• 제목/요약/키워드: Normal Pressure

검색결과 2,330건 처리시간 0.029초

Mycelial growth of Lentinula edodes in response to different mixing time, pressure intensity, and substrate porosity

  • Chang, Hyun You;Seo, Geum Hui;Lee, Yong Kuk;Jeon, Sung Woo
    • 한국버섯학회지
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    • 제15권4호
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    • pp.164-167
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    • 2017
  • Biological efficiency (BE), the ratio of fresh mushrooms harvested per dry substrate weight, expressed as the percentage of Lentinula edodes, also known as shiitake, was determined using the 'Sanjo 701' strain stored in the Department of Mushroom at the Korea National College of Agriculture and Fisheries. The mycelia were grown in glass columns with varying levels of moisture content and varying mixing periods of 0.5, 1, 2, and 3 hours. The substrate was sterilized using a steam pressure autoclave sterilizer at normal and high pressure to avoid contamination. The results showed that mycelial growth (126 mm/15 days) was optimized at 55% moisture content. The best mycelial growth of 117 mm/15 days was obtained with 2 hours of mixing time. Normal pressure sterilization yielded better results with mycelial growth of 96 mm/15 days at $100^{\circ}C$ compared to 88 mm /15 days with sterilization at $121^{\circ}C$. Mycelial density was higher, i.e. 3(+++), with normal pressure sterilization compared to 2(++) with high pressure sterilization. Furthermore, sawdust mixed with 5% woodchips increased the substrate porosity and yielded higher mycelial growth. Thus, we demonstrated that the optimum harvest or potential increased yield of shiitake can be obtained by modulating moisture content, mixing time, and substrate porosity.

도플러 초음파를 이용한 인공판막 상하의 압력차 측정에 관한 연구 -승모판막 치환에 사용한 Duromedics 인공판막과 정사인의 승모판막과의 비교연구- (Noninvasive assessment of pressure gradients across prosthetic heart valve by doppler ultrasound -A comparative studyof the duromedics bileaflet valves in mitral position and normal mitral valves-)

  • 진성훈;서경필
    • Journal of Chest Surgery
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    • 제20권2호
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    • pp.223-229
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    • 1987
  • Doppler echocardiography provides valuable information regarding prosthetic heart valve function rather than structure. There are three methods of expressing the severity of mitral valve obstruction: the transvalvular pressure gradient, effective valve area, and pressure half-time. Of these, the transvalvular pressure gradient [~p] can be determined by the measurement of maximum transvalvular blood flow velocity [V] according to the modified Bernoulli`s equation [gp=4V*]. Eleven patients, who underwent mitral valve replacement with Duromedics mechanical prostheses, and 17 normal persons were investigated. There were significantly higher calculated pressure gradients in prosthetic than normal mitral valves [9.*10*2.22mmHg-vs-3.26*0.99mmHg:p<0,01], and there was a inverse relationship between pressure gradient and prosthetic valve size [11.17*0.%mmHg in size 27mm and 29mm -v- 7.38*1.12mmHg in size 31mm and 33mm; r=0.85, p<0.01] The noninvasive Doppler technique should be useful in the diagnosis of prosthetic valve obstruction.

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감염병전문병원의 시설 가이드라인에 관한 연구 - 운영방식과 건축계획을 중심으로 (A Study on the Establishment of Facility Guidelines for Infectious Diseases Hospitals - Focusing on Operational Methods and Architectural Planning)

  • 최광석
    • 의료ㆍ복지 건축 : 한국의료복지건축학회 논문집
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    • 제28권2호
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    • pp.17-29
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    • 2022
  • Purpose: In terms of efficiency and safety, this study attempted to organize data on the operation methods and architectural planning of infectious diseases hospitals. Methods: The results obtained through on-site and interview surveys with hospital officials and medical staffs at four infectious diseases hospitals under construction were summarized based on those original business plans and facility guidelines. Results: First, the operational methods to secure safety and operational efficiency were summarized for each department which are major hospital functions of infectious disease hospitals. Second, as the architectural planning, the characteristics of space and circulation of each department are summarized. For safety of medical staff, negative pressure and non-negative pressure zone have to completely separated. In addition medical staff wears PPE and enters the negative pressure zone and returns in the order of admiral, shower, and gowning in the PPE undressing room after patient treatment. In case of operational efficiency, flexible operation is required in normal and crisis situations. For example, it is important for The Ward to gradually switch to negative pressure beds in times of crisis from normal situation and the outpatient department considers the composition of negative pressure and non-negative pressure outpatient spaces that can operate in parallel even in crisis situations. Implications: Infectious disease hospitals require flexible operation and appropriate facilities for normal and crisis situations.

