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The Optimal Distribution Feeder Reconfiguration Using Knowledge Base (지식베이스를 이용한 배전계통의 최적재구성)

  • Cho, S.H.;Choi, B.Y.;Kim, S.H.;Lee, J.K.
    • Proceedings of the KIEE Conference
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    • 1993.07a
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    • pp.99-101
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    • 1993
  • This paper presents an approach to feeder reconfiguration in order to achieve an efficient operation of distribution systems utilizing knowledge base. The optimal feeder reconfiguration in this study eliminates various abnormal states which will create feeder overloads and feeder constraint problems. and will also accomplish minimum power loss of the distribution systems under normal operating condition by means of branch exchanges to change the status of sectionalizing switches with experiences of the experts. For an effective implementation of feeder reconfiguration, a best-first tree searching strategy based on heuristics is employed to evaluate the various alternatives of load transfer. The heuristic exchange of branches results in reduction of the search space as a means of implementing the best-first searching strategy.

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Load Dispatching Control of Multiple-Parallel-Converters Rectifier to Maximize Conversion Efficiency

  • Orihara, Dai;Saitoh, Hiroumi;Higuchi, Yuji;Babasaki, Tadatoshi
    • Journal of Electrical Engineering and Technology
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    • v.9 no.3
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    • pp.1132-1136
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    • 2014
  • In the context of increasing electric energy consumption in a data center, energy efficiency improvement is strongly emphasized. In a data center, electric energy is largely consumed by DC power supply system, which is based on a rectifier composed by multiple parallel converters. Therefore, rectifier efficiency must be improved for minimizing loss of DC power supply system. Rectifier efficiency can be modulated by load allocation to converters because converter efficiency depends on input AC power. In this paper, we propose a new control method to maximize rectifier efficiency. The method can control load allocation to converters by introducing active power converter control scheme and start-and-stop of converters. In order to illustrate optimal load allocations in a rectifier, a maximization problem of rectifier efficiency is formulated as a nonlinear optimization one. The problem is solved by Lagrangian relaxation method and the computation results provide the validity of proposed method.

Analysis of transformer sheet winding losses and temperature rise (변압기 sheet권선 손실 및 온도 상승 해석)

  • Kim, Ji-Hyun;Kim, Young-Man;Ro, Kyoung-Chul
    • Proceedings of the KIEE Conference
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    • 2005.10c
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    • pp.23-25
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    • 2005
  • This paper describes analysis of transformer sheet winding losses and temperature rise. Sheet windings are used if transformer rating currents are so high that one meets current density limit on windings. Unlike stranded windings, sheet windings may be locally healed due to R direction flux. Winding losses with eddy current effect are calculated by finite element electromagnetic analysis and temperature rise is also calculated by Computational Fluid Dynamics (CFD) with loss result.

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Nephrolithiasis in an Aged Snow Leopard

  • Eo, Kyung-Yeon;Lee, Hyun-Ho;Jung, Young-Mok;Kwon, Oh-Deog
    • Journal of Veterinary Clinics
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    • v.33 no.5
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    • pp.313-315
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    • 2016
  • An aged (14 years old) female snow leopard exhibited renal calculi and pyelonephritis at necropsy. The animal experienced appetite loss, mild diarrhea, polydipsia, and difficulty breathing, and was curled up and staggering on its hind legs 2 days before death. Large calculi were found obstructing both sides of the renal pelvis. The left-side calculus was larger than that of the right side. These calculi had rough surfaces and were $15{\times}21mm$ and $9{\times}14mm$, respectively. The bladder was filled with dark, cloudy urine. Multiple ulcerous lesions were found in the inner layer of the bladder. Enterococcus faecalis and Proteus mirabili were identified via microbiological examination of the urine. Under microscopic examination, urine struvites were observed in the pyuria sediment in the bladder. To our knowledge, this is the first documented case of nephrolithiasis in a captive snow leopard.

TERATOGENICITY STUDY OF RECOMBINANT GRANULOCYTE-MACROPHAGE COLONY STIMULATING FACTOR (LBD-005) IN RABBITS

  • Chung, Moon-Koo;Han, Sang-Seop;Roh, Jung-Koo
    • Toxicological Research
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    • v.9 no.1
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    • pp.61-67
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    • 1993
  • LBD-005, a newly developed recombinant granulocyte-macrophage colony-stimulating factor, was at dose levels of 0, 20, 80 and 320ng/kg/day administered subcutaneously to pregnat New Zealand White rabbits during the organogenetic period. The dams were subjected to caesarean section on day 28 of pregnancy. Effects of test substance on dams and embryonal development of fetuses were examined. No treatment-related changes in clinical signs and necropsy findings of dams were observed in all groups. At 80 and 320 ng/kg, a significant decrease in food consumption followed by a loss in body weight was found.

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Novel Raman Fiber Laser and Fiber-Optic Sensors Using Multi-Channel Fiber Gratings

  • Han, Young-Geun;Kim, Sang-Hyuck;Lee, Sang-Bae;Kim, Chang-Seok;Kang, Jin-U.;Paek, Un-Chul;Chung, Young-Joo
    • Journal of the Optical Society of Korea
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    • v.7 no.2
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    • pp.97-101
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    • 2003
  • The transmission characteristics of multi-channel long period fiber gratings (LPFGs) in terms of the physical parameters like the separation distance, grating length and number of gratings will be discussed. Their transmission characteristics such as channel spacing, number of channels, loss peak depth, and channel bandwidth can be easily controlled by physical parameters. Based on the experimental results, their applications to optical multiwavelength Raman lasers and optical sensors will be investigated. A multiwavelength Raman fiber ring laser with 9 WDM channels with 100 ㎓ spacing and 19 channels with 50 ㎓ spacing using tunable multi-channel LPFGs will be experimentally demonstrated. The fiber-optic sensing applications with high resolution and sensitivity based on multi-channel LPFGs will be also presented.

