• Title/Summary/Keyword: internal reduction

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Design of Brushless Permanent Machine with Skewed Stator for Electrical Power Steering System (전동 조향 장치용 브러쉬리스 영구자석 전동기의 스테이터 스큐 설계)

  • Lee, Choong-Sung;Jung, Kyung-Tae;Hong, Jung-Pyo;Kim, Hae-Joong;Kim, Young-Kyun
    • Journal of the Korean Magnetics Society
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    • v.25 no.6
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    • pp.189-197
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    • 2015
  • As enforced the regulation of fuel efficiency, the electrification of automotive components in internal combustion vehicle has been applied instead of hydraulic pressure. A typical example of such parts is the EPS (electric power steering), and it is applied to most automotive at present. In electric power steering system, the core component is motor. The reduction of cogging torque and torque ripple is required to improve steering feeling and reduce NVH (Noise Vibration Harshness) in EPS. Generally the skewed design of stator or rotor is applied in order to reduce cogging torque and torque ripple. This paper propose the design and analysis methodology of Brusheless PMSM (Permanent Magnet Synchronous Motor) which is applied to skewed stator. The proposed methodology is as follows: First Intial Design PMSM with skewed stator for EPS, Second Optimal design using RSM (Response surface method), Third Performance Analysis such as Phase Back EMF, Inductance, Load torque using FEA (Finite Element Method). Finally, the reliability of proposed design methodology will be verified through the experiments of prototype sample.

Quality Characteristics of Bakery Products with Whole Green Wheat Powder (녹색 밀을 첨가한 베이커리 제품의 품질 특성)

  • Kim, Jin-Young;Lee, Ki-Teak;Lee, Jeung-Hee
    • Korean journal of food and cookery science
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    • v.29 no.2
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    • pp.137-146
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    • 2013
  • Premature-green wheat is typically obtained by early harvest when culms of wheat still appear green in color, and the wheat and its food products have been considered as wellbeing foods. The pasting properties of prematured whole green wheat powder (WGWP), were analyzed with a rapid viscosity analyzer (RVA), and compared with commercial flours. The RVA values of lower peak viscosity and time, holding strength, final viscosity, as well as breakdown and setback viscosity showed that the WGWP could retard a gelatination of starch and also delay retrogradation in bakery products. WGWP with different levels of 10, 20, 30 or 50% was added into flours for preparing bakery product (bread, muffin and cookie), and their quality properties were evaluated. The addition of WGWP lead to a reduction in loaf volume of bread and muffin, and bakery products containing different levels of WGWP showed the changed internal surface structure (e.g. pore size) observed with a scanning electron microscope when compared with the control (0% WGWP). The hardness, gumminess, chewiness of bread and muffins were increased, and cohesiveness was decreased as the WGWP content increased, but the hardness of cookies was decreased. The bakery products added WGWP showed darker and more greenish and yellowish color than control (p<0.05). The sensory evaluation showed that bakeries with WGWP were scored to have more greenish taste and green color (p<0.05), and muffins and cookies with WGWP were evaluated to have more nutty and less oily taste (p<0.05).

Experimental Study on Moisture Content According to Addition of Surfactants (계면활성제 첨가에 따른 함수율에 관한 실험적 연구)

  • Kim, Nam-Kyun;Rie, Dong-Ho
    • Fire Science and Engineering
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    • v.29 no.2
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    • pp.79-83
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    • 2015
  • The fire accident is a representative type of disaster that can largely impact on business. Therefore, precautionary measures and rapid initial response is very important when a disaster occurs. The storage of porous combustibles is inevitable in coal yard, plywood processing industry, and others that are currently operating. Initial fire fighting of fire and identifying the ignition point in such a porous combustible storage space are so difficult that if the initial response is failed, being led to deep-seated fire, surface fire is likely to result in secondary damage. In addition, deep-seated fire can cause personal injuries and property damage due to a large amount of toxic gases and reignition. Therefore damage reduction measures is required around the storage space to handle a porous flammable. Improving the penetration performance of the concentration of the surfactant is carried out as underlying study, which is about an deep-seated fire extinguishing efficiency augmentation when using wetting agents. The porous materials used in the experiments is radiata pine wood flour, which occupies more than 75% of the domestic wood market. Fire fighting water is selected as Butyl Di Glycol (BDG), which is being used for infiltration extinguishing agent, and the experiment was carried out by producing a standard solution. The experiment was carried out on the basis of the Deep-Seated Fire Test of NFPA 18. The amount of watering, porous material to the internal amount of penetration, and runoff measurement out of the porous material was conducted. According to experimental results, as the surface tension is reduced, the surfactant concentration macroscopic penetration rate decreases, but infiltration to a porous material is shown to have growth characteristics.

