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101.
M Hayashida K Ogawa Y Kawashima R Isoda M Sato C Fujimura T Yoneyama S Sawamura 《Canadian Metallurgical Quarterly》1998,47(8):933-938
The bed bath procedure consists of cleansing patients' body, passive position change, changing gown and making a bed. During the procedure, mixed venous desaturation was observed consistently in postoperative cardiac patients. We investigated the cause of the phenomenon in 22 patients undergoing cardiac surgery in their first postoperative day. The patients were breathing oxygen-enriched air via a Venturi mask. Cardiac index (CI), transluminal SvO2, arterial blood gas, Hb, DO2, VO2, FIO2, A-aDO2 and Qp/Qs were measured before and during the bed bath, while the patients were in the supine and left lateral position, respectively. Mean 8.5 +/- 1.5 minutes were required to complete the bed bath. During the bed bath, SvO2 decreased from 71 +/- 7% to 59 +/- 9% (P < 0.001), and returned to the baseline 6.5 +/- 7.4 minutes after the completion of the bed bath. VO2 increased markedly from 128 +/- 27 to 194 +/- 47 ml.min-1.m-2 (P < 0.001), while DO2 increased slightly from 480 +/- 91 to 513 +/- 110 ml.min-1.m-2 (P < 0.05). Among the determinants of DO2, CI increased slightly from 3.3 +/- 0.6 to 3.6 +/- 0.8 l.min-1.m-2, Hb remained unchanged and SaO2 decreased from 98.5 +/- 0.8 to 98.0 +/- 1.1%. FIO2 also decreased, while A-aDO2 and Qp/Qs remained unchanged. There was a negative correlation between VO2 change and SvO2 change, but no correlation between DO2 change and SvO2 change. There was a positive correlation between SaO2 change and SvO2 change, as well as between FIO2 change and SaO2 change. Therefore, the major cause of mixed venous desaturation was not the decreased DO2 or cardiopulmonary decompensation but the increased VO2 due to increased activity of the skeletal muscles. However, the decrease in SaO2 due to markedly increased O2 demand and the limited increase in CI might partially contribute to the marked decline in SvO2 through the limited increase in DO2. 相似文献
102.
Manabu Sato Tatsuo Yamamoto Toshiyasu Meguro Kazuhiko Yamanouchi 《Sensors and actuators. B, Chemical》1994,20(2-3):205-212
The sensitivity, transient response and sensitivity mechanism of a surface acoustic wave humidity sensor using porous anodically oxidized aluminium (alumina) films as mechanical interfaces have been studied theoretically and experimentally. It is found that the sensitivity of alumina films of 1.0 μm thickness is -0.034 m/(s %RH) and is the same order as that of polyimide films. The transient response of alumina films to humidity is about one order faster than that of polyimide films. For the sensitivity mechanism, the phase-velocity change is attributed to the mechanical perturbation caused by the absorption of water molecules. The equivalent density change of alumina films between 0 and 100%RH is about 0.7%. In addition, the actual stiffness constants of alumina films are two orders less than those of bulk alumina. 相似文献
103.
This paper proposes a novel human-robot symbiosis system named a Robotic Office Room (ROR). The understanding, recording and retrieving of telephone call behavior are successfully demonstrated as a typical example of an office work-supporting function of ROR. A unique object model is proposed, which accumulates information concerning motion of the object. This model enables the system to understand human behavior, not by monitoring the motion of the human, but by monitoring the motion of the object-typically, a telephone or pen. Since the model requires the system to pay spatial and temporal attention only to the target object and related motions, it saves computing power. Repertoires of understandable behavior can easily be expanded by simply adding new object models. The ROR is equipped with networked machines. The concept of "ubiquitous link" consisting of unique image channels and remote control channels is proposed. The image channel and the remote control channel utilize TV images and either ultrasonic waves or infrared rays, respectively. Such cooperative support of humans by networked machines is realized that when a human starts to talk on the phone, the ROR not only starts to record the image of the human's behavior, utilizing a VCR, but also turns down the volume on an audio set. The experiment proved the feasibility of the ROR as an integrated robotic system to support human office work. 相似文献
104.
