• Title/Summary/Keyword: Characteristic function

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A Clinical Trial of Light Therapy on Patients with Premenstrual Dysphoric Disorder (월경전 불쾌기분장애 환자의 광치료 임상 시도)

  • Joe, Sook-Haeng;Kim, Jin-Se;Kim, Seung-Hyun;Kim, Leen
    • Sleep Medicine and Psychophysiology
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    • v.6 no.1
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    • pp.46-51
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    • 1999
  • Objectives: Patients with premenstrual dysphoric disorder(or PMDD) have impairments of the social, occupational or academic function due to psychological or somatic symptoms, which have the characteristic pattern of symptom exacerbation in the week before menses begin and remission shortly after the onset of menses. In the chronobiological view, many researchers have assumed that the etiology of PMDD is the advanced circadian rhythm. It has been suggested that light has a therapeutic effect on PMDD, because evening light results in phase delay of circadian rhythm through the biochemical changes including melatonin. Methods: The authors investigated the therapeutic effect of light therapy on four patients with prospectively diagnosed PMDD by DSM-IV criteria using clinical psychiatric interview, Premenstrual Assessment Form(PAF) and Daily Rating Form(or DRF). In the evening(6:30pm-8:00pm), the 2,500 lux light administered for seven consecutive days during the symptomatic late luteal phase of menstrual cycle. Beck Depression Inventory(or BDI), Hamilton Rating Scale for Depression(or HAM-D), Spielberg State Anxiety Inventory(or SA), and DRF were evaluated before and after seven days of light therapy. Results: Premenstrual symptoms of PMDD could be effectively treated with the evening bright light therapy, especially in PMDD patients with atypical symptoms. In addition, the light therapy seemed to more effective on the psychologic symptoms than the somatic symptoms of PMDD. There was no significant side-effect of light therapy, except the transient and mild eye-strain in one case. Conclusions: In spite of the results of limited data from our clinical trial, the authors suggest that the potential use of light therapy as an alternative to the pharmacological management of patients with PMDD.

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Intelligent Tuning of the Two Degrees-of-Freedom Proportional-Integral-Derivative Controller On the Distributed Control System for Steam Temperature Control of Thermal Power Plant

  • Dong Hwa Kim;Won Pyo Hong;Seung Hack Lee
    • KIEE International Transaction on Systems and Control
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    • v.2D no.2
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    • pp.78-91
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    • 2002
  • In the thermal power plant, there are six manipulated variables: main steam flow, feedwater flow, fuel flow, air flow, spray flow, and gas recirculation flow. There are five controlled variables: generator output, main steam pressure, main steam temperature, exhaust gas density, and reheater steam temperature. Therefore, the thermal power plant control system is a multinput and output system. In the control system, the main steam temperature is typically regulated by the fuel flow rate and the spray flow rate, and the reheater steam temperature is regulated by the gas recirculation flow rate. However, strict control of the steam temperature must be maintained to avoid thermal stress. Maintaining the steam temperature can be difficult due to heating value variation to the fuel source, time delay changes in the main steam temperature versus changes in fuel flow rate, difficulty of control of the main steam temperature control and the reheater steam temperature control system owing to the dynamic response characteristics of changes in steam temperature and the reheater steam temperature, and the fluctuation of inner fluid water and steam flow rates during the load-following operation. Up to the present time, the Proportional-Integral-Derivative Controller has been used to operate this system. However, it is very difficult to achieve an optimal PID gain with no experience, since the gain of the PID controller has to be manually tuned by trial and error. This paper focuses on the characteristic comparison of the PID controller and the modified 2-DOF PID Controller (Two-Degrees-Freedom Proportional-Integral-Derivative) on the DCS (Distributed Control System). The method is to design an optimal controller that can be operated on the thermal generating plant in Seoul, Korea. The modified 2-DOF PID controller is designed to enable parameters to fit into the thermal plant during disturbances. To attain an optimal control method, transfer function and operating data from start-up, running, and stop procedures of the thermal plant have been acquired. Through this research, the stable range of a 2-DOF parameter for only this system could be found for the start-up procedure and this parameter could be used for the tuning problem. Also, this paper addressed whether an intelligent tuning method based on immune network algorithms can be used effectively in tuning these controllers.