Capsaicin Intake Estimated by Urinary Metabolites as Biomarkers (뇨중 대사체 정량에 의한 capsaicinoid의 생화학적 섭취지표 개발 연구)

  • Choo, Yeon-Soo;Kwon, Hoon-Jeong
    • Korean Journal of Food Science and Technology
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    • v.33 no.6
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    • pp.784-788
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    • 2001
  • Reliable data on the exposure of capsaicin, which evokes hot sensation in hot red pepper, are important prerequisites for studying biological functions of capsaicin in human body since its roles are controversial according to animal and epidemiological studies. To get accurate data, the use of urinary biomarkers was considered as a measure of internal exposure of capsaicin. After 2-day-capsaicin depletion five to six women in their 20's were instructed to eat 60 or 80 g/day hot red pepper soybean paste as a capsaicin source with meal which did not contain capsaicinoid, and to collect their urine separately. HPLC conditions were set to detect capsaicinoid and urinary metabolites at the same time. Most of capsaicinoid were excreted in the form of 4-hydroxy-3-methoxybenzoic acid in three subjects at the highest dose. This result suggests the oxidation of the 4-hydroxy3-methoxybenzaldehyde, the hydrolysis product of capsaicin, is the major metabolic pathway in the human body, whereas the reduction of the aldehyde is the major route in rats. However, neither any metabolite nor the parent compound was ever shown in two of the subjects reflecting large individual differences of capsaicin absorption and/or biotransformation.

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Effect of Mercuric Chloride on the Contents of Mineral Nutrients in the Liver and Kidney of Rats (흰쥐의 간장(肝臟) 및 신장(腎臟) 무기질(無機質)에 미치는 수은(水銀)의 영향(影響))

  • Cho, Soo-Yeul;Park, Sun-Woo;Lee, Sang-Il
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.13 no.1
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    • pp.22-26
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    • 1984
  • The effect of changes in body weight, some blood components and some inorganic ions in liver and kidney, were studied on male rats receiving ad libitum on 5, 40, and 200 ppm of mercuric chloride solution during so days. The results obtained were summarized as follows ; 1. The total body weights were decreased in proportion to increment of mercury concentration. The internal organs weights i. e. , liver, kidney, spleen, and heart, were generally increased. Especially, the weight increment of kidney was the highest by intaking of mercuric chloride solution. 2. There were no significant changes in hematocrit values, activities of GOT and GPT in blood of rats receiving mercuric chloride. On the other hand, the plasma levels of cholesterol were significantly increased. The receiving of 200 ppm mercuric chloride solution to rats was resulted in the remarkable reduction of total protein levels and A/G ratio in plasma. 3. The markable rise occured in the accumulation of Hg, in both liver and kidney in proportion to supplying in rats while there was a tendency decreasing of Cu, Zn contents in liver, whereas there was a tendency increasing of Cu, Zn in kidney of rats.

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Test Time Reduction of BIST by Primary Input Grouping Method (입력신호 그룹화 방법에 의한 BIST의 테스트 시간 감소)

  • Chang, Yoon-Seok;Kim, Dong-Wook
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.37 no.8
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    • pp.86-96
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    • 2000
  • The representative area among the ones whose cost increases as the integration ratio increases is the test area. As the relative cost of hardware decreases, the BIST method has been focued on as the future-oriented test method. The biggest drawback of it is the increasing test time to obtain the acceptable fault coverage. This paper proposed a BIST implementation method to reduce the test times. This method uses an input grouping and test point insertion method, in which the definition of test point is different from the previous one. That is, the test points are defined on the basis of the internal nodes which are the reference points of the input grouping and are merging points of the grouped signals. The main algorithms in the proposed method were implemented with C-language, and various circuits were used to apply the proposed method for experiment. The results showed that the test time could be reduced to at most $1/2^{40}$ of the pseudo-random pattern case and the fault coverage were also increased compared with the conventional BIST method. The relative hardware overhead of the proposed method to the circuit under test decreases as th e size of the circuit to be tested increases, and the delay overhead by the BIST utility is negligible compared to that of the original circuit. That means, the proposed method can be applied efficiently to large VLSI circuits.

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A Case Study on the Reinforcement of Existing Damaged Geogrid Reinforced Soil Wall Using Numerical Analyses (수치해석을 이용한 기존 피해 보강토 옹벽의 보강에 관한 사례 연구)

  • Won, Myoung-Soo;Langcuyan, Christine P.;Choi, Jeong-Ho;Ha, Yang-Seong
    • Journal of the Korean Geosynthetics Society
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    • v.19 no.1
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    • pp.75-82
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    • 2020
  • There have been often cases of collapse for geogrid reinforced soil (GRS) retaining wall. Hence, social interest in the reinforcement and restoration of the collapsed GRS wall is increasing day by day. However, there are only few researches. For this reason, a series of numerical analyses using the Plaxis 2D program was conducted in this study to analyze the suitable reinforcement methods that can be applied on the existing damaged GRS wall caused by overturning of the modular blocks facing and the surface settlement at the backfill as the results from the design failure. The restoration plan used in this study is composed of two cases: (Case 1) soil nailing reinforcement and reinforced concrete (RC) wall facing construction on the existing damaged GRS wall; and (Case 2) removal of the entire damaged GRS wall and then reconstruction. The results on the internal stability of the GRS wall show that Case 1 obtained a greater safety factor than Case 2 for tensile force while Case 2 had a greater safety factor than Case 1 for pullout failures. Case 1 was found to be more stable than Case 2 in terms of the global slope safety by shear strength reduction method and the external deformation behavior by numerical analysis. In this study, the existing damaged GRS wall which was reinforced using Case 1 method shows more stable external behavior.

