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1.
Shopping on the Internet enables consumers to search for information on products or services and make purchases through direct interaction with online retailers. This study investigates consumer shopping behaviour on the Internet based on four aspects, i.e. the Internet marketing environment, product characteristics, familiarity, and promotional offers. The impact of influencing factors was checked by questionnaire survey, which was then processed and evaluated. Two hundred randomly selected respondents (students and employees in a public higher learning institution in the Federal Territory of Labuan, Malaysia) participated in the survey. Multiple regression analysis was used as a statistical measure to determine the most influential relationship aspect among a series of independent variables of consumer shopping on the Internet. The results revealed that familiarity has a great influence on consumer shopping on the Internet, followed by promotional offers. The assimilation of these aspects, and the empirical examination of the factors that influence consumer shopping on the Internet, advanced understanding of these constructs and their link to dynamic technology deployment for shopping. The paper suggests managerially actionable implications, and future research directions.  相似文献   
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Eleven patients with chronic renal failure and presumed secondary hyperparathyroidism developed a syndrome of medial calcinosis of the arteries and painful ischemic ulcers of the fingers, legs, or thighs, or any combination of the three. Five patients required maintenance hemodialysis; six had functioning renal homografts. Severe hyperphosphatemia had existed in each; seven showed roentgenographic evidence of subperiosteal resorption. Similarities are evident between the lesions and experimentally produced calciphylaxix. The lesions demonstrated a relentless, progressive course, with serious morbidity and mortality. Hyperplastic or adenomatours parathyroid tissue was removed from ten of 11 patients unergoing surgical procedures; healing followed in seven patients. Treatment with phosphate-binding antacids to lower serum phosphorus levels may prevent this syndrome. Total or subtotal parathyroidectomy should be considered when ischemic skin lesions appear in uremic patients or in renal transplant recipients.  相似文献   
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A new column redundancy scheme is presented that can minimise the die area overhead by repair circuits and also achieve fast access speed in high density dynamic random access memories (DRAMs) with wide data widths. The proposed scheme has a large redundancy-area-unit (RAU) which operates a flexible column redundancy scheme that consecutively shifts RDQ (redundant I/O) to neighbouring MDQ (main I/O) without any speed penalty. By using the proposed mapping fuse algorithm. The number of fuses required to store the fail bit address can be reduced, and the chip area reduced.  相似文献   
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In this paper, interface circuits that are suitable for point‐to‐point interconnection with an over 1 Gbps data rate per pin are proposed. To achieve a successful data transfer rate of multi‐gigabits per‐second between two chips with a point‐to‐point interconnection, the input receiver uses an on‐chip parallel terminator of the pass gate style, while the output driver uses the pullup and pulldown transistors of the diode‐connected style. In addition, the novel dynamic voltage level converter (DVLC) has solved such problems as the access time increase and valid data window reduction. These schemes were adopted on a 64 Mb DDR SRAM with a 1.5 Gbps data rate per pin and fabricated using a 0.10 µm dual gate oxide CMOS technology.  相似文献   
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This paper presents a transmitter and receiver for magnetic resonant wireless battery charging system. In the receiver, a wide-input range CMOS multi-mode active rectifier is proposed for a magnetic resonant wireless battery charging system. The configuration is automatically changed with respect to the magnitude of the input AC voltage. The output voltage of the multi-mode rectifier is sensed by a comparator. Furthermore, the configuration of the multi-mode rectifier is automatically selected by switches as original rectifier mode, 1-stage voltage multiplier or 2-stage voltage multiplier mode. As a result, a rectified DC voltage is output from 7.5 to 19 V for an input AC voltage of 5–20 V. In the transmitter, a class-E power amplifier (PA) with an automatic power control loop and load compensation circuit is proposed to improve the power efficiency. The transmitted power is controlled by adjusting the signal applied to the gate of the power control transistor. In addition, a parallel capacitor is also controlled to enhance the efficiency and compensate for the load variation. This chip is implemented using 0.35 μm BCD technology with an active area of around 5,000 × 2,500 μm. When the magnitude of the input AC voltage is 10 V, the power conversion efficiency of the multi-mode active rectifier is about 94 %.The maximum power efficiency of the receiver is about 70 %. The transmitter provides an output power control range of 10–30.2 dBm. The maximum power efficiency of the PA is 71.5 %.  相似文献   
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The plasma membrane Ca-ATPases play an important role in the regulation of intracellular Ca2+ ion concentration by pumping Ca2+ out of the cell into the extracellular fluid at the expense of ATP. These pumps potentially play an important role in the delivery of Ca2+ during mineralization of hard tissues such as bone. The properties of the plasma membrane Ca2+ pump are compared with those of the sarco(endo)plasmic reticulum and the factors regulating pump function are presented. The different gene products for the plasma membrane Ca-ATPases are described as well as their known functional significance. Particular attention is paid on the plasma membrane Ca2+ pumps present in mineralizing tissues and evidence supporting a role for these pumps in the transcellular delivery of Ca2+ during the process of mineralization is also presented.  相似文献   
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It has been proposed that during mild-to-moderate bronchoconstriction one can partition airway and tissue properties on the basis of input impedance (Zin) acquired from 0.1 to 5 Hz (K.R. Lutchen, B. Suki, Q. Zhang, F. Peták, B. Daróczy, and Z. Hantos. J. Appl. Physiol. 77: 373-385, 1994). The approach is to apply a homogeneous lung model that contains airway resistance and viscoelastic tissue damping and elastance parameters. The tissue parameters account for the frequency dependence in lung resistance (RL) and elastance (EL). We present an anatomically consistent asymmetrically branching airway model to address two key questions: 1) How will lung inhomogeneities, airway wall shunting, and tissue viscoelasticity contribute to increased frequency dependence and levels of RL and EL during lung constriction? and 2) How much can lung inhomogeneities and airway wall shunting contribute to our assessment of airway, tissue, and overall lung properties derived from Zin? The model incorporates nonrigid airway walls and allows for explicit control over the type and degree of inhomogeneous airway constriction or tissue changes. Our results indicate that, from 0.1 to 5 Hz, airway wall shunting does not become important unless the entire lung periphery experiences significant constriction. Mild-to-moderate inhomogeneous peripheral airway constriction produces a relatively minor additional frequency dependence in RL and EL beyond that due to the tissues alone. With more extreme constriction, however, there is a marked frequency-dependent increase in EL. This phenomenon may render it impossible to distinguish from a single frequency measurement whether an increase in EL during bronchoconstriction is a consequence of a true increase in tissue stiffening or simply a consequence of airway phenomena. Finally, Zin from 0.1 to 5 Hz can be used to provide a reasonable separation of airway and tissue properties for mild-to-moderate homogeneous or inhomogeneous lung constriction. However, during more severe disease, inhomogeneities and/or wall shunting will produce substantial overestimation of tissue damping and hysteretic properties. In fact, the only reliable indicator of a real change in the tissues may be a change in the estimate of tissue elastance that is based on data extending to a sufficiently low frequency.  相似文献   
10.
Suki  明天 《半导体技术》2004,29(11):17-18
10月的深圳沉浸在欢乐的海洋,纳八方来客的第五届国际园林博览会还在如火如荼的进行着,"一方未休,另方登场",10月12日随着2000发烟弹腾空而起,天空绽放五彩祥云,中国规模最大、在国际上颇具影响力的国家级、国际性的大型科技成果交易盛会--第六届中国国际高新技术成果交易会开幕了.在这欢乐的时刻,我们<半导体技术>有幸采访了瑞萨半导体管理(中国)有限公司的董事长、总裁小仓节生先生.  相似文献   
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