보행수 측정 및 보행패턴 분류 알고리즘 (A Study on a Algorithm of Gait Analysis and Step Count with Pressure Sensors)

  • 도주표;최대영;김동준;김경호
    • 전기학회논문지
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    • 제66권12호
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    • pp.1810-1814
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    • 2017
  • This paper develops an approach to the algorithm of Gait pattern Analysis and step measurement with Multi-Pressure Sensors. The process of gait consists of 8 steps including stance and swing phase. As 3 parts of foot is supporting most of human weight, multiple pressure sensors are attached on the parts of foot: forefoot, big toe, heel. As 3 parts of foot is supporting most of human weight, multiple pressure sensors are attached on the parts of foot: forefoot, big toe, heel. normal gait proceed from heel, forefoot and big toe over time. While normal gait proceeds, values of heel, forefoot and big toe can be changed over time. So Each values of pressure sensors over time could discriminate whether it is normal or abnormal gait. Measuring Device consists of non-inverting amplifiers and low pass filter. Through timetable of values, normal gait pattern can be analyzed, because of supported weight of foot. Also, the peak value of pressure can judge whether it is walking or running. While people are running, insole of shoes is floating in the air on moment. Using this algorithm, gait analysis and step count can be measured.

수치해석을 활용한 1단 천음속 압축기 내부 유동장 분석 (Numerical Investigation on Internal Flow Field of a Single-Stage Transonic Axial Compressor)

  • 송지한;황오식;박태춘;임병준;양수석;강영석
    • 한국유체기계학회 논문집
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    • 제15권6호
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    • pp.85-91
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    • 2012
  • Numerical simulations on a single stage transonic compressor which is developed by Korea Aerospace Research Institute are carried out and their results are compared with experimental data for cross validations. Comparisons between experimental data and numerical simulation results show good agreements on a performance curve, static pressure and total pressure distributions. CFD results show that there is a clear interaction between tip leakage flow and normal shock in the rotor passage. Tip leakage flows are almost dissipated after the strong normal shock and it forms a strong recirculation near the blade tip. Also a large separation region grows on the suction surface just after the normal shock. As the pressure ratio and blade loading increase, the normal shock line moves upstream and it starts to deviate from the blade leading edge. Then the tip leakage flow does not overcome the strong adverse pressure gradient and flow blockage originated from the tip recirculation region. As a result, the tip leakage flow heads for the neighboring blade leading edge, which results in a compressor stall.

초음속 디퓨져에서 발생하는 수직충격파 진동의 이론해석 (Analysis of Normal Shock-Wave Oscillation in a Supersonic Diffuser)

  • 김희동
    • 한국추진공학회지
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    • 제2권3호
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    • pp.36-46
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    • 1998
  • 초음속 유동에서 발생하는 충격파는 일반적으로 충격파 상류와 하류의 압력비에 의해 일반적으로 결정된다. 본 연구에서는 충격파의 진동현상을 규명하기 위한 연구의 일환으로, 미소교란법(small perturbation method)을 이용하여 이론해석을 수행하였으며, 충격파 하류의 유동장에 에너지 손실을 적용하여 충격파의 안정성을 이론적으로 해석하였다. 이론해석에서는 충격파 상류에 경계층 유동에서 발생하는 난류변동이나 주류에서의 압력변동이 충격파의 진동과 관련된다고 생각하여, 충격파 상류의 유동에 미소압력변동을 적용하여 충격파의 진동특성을 해석하였다. 본 연구의 결과들을 타 연구의 결과와 비교하였으며, 열선풍속계(hot wire)를 이용한 실험적 연구결과와 비교하였다.