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Wind-sand coupling movement induced by strong typhoon and its influences on aerodynamic force distribution of the wind turbine

  • Ke, Shitang;Dong, Yifan;Zhu, Rongkuan;Wang, Tongguang
    • Wind and Structures
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    • v.30 no.4
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    • pp.433-450
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    • 2020
  • The strong turbulence characteristic of typhoon not only will significantly change flow field characteristics surrounding the large-scale wind turbine and aerodynamic force distribution on surface, but also may cause morphological evolution of coast dune and thereby form sand storms. A 5MW horizontal-axis wind turbine in a wind power plant of southeastern coastal areas in China was chosen to investigate the distribution law of additional loads caused by wind-sand coupling movement of coast dune at landing of strong typhoons. Firstly, a mesoscale Weather Research and Forecasting (WRF) mode was introduced in for high spatial resolution simulation of typhoon "Megi". Wind speed profile on the boundary layer of typhoon was gained through fitting based on nonlinear least squares and then it was integrated into the user-defined function (UDF) as an entry condition of small-scaled CFD numerical simulation. On this basis, a synchronous iterative modeling of wind field and sand particle combination was carried out by using a continuous phase and discrete phase. Influencing laws of typhoon and normal wind on moving characteristics of sand particles, equivalent pressure distribution mode of structural surface and characteristics of lift resistance coefficient were compared. Results demonstrated that: Compared with normal wind, mesoscale typhoon intensifies the 3D aerodynamic distribution mode on structural surface of wind turbine significantly. Different from wind loads, sand loads mainly impact on 30° ranges at two sides of the lower windward region on the tower. The ratio between sand loads and wind load reaches 3.937% and the maximum sand pressure coefficient is 0.09. The coupling impact effect of strong typhoon and large sand particles is more significant, in which the resistance coefficient of tower is increased by 9.80% to the maximum extent. The maximum resistance coefficient in typhoon field is 13.79% higher than that in the normal wind field.

A Comparative Study of the Korean and Manchurian Railway Systems during the Japan Colonial Period (일제강점기의 한국철도와 만주철도의 비교연구)

  • Lee, Yongsang;Chung, Byunghyun
    • Journal of the Korean Society for Railway
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    • v.16 no.2
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    • pp.151-162
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    • 2013
  • This paper presents a comparison of Korean and Manchurian railway system during the Japanese colonial era of Korea. While both railways share the common characteristics of an imperial railway, they revealed several differences. Firstly, the Manchurian railway was likely a private company, although it was operated half privately and half by the government. The Manchurian railway operated like the East Indian Company in India during the English colonial era. On the other hand, the Korean railway was fully operated by the government at a ministry level. While the Korean railway solely concentrated on the railway, the Manchurian railway was involved in regional development and the coal-mining industry as well. Secondly, in contrast to the Korean railway, the Manchurian railway was more lucrative, and was relatively more predominant regarding carriage of freights. Thirdly, railway officers in Korea were elected government bureaucrats, while Manchurian railway officers came from diverse political parties and social strata. After the annexation by the Kwantung Army, the Manchurian railway was mainly influenced by the military. The common characteristic here was that both railways were utilized for military purposes as imperial railways. In partilcular, the Manchurian railway executed military orders directly. Hereafter, through a comparative study between the Japanese and Taiwanese railways, a clear and accurate understanding of the characteristics of the Korean railway during the Japanese era will be revealed.

A Study on the Visual Expression of the Characters for the Narrative in Animation - A Focus on Skeleton Character in "Coco(2017)" by Pixar - (장편 애니메이션 내러티브를 위한 캐릭터의 시각적 표현에 관한 연구 -픽사(PIXAR) "코코(2017)"의 해골 캐릭터를 중심으로-)

  • Kim, Soong-Hyun
    • Journal of Digital Convergence
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    • v.17 no.12
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    • pp.451-459
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    • 2019
  • This study is aims to examine how the skeleton character in Pixar's Animation is visualized for the narrative of the film and suggests the direction of attractive character development corresponding to the story. First of all, it was conducted the case studies on the narrative of animation, character design, character's emotion expression, and animations featuring skeleton character. Based on this study, it was derived the visual representation of the skeleton character featuring in and analyzed the role and function in the animation. As a result, the expressions by the skeleton's eyes, eyebrows, mouth, lips, and jaw played the most important role for the emotional expression and lines in , and the major characteristic for human facial expression was reflected in the design of the skeleton character. In addition, the various props were used to provide the detailed informations of the skeleton's character, and it was expressed the movement emphasizing its essential attribute. Finally, the skeleton's symbolic image was strengthened by composing and arranging the skeleton's image through Mise en scene. It is expected that this study will be used as a reference for the animation character related researchers and practitioners in the business and it helps develop attractive characters fir the narrative animation in the future.

