• Title/Summary/Keyword: aPTT

검색결과 248건 처리시간 0.025초

광전용적맥파 센서를 이용한 맥파전달시간의 측정 (Measurement of Cardiac Pulse Transit Time using Photoplethysmography Sensor)

  • 최병철;정동근;정도운;노정훈;전계록
    • 센서학회지
    • /
    • 제13권5호
    • /
    • pp.383-391
    • /
    • 2004
  • In this study, we implemented the pulse transit time (PTT) system to examine usefulness of the monitoring method of distensibility and elasticity using photoplethysmography sensor in vivo. PTT is defined as the time interval between the peak of QRS complex in ECG signal and the maximum slope point of photoplethysmography. these two signals were converted to digital data by means of AID converter, then PTT was evaluated by heartbeat using PC. Results of analysis were displayed as a graph using spline interpolation method. The variance of PTT was measured repetitiously to verify efficiency of PTT system in resting state and hyperemic state. Repeated measurement of PTT was not same value but showed that coefficients of correlation were related with each other as 0.8302 (P<0.01) in resting state. And also repeated measurement of PTT showed significant correlation as 0.868 (P<0.01) in the hyperemic state. These result showed that PTT is reflect on transient pressure variance in the artery and is very useful method for the evaluation of prognosis of the hypertension and arteriosclerosis.

PTT[Poly(trimethylene terephthalate)] 직물(織物)의 물리적(物理的) 특성(特性)및 주관적(主觀的) 평가(評價)에 관(關)한 연구(硏究) (A Study on the Physical Properties and Subjective Evaluation of the PTT[Poly(trimethylene terephthalate)] Fabric)

  • 서효정;김종준;전동원
    • 패션비즈니스
    • /
    • 제7권4호
    • /
    • pp.121-128
    • /
    • 2003
  • A new textile material, poly(trimethylene terephthalate) polymer, has been introduced to the textile industry. The structure of PTT is similar to the PET, while the tensile deformation and subsequent recovery property is better than that of PET. In this study, the physical and mechanical properties of textile woven fabrics made of PTT, PET, and nylon 6 yarns as the filling yarn were determined using the Kawabata Evaluation System (KES), including tensile, bending, shearing, compression, and surface related parameters. On top of these measurements, the subjective ratings by evaluators were performed on the fabric samples. From the examination of the stress-strain behavior of the yarn specimens focused on the recovery mode, it was evident that the PTT specimen developed lower stress at 3% elongation. The subsequent recovery curve showed that the PTT has less stress-decay rate than the other specimens, implying that the recovery behavior of the PTT is recommendable for the end-uses including stretchable textile materials, sports wears, etc. The KES bending rigidity(B) value of the PTT sample fabric was lower than that of the PET sample fabric. Subjective evaluation of the fabric samples by the evaluators on the descriptive word pair "soft - not soft" showed similar tendency with the KES B determination of the fabric samples.

Phase Transformation of Poly(trimethylene terephthalate) in Crystalline State: An Atomistic Modeling Approach

  • Jang, Seung-Soon;Jo, Won-Ho
    • Fibers and Polymers
    • /
    • 제1권1호
    • /
    • pp.18-24
    • /
    • 2000
  • The phase transformation of poly(trimethylene terephthalate) in crystalline state was simulated by atomistic modeling using molecular mechanics technique. The crystalline structure of PTT was successfully prepared using the well-defined unit cell structure of PTT and was satisfactorily verified by comparing that with the structure obtained from the x-ray diffraction experiments. The basic elastic properties were predicted in this study, showing that the crystalline structure of PTT is very pliable to the deformation at small strain. When the crystalline structure of PTT was stepwise deformed up to 50% of strain in chain direction under uniaxial extension condition, the change in dihedral angle of trimethylene unit from gg to tt conformation was accompanied with a large increase of stress, indicating that the phase transformation of PTT in crystalline state is difficult to occur.

  • PDF

Polytrimethylene terephthalate(PTT) 가연사의 수축거동에 관한 연구 (A Study on Shrinkage Properties of Polytrimethylene Terephthalate (PTT) Drawn Textured Yarn)

  • 최재우;장봉식
    • 한국의류산업학회지
    • /
    • 제6권4호
    • /
    • pp.492-496
    • /
    • 2004
  • Shrinkage properties of drawn textured Poly(trimethylene terephthalate, PTT) yarn, which has been developed recently, were investigated to provide fundamental information for the textile industry. Shrinkage ratio characteristics on PTT yarn with six different count were investigated with tension, dry and wet thermal temperature. In non-tension, the shrinkage ratio were increased to increasing temperature at dry and wet thermal treatment, and in tension, the shrinkage ratio were increased to increasing tension at dry and wet thermal treatment.

