• 제목/요약/키워드: MHP

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신체 외부 통신에서 MHP 펄스와 터너리 코드를 이용한 다중접속 기법 (Multiple Access Scheme Using Modified Hermite Polynomial Pulse and Ternary code for Out-Body WBAN)

  • 심재준;황재호;김재명
    • 인터넷정보학회논문지
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    • 제12권1호
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    • pp.27-38
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    • 2011
  • 본 논문에서는 신체 외부 고속 통신을 위한 UWB-IR(Ultra Wide Band-Impulse Radio)을 알아보고 다중 접속 시 발생하는 간섭을 완화하고 전송 효율을 높이기 위해 MHP(Modified Hermite Polynomial)펄스와 터너리 코드를 이용한 다중접속 기법을 제안한다. 상호 직교성을 가지는 MHP 펄스와 터너리 코드를 이용하여 신호를 전송할 경우, 신체 외부 고속 및 저속 통신에서 다중접속 시 발생하는 다중 사용자 간섭을 완화하고 다중 사용자간의 신호 구분이 가능하다. 신호 심볼구조에서 MHP 펄스와 터너리 코드 그리고 시간도약 구간을 설정하여 동기식과 비동기식 고속전송 그리고 동기식과 비동기식 저속전송의 경우에서 최적의 전송기법을 찾고 검증한다. 시뮬레이션을 통해 동기식 구조에서 MHP 펄스를 이용하여 전송한 경우 가우시안 펄스를 사용한 경우보다 2~3dB 향상됨을 확인하였다. 또한 비동기식 구조에서의 신호충돌을 회피하기 위해 터너리 코드를 사용하여 전송하여 향상된 다중접속 기법을 확인하였다.

타이밍 지터 환경에서 MHP 펄스를 이용한 M 진 초광대역 시스템의 성능분석 (Performance Analysis of M-ary UWB System using MHP Pulses in the Presence of Timing Jitter)

  • 황준혁
    • 한국정보통신학회논문지
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    • 제19권1호
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    • pp.69-76
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    • 2015
  • 본 논문은 MHP 펄스의 직교성을 이용한 M진 초광대역(UWB) 시스템을 제안하고 시스템의 성능을 분석한다. 제안하는 M진 초광대역 시스템은 각 펄스 차수 간에 직교하는 특성을 가지는 MHP 펄스를 선형 결합하여 펄스진폭방식으로 데이터를 M진으로 전송한다. 제안하는 M진 초광대역 시스템의 성능을 분석하기 위해 MHP 펄스의 상관함수를 구하고, AWGN 환경과 타이밍 지터 환경에서 시스템의 성능을 분석한다. 제안하는 M진 초광대역 시스템은 기존의 M진 초광대역 시스템에 비해서 비트오류확률(BER)이 향상되며, 타이밍 지터에 강인하고 방사전력이 낮다는 특성을 가짐을 보인다. 제안하는 M진 초광대역 시스템에 에러코딩 기법이나 레이크 수신기를 결합하여 사용하면 시스템의 성능은 더욱 더 향상될 것이다.

Modified Hermite Polynomial 펄스들을 사용하는 M진 다중접속 UWB 시스템의 성능 분석 (Performance Analysis of M-ary Multiple Access UWB System Using Modified Hermite Polynomial Pulses)

  • 황준혁;김석찬;박동찬;김병철
    • 한국통신학회논문지
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    • 제33권9A호
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    • pp.909-916
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    • 2008
  • 이 논문은 초광대역(Ultra WideBand: UWB) 임펄스 라디오(Impulse Radio: IR) 시스템에서 Modified Hermite Polynomial(MHP) 펄스들을 이용한 M진 펄스차수 시간도약 다중접속(Pulse Order-Time Hopping-Multiple Access: PO-THMA) 방법을 제안하고, 시스템의 비트오류율(Bit Error Rate: BER)을 분석한다. 제안하는 다중접속 방법은 상호간에 직교성을 가지는 MHP 펄스들을 사용하여 동일한 칩 시간에 펄스들이 존재하더라도 섞임 없이 구분해 낼 수 있는 성질을 이용하여 다중 접속용량 증가시킬 수 있다. 제안하는 시스템의 성능 분석을 위해 데이터 전송에 사용한 MHP 펄스들의 상호 상관함수를 구하고, 기존이 다중접속 방식과 비교하여 데이터 전송율과 BER 성능이 개선됨을 보인다.