Operative Treatment of Tibial Plateau Fractures (경골과 골절의 수술적 치료 결과)

  • Shin, Duck-Seop;Seong, Byeong-Yeon;Kim, Dong-Won
    • Journal of Yeungnam Medical Science
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    • v.18 no.2
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    • pp.187-198
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    • 2001
  • Background: The purpose of this study was to evaluate the relationship between variable factors and clinical results following the operative treatment of the tibial plateau fractures. Materials and Methods: The clinical and radiological analysis was performed on 29 cases of the tibial plateau fractures who had been treated with operative treatment and followed up for more than 1 year from January 1991 to December 1997. The analysis of clinical results was performed dividing into age, cause of injury, fracture type of Schatzker classification, associated soft tissue injury and method of operative treatment. Results: According to Schatzker classification, 2 cases(6.9%) were type I, 11 cases(37.9%) were type II, 1 case(3.5%) was type III, 5 cases(17.2%) were type IV, 4 cases(13.8%) were type V, and 6 cases(20.7%) were type VI. In all cases, bony unions were obtained. According to Blokker evaluation, 23 cases(79.3%) of 29 cases were acceptable. Conclusion: We could expect good clinical results if early knee joint mobilization following minimal invasive open reduction and internal fixation could be obtained. Bad clinical results were related with young age group under 30, more than Schatzker classification type IV of high energy trauma and associated injury of anterior cruciated ligment or meniscus.

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THE STUDY ON THE DEVELOPMENT OF RELATIVE VALUE IN MEDICAL TREATMENT OF THE ORAL AND MAXILLOFACIAL SURGERY (구강악안면외과 의료행위 상대가치 개발에 대한 조사연구)

  • Song, Gin-Ah;Baek, Kyung-Won;Hwang, Jong-Min;Yu, Soon-Yong;Choi, Jin-Young
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.32 no.4
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    • pp.334-347
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    • 2006
  • The aim of this study is to evaluate the reasonableness of the medical fee on oral and maxillofacial surgery field according to surgeon's opinions and actual conditions. The medical fee has significant influence on hospital income, the supply and distribution of medical manpower, quality and facilities of medical services. Questionnaire survey was sent to 86 oral and maxillofacial surgeons who worked more than 3 years in general hospital. Among them, 25 doctors replied the 109 answers survey and the average of treatment time and physician work relative value on each category was calculated. And the health insurance cost (that has been applied since 2003) was compared with the questionnaire results. And finally we investigated items that health insurance system did not include in oral and maxillofacial field but actually performed in oral and maxillofacial surgery clinic. The result was that the medical fee did not properly reflect physician work relative value of actual treatments. In case of complicated extraction, work relative value needed 3.5 times enhancement of present value. For simple impacted tooth extraction 1.8 times, for impacted tooth extraction including odontomy 1.7 times, and for fully impacted tooth more than 2/3 of it located into the alveolar bone, 1.8 times enhancement needed. In respect of the present physician work relative value, hemimandibulectomy with neck lymph node dissection for the malignancy is appropriated as 3.3 times of open reduction and internal fixation for the mandibular fracture, but the questionnaire result showed 25 times discrepancy. In conclusion, this research shows the need for intervention that health insurance included items and legal relative medical value must act in union with treatment in clinic to reduce the imbalance between them.

Effect of Modified Atmosphere Packaging on Preservation of Pumpkin Rice Cake (호박 설기떡의 저장성에 미치는 변형기체포장의 영향)

  • Moon, Ki-Bok;Kim, Hwan-Ki;An, Duck-Soon;Lee, Dong-Sun
    • Food Science and Preservation
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    • v.17 no.6
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    • pp.908-913
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    • 2010
  • Modified atmosphere packaging (MAP) was evaluated for the storage of pumpkin rice cake as a means of preserving quality and extending shelf-life. Retail-sized amounts of rice cake were packaged in trays under different modified atmosphere conditions (air, vacuum, 60% $CO_2$/40% $N_2$ and 100% $CO_2$) using gas-barrier plastic film; control was in air-permeable stretch wrap. The packages were stored at $20^{\circ}C$ with periodical measurement of package atmosphere and cake quality attributes. The modified atmosphere packages of 60% $CO_2$/40% $N_2$ and 100% $CO_2$ inhibited the growth of molds/yeasts completely and significantly retarded the growth of aerobic bacteria. All the packages except that of 100% $CO_2$ showed the reduction of internal $O_2$ concentration and increase of the $CO_2$ with storage time due to the microbial activity. There has been slight decrease of $CO_2$ concentration for 60% $CO_2$/40% $N_2$ and 100% $CO_2$ packages just after start of the storage possibly due to dissolution of headspace $CO_2$ into the cake. Any MAP conditions did not affect the retrogradation of the rice cake. Surface color of the cake within affordable microbial quality limit was not affected significantly by packaging conditions.