Sarcopenia targeting with autophagy mechanism by exercise

  • Park, Sung Sup;Seo, Young-Kyo;Kwon, Ki-Sun
    • BMB Reports
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    • v.52 no.1
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    • pp.64-69
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    • 2019
  • The loss of skeletal muscle, called sarcopenia, is an inevitable event during the aging process, and significantly impacts quality of life. Autophagy is known to reduce muscle atrophy caused by dysfunctional organelles, even though the molecular mechanism remains unclear. Here, we have discuss the current understanding of exercise-induced autophagy activation in skeletal muscle regeneration and remodeling, leading to sarcopenia intervention. With aging, dysregulation of autophagy flux inhibits lysosomal storage processes involved in muscle biogenesis. AMPK-ULK1 and the $FoxO/PGC-1{\alpha}$ signaling pathways play a critical role in the induction of autophagy machinery in skeletal muscle, thus these pathways could be targets for therapeutics development. Autophagy has been also shown to be a critical regulator of stem cell fate, which determines satellite cell differentiation into muscle fiber, thereby increasing muscle mass. This review aims to provide a comprehensive understanding of the physiological role of autophagy in skeletal muscle aging and sarcopenia.

Transient global amnesia associated with multiple lesions in the corpus callosum and hippocampus

  • Kim, Jin-Ah;Min, Young Gi;Koo, Dae Lim
    • Annals of Clinical Neurophysiology
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    • v.21 no.2
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    • pp.102-104
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    • 2019
  • Transient global amnesia is a syndrome of temporary loss of short-term memory and is not accompanied by any other neurological deficit. Diffusion-weighted imaging is useful to improve the diagnostic accuracy of transient global amnesia. We report a 68-year-old woman with multiple lesions on diffusion-weighted imaging in the right corpus callosum and left hippocampus. To the best of our knowledge, this is the first case of a diffusion-weighted imaging lesion in the body portion of the corpus callosum.

Palmar-plantar erythrodysesthesia syndrome resulting from toceranib phosphate in a dog with apocrine gland anal sac adenocarcinoma: a case report

  • Eunjoo Kim ;Sung-Soo Kim ;Min-Ok Ryu
    • Journal of Veterinary Science
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    • v.24 no.6
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    • pp.76.1-76.6
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    • 2023
  • An 11-year-old neutered male Miniature Poodle with a stage 3 apocrine gland adenocarcinoma was started on chemotherapy with toceranib phosphate after surgery. Beginning on day 10 of toceranib, the dog's foot pads became erythematous and hyperkeratinized. The dog complained of pain, inability to walk, depression, and loss of appetite. The symptoms resolved when toceranib was discontinued and reappeared when toceranib was resumed. Grade 3 palmar-plantar erythrodysesthesia was identified as an adverse event of toceranib based on the VCOG-CTCAE and Naranjo scale. Although very rare in veterinary medicine, clinicians should consider that palmar-plantar erythrodysesthesia can occur after toceranib administration.

Construction and Validation of Hospital-Based Cancer Registry Using Various Health Records to Detect Patients with Newly Diagnosed Cancer: Experience at Asan Medical Center (의무기록의 다각적 활용을 통한 충실도 높은 병원 암등록 체계의 구축: 서울아산병원의 경험)

  • Kim, Hwa-Jung;Cho, Jin-Hee;Lyu, Yong-Man;Lee, Sun-Hye;Hwang, Kyeong-Ha;Lee, Moo-Song
    • Journal of Preventive Medicine and Public Health
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    • v.43 no.3
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    • pp.257-264
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    • 2010
  • Objectives: An accurate estimation of cancer patients is the basis of epidemiological studies and health services. However in Korea, cancer patients visiting out-patient clinics are usually ruled out of such studies and so these studies are suspected of underestimating the cancer patient population. The purpose of this study is to construct a more complete, hospital-based cancer patient registry using multiple sources of medical information. Methods: We constructed a cancer patient detection algorithm using records from various sources that were obtained from both the in-patients and out-patients seen at Asan Medical Center (AMC) for any reason. The medical data from the potentially incident cancer patients was reviewed four months after first being detected by the algorithm to determine whether these patients actually did or did not have cancer. Results: Besides the traditional practice of reviewing the charts of in-patients upon their discharge, five more sources of information were added for this algorithm, i.e., pathology reports, the national severe disease registry, the reason for treatment, prescriptions of chemotherapeutic agents and radiation therapy reports. The constructed algorithm was observed to have a PPV of 87.04%. Compared to the results of traditional practice, 36.8% of registry failures were avoided using the AMC algorithm. Conclusions: To minimize loss in the cancer registry, various data sources should be utilized, and the AMC algorithm can be a successful model for this. Further research will be required in order to apply novel and innovative technology to the electronic medical records system in order to generate new signals from data that has not been previously used.