• Title/Summary/Keyword: internal control method

Search Result 1,209, Processing Time 0.03 seconds

Late Vascular Complication after Mandibular Ramus Sagittal Split Osteotomy: A Case Report (하악지 시상 분리 절골술 후 발생한 후기 혈관성 합병증의 치험례)

  • Nam, Doo Huyn;Tark, Min Seong;Kim, Cheol Hann;Kang, Sang Gyu;Lee, Yung Man;Park, Sung Tae
    • Archives of Plastic Surgery
    • /
    • v.34 no.1
    • /
    • pp.137-139
    • /
    • 2007
  • Purpose: The mandibular ramus sagittal split osteotomy is a common procedure in cosmetic surgery. A late complication of this procedure, pseudoaneurysm rarely happens. The purpose of this case is to present our experience that is rare late vascular complication after mandibular ramus sagittal split osteotomy. Methods: A 21-year-old male was operated by local plastic surgeon for treatment of mandibular prognathism. After 9 days, the man was transferred to our hospital with persistent bleeding and swelling on the mandibular area. We operated the man three times and failed to control hemorrhage. Therefore, we did angiography and found the pseudoaneurysm on the buccal and pterygoid branches of internal maxillary artery. Then we did selective embolization for removal of the pseudoaneurysm. Results: The man was operated using the therapeutic embolization, and the pseudoaneurysm was removed. The results were successful, and we couldn't find any bleeding and the pseudoaneurysm during the follow-up of 12 months. Conclusion: The selective embolization is the good therapeutic method of late vascular complication after mandibular ramus sagittal split osteotomy.

The Education Program Model for the Thinking Extension Ability of the Gifted in Information Based on Game Tree (게임 트리에 기반한 정보영재의 사고력 신장을 위한 교육 프로그램 모형)

  • Jung, Deok-Gil;Kim, Byung-Joe
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.11 no.6
    • /
    • pp.1228-1234
    • /
    • 2007
  • In this paper, we develop the thinking extension education program for the gifted students of information and prove the validity and effectiveness of the proposed model by presenting the Tic-tac-toe problem as the practical example of the information-gifted students. This model consists of four phases which has the game tree as data structure and the search of game lee as control structure. And the search of game tree becomes the basis of the thinking extension education program. This model gives the help for students to learn representing the problem as tree structure and solving the problem of tree structure using the search method of game tree. The internal ability of the information-gifted for thinking extension of this education program contains the fluency, perceptiveness, originality, power of concentration, imaginative power, analyzing skills, pattern recognition, space sense, synthesizing, problem-solving.

Effects of macroporosity and double porosity on noise control of acoustic cavity

  • Sujatha, C.;Kore, Shantanu S.
    • Advances in aircraft and spacecraft science
    • /
    • v.3 no.3
    • /
    • pp.351-366
    • /
    • 2016
  • Macroperforations improve the sound absorption performance of porous materials in acoustic cavities and in waveguides. In an acoustic cavity, enhanced noise reduction is achieved using porous materials having macroperforations. Double porosity materials are obtained by filling these macroperforations with different poroelastic materials having distinct physical properties. The locations of macroperforations in porous layers can be chosen based on cavity mode shapes. In this paper, the effect of variation of macroporosity and double porosity in porous materials on noise reduction in an acoustic cavity is presented. This analysis is done keeping each perforation size constant. Macroporosity of a porous material is the fraction of area covered by macro holes over the entire porous layer. The number of macroperforations decides macroporosity value. The system under investigation is an acoustic cavity having a layer of poroelastic material rigidly attached on one side and excited by an internal point source. The overall sound pressure level (SPL) inside the cavity coupled with porous layer is calculated using mixed displacement-pressure finite element formulation based on Biot-Allard theory. A 32 node, cubic polynomial brick element is used for discretization of both the cavity and the porous layer. The overall SPL in the cavity lined with porous layer is calculated for various macroporosities ranging from 0.05 to 0.4. The results show that variation in macroporosity of the porous layer affects the overall SPL inside the cavity. This variation in macroporosity is based on the cavity mode shapes. The optimum range of macroporosities in poroelastic layer is determined from this analysis. Next, SPL is calculated considering periodic and nodal line based optimum macroporosity. The corresponding results show that locations of macroperforations based on mode shapes of the acoustic cavity yield better noise reduction compared to those based on nodal lines or periodic macroperforations in poroelastic material layer. Finally, the effectiveness of double porosity materials in terms of overall sound pressure level, compared to equivolume double layer poroelastic materials is investigated; for this the double porosity material is obtained by filling the macroperforations based on mode shapes of the acoustic cavity.