UV/Ozone 조사에 의한 PTT 필름의 연속식 표면처리와 염색성 (Continuous Surface Treatment and Dyeability of PTT Film via $UV/O_3$ Irradiation)

  • 장진호;박대선
    • 한국염색가공학회지
    • /
    • 제17권1호
    • /
    • pp.7-13
    • /
    • 2005
  • Continuous and intense UV irradiation on PTT film using two types of UV bulbs at different irradiation power level was carried out to modify surface characteristics of the film including zeta potential, wettability, surface energy, and dyeability. ESCA analysis of the irradiated film showed higher O/C ratio than the untreated film indicating photooxidation of outer surface layer. ATR analysis showed that the ester bonds were broken and some new groups were produced such as carboxylic acid, phenolic hydroxy, and other esters, implying that ester bonds of PTT was responsible for the observed photooxidation effect. The surface of the treated PTT film became more hydrophilic and wettable to water, coupled with increased surface energy. Polar component of the surface energy increased and nonpolar component decreased with increasing irradiation energy. The treatment also decreased zeta potential of the modified surface and nanoscale roughness increased with increasing irradiation. The dyeability of the treated films to catonic dyes was significantly improved by electrostatic and polar interaction between dye molecules and the anionic film surface. The UV irradiation seems to be a viable polymer surface modification technology, which has advantages such as no vacuum requirement and continuous process unlike plasma treatment.

Energy Level이 다른 분산염료를 이용한 Poly(trimethylene terephthalate)섬유의 염색성 (The Dyeing Properties of Poly(trimethylene terephthalate) by Disperse Dyes with Different Energy Level)

  • 백지연;김정렬;이난형;윤태희;김삼수
    • 한국염색가공학회지
    • /
    • 제15권5호
    • /
    • pp.316-320
    • /
    • 2003
  • In order to investigate the dyeing property of poly trimethylene terephthalate(PTT) fabric, the dyeing of PTT fabric was carried at under condition of different dyeing temperature by using several disperse dyes with different energy level. Particularly, this study discussed the PTT dyeing thermodynamically. Used disperse dyes were selected based on the their chemical structure and energy level. The obtained results were as followings; The dye adsorption of S type disperse dye such as C. I. Disperse Blue 79 increased with increasing dyeing temperature. In a exhaustion rate of PTT fabric with disperse dyes, C. I. Disperse Blue 56 showed higher values than that of C. I. Disperse Orange 29 and Blue 79. For the interpretation of thermodynamic dyeing behavior, the partition coefficient ( K ) and some several thermodynamic parameters such as standard affinity$(-\mu^\circ)$ and heat of dyeing$(\Delta{H}^\circ)$ calculated from the adsorption isotherm. From above results, as the energy level of disperse dye is small, the partition coefficient and standard affinity increased. But the heat of dyeing of PTT fabric with disperse dye showed high negative value in order of E type(C. I. Disperse Blue 56), SE type(C. I. Disperse Orange 29) and S type(C. I. Disperse 79).

열처리 온도가 Poly(trimethylene terephthalate)(PTT) 섬유의 역학적 성질과 미세구조에 미치는 효과 (The Effects of Annealing Temperature on The Physical Properties and Fine Structure of Poly(trimethylene terephthalate)(PTT) Fibers)

  • 정경희;이언필;이재호
    • 한국의류산업학회지
    • /
    • 제15권6호
    • /
    • pp.985-992
    • /
    • 2013
  • Polytrimethylene terephthalate(PTT) offers several advantageous properties such as good tensile strength, uniformity, stiffness, toughness, UV stability, resilience, stain resistance, outstanding elastic recovery, and dyeability. The effects of annealing temperature on physical properties and the structure of PTT filaments and yarn were investigated by measuring wide-angle X-ray diffraction (WAXD), density, optical birefringence, dynamic visco elasticity, and tensile testing. The intensity of maximum tan ${\delta}$ decreased and the temperature of maximum tan ${\delta}$ shifted to a higher temperature as the annealing temperature of filaments increased; however, it shifted to a lower temperature when the annealing temperature exceeded $130^{\circ}C$. In addition, crystallinity, density and D-spacing of (010) crystal face increased as the annealing temperature increased. Optical birefringence and specific stress were almost constant up to $100^{\circ}C$ and then decreased above $130^{\circ}C$. The shrinkage of PTT filament is 0 in boiling water when annealed above $130^{\circ}C$; consequently, the use of annealed fiber above $130^{\circ}C$ can remove thermal instability when dyeing PTT fiber. In the case of yarns, the thermal stability and physical properties of yarns showed the best effect when the ply number is less than 5, twist number is less than 400tpm, and the annealing time is 20minutes.

