastric contents, etc) from autopsy cases by main office of NISI during 2007~2009 were screened for drugs & poisons. Using laboratory information management system of NISI (iLIMS), the kinds of drugs & poisons and the frequency were investigated. As the results, 1,705 cases were negative to drugs & poisons, it occupied 58% of total 2,918 autopsy cases in 2009. During three years (2007~2009), the kinds of drugs & poisons detected in specimens were 206, 185 and 203, respectively, and top three drugs were atropine (anticholinergic), chlorpheniramine (antihistamine) and lidocaine (local anaesthetic/anti-arrythmic). These drugs were supposed to be used not so much for suicidal or homicidal purpose as for therapeutic purpose in hospital. Meanwhile cyanide showed the highest frequency of poisons during 2007~2009, and the frequency was 32 cases in 2009. In case of pesticides, poisoning by paraquat (herbicide, 17 cases) showed the highest frequency, and methomyl (insecticide, 9 cases) and glyphosate (herbicide, 7 cases) were followed. Finally we selected 62 drugs as target drugs for systematic toxicological analysis (STA) for Korea. Poisons such as pesticides, natural toxins, volatile compounds should be included for STA in further study.

• Journal of Korean Society of Disaster and Security
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• v.9 no.2
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• pp.53-62
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• 2016

This paper is shown the new method using LED Light, which the light environment is upgraded the natural LED light in the area of Disaster Prevention and Safety Management (PDSD), which the events of deaths is reduced on the Suicide, the Infectious diseases, the safety accidents, the Traffic Accident, the crime, the fire, the Nature Disaster, and which the health and the environment and the safety is implemented using the value of the color LED Light. Research findings include,during 3 weeks in the November 2016, in the ten residents (average living 28.7 years, age 67.5 years) with depressive symptoms in the northern part of Seoul, according to the request of the user, the PDSD natural light LED lighting was installed in the home bedroom or the living room, expectations for the ability to restore physical and mental stability were high (88%), in the same way, after 1 week and 3 weeks, the physical and mental changes were compared and the results,84% in the first week and 90% in the third week and thereafter, the effect of relieving depression was high. We conclude that patients with depression have a good sleep, an uneasy feeling, a sense of security, a good night's sleep, and a good feeling. The PDSD LED Light is expected to contribute in the various areas, which reduced the suicides, which give increased immunity from infectious diseases, which give a crash to reduce accidents caused by negligence, which improve the safe operation of heavy vehicles in which a traffics accident incidence installed on the highest point, which improve the safety function on the 'safety way home' for the safety of the community, which due to fire gives alleviate the emotional anxiety of firefighters, which improve the environment for long-term control room working during decision making caused by natural disasters.