Effects of Anti-ecotoxicological Curcumin Nanospheres on Feed Efficiency and Fecal Odor in Mice (환경 독성 억제효과를 가진 커큐민 나노스피어가 마우스의 사료 효율 및 악취저감에 미치는 영향)

  • Park, Jeong-Bae;Lee, Young-Min;Park, Moon-Ki;Min, Taesun;Lee, Sei-Jung
    • Journal of Environmental Science International
    • /
    • v.28 no.2
    • /
    • pp.183-189
    • /
    • 2019
  • Curcumin ($C_{21}H_{20}O_6$) is a hydrophobic polyphenol found in turmeric. Although curcumin has been used as a natural medicine, its major limitation is related to poor absorption from the gut. Therefore, we developed a method for preparation of Curcumin Nanospheres (CN) to improve the aqueous-phase solubility of curcumin and investigate the functional role of CN in promoting feed efficiency and odor reduction in mice. CN showed inhibitory effects on actate dehydrogenase (LDH) cytotoxicity induced by ecotoxic substance toluene in gut epithelial HCT116 cells. In addition, the weights of internal organs (liver, heart, kidneys, and spleen) and the levels of serum Glutamate Oxaloacetate Transaminase (GOT), Glutamate Pyruvate Transaminase (GPT), and LDH did not show significant differences between mice administered oral CN for two weeks and compared to the control group. Interestingly, CN not only reduced hydrogen sulfide ($H_2S$) and ammonia ($NH_3$) levels and fecal odor, but also improved feed efficiency in mice. These results demonstrate that oral nano-delivery of anti-ecotoxicological CN is a functional system to deliver curcumin to the gut to improve feed efficiency and reduce fecal odor in mice.

Comparison of Practical Usefulness of Respirational Radiation Treatment Using Geant 4 Simulation Code (Geant 4 시뮬레이션 코드를 이용한 호흡 동조 방사선치료의 유용성 비교)

  • Jang, Eun-Sung;Lee, Hyo-Yeong
    • Journal of the Korean Society of Radiology
    • /
    • v.13 no.4
    • /
    • pp.637-643
    • /
    • 2019
  • To verify internal movements of the body, a DICOM file obtained from CT and a Geant4 code were used to simulate lung cancer patients. In addition, the method is applied to measure the movement of tumor when the movement of t he tumor is located inhale and exhale by creating a virtual tumor in the self-produced moving phantom, and to check the distribution of dose in the treatment plan and the accuracy of tumor in PTV for respiratory and lung cancer patients. It was confirmed that 97% or more respiratory control radiation therapy was effective even if the moving area was more than 3cm, in the 40% to 70% range. Dose distribution with respiratory radiation therapy applied to moving targets, measured by film in the actuation phantom, was shown to be within a 3mm margin of error for dose distribution containing 90%. It was confirmed that for actual patient breathing curves, the treatment time may be shorter than that due to the longer expiratory time.

Adjacent Matrix-based Hole Coverage Discovery Technique for Sensor Networks

  • Wu, Mary
    • Journal of the Korea Society of Computer and Information
    • /
    • v.24 no.4
    • /
    • pp.169-176
    • /
    • 2019
  • Wireless sensor networks are used to monitor and control areas in a variety of military and civilian areas such as battlefield surveillance, intrusion detection, disaster recovery, biological detection, and environmental monitoring. Since the sensor nodes are randomly placed in the area of interest, separation of the sensor network area may occur due to environmental obstacles or a sensor may not exist in some areas. Also, in the situation where the sensor node is placed in a non-relocatable place, some node may exhaust energy or physical hole of the sensor node may cause coverage hole. Coverage holes can affect the performance of the entire sensor network, such as reducing data reliability, changing network topologies, disconnecting data links, and degrading transmission load. It is possible to solve the problem that occurs in the coverage hole by finding a coverage hole in the sensor network and further arranging a new sensor node in the detected coverage hole. The existing coverage hole detection technique is based on the location of the sensor node, but it is inefficient to mount the GPS on the sensor node having limited resources, and performing other location information processing causes a lot of message transmission overhead. In this paper, we propose an Adjacent Matrix-based Hole Coverage Discovery(AMHCD) scheme based on connectivity of neighboring nodes. The method searches for whether the connectivity of the neighboring nodes constitutes a closed shape based on the adjacent matrix, and determines whether the node is an internal node or a boundary node. Therefore, the message overhead for the location information strokes does not occur and can be applied irrespective of the position information error.