External Morphology of the American Leafminer, Liriomyza trifolii (Diptera: Agromyzidae), on Tomato with Scanning Electron Microscope (주사전자현미경을 이용한 토마토에 발생하는 아메리카잎굴파리(Liriomyza trifolii)의 외부형태적 특징)

  • Youn, Young-Nam;Kim, Ki-Duck;Park, Su-Jin;Kim, Nam-Sung;Seo, Mi-Ja;Chae, Soon-Yong
    • Korean Journal of Agricultural Science
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    • v.27 no.1
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    • pp.13-19
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    • 2000
  • The external morphology of male and female of Liriomyza trifolii (Burgess) was studied using the scanning electron microscopy (SEM). Three types of sensilla were identified on the funicle of antennae. The trichoid sensilla were most conspicious and distributed with a characteristic sharp structure at the apical end. Basiconic sensilla were showed distal curvature about $13{\mu}m$ long and $1.2{\mu}m$ to $1.4{\mu}m$ in diameter. Grooved sensilla were showed a finger-like projections at the peg apex. The function of these sensilla likely to be olfactory. The mouthparts were adapted for sucking food, and formed a elongate rostrum which was incorporated with labrum. The labrum was a small and flap-like shape. The slender and paired maxillary palp seemed to combine with each other lengthwise to long tube. The tarsus typically consisted of 5 segments, which might be variously modified, principally by thickening or flattening. The segment beared a pair of claws. Beneath the claws, there was a pair of pad-like pulvillia and a bristle-like median empodium. L. trifolii might secreted on the pulvillus and empodium an adhesive substance that enable them to cling to smooth surfaces. Male terminalia was complicated. The name 'aedeagus' seemed the best available general term for the copulatory organ, otherwise, female terminalia was usually relatively simple. This structure was reduced and formed a telescopic, eversible, and tubular ovipositor.

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Interstitial Lung Disease Associated with Polymyositis: Response to Cyclophosphamide and Prednisolone Combination Treatment (Cyclophosphamide와 Prednisolone 병합요법에 치료반응을 보인 다발성근염에 동반된 간질성폐질환 1예)

  • Moon, Jong-Ho;Park, Jun-Young;Lee, Sang-Moo;Kim, Hyeon-Tae;Uh, Soo-Taek;Chung, Yeon-Tae;Kim, Yong-Hoon;Park, Choon-Sik;Lee, Kyung-Soo;Kang, Dae-Young
    • Tuberculosis and Respiratory Diseases
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    • v.40 no.2
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    • pp.197-202
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    • 1993
  • Polymyositis (PM) is a inflammatory connective tissue disease involving predominantly skeletal muscles, characterized by symmetrical, proximal muscle weakness, inflammation, and frequently, degeneration. Interstitial lung disease in association with PM occurs in 5~10% of cases and carries an especially grave prognosis. Although the cause of lung involvement in PM is not known, the underlying pathologic process in the lung is an immune mediated inflammation of alveolar structures, alveolitis. It is of interest, therefore, that cyclophosphamide, an immune modulating agent, has been reported to be effective in the treatment of PM. We report a case of corticosteroid resistant PM associated with interstitial lung disease, successfully treated with cyclophosphamide. A 37-year-old female was presented with 8 months duration of cough, exertional dyspnea, and muscle weakness. She had typical symptoms, physical findings, and elevated muscle enzyme levels in serum with characteristic findings of muscle biopsy. She also had typical interstitial lung disease pattern on chest X-ray and high resolution CT with restrictive pattern on pulmonary function test. The findings of transbronchial lung biopsy was compatible with interstitial lung disease. She failed to respond to corticosteroid initially. Subsequently steroids and cyclophosphamide were given with excellent clinical improvement.

