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11.
A simple and accurate measurement of intraabdominal pressure is essential to predict a successful closure of defects in omphalocele and gastroschisis. Intravesical pressure (IVP) is a close estimation of intraabdominal pressure and can be measured safely by placing a catheter in the urinary bladder during surgery. Three neonates with gastroschisis and four with omphalocele were studied. Pressure-related complications such as ascites leakage, ventral hernia, impaired venous return of the lower extremities, and oliguria developed only in the patients with IVP > 20 mmHg after fascial closure. Prolonged hospitalization, ventilation support and intensive care were required for these patients. 相似文献
12.
Y.K. Chen M.C. Wu W.S. Hobson S.J. Pearton A.M. Sergent M.A. Chin 《Photonics Technology Letters, IEEE》1991,3(5):406-408
High-power lattice-strained AlGaAs/InGaAs graded index separate-confinement heterostructure (GRINSCH) quantum-well lasers emitting at a 980-nm wavelength have been grown by organometallic vapor phase epitaxy (OMVPE) and fabricated with a self-aligned ridge-waveguide structure. Using a 3- mu m-wide and 750- mu m-long AR-HR coated laser, 30 mV of optical power was coupled into optical fibers with 28.6% efficiency. A dominating single-lobe far-field radiation pattern was obtained from a wedge-shaped ridge-waveguide laser for output power as high as 240 mW with a maximum output power of 310 mW.<> 相似文献
13.
Chan K.T. Chin A. McAlister S.P. Chang C.Y. Liu J. Chien S.C. Duh D.S. Lin W.J. 《Electron Device Letters, IEEE》2003,24(1):28-30
Very-low-transmission line noise of <0.25 dB at 18 GHz and low power loss /spl les/0.6 dB at 110 GHz have been measured on transmission lines fabricated on proton-implanted Si. In contrast, a standard Si substrate gave much higher noise of 2.5 dB and worse power loss of 5 dB. The good RF integrity of proton-implanted Si results from the high isolation impedance to ground, as analyzed by an equivalent circuit model. The proton implantation is also done after forming the transmission lines at a reduced implantation energy of /spl sim/4 MeV. This enables easier process integration into current VLSI technology. 相似文献
14.
Equal Strain Consolidation by Vertical Drains 总被引:1,自引:0,他引:1
Chin Jian Leo 《Canadian Metallurgical Quarterly》2004,130(3):316-327
This paper shows the development of a series of closed-form solutions of equal strain consolidation in the presence of a vertical drain with smear and well resistance. Using an approach that considers the effects of both the radial and vertical drainage in a fully coupled fashion, solutions are obtained for the excess pore pressure and the degree of consolidation in the compressible soil subjected to a step- or ramp-loading situation. The closed-form solutions in the present paper may be evaluated in an electronic spreadsheet on a standard personal computer. 相似文献
15.
Chen Y.K. Wu M.C. Hong M.H. Mannaerts J. Chin M.A. Sergent A.M. 《Electron Devices, IEEE Transactions on》1991,38(12):2692-2693
Summary form only given. An edge-emitting strained AlGaAs/InGaAs/GaAs quantum-well laser structure is reported. It has a periodic index separate confinement heterostructure (PINSCH) optical confinement layers for a small beam divergence and high output power. Preliminary measurements of AR/HR-coated self-aligned ridge waveguide lasers show a CW output power of up to 350 mW and a 20° transverse beam divergence at a 980-nm lasing wavelength. This low beam divergence results in a high coupling efficiency of 51% into single-mode fibers. The expanded optical field in PINSCH confinement layers significantly pinches the transverse beam divergence and increases the maximum output power 相似文献
16.
An impedance matching technique using series condensers for the power receivers of in vivo robotic capsules is proposed. The power delivery function of the condenser ratio and its optimal ratio are derived. Experimental results validate the derived function. 相似文献
17.
The simultaneous contrast effect is investigated in this article. A total of 174 and 154 test/induction combinations were studied for CRT and surface colours respectively. Each combination was assessed by nine observers using a matching technique. The test and induction colours used for CRT colours were similar to surface colours using fabric samples. The results indicated a strong lightness contrast effect for both CRT and surface media; that is, the lightness of a test colour surrounded by a lighter induction colour was reduced for both CRT and surface colours. However, the effect in CRT medium was more pronounced than in the surface medium. © 2004 Wiley Periodicals, Inc. Col Res Appl, 30, 13–20, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/col.20074 相似文献
18.
Han‐Lang Wu Chen‐Chi M. Ma Chun‐Chieh Lin Yie‐Chan Chiu Chih‐Yuan Chen Chin‐Lung Chiang 《应用聚合物科学杂志》2008,107(5):3236-3243
Poly(arylene ether benzonitrile) (PAEBN) was synthesized with 2,6‐dichlorobenzonitrile and biphenol. PAEBNs with various molecular weights (MWs), 1,640,000 and 185,000 g/mol, were synthesized by control of the stoichiometry of the monomers and were blended with sulfonated poly(ether ether ketone) (SPEEK). The effects of MW on the water uptake, swelling, methanol permeability, and proton conductivity of the SPEEK/PAEBN blend membranes were investigated. The molecular mobility of the SPEEK/PAEBN blends was also examined in this study. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
19.
While the osteopenia associated with oestrogen deficiency is thought to arise from a relative defect in bone formation with respect to resorption, oestrogen administration itself leads to a decrease, rather than an increase, in bone formation. This decrease in bone formation, which arises from oestrogen's inhibitory effect on bone turnover, presumably masks any underlying tendency of oestrogen treatment towards stimulation of bone formation. To investigate this further, we have examined the early effect of discontinuing the administration of oestradiol-17 beta (OE2; 40 micrograms/kg) on bone formation indices in ovariectomized 13-week-old rats, before the turnover-induced increase in formation occurs. Histomorphometric indices were assessed at the proximal tibial metaphysis 0, 7, 10, 13 and 16 days following discontinuation of OE2 treatment. Measurements of body weight, uterine weight and longitudinal growth rate confirmed that there were rapid effects of OE2 deficiency on these parameters. We could detect no significant increase in bone resorption, as measured by osteoclast surface and number, until 16 days after ending treatment with OE2; this was coincidental with a reduction in bone volume. Shorter periods of OE2 deficiency were associated with a marked decrease in bone formation, as assessed by dynamic histomorphometric indices. This inhibition of bone formation was largely due to a reduction in double fluorochrome-labeled trabecular surfaces, which were decreased by approximately 70%. We conclude that ending OE2 administration in ovariectomized rats caused a striking decrease in trabecular bone formation, if such indices are assessed prior to the subsequent turnover-induced increase in formation.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
20.
Moon-chul Yoon Do-hun Chin 《The International Journal of Advanced Manufacturing Technology》2006,29(11-12):1125-1133
To analyze the chatter mechanics, the power spectrum of a time series method was analyzed by considering cutting and structural dynamics. In this study, several time series models such as AR (burg, least square, yule walker, geometric lattice, instrument variable), ARX (arx, iv4), ARMAX, ARMA, Box Jenkins, Output Error were modeled and compared with one another. Finally, it was proved that arx, armax and iv4 are more desirable and reliable algorithms than the others for the calculation of the chatter mode in the endmilling operation. The cutting forces Fx and Fz have more powerful effects on the chatter than Fy in the sense that there is no shifting or pseudo mode in the power spectrum. 相似文献