곤충병원세균(Photorhabdus temperata ssp. temperata) 유래 곤충 면역 억제물질 생성 비교 연구를 통한 저렴한 세균 배지 선발 (Comparative Analysis of Immunosuppressive Metabolites Synthesized by an Entomopathogenic Bacterium, Photorhabdus temperata ssp. temperata, to Select Economic Bacterial Culture Media)

  • 서삼열;장호진;김건우;김용균
    • 한국응용곤충학회지
    • /
    • 제49권4호
    • /
    • pp.409-416
    • /
    • 2010
  • 곤충병원세균인 Photorhabdus temperata ssp. temperata(Ptt)는 곤충의 면역반응을 억제시켜 피기생 곤충 체내에서 공생하는 기주 선충의 발육을 도모하게 된다. 또한 Ptt의 변역억제 활성은 Bacillus thuringiensis(Bt)의 병원성을 증가시킨다. 본 연구는 이러한 유용 곤충병원세균의 대량 생산을 위한 저렴한 배지를 선발하기 위해 수행되었으며, 두 연구용 배지(LB, TSB)와 저렴한 산업용 두 배지(MY, M2)를 상호 비교하였다 모든 배양액에 동일한 밀도의 Ptt를 접종하고 배양하였을 때 48 시간 이후 정지상이 나타났다. 그러나 연구용 배양액인 LB와 TSB에서 두 가지 산업용 배양액보다 정지상에서 높은 세균 밀도를 보였다. 네 가지 배지에서 증식된 Ptt 배양액은 모두 배추좀나방(Plutella xylostella) 3령충에 대한 Bt 병원성을 현격하게 제고시켰고, 이들 배지 종류에 따라 치아가 없었다. 네 가지 배양액에서 세균의 증식에 의해 생산되는 대시물질의 양과 배지별 생산되는 대사물질의 동일성을 확인하기 위해 헥산과 에틸아세테이트의 유기용매로 추출했다. 시간별 배양액의 유기용매 추출물질은 세균의 증식과 비슷하게 대사물질의 생산량에서도 증가하는 것을 알 수 있었다. 역상 HPLC를 이용하여 네 가지 세균 배양액 각각에서 대사물질을 분리하였고, 정량적으로 네 가지 대사물질이 서로 다른 배지에서 통계적으로 차이 없이 검출되었다. 본 연구는 비교적 저렴한 두 가지 산업용 배지가 유용 대사물질의 생성에 변화 없이 Ptt 세균을 저렴하게 배양할 수 있다고 제시하고 있다.

일상생활 건강 모니터링을 위한 착용형 PTT 측정 시스템의 구현 (Implementation of the wearable PTT measurement system for health monitoring during daily life)

  • 예수영;노윤홍;정도운
    • 한국정보통신학회논문지
    • /
    • 제15권1호
    • /
    • pp.220-226
    • /
    • 2011
  • 맥파전달시간 측정을 위해 비침습적 방법으로 신체 착용 가능한 심전도 및 맥파 무선계측시스템을 구현하였다. 구현된 시스템을 이용하여 자세 변화에 따른 맥파전달시간의 변화를 관찰하고자 하였다. 맥파전달시간을 검출하기 위하여 심전도 및 맥파 신호 검출이 필요하고, 맥파신호 계측을 위하여 근적외선을 피검부위에 조사하여 헤모글로빈에 흡수되지 않고 투과된 투과광 또는 반사광으로 혈액량의 변동을 보는 광적용적맥파를 이용하였다. 또한 검출된 심전도와 맥파 신호를 무선으로 PC로 전송하기 위하여 Zigbee호환의 무선센서노드를 이용하였으며, 무선으로 전송된 데이터로부터 잡음을 제거하고 맥파전달시간을 계산하기 위한 신호처리 알고리즘을 구현하였다. 구현된 맥파전달시간 계측시스템의 유용성을 평가하기 위하여 기존 상용시스템과의 비교 평가를 수행하였으며, 자세 변화에 따른 맥파전달시간의 변화양상을 관찰하여 구현된 시스템을 통해 일상생활에서 건강모니터링이 가능함을 확인하였다.

Transesterification and Compatibilization in the Blends of Bisphenol-A Polycarbonate and Poly(trimethylene terephthalate)

  • Na Sang-Kuwon;Kong Byeong-Gi;Choi Changyong;Jang Mi-Kyeong;Nah Jae-Woon;Kim Jung-Gyu;Jo Byung-Wook
    • Macromolecular Research
    • /
    • 제13권2호
    • /
    • pp.88-95
    • /
    • 2005
  • Melt blending of Bisphenol A polycarbonate (PC) and poly(trimethylene terephthalate) (PTT) was carried out over the entire composition range. The mixing time was varied up to 90 min. The resulting samples were analyzed by FT-IR, DSC, XRD, DMTA, $^{1}H NMR$, and SEM. The process of transesterification between the two polymers and their resulting compatibilization were observed. The behaviors of the PTT-rich and PC-rich blends were different and an equilibrium was found to exist. Peculiar behavior, which was different from that of the PTT-rich and PC-rich blends, was exhibited by the 50/50 (PTT/PC) blend.