• Title/Summary/Keyword: 전자침

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Study on Levenberg-Marquardt for Target Motion Analysis (표적기동분석을 위한 Levenberg-Marquardt 적용에 관한 연구)

  • Cho, Sunil
    • Journal of the Institute of Electronics and Information Engineers
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    • v.52 no.8
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    • pp.148-155
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    • 2015
  • The Levenberg-Marquardt method is a well known solution about the least square problem. However, in a Target Motion Analysis(TMA) application most of researches have used the Gauss-Newton method as a batch estimator, which of inverse matrix calculation may causes instability problem. In this paper, Levenberg-Marquardt method is applied to TMA problem to prevent its divergence. In experiment, its performance is compared with Gauss-Newton in domain of range, course and speed. Monte Carlo simulation reveals the convergence time and reliability of the TMA based on Levenberg-Marquardt.

Characterization and preparation titanate nanotubes for Li-ion secondary battery (Li 이차전지용 티타네이트 나노튜브 제조 및 특성평가)

  • Oh, Hyo-Jin;Lee, Nam-Hee;Yoon, Cho-Rong;Jung, Sang-Chul;Kim, Sun-Jae
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2007.11a
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    • pp.510-510
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    • 2007
  • Titanate nanotube(TNT)는 높은 비표면적과 우수한 물리화학적 특성을 가지고 있어 광촉매, 수소 저장재료, 태양전지용 전극재료 등에 적용되고 있다. 또한, 티타네이트 나노튜브는 전자 이동이 원활한 구조적 특징을 가지고 있어 리듐 이차전지용 호스트 재료로서 많은 연구가 진행 중이다. 이에 본 연구에서는 저온균일침전법으로 제조한 루틸상 $TiO_2$ 분말에 Lithium chloride를 1~10wt%를 동시에 첨가한 후 10M의 sodium hydroxide 수용액 내에서 수열합성하여 리튬이 도핑된 티타네이트 나노튜브를 제조하였다. 제조된 분말의 입자형상 및 크기는 전자주사 현미경을 이용하여 관찰하였으며, X-선 회절분석을 이용하여 리튬 첨가에 따른 결정상 변화를 관찰하였다. 또한 리튬이 도핑된 티타네이트 나노튜브의 전기화학적 특성 평가를 위해 양극 활물질 : 도전제 : 바인더를 75 : 20 : 5의 비율로 혼합한 후 coin cell을 제조하였고, potentiostat를 이용하여 용량 측정 및 cycle 특성을 실시하였다. 수열 합성법에 의해 형성된 입자는 직경 10nm, 길이 수 ${\mu}m$로 관찰되었으며, X-선 회절 시험 결과 LiO와 같은 이차상은 발견되지 않았다. 측정된 coin cell의 용량은 240mAh/g을 나타내었으나, 싸이클 특성이 빠르게 저하됨을 확인할 수 있었다.

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Mineralogy and Biogeochemistry of Intertidal Flat Sediment, Muan, Chonnam, Korea (전남 무안 갯벌 퇴적물에 관한 광물학적 및 생지화학적 연구)

  • Park, Byung-No;Lee, Je-Hyun;Oh, Jong-Min;Lee, Seuug-Hee;Han, Ji-Hee;Kim, Yu-Mi;Seo, Hyun-Hee;Roh, Yul
    • Journal of the Mineralogical Society of Korea
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    • v.20 no.1 s.51
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    • pp.47-60
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    • 2007
  • While sedimentological researches on Western coastal tidal flats of Korea have been much pelformed previously, mineralogical and biogeochemical studies are beginning to be studied. The objectives of this study were to investigate mineralogical characteritics of the inter-tidal flat sediments and to explore phase transformation of iron(oxyhydr)oxides and biomineralization by metal-reducing bacteria enriched from the inter-tidal flat sediments from Muan, Jeollanam-do, Korea. Inter-tidal flat sediment samples were collected in Chungkye-myun and Haeje-myun, Muan-gun, Jeollanam-do. Particle size analyses were performed using the pipette method and sedimentation method. The separates including sand, silt and clay fractions were examined by scanning electron microscopy (SEM) with energy dispersive X-ray (EDX) analysis, transmission electron microscopy (TEM), and X-ray diffiaction (XRD). After enriching the metal-.educing bacteria from the into,-tidal flat sediments, the bacteria were used to study phase transformation of the synthesized iron (oxyhydr)oxides and iron biomineralization using lactate or glucose as the electron donors and Fe(III)-containing iron oxides as the electron accepters. Mineralogical studies showed that the sediments of tidal flats in Chung]rye-myun and Haeje-myun consist of quartz, plagioclase, microcline, biotite, kaolinite and illite. Biogeochemical researches showed that the metal-reducing bacteria enriched from the inter-tidal flat sediments reduced reddish brown akaganeite and mineralized nanometer-sized black magnetite. The bacteria also reduced the reddish brown ferrihydrite into black amorphous phases and reduced the yellowish goethite into greenish with formation of nm-sized phases. These results indicate that microbial Fe(III) reduction may play one of important roles in iron and carbon biogeochemistry as well as iron biomineralization in subsurface environments.