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정상 한국성인의 식도내압 측정 (Esophageal Pressure Monitoring in Normal Korean Adults)

  • 정황규
    • Journal of Chest Surgery
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    • 제13권4호
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    • pp.462-469
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    • 1980
  • Here, I and wer report the results of our studying about; 1. The length of esophagus and sphincters; 2. Resting pressure of upper sphincter, upper esophagus, mid-esophagus, lower esophagus and lower sphincter; 3. Pressure changes in swallowing at these points of esophagus; 4. Resting and swallowing pressure curves in these points in 50 normal Korean adults. In addition to these we wbserved pressure inversion point, slow and fast components of phasic pressure which are originating from respiration and heart beat. And we studied transportation time and speed of peristalsis. The speed of peristalsis is faster in the lower esophagus than in the upper. I can probalby be proud in the results of these study because these will become a standard criteria in the further evaluation of esophageal functional disturbances in such lesions as; Achalasia, Hiatal hernia, Esophageal canceer, Scleroderma, diverticula.

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Wind tunnel modeling of roof pressure and turbulence effects on the TTU test building

  • Bienkiewicz, Bogusz;Ham, Hee J.
    • Wind and Structures
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    • 제6권2호
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    • pp.91-106
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    • 2003
  • The paper presents the results of 1:50 geometrical scale laboratory modeling of wind-induced point pressure on the roof of the Texas Tech University (TTU) test building. The nominal (prevalent at the TTU site) wind and two bounding (low and high turbulence) flows were simulated in a boundary-layer wind tunnel at Colorado State University. The results showed significant increase in the pressure peak and standard deviation with an increase in the flow turbulence. It was concluded that the roof mid-plane pressure sensitivity to the turbulence intensity was the cause of the previously reported field-laboratory mismatch of the fluctuating pressure, for wind normal and $30^{\circ}$-off normal to the building ridge. In addition, it was concluded that the cornering wind mismatch in the roof corner/edge regions could not be solely attributed to the wind-azimuth-independent discrepancy between the turbulence intensity of the approach field and laboratory flows.

Pressure Analyses at the Planar Surface of Liquid-Vapor Argon by a Test-Area Molecular Dynamics Simulation

  • Lee, Song-Hi
    • Bulletin of the Korean Chemical Society
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    • 제33권9호
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    • pp.3039-3042
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    • 2012
  • Pressure tensors at the planar surface of liquid-vapor argon are evaluated from the virial theorem, Irving-Kirkwood, and Harasima versions using a test-area molecular dynamics simulation method through a Lennard-Jones intermolecular potential at two temperatures. We found that the normal and transverse components of the pressure tensor, $p_N(z)$ and $p_T(z)$, obtained from the virial theorem and Harasima version are essentially the same. The normal component of the pressure tensor from Irving-Kirkwood version, $p_N^{IK}(z)$, is shown to be a nearly constant at the lower temperature, independent of z, as agreed in a previous study, but not for $p_N^H$(z), while the transverse components, $p_T^{IK}(z)$ and $p_T^H(z)$, are almost the same. The values of surface tension for both versions computed from $p_N(z)-p_T(z)$ are also the same and are fully consistent with the experimental data.

당뇨발 환자의 보행 시 발바닥 전단응력 및 압력분포 분석 (The analysis of plantar shear stress and pressure of diabetic foot patients during walking)

  • 황성재;박선우;김영호
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2005년도 추계학술대회 논문집
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    • pp.260-263
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    • 2005
  • In this study, we analyzed the plantar shear stress and pressure of diabetic foot patients during walking by using in-shoe local shear force and plantar pressure measurement system. Twelve normal subjects and three diabetic foot patients with diabetic neuropathy in lateral heel were participated in this study. The center of pressure in diabetic foot patients moved more medially and directed toward 1st, 2nd metatarsal heads and hallux during late stance period, making pressure at the medial heel and 2nd metatarsal head significantly higher than in the normal. Shear stress at the heel were changed significantly in early stance and the magnitude of shear stresses in each metatarsal head were also changed. Further studies would be very helpful to design foot orthoses in patients with diabetic neuropathy or other diseases.

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