근전의수의 내구성 시험방법에 대한 연구 (Study on a test method for the endurance of myoelectric hand prosthesis)

  • 최기원;문무성
    • 재활복지공학회논문지
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    • 제5권1호
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    • pp.11-15
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    • 2011
  • 본 논문은 사함의 근육에서 발생하는 근전위 신호에 의해서 제어되는 근전의수의 성능에 대한 시험방법을 제안한 것이다. 근전의수는 기계적인 의수, 근전위 신호를 측정하는 표면 근전위 센서, 제어시스템, 그리고 충전용 배터리로 구성되어 있다. 상용화 된 근전의수를 가지고 파지 내구성을 시험한 결과 소음과 파지력은 큰 차이가 없었다. 제안된 시험방법은 내구성 시험을 통하여 근전의수의 신뢰성을 검증하였다.

편조형 윅을 갖는 소형 히트파이프의 냉각특성에 관한 연구 (A Study on Cooling Characteristics of Miniature Heat Pipes with Woven-Wired Wick)

  • 문석환;김광수;최춘기
    • 설비공학논문집
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    • 제12권3호
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    • pp.227-234
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    • 2000
  • An experimental study was performed for understanding the limiting power and heat transfer characteristics of an MHP having the diameter of 3 or 4 mm which could be applied to cooling of miniature electronic equipment such as the notebook PC CPU etc. The experimental parameters which are inclination, structure of the wick, the length of the condenser and the total heat pipe were considered. The MHP with a woven-wired wick has the advantages of the improvement in capillary limit, the effective attachment tightly toward wall and the convenience in construction of wick. Cooling performance of the present MHP was compared with that of MHP with grooved, fine fiber and sintered type wick which were applied by existing enterprises. With respect to the inclination of$ -5^{\circ}$ , an MHP having the diameter of 3 or 4 mm shows the limiting power of 6~14 W. Therefore, it is expected that the MHP of the present study has sufficient applicability of cooling of notebook PC of which the amount of heat generated is about 12 W.

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Manual Handling in Aged Care: Impact of Environment-related Interventions on Mobility

  • Coman, Robyn L.;Caponecchia, Carlo;McIntosh, Andrew S.
    • Safety and Health at Work
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    • 제9권4호
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    • pp.372-380
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    • 2018
  • The manual handling of people (MHP) is known to be associated with high incidence of musculoskeletal disorders for aged care staff. Environment-related MHP interventions, such as appropriate seated heights to aid sit-to-stand transfers, can reduce staff injury while improving the patient's mobility. Promoting patient mobility within the manual handling interaction is an endorsed MHP risk control intervention strategy. This article provides a narrative review of the types of MHP environmental controls that can improve mobility, as well as the extent to which these environmental controls are considered in MHP risk management and assessment tools. Although a range of possible environmental interventions exist, current tools only consider these in a limited manner. Development of an assessment tool that more comprehensively covers environmental strategies in MHP risk management could help reduce staff injury and improve resident mobility through auditing existing practices and guiding the design of new and refurbished aged care facilities.

금속 할라이드 페로브스카이트 나노와이어의 광 센서 소자 응용 (Alignment of Metal Halide Perovskite Nanowires and Their Application in Photodetectors)

  • 신문렬;최지훈
    • 한국재료학회지
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    • 제32권6호
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    • pp.307-312
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    • 2022
  • Metal halide perovskite (MHP) nanocrystals (NCs) have emerged as promising materials for various optoelectronic applications including photovoltaics, light-emitting devices, and photodetectors because of their high absorption coefficient, high diffusion length, and photoluminescence quantum yield. However, understanding the morphological evolution of the MHP NCs as well as their controlled assembly into optoelectronic devices is still challenging and will require further investigation of the colloidal chemistry. In this study, we found that the amount of n-octylamine (the capping agent) plays a crucial role in inducing further growth of the MHP NCs into one-dimensional nanowires during the aging process. In addition, we demonstrate that the dielectrophoresis process can permit self-alignment of the MHP nanowires with uniform distribution and orientation on interdigitated electrodes. A strong light-matter interaction in the MHP NWs array was observed under UV illumination, indicating the photo-induced activation of their luminescence and electrical current in the self-aligned MHP nanowire arrays.

Efficacy of bivalent vaccines of porcine circovirus type 2 and Mycoplasma hyopneumoniae in specific pathogen-free pigs challenged with porcine circovirus type 2d