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The Surface Characteristic Changes of Hydroxyapatite Coated Ti Disc When Immersed in NaCl Solution (NaCl 수용액에 담근 Hydroxyapatite 코팅된 타이타늄 시편의 표면 변화)

  • Baek, Yeon-Wha;Kim, Myung-Joo;Kwon, Ho-Beom;Lim, Young-Jun
    • Journal of Dental Rehabilitation and Applied Science
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    • v.28 no.4
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    • pp.339-347
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    • 2012
  • In previous studies, methods for enhancing cellular response on the Hydroxyapatite coated implant surface were described. In this study, the changes of surface characteristics such as surface roughness, contact angle, surface energy and surface morphology were observed when Hydroxyapatite coated Ti discs were immersed in NaCl solution for various time. Hydroxyapatite coated Ti discs were immersed in 0.9% NaCl solution for 7, 14 and 21 days at $37^{\circ}C$. The control group comprises dry identical discs not immersed in a solution. (n=3) All discs were dried in air completely and the surface roughness was measured using confocal laser scanning microscopy(CLSM). Static contact angle was recorded by video contact angle analyzer after dropping distilled water on the surface. The surface energy was calculated from contact angles of the three liquids. Surface was observed using a field emission-scanning electron microscope(FE-SEM). As a result, the surface roughness of immersed Hydroxyapatite coated Ti discs increased significantly and the contact angle decreased comparing with control group discs. The surface energy of immersed discs increased except for discs immersed for 14 days.

Experimental Observation of Instability of Supersonic Submerged Jets (수중초음속제트의 불안정성에 대한 실험적 고찰)

  • 정재권;이대훈;차홍석;박승오;권세진
    • Journal of the Korean Society of Propulsion Engineers
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    • v.6 no.2
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    • pp.45-52
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    • 2002
  • An experimental investigation on the structure and dynamic behavior of two dimensional over-expanded air jets exiting into water was carried out. The hish speed digital video imaging and static pressure distribution measurement were made to characterize the structure and time-dependant behavior of the jets. Mach number at the jet exit was 2.0 and was slightly less than the value predicted by the ideal nozzle calculation. Variance of jet spreading angle at different stagnation condition was measured as a function of mass flow rate. Periodic nature of the air jet distortion in water was observed and the frequency of the repetition was approximately 5-6 Hz for all cases tested. Three characteristic length scales were defined to characterize jet structure. $L_1$, maximum width of the plume when the periodic instability occurs, $L_2$, width of the jet where secondary reverse flow entrained jet flow and $L_3$, distance from the jet exit to the location where entrainment of the secondary reverse flow occurs. The ratio of $L_1$ and $L_2$ decreased with increasing stagnation pressure, i.e. mass flow rate. $L_3$ increased with increasing stagnation pressure. The temporal behavior of static pressure measurements also showed peak around frequency of 5, which corresponds the frequency obtained by visual measurements

8 Cases of Partial Laryngectomy (최근 경험한 후두부분절제술 8예)

  • 유홍균;김명진;이상학;신홍수
    • Proceedings of the KOR-BRONCHOESO Conference
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    • 1983.05a
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    • pp.14.4-15
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    • 1983
  • The laryngeal carcinoma is the most frequent malignant tumor in the E.N.T. field. In the surgical treatment of laryngeal carcinoma, in 1873, Billroth performed the first total laryngectomy, and in 1863, H. B. Sands performed the first partial laryngectomy. Recently general advances (antibiotic therapy, blood trasfusion, and safer anesthesia) result in the improvement of postoperative prognosis. Because the laryngeal lymphatic system has the characteristic compartmentation, this serves the anatomic basis for performing the partial laryngectomy. Although the indications of partial laryngectomy are different from that of total laryngectomy, the partial laryngectomy has the advantage of not only removal of all malignant disease, but also maximum preservation of respiratory, phonatory, and sphincteric function of the larynx. In the latest, surgical treatment decreased the frequency of recurrence, and also increased the 5 year survival rate with combination of the chemotherapy and radiation therapy. The authors have experienced 8 cases of partial laryngectomy for laryngeal carcinoma at the department of otolaryngology, Korea University Hospital from 1980 to 1982. Among the total 8 cases, 2 cases were involved only in the epiglottis, 2 cases in the anterior 1/3 of both vocal cords with ant. comissure, 2 cases in the middle 1/3 of Lt. vocal cord, 1 case in the anterior 1/3 of Rt. vocal cord with ant. comissure, and another 1 case in the Rt. ventrical. So authors report these cases with review of the literature.

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