Scanning electron microscopic observations of Thezazia callipaeda from human (인체 기생 Thelatria cazlipaeda의 주사전자현미경적 관찰)

  • 최원영;윤지혜
    • Parasites, Hosts and Diseases
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    • v.27 no.3
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    • pp.217-224
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    • 1989
  • Four females and a male nematode isolated from 2 patients who visited eye clinics In Seoul were identified as Thelazia callipaeda and their ultrastructures were observed by scanning electron microscopy(SEM). General features of the worms were slender and attenuated at both ends. Vaginal opening was located at 0.27 mm from the anterior end, and in front of the esophagointestinal junction. In the body cuticle transverse striations varied characteristically through the body. The number of cuticular transverse striations was 400∼650/mm at head portion, 250/mm at middle portion and 300∼350/mm at tail portion. The SEM observation of the mouth part of the females showed 6 cord-like cuticular thickenings in hexagonal arrangement and an amphid was observed. A lateral line, a vaginal opening, a pair of phasmids, and an anus were identified in the body portion. A pair of papillae and 6 cord-like cuticular thickenings were on the mouth part of the male. It was difficult to observe structures at the tail of the male except wrinkle-like structures. Most of the larvae isolated from the uterus of a female worm were sheathed and thus cuticular striations were not Eren. Others were unsheathed and revealed cuticular striations. The oval membrane which encysted sheathed larvae was also observed. These are the 18th and 19th record of human thelaziasis in Korea as the literature are concerned.

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Immunoelectron Microscopic Study on the Nitric Oxide Synthase in Rat Salivary Glands (흰쥐 침샘의 Nitric Oxide Synthase에 관한 면역전자현미경적 연구)

  • Lee, Young-Hwan;Ko, Jeong-Sik;Park, Dae-Kyoon;Park, Kyung-Ho
    • Applied Microscopy
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    • v.38 no.3
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    • pp.221-233
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    • 2008
  • Endogenous nitric oxide (NO) has been known to regulate many physiological and pathological processes, especially the glandular secretion and blood flow. However, nitric oxide synthase (NOS) responsible for NO synthesis has not been well studied ultrastructurally in rat salivary gland. The present study was performed to investigate the distribution of nitric Oxide synthase isoforms (endothelial. neuronal, and inducible NOS). Immunoelectron microscopic study, using monoclonal mouse anti-endothelial NOS, anti-neuronal NOS, and anti-inducible NOS, was performed in the salivary gland of rat. Endothelial NOS (eNOS)-positive immunoreactivities were most prominent in the secretory granules of serous cells of the salivary gland of the rat. Immunoreactivities were well concentrated on serous secretory granules in the serous cells. However, weak eNOS-positive immunoreactivity was observed in the mucous secretory granules of the mucous cells. Positive endothelial NOS (eNOS) immunoreactivities were most prominent in the secretory granules of intralobular ducts. Ductal secretory granules and acinar serous secretory granules have a similar pattern of labeling as eNOS suggestings. Neural NOS (nNOS)-positive immunoreactivity was not detected in duct systems or in acinar cells. Inducible NOS (iNOS)-positive immunoreactivity was not seen in acinar and ductal cells. These results reveal the presence of eNOS in the salivary gland of the rat, which may be related with regulation of the glandular secretion and blood flow through the gland.

Oriental Medical Treatment System Based on Mobile Phone (모바일폰 기반 한방 의료 치료 시스템)

  • Hong, You-Shik;Lee, Sang-Suk;Park, Hyun-Sook;Kim, Han-Gyu
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.14 no.3
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    • pp.199-208
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    • 2014
  • At present, the effect of oriental treatment system is proved in the west and using the data of tongue and pulse of body, the doctor can decide the patient's body state without Xray and CT data of large machines. In this paper, the patient's medical data is transmitted to the doctor and the real time decision algorithm is developed and so the doctor can decide the medical treatments. Using the mobile phone, the pulse data and bio data can be sent to the doctor and therefore the patients, who can't care in real time, can be treated in real time in the impossible medical treatment areas. Therefore in this paper, the oriental medical treatment system algorithm and artificial intelligence electrical needle simulation are processed for real time and checked and treated, so anyone can decide patient's state using mobile phone.