Yamakoshi Y Sato J Sato T 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》1990,37(2):45-53
An imaging system that can display both the amplitude and phase maps of internal vibration in soft tissues for forced low-frequency vibration is described. In this method, low-frequency sinusoidal vibration of frequency under several hundred hertz is applied from the surface of the sample and the resulting movement in it is measured from the Doppler frequency shift of the simultaneously transmitted probe ultrasonic waves. Basic experiments are carried out by using 3.0-MHz ultrasonic waves. The two-dimensional maps of the amplitude and phase of internal vibration are shown, and the velocities of vibration are measured for some samples as well as in vivo. 相似文献
105.
Tae Hyon Kim Kiyohiro Goto Hiroki Igarashi Kazuyuki Kon Noritaka Sato Fumitoshi Matsuno 《Artificial Life and Robotics》2012,16(4):514-518
Recently, many research projects and competitions have attempted to find an autonomous mobile robot that can drive in the
real world. In this article, we consider a path-planning method for an autonomous mobile robot that would be safe in a real
environment. In such a case, it is very important for the robot to be able to identify its own position and orientation in
real time. Therefore, we applied a localization method based on a particle filter. Moreover, in order to improve the safety
of such autonomous locomotion, we improved the path-planning algorithm and the generation of the trajectory so that it can
consider a region with a limited maximum velocity. In order to demonstrate the validity of the proposed method, we participated
in the Real World Robot Challenge 2010. The experimental results are given. 相似文献
106.
Crystallization of potassium titanate from the amorphous phase 总被引:1,自引:0,他引:1
Tadashi Endo Hiroyuki Nagayama Tsugio Sato Masahiko Shimada 《Journal of Materials Science》1988,23(2):694-698
By using amorphous potassium titanates as the starting materials, a sintered body of K2Ti4O9 or K2Ti6O13 with porous and fibrous textures was prepared. K2Ti2O5 and a new phase, K6Ti4O11 were synthesized by the thermal reaction of KNO3 with TiO2 at 1000° C for 10 to 20 h. On leaching in water to expel excess of potassium ions, both phases became amorphous. After mixing and moulding these amorphous materials in the desired proportion, a sintered body containing fibrous crystals of K2Ti4O9 was readily fabricated by heating at 1000° C for 12 h. When 5 wt % B2O3 was added to the amorphous phases, single phase K2Ti6O13, with a fibrous texture grew well on heating at 1000° C for 12 h. Addition of PVA polymer to the amorphous phases was responsible for controlling the porosity of the sintered body, e.g. about 52% theoretical density at 20 wt% PVA polymer. The optimum conditions for preparing the amorphous phases were systematically examined and the effect of the chemical reaction environments, such as different crucible materials on the calcination of KNO3 and TiO2 were also discussed. 相似文献
107.
Iron powders were oxidized in NaOH solutions of 5–25 mol kg–1 at 403–563 K and 5 MPa of oxygen partial pressure. Various types and morphologies of iron compounds such as fine particles of Fe3O4, micaceous -Fe2O3, and coagulated particles of -NaFeO2 were formed depending on the experimental conditions. The observed critical concentrations of NaOH above which -NaFeO2 was formed was in good agreement with those thermodynamically calculated for the hydrolysis equilibrium of -NaFeO2. 相似文献
108.
Experimental vapor pressures andP--T data of an important alternative refrigerant, 1, 1-difluoroethane (HFC-152a), have been measured by means of a constant-volume method coupled with expansion procedures. SixtyP--T data were measured along eight isochores in a range of temperaturesT from 330 to 440 K, at pressuresP from 1.6 to 9.3 MPa, and at densities from 51 to 811 kg·m–3. Forty-six vapor pressures were also measured at temperatures from 320 K to the critical temperature. The uncertainties of the temperature and pressure measurements are within ±7mK and ±2kPa, respectively, while the uncertainty of the density values is within ±0.1%. The purity of the sample used is 99.9 wt%. On the basis of the measurements along each isochore, five saturation points were determined and the critical pressure was determined by correlating the vapor-pressure measurements. The second and third virial coefficients for temperatures from 360 to 440 K have also been determined. 相似文献
109.
Metal nitrides and carbides powders were synthesized by the spark discharge method in liquid ammonia at 100 °C and 11 kV of the spark discharge voltage and in n-heptane at 25 °C and 7.5 kV using the pellets of aluminum, titanium, iron and chromium as the starting material. The main products were AlN, TiN0.51, -Fe, -Cr2N in liquid ammonia, and Al4C3, TiC, -Fe, Fe2C and Cr7C3 in n-heptane. The agglomerated particle size decreased with increasing melting point of the metal used as the starting material. 相似文献
110.