An Experimental Study on the Noise Reduction of Cooling Fans for Four-ton Forklift Machines (4톤급 지게차 냉각홴 소음 저감에 관한 실험적 연구)

  • Choi, Daesik;Kim, Seokwoo;Yeom, Taeyoung;Lee, Seungbae
    • Journal of Drive and Control
    • /
    • v.18 no.1
    • /
    • pp.1-8
    • /
    • 2021
  • This paper presents research on methods for the reduction of forklifts' noise level for the increased comfort and safety of its operator. A cooling fan with a high air volume flow rate installed in the forklift acts as an important design parameter which efficiently cools the heat exchanger system, helping to transfer internal heat from the engine room to the outdoors with both transmitted and diffracted opening noises. The cooling fan contributes significantly to both the forklift's emitted sound power and the operator room's noise level, thereby necessitating research on the forklift's reduction of acoustic power level and transmission. A noise analysis for various fan models with a biomimetic design based on eagle-wing geometry was conducted. In addition to the acoustic power generation, the aerodynamic performance of the cooling blade is also strongly influenced by the design of airfoil distribution, thereby requiring optimization. The cooling fans were fabricated and installed in the forklift in order to check the efficacy of the forklift engine's cooling, and the final version of the fan was measured for its ability to lower acoustic power level and cool the engine room. This study explains the aerodynamic and acoustic features of the designed fans with the use of BEM analysis and forklift test results.

Clinical Research Using Salviae Miltiorrhizae Radix-Pharmacopuncture for Lumbar Herniated Intervertebral Disc: Analysis of Trends

  • Kim, Seon Woo;Park, Cheol Woo;Jo, Myeong Jae;Kim, Min Wook;Yu, Jae Hee;Hee, Jeon Seok;Jang, Seung Won;Kang, Do Young;Jeong, Hyun Jin
    • Journal of Acupuncture Research
    • /
    • v.38 no.1
    • /
    • pp.1-7
    • /
    • 2021
  • This review of national and international randomized controlled trials of Salviae miltiorrhizae radix pharmacopuncture for lumbar herniated intervertebral discs was performed to assess its clinical efficacy. There were 5 online databases (PubMed, EMBASE, CNKI, NDSL, OASIS, and RISS) searched on June 1st, 2020. Studies were selected according to the inclusion and exclusion criteria and were reviewed by risk of bias assessment. This review included 14 Chinese studies. The sample sizes ranged from 50 to 100. The numbers of treatments ranged from 20 to 30, with most patients receiving 20 treatments. The longest treatment periods were 10-15 and 15-20 days, of which each accounted for 29% of the studies. The most frequently used evaluation indices were the Japanese Orthopedic Association and the Visual Analog Scale scoring method. The most frequently used acupoints were EX18 and BL25, which accounted for 31% of the total number of acupoints. In 50% of the studies, the pharmacopuncture injection volume was 2 mL. Acupuncture treatment was the most common control group. Eleven studies reported that the intervention group had significantly improved symptoms. However, most of the included studies were of low quality.

Cr Electroplating Technology to prevent Interdiffusion between Metallic Fuel and Clad Material (금속연료-피복재 상호확산 방지를 위한 크롬 도금법 적용 연구)

  • Kim, Jun Hwan;Lee, Kang Soo;Yang, Seong Woo;Lee, Byoung Oon;Lee, Chan Bock
    • Korean Journal of Metals and Materials
    • /
    • v.49 no.12
    • /
    • pp.937-944
    • /
    • 2011
  • Studies have been carried out in order to reduce fuel-cladding chemical interaction (FCCI) behavior of metallic fuel in sodium-cooled fast reactors (SFR) using an electroplating technique. A $20{\mu}m$ thick Cr layer has been plated by the electrochemical method in the Sargent bath over the HT9 (12Cr-1Mo) clad material and diffusion couple tests of the U-10Zr metallic fuel as well as the rare earth alloy (70Ce-29La) have been conducted. The results show that the Cr plating can prevent FCCI behavior along the fuel-clad interface. However, cracks developed through the thickness during plating, which resulted in the migration of some fuel constituents. Variation of bath temperature, application of pulse current, and post heat treatment have been conducted to control such cracks. We found out that some conditions like the pulse current and the post heat treatment enhanced the layer property by reducing the internal cracks and improving the diffusion couple test.

Financial Performance of M&A: Focusing on E-commerce Companies in China (M&A 기업성과: 중국 전자상거래 기업을 중심으로)

  • Zhang, Cong;Jin, Shanyue
    • Journal of Digital Convergence
    • /
    • v.20 no.4
    • /
    • pp.119-126
    • /
    • 2022
  • With the rise and rapid development of the "Internet+" economic model, the internet is deeply integrated with the social economy and penetrates every corner of life. Compared with expanding the scale of business operations through internal investment and capital accumulation, e-commerce companies are more inclined to directly gain control of other companies through efficient merger and acquisition (M&A). The purpose of this study is to analyze changes in financial performance before and after M&A of Alibaba, China's largest e-commerce company in the Internet era. To present the impact of M&A events on Alibaba's stock price and shareholder wealth more intuitively, this study selected the market model in the event study method to measure abnormal returns. The results show that an M&A event led to a reduction in Alibaba's shareholder wealth in the short term. This study presents the theoretical basis for the M&A performance of e-commerce companies.