• 제목/요약/키워드: wave treatment

검색결과 567건 처리시간 0.022초

Pico second 기립시간의 충격 전자기파 발생기의 개발 (Development of an Impulse Electromagnetic Wave Generator having Rise time of Pico Second)

  • 김영배;이홍식;정순신
    • 대한전기학회논문지:전기물성ㆍ응용부문C
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    • 제55권12호
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    • pp.597-600
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    • 2006
  • When the energy of the nanoseconds high voltage pulse with hundreds picoseconds of the pulse rise time is emitted into the free space via an antenna, an ultra wide band electromagnetic wave is generated. This electromagnetic wave is expected to be used in transmitting vast amount of informations to far distance, high performance radars, post-packaging pasteurization of food, the detection of underground buried objects, searching of underground water veins or caves, the treatment of waste water or polluted gases and so forth. Additionally, this technology can be used in EMI(electromagnetic interference) evaluation of measuring instruments or printed circuit boards.

여드름 치료를 위한 PWM 기반 광 조사 시스템 설계 (Design of PWM-Based Photo Irradiation System for Acne Treatment)

  • 김창수;임현수
    • 한국방사선학회논문지
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    • 제6권3호
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    • pp.207-215
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    • 2012
  • 광 역학치료(Photodynamic therapy: PDT) 중 하나인 기존의 LED 광 조사는 연속파(Continuous wave: C.W) 방식의 635 nm 파장으로 여드름 치유에 가장 많이 사용되어 왔으나, 이 방식은 에너지효율이 낮고 생체조직에 열이 많이 발생하여 개선의 방안이 필요했다. 본 논문에서는 에너지효율을 높이고 여드름 치료를 위하여 생체조직에서의 열적 파괴현상을 방지하기위해 PWM(펄스 폭 변조: Pulse Width Modulation)을 활용한 여드름 치료용 LED 광 조사장치를 설계하였다. 시스템 구성은 크게 Timer 모듈, PWM 모듈, 광학전달 장치로 크게 세구성하여 설계하였으며, 여드름 치료를 위한 피부 투과 깊이를 높이기 위하여 광학전달 장치는 660 nm 파장의 1 W LED를 사용하였다. PWM 제어를 이용하여 발생된 주파수와 파형을 확인하고, 660 nm LED의 출력에너지 및 생체조직의 표면온도를 확인하여 안정적인 에너지출력과 생체조직의 안정성에 대해 평가하였다. 그 결과 여드름 치료를 위한 660 nm 파장의 1 W LED 광 에너지를 얻기 위하여 C.W 방식으로 사용하였을 경우 전력손실이 높고 생체조직에서의 열적 파괴현상을 보였으나, PWM 방식을 구현함으로써 펄스 폭 변조를 통하여 LED의 전력소모를 낮추었고, 생체조직의 열적 파괴현상이 나타나지 않아 여드름 치료를 위해 사용할 경우 C.W 방식보다 PWM 방식이 더 안전하고 효과적일 것으로 사료된다.

트랜섬 선미 후방의 점성 유동장 Topology 관찰 (Topological View of Viscous Flow behind Transom Stern)

  • 김우전;박일룡
    • 대한조선학회논문집
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    • 제42권4호
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    • pp.322-329
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    • 2005
  • Viscous flows behind transom stern are analyzed based on CFD simulation results. Stern wave pattern is often complicated due to the abrupt change of stern surface curvature and flow separation at transom. When a ship advances at high speed, whole transom stern is exposed out of water, resulting in the so-called 'dry transom'. However, in the moderate speed regime, stern wave development in conjunction of flow separation makes unstable wavy surface partially covering transom surface, i.e., the so-called 'wetted transom'. Transom wave formation is usually affecting the resistance characteristics of a ship, since the pressure contribution on transom surface as well as the wave-making resistance is changed. Flow modeling for 'wetted transom' is difficult, while the 'dry transom modeling' is often applied for the high-speed vessels. In the present study CFD results from the RANS equation solver using a finite volume method with level-set treatment are utilized to assess the topology of transom flow pattern for a destroyer model (DTMB5415) and a container ship (KCS). It is found that transom flow patterns are quite different for the two ships, in conformity to the shape of submerged transom. Furthermore, the existence of free surface seems to after the flow topology in case of KCS.

Effects of Zinc and Its Chelators on ERG b-Wave Sensitivity During the Light Adaptation in Bullfrog Retina

  • Hwang, Kyung-Hee;Kim, Young-Hwal;Park, Jong-Seok
    • 대한임상검사과학회지
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    • 제43권2호
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    • pp.33-42
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    • 2011
  • Zinc plays a key role in genetic expression, cell division, and cell growth and is essential for the functions of more than 450 metalloenzyme. There are high concentrations of zinc in pigment epithelium in bullfrog eye. Zinc deficiency causes night blindness and abnormal dark adaptation. The purpose of this study was to identify ERG (electroretinogram) b-wave sensitivity during light and dark adaptation in bullfrog retina after zinc and zinc chelators treatment such as histidine and TSQ (N-(6-methoxy-8-qunolyl)-p-toluenesulfon amide). Especially, we focused whether histidine act as a zinc chelator in the Muller cell. The results of our study are summarized as follows: 1) Both zinc and histidine elevated ERG b-wave amplitude and threshold in Muller cells by accelerating rhodopsin regeneration time and increased a-peak absorbance during light adaptation. 2) TSQ reduced those by prolonging rhodopsin regeneration time and decrement of a-peak absorbance during light adaptation. 3) Zinc shortened rhodopsin regeneration time and prolonged a-peak absorbance. These results suggested that histidine may act as a zinc-mediated transporter in presynaptic Muller cell membrane rather than zinc chelator and acts as a GABA-receptor inhibitor which blocks $Cl^-$ influx to the postsynapse.