The Partial Discharge Characteristics of the XLPE According to the Tilt of the Needle Electrode (침 전극 기울기에 따른 XLPE의 부분 방전 특성)

  • Shin, Jong-Yeol;Ahn, Byung-Chul;Hong, Jin-Woong
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.28 no.1
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    • pp.28-33
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    • 2015
  • The needle electrode is inserted into the cross-linked polyethylene(XLPE) which is the ultra high voltage cable for electric power. By changing the tilt of the needle electrode, we investigated how the void and the thickness of the insulating layer influence the partial discharge(PD) characteristics and the insulating breakdown. In order to investigate the PD characteristics, The XLPE cable was used to the specimens and the tungsten electrode was used with the needle electrode. And the inner semi-conductive layer material of XLPE cable was used with the negative electrode by bonding with the use of conduction tape. The size of the specimens was manufactured to be $16{\times}40{\times}30[mm^3]$. We confirmed the effect on changing the PD characteristics according to the changing voltage and the tilt of the electrode after applying the voltage on the electrode from 1[kV] to 40[kV] at room temperature. In the PD characteristics, it was confirmed that the PD current of air void specimens with tilt was unstable more than that of no void specimens with tilt. It was also confirmed that the breakdown voltage was decreased because the effect of air void is more active than the change of the needle electrode tilt in the specimen with air void inside the insulation.

A New Error Spreading Method for MPEG Streaming Service Over the Internet (인터넷망에서 MPEG 스트리밍 서비스를 위한 새로운 에러 확산 기법)

  • Pyun, Jae-Young;Shim, Jae-Jeong;Lee, Jae-Yong;Ko, Sung-Jea
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.39 no.5
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    • pp.21-31
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    • 2002
  • As the MPEG streaming traffics are transmitted over the Internet, MPEG packet losses cause error propagation in both spatial and temporal domains which in turn leads to severe degradation in image quality. This image degradation is become worse by the bursty packet loss at the network. In this paper, we propose a new error spreading method to reduce the effects of bursty packet losses over the Internet. The proposed error spreading method spreads out the not utilize packet losses widely, and can be used for videocasting and video-broadcasting that do not utilize the ARQ method. The proposed method can not only reduce the consecutive losses of image blocks, but also improve the performance of error concealment. Experimental results show that the deterioration of MPEG video quality can be reduced by spreading out the MPEG packet losses.

Chemical Compositions and Microscopic observation of White Powder Formed in the Surface of Dried Persimmon (곶감표면에 생성되는 백색분말의 화학조성 및 현미경적 관찰)

  • Moon, Kwang-Deok;Lee, Nak-Hoon;Kim, Jong-Kuk;Kim, Jun-Han
    • Journal of the Korean Society of Food Culture
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    • v.11 no.1
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    • pp.1-5
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    • 1996
  • Chemical composition and microscopic observation of white powder developed in the surface of dried persimmon which produced in several region in Korea were studied. Sugar content in flesh of dried persimmon was $56{\sim}59%$ and composed of glucose and fructose. White powder developed in the surface of dried persimmon was composed of sugar 84.6%, moisture 12.5% and insoluble matter 2.7%, respectively. The major sugar of white powder was glucose with 83.3% and fructose was 16.7%. With scanning electron microscopic obsevation, white powder was seen the shape like a plate, flower, needle and horn, and it was similiar to the shape of recrystalized glucose after hydration. White powder in surface of dried persimmon was seemed that glucose and fructose in flesh were migrated with moisture to drying surface during drying process and glucose was crystalized in the surface of dried persimmon.

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Evaluation of the Clinical Effectiveness of Laser Acupuncture for Disease Specific : Systematic Reviews and Meta-analyses (질환별 레이저 침의 임상적 효과 평가 : 체계적 문헌고찰 및 메타분석)

  • DaeJin Kim;Byunghee Choi;Taeyeung Kim;Sukang Park;Jinyoug Kwak
    • Journal of Biomedical Engineering Research
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    • v.45 no.2
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    • pp.81-89
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    • 2024
  • Purpose : This study conducted a systematic review and meta-analysis to evaluate the clinical effectiveness of laser acupuncture for each condition using information from laser acupuncture trials registered on clinicaltrials.gov from January 2013 to June 2023. Methods : We quantitatively and qualitatively analysed the results of 16 clinical trials of laser acupuncture whose research results were confirmed. A risk of bias assessment was also carried out to assess the quality of each clinical trial. Results : A meta-analysis including three clinical trials was conducted to evaluate the comparative effectiveness of laser acupuncture and sham laser acupuncture in reducing pain and found that the laser acupuncture group had a statistically significant reduction in pain compared with the sham laser acupuncture group. In addition, 11 of the 13 trials not included in the meta-analysis showed a positive effect of laser acupuncture. Conclusion : Although laser acupuncture has a long history of clinical use and a lot of research, there is still some scepticism due to the lack of a clear mechanism of action and inconsistent reports of clinical effectiveness. In addition, there is a significant lack of systematic reviews of clinical evidence for major disease specific, and ongoing research is needed to establish an objective evidence base for the clinical effectiveness of laser acupuncture.