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81.
设计的功能是以人为本,丰富和升华人们的生理体验和心理体验以提升生活品质,传递信息和新的思维方式;设计作品的优劣从某种角度来说是设计思维深入程度决定的;设计思维是以个人对世界的认识为基础的;人对世界认识的程度实际上也就是设计思维深入的程度,因此我们应弄清自己思维的渊源,树立正确的世界观。  相似文献   
82.
设计的功能是以人为本,丰富和升华人们的生理体验和心理体验以提升生活品质,传递信息和新的思维方式;设计作品的优劣从某种角度来说是设计思维深入程度决定的;设计思维是以个人对世界的认识为基础的;人对世界认识的程度实际上也就是设计思维深入的程度,因此我们应弄清自己思维的渊源,树立正确的世界观。  相似文献   
83.
采用单片机进行智能控制 ,实现喷淋座垫智能化 ,克服了以往人工调整水杆和人工限时的弊病 ,提高了产品的性能和实用价值。  相似文献   
84.
The innervation of the duodenal enterochromaffine cells (E.C.) of the guinea pig was studied at the electronmicroscopic level. Pretreatment with 5-OH-dopamine was performed to visualize catecholaminergic (CA) nervous elements. Near the basement membrane of all examined E.C. in the crypts, bundles of unmyelinated nerve processes were observed, only partly ensheathed in a Schwann cell cover. At least 4 types of processes could be observed. 1) Boutons containing only small clear vesicles, probably cholinergic fibres; 2) boutons with small clear vesicles, and in addition large (greater than 200 nm) granules with a dense matrix (P-type-fibres); 3) boutons with small electron-dense vesicles, probably CA-fibres; and 4) processes with few vesicles but having the appearance of dendrites. No typical synaptic arrangements were observed, but the minimal distance between the E.C. and the nerve bundles was 150 to 250 nm, thus well within the functional limits of the "autonomic gap". Thus epithelial E.C. may be influenced by several types of nervous elements, including CA-fibres.  相似文献   
85.
The creep behaviour of polyvinyl chloride (PVC) has been studied in the temperature range 280 to 340° F under constant stress varying from 3.4 to 22.7 p.s.i. It is shown that the steady-state creep rate is an exponential function of stress as suggested by Norton but the exponent decreases with temperature. The activation energy for creep is determined using an activated-state rate process and it is found to be a decreasing function of stress with a higher value at temperatures 320° F and above. It is shown that the time dependent strain can be represented by $$\gamma = \gamma _0 + \dot \gamma _s t + \gamma _T \left[ {1 - \exp \left( { - K\dot \gamma _s t} \right)} \right]$$ where γ 0 is the instantaneous strain on stressing, \(\dot \gamma _s\) the secondary creep rate, γ T transient strain, and K is a constant. Scanning electron micrograph studies of the fracture surface and the change in activation energy apparently support the probability of two different deformation mechanisms i.e., domain flow and chain segmental or molecular flow at temperatures below and above 320° F, respectively.  相似文献   
86.
There is as yet no specific treatment for viral hepatitis, and in an uncomplicated course no further action apart from moderate bedrest is necessary. The patient should however, be isolated in a special ward. In fulminant hepatic failure the benefit of glucocorticoid therapy is still controverted and appears to depend on an early beginning. Treatment with HBsAg-rich human serum in fulminant hepatitis B is still under evaluation. In chronic active hepatitis the administration of azathioprine in combination with glucocorticoids is highly effective, and it appears to be irrelevant whether HBsAg is present in plasma or not; however, the best results have been achieved in "lupoid" hepatitis. The use of transfer factor, laevamisol or thymosin to suppress T-cell action on antibody production of the B-cells cannot yet be finally evaluated with respect to its effectiveness in chronic active hepatitis. Prevention is of major importance in solving the problems involved in hepatitis B infections. Recent experience with active immunization using HBsAg-rich sera or purified formalin inactivated HBsAg preparations suggest the possibility of successful vaccination against hepatitis B in the near future, but the precondition for obtaining sufficient quantities of vaccine is to find suitable culture media for the virus.  相似文献   
87.
哈岸英  吴腾  陈刚 《水利学报》2012,43(1):10-14
通过理论分析与数值计算,研究了冲积河流漫滩水流水力因子的变化特性。结果表明,断面平均流速在漫滩瞬间迅速减小,然后逐渐增大;断面综合动能修正系数、动量修正系数均随水深而缓慢增加,在漫滩瞬间迅速增大,随即快速减小。根据漫滩水流水力因子沿水深的变化特性,提出采用断面横向平均流速为判别因子以定量划分复式断面的滩与槽。此外,文中将其应用于黄河下游漫滩水流的水沙数值模拟,其结果与实际情况符合较好。  相似文献   
88.
Streaming video over a wireless network faces several challenges such as high packet error rates, bandwidth variations, and delays, which could have negative effects on the video streaming and the viewer will perceive a frozen picture for certain durations due to loss of frames. In this study, we propose a Time Interleaving Robust Streaming (TIRS) technique to significantly reduce the frozen video problem and provide a satisfactory quality for the mobile viewer. This is done by reordering the streaming video frames as groups of even and odd frames. The objective of streaming the video in this way is to avoid the losses of a sequence of neighbouring frames in case of a long sequence interruption. We evaluate our approach by using a user panel and mean opinion score (MOS) measurements; where the users observe three levels of frame losses. The results show that our technique significantly improves the smoothness of the video on the mobile device in the presence of frame losses, while the transmitted data are only increased by almost 9% (due to reduced time locality).  相似文献   
89.
文中主要分析了沧州南部典型区近30年来气温演变情势,分析了其统计特征、年内变化趋势性和年代际变化、持续性、突变性和周期性,得出了一定的规律性,为深入研究本区域与气温有关的课题打下了基础。  相似文献   
90.
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