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체외충격파쇄석술을 이용한 총담관 및 췌관 결석의 치료 (Fragmentation of Common Bile Duct and Pancreatic Duct Stones by Extracorporeal Shock-wave Lithotripsy)

  • 김함겸;손순룡;이원홍
    • 대한방사선기술학회지:방사선기술과학
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    • 제21권1호
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    • pp.40-45
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    • 1998
  • To determine its usefulness and safety of extracorporeal shock-wave lithotripsy in common bile duct and pancreatic duct stones, we analyzed the results of 13 patients with common bile duct stones and 6 patients with pancreatic duct stones which were removed by endoscopic procedures using the balloon or basket, who was performed the extracorporeal shock-wave lithotripsy using the ultrasonography for stone localization with a spark gap type Lithotriptor(Dernier MPL 9000, Germany). Fragmentation and complete clearance of the common bile duct and pancreatic duct stones were obtained in 19 of 19 patients(100%). Apart from transient attacks of fever in 2 of 13 patients with common bile duct stones(15%) and mild elevation of serum amylase and lipase in 2 of 6 patients with pancreatic duct stones(33%), no other serious side effects were observed. In our experiences, extracorporeal shock-wave lithotripsy is a safe and useful treatment for endoscopically unretrievable common bile duct and pancreatic duct stones.

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제주도 기후변화 관련 상수도시설 취약성 평가 및 적응대책 (Water utilities vulnerability assessment and adaption strategies for climate change in Jeju province)

  • 김진근
    • 상하수도학회지
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    • 제32권6호
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    • pp.517-526
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    • 2018
  • Climate adaptation strategies for water utilities including 16 water treatment plants(WTPs) in Jeju were investigated. Drought, heat wave, and heavy rain were among the most significant climate factors affecting water utilities in Jeju. Heat wave increases water temperature, which in turn increases the concentration of algae, color, and odor materials. Some adaption strategies for the heat wave can be strengthening water monitoring and introducing advanced water treatments. Heavy rain increases raw water turbidity in surface water. The 7 WTPs that take raw water from streams or springs had a maximum turbidity of less than 50 NTU under heavy rain. However, due to concerns of turbidity spike in treated water, some WTPs discontinued intaking raw water when raw water turbidity increased more than 2 NTU. They instead received treated water from other WTPs which took groundwater for water supply. This happens because of the low skills of employees. Thus, there needs to be an increase in operator competency and upgrade of water facilities for the adaption of heavy rain. To improve adaption for the drought, there should be an increase in the capacity of intake facilities of surface water as well as a decrease in water loss. In addition, water consumption per person should be decreased.

MCU와 나선형 코일을 이용한 촛점식 체외 충격파 전립선 치료 장치에 관한 연구 (The study on Focused Extracorporeal Shock Wave Prostate Therapy Apparatus using MCU and Spiral Coil)

  • 유희수;손병래
    • 한국전자통신학회논문지
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    • 제16권1호
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    • pp.203-210
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    • 2021
  • 만성 전립선 염 치료의 어려움은 치료 의사뿐만 아니라 환자에게도 육체적 고통과 정신적 문제를 유발한다. 본 연구의 장치는 외부 충격파의 열적 및 기계적 상호 작용으로 인한 충격파 에너지의 진동 효과로 인해 전립선 증상으로 고통받는 환자를 돕기 위해 연구되었다. MCU와 나선형코일을 활용하여 집중된 에너지의 열 및 진동 효과를 발생시키고 이 파동을 효과적으로 적용하는 체외 충격파 치료 장치를 고안하여 전립선 염 및 전립선비대증(BPH, Benign prostatic hyperplasia)에 대한 효과적인 치료 수단을 제공하는 구조를 구현하였다.