  • Lim, Jeonggyo;Jin, Myongha;Yoon, Injoong;Yoo, Han Sang
    • Journal of Veterinary Science
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    • 제23권3호
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    • pp.49.1-49.13
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    • 2022
  • Background: Porcine circovirus type 2 (PCV2) and Mycoplasma hyopneumoniae (MHP) are economically significant pathogens in the pig industry. The use of combined vaccines against PCV2 and MHP is one of the most effective ways of protecting pigs from both diseases, and it has become a part of general management. Objectives: This study evaluated the efficacy of two new bivalent vaccines of PCV2 and MHP (Myco-X and Myco-XD) in SPF pigs. Myco-X and Myco-XD are a combined vaccine of MHP with PCV2b and PCV2d, respectively. Methods: Sixteen pigs were divided into four groups: Myco-X-vaccinated challenged, Myco-XD-vaccinated challenged, unvaccinated challenged, and unvaccinated unchallenged. Two milliliters of Myco-X were administered intramuscularly, and 0.5 mL of Myco-XD was injected intradermally at 3 wk of age. The pigs were challenged with virulent PCV2d via the intramuscular and intranasal route 4 wk post-vaccination. Results: All vaccinated pigs showed effective reduction of the clinical signs, the PCV2d load in the blood and nasal swab samples, as well as lung and lymphoid tissue lesions in the challenge test. Compared to unvaccinated challenged animals, the vaccinated challenged animals showed significantly higher (p < 0.05) levels of anti-PCV2 IgG, PCV2d-specific interferon-γ (IFN-γ), and anti-MHP IgG. Conclusions: Based on clinical, microbiological, serological, and pathological assessments, this study confirmed that both combined vaccines could protect pigs against PCV2 infection caused by PCV2d. On the other hand, further research on the efficacy evaluation of these new vaccines against the MHP challenge and PCV2d/MHP co-challenge is needed.

Effect of a new phosphorus source, magnesium hydrogen phosphate (MHP) on growth, utilization of phosphorus, and physiological responses in carp Cyprinus carpio

  • Yoon, Tae-Hyun;Won, Seunggun;Lee, Dong-Hoon;Choi, Jung-Woo;Ra, Changsix;Kim, Jeong-Dae
    • Fisheries and Aquatic Sciences
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    • 제19권9호
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    • pp.39.1-39.9
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    • 2016
  • Magnesium hydrogen phosphate (MHP, $MgHPO_4$) recovered from swine manure was prepared as an alternative phosphorus (P) source. Conventional P additives, monocalcium phosphate (MCP), dicalcium phosphate (DCP), and tricalcium phosphate (TCP) were compared with the MHP in terms of growth and P availability by juvenile carp Cyprinus carpio. A basal diet as a negative control was prepared using practical feed ingredients without P supplementation to which four supplemental P sources were added at the level of 2%. Five groups of 450 fish having mean body weight of 6.5 g following 24 h fasting after 2 weeks of adaptation period were randomly distributed into each of 15 tanks (30 fish/tank). Fish were hand-fed to apparent satiety twice a day for 9 weeks. Fish fed the MHP had weight gain (WG), feed conversion ratio (FCR), protein efficiency ratio (PER), and specific growth rate (SGR) comparable to those fed the MCP. Those values of both the MHP and MCP groups were significantly different (p < 0.05) from the other groups. Fish groups fed control and the TCP showed the lowest WG, PER, and SGR and the highest FCR among treatments. No fish were died among treatments during the experimental period. Fish fed control and the TCP showed hematocrit and hemoglobin significantly lower (p < 0.05) than fish fed the MHP. The lowest inorganic P (Pi) in plasma was found in the control group. Even though Pi was not significantly different (p > 0.05) from other phosphate groups, fish fed the MCP and MHP retained higher P in whole body than the other groups. P availability was determined to be 93.2, 62.4, 6.1, and 98.0% for MCP, DCP, TCP, and MHP, respectively. The present results suggested that the MHP recovered from wastewater stream could be used as an alternative P source in carp diet.

섬유금속적층판 제작을 위한 PTFE 몰드 기반 마이크로파 공정에 대한 실험적 연구 (Experimental Study on Manufacturing Fiber Metal Laminate using Microwave Heating Based on PTFE Mold)

  • 박으뜸;이영헌;김정;강범수;송우진
    • 소성∙가공
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    • 제29권4호
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    • pp.179-187
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    • 2020
  • Existing composite forming processes such as the autoclave, prepreg compression forming (PCF), RTM, etc. require high production costs because of their long processing time. On the other hand, microwave heating process (MHP) can reduce the production costs since both mold and composite material can be heated directly. The aim of this study is to manufacture a mold consisting of polytetrafluoroethylene (PTFE), quartz glass, stainless steel clamps, and polyether ether ketone (PEEK) bolts for fabricating FML based on self-reinforced polypropylene (SRPP) using the MHP. First, the flame test was carried out prior to the MHP to check the temperature on the mold and whether the spark occurred at the mold and the edge of the FML. Second, the uniaxial tensile test was then conducted to obtain the mechanical properties of the FML manufactured by the MHP. The mechanical properties were compared with those of the FML fabricated by the PCF. As a result, the MHP using the PTFE mold can manufacture the FML more rapidly than the PCF, and obtain acceptable mechanical properties.