뇌졸중 후 인지장애의 침 치료에 대한 임상적 연구 고찰 (A Study of Clinical Research Acupuncture Treatment on Post-stroke Cognitive Disorder)

  • 김삼룡;윤종민;문병순
    • 대한한방내과학회지
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    • 제39권3호
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    • pp.389-404
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    • 2018
  • Objective: The aim of this study was to investigate acupuncture therapy for post-stroke cognitive disorder to suggest the methods of a study about acupuncture therapy. Methods: Several academic databases were used in this study, including National Digital Science Library (NDSL), National Assembly Library of Korea, Korean Traditional Knowledge Portal, Research Information Sharing Service (RISS), Korean studies Information Service System (KISS), Korean Medical Database (KMBASE), Korea Med, Oriental Medicine Advanced Searching Integrated System (OASIS), PubMed, MEDLINE with Full Text, and China National Knowledge Infrastructure (CNKI). Keywords used were "중풍", "뇌졸중", "인지장애", "침", "acupuncture", and "cognitive disorder". Results: Ultimately, 28 papers were investigated. that were mainly published in 2012 and 2016. Of these, More than two-thirds received a score of one or less on the Jadad scale. Acupuncture points such as GV20, GV24, PC6, EX-HN1, SP6, and GV26 were most frequently used. The treatment duration was mostly 30 minutes or less, and the treatment cycle was mostly for four weeks. Dilatational wave was generally used in pulse wave form, and amplitude of electricity was increased until patients were able to endure. G6805 was generally used in electric acupuncture apparatus. According to results of acupuncture treatment, assessments such as the MMSE (Mini Mental State Examination) and the Montreal Cognitive Function Assessment Scale (MoCA) showed statistically significant improvements in 28 studies. Conclusions: Future research is needed to standardize the treatment of acupuncture, and more diversified high quality papers should be published to help clarify the therapeutic effects of acupuncture and the mechanisms of cognitive disorder post-stroke.

Alterations of Spontaneous Sleep Architecture and Cortical Electroencephalogram Power Spectra by Red Ginseng Extract via GABAAergic Systems

  • Yang, Shu-Long;Nam, Sang-Yoon;Han, Jin-Yi;Kim, Jun-Cheol;Lee, Ki-Nam;Hong, Jin-Tae;Oh, Ki-Wan;Eun, Jae-Soon
    • Journal of Ginseng Research
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    • 제34권4호
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    • pp.304-313
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    • 2010
  • This study was undertaken to discover the effects and possible mechanisms of the effect of red ginseng extract (RGE) on spontaneous sleep. The effects of a low dose (10 mg/kg) and a high dose (200 mg/kg) of RGE were compared in rats. After recovery from a surgical operation enabling electroencephalograms recordings, rats were administered RGE orally. RGE was administered orally for 1 day or once per day for 5 days in either 10 or 200 mg/kg doses. Polygraphic signs were recorded for 12 h after oral administration of RGE. Both treatment with a large dose (200 mg/kg) of RGE for one day and treatment with either a large or a small dose for 5 days reduced the number of sleep.wake cycles. Daily treatment with RGE (either 10 or 200 mg/kg) for 5 days augmented NREM and total sleep, but reduced wakefulness. Delta wave activity recorded during non-REM (NREM) sleep and REM sleep was increased after one treatment with RGE (either 10 or 200 mg/kg). Delta wave activity during NREM was enhanced after daily treatment with RGE (either 10 or 200 mg/kg) for 5 days. Both alpha and beta subunits of the $\gamma$-aminobutyric acid $(GABA)_A$ receptor were significantly over-expressed in the hypothalamus of the RGE-treated groups. Moreover, the expression of glutamic acid decarboxylase was also increased in the hypothalamus. These results demonstrate that RGE may regulate spontaneous sleep via $GABA_A$ergic systems.

LED 광원이 느티만가닥버섯 균의 균사 생장과 자실체 생육에 미치는 영향 (Effect of LED LightIrradiation on the Mycelial Growth and Fruit Body Development of Hypsizygus Marmoreus)

  • 김민경;이용국;서건식
    • 현장농수산연구지
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    • 제22권1호
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    • pp.99-112
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    • 2020
  • LED 광원이 느티만가닥버섯 재배에 미치는 영향을 알기 위하여 6종의 파장이 다른 NUV(wave length 405nm), blue(wave length 460nm), green(wave length 530nm), yellow(wave length 590 nm), red(wave length 630nm), white(wave length 6500K) 광을 조사하면서 균사 생장 및 자실체 생육과 수량을 조사하였다. 1. 느티만가닥버섯균의 균사 생장에는 광이 필요하지 않지만, red 광 처리구에서 암조건과 비슷한 균사 생장을 보였다. 그러나 blue, green, yellow 광 처리구에서는 암배양보다 약 30~40%의 균사 생장 저해를 보였다. 2. LED 광이 느티만가닥버섯의 자실체 생육에 미치는 영향을 조사한 결과, 암조건에서는 자실체 발달이 안 되는 경우도 있으므로, 느티만가닥버섯의 자실체 생육에는 광 조사가 꼭 필요하다. 단파장인 blue와 green광, 복합광인 white을 조사한 처리구에서 자실체 갓과 대 발달이 안정적이면서 수량이 우수하였다. 장파장인 red 와 yellow 광 처리구에서는 갓 발달과 색택이 불량하고, 대는 길고 꼬임 등의 기형을 보였다. 3. 단일광 조사만으로는 우수한 품질의 버섯을 안정적으로 생산하기 어렵고, 각 생육 단계마다 효과가 있는 광을 조사하는 것도 어렵다. blue와 green, white, red 광을 조합하여 생육 기간 동안 혼합광을 조사하여 갓과 대의 균일성 및 갓 색택, 수량을 분석한 결과, 가장 이상적인 LED 광 조합은 blue와 white 광이었다.