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1.
Co-browsing is an activity in which a group of users navigate their way through of a set of Web pages together for a shared purpose. Effective co-browsing among users with different device capabilities requires a shared understanding of those Web pages. This paper demonstrates the concept of shared viewpoints (SVPs), and personal viewpoints (PVPs), for co-browsing, before detailing a framework for implementing these concepts. Finally, the effectiveness of the framework is presented through a perceptual experiment.  相似文献   
2.
The combination of device speed (f/sub T/, f/sub max/ > 150 GHz) and breakdown voltage (V/sub bceo/ > 8 V) makes the double heterojunction bipolar InP-based transistor (D-HBT) an attractive technology to implement the most demanding analog functions of 40-Gb/s transceivers. This is illustrated by the performance of a number of analog circuits realized in an InP D-HBT technology with an 1.2- or 1.6-/spl mu/m-wide emitter finger: a low phase noise push-push voltage-controlled oscillator with -7-dBm output power at 146 GHz, a 40-GHz bandwidth and low-jitter 40-Gb/s limiting amplifier, a lumped 40-Gb/s limiting driver amplifier with 4.5-V/sub pp/ differential output swing, a distributed 40-Gb/s driver amplifier with 6-V/sub pp/ differential output swing, and a number of distributed preamplifiers with up to 1.3-THz gain-bandwidth product.  相似文献   
3.
This study was designed to address three objectives in an experimental model of acute congestive heart failure (CHF) in the dog produced by rapid ventricular pacing. The first objective was to characterize cardiorenal and humoral responses before and during 2 h of acute CHF. The second objective was to determine the modulating action of iv furosemide upon these biologic responses to acute CHF, testing the hypothesis that furosemide-mediated natriuresis is associated with activation of the renin-angiotensin-aldosterone system (RAAS) compared with the control group. The third objective was to determine the modulating action of continuous low-dose atrial natriuretic factor (ANF) administration during acute CHF upon these biologic responses, testing the hypothesis that exogenous low-dose ANF would prevent activation of the RAAS and enhance the natriuretic action of furosemide. In the control group (Group 1; N = 6), plasma ANF increased after the onset of CHF; GFR and sodium excretion were maintained without activation of this RAAS despite arterial hypotension. In Group 2 (N = 6), furosemide in acute CHF increased sodium excretion but in association with a decrease in GFR and activation of the RAAS. Low-dose exogenous ANF and furosemide (Group 3; N = 6) in acute CHF were associated with a maintenance of GFR, no activation of the RAAS, and potentiation of furosemide-induced natriuresis. In summary, these studies demonstrate that furosemide potently increases sodium excretion in acute CHF, but with a decrease in GFR and activation of the RAAS. Low-dose ANF in acute CHF with furosemide maintains GFR, attenuates activation of the RAAS, and potentiates natriuresis.  相似文献   
4.
The continuous reduction of chip size driven by the market demand has a significant impact on circuit design and assembly process of IC packages. Shrinking chip size and increasing I/O counts require finer bond pad pitch and bond pad size for circuitry layout. As a result, serious wire deflection during transfer molding process could make adjacent wires short, and this issue becomes more critical as a smaller wire diameter has to be applied for the finer pitch wire bonded IC devices.This paper presents a new encapsulation process development for 50 μm fine pitch plastic ball grid array package. Since reduced wire diameter decreases the bending strength of bonded wires significantly, wire deflection during molding process becomes quite serious and critical. Experiments on conventional transfer molding were conducted to evaluate wire span threshold with 23.0 μm diameter gold wire. The results show that the wire span threshold is about 4.1 mm, which is much shorter than the wire span threshold of over 5.0 mm for wire with 25.4 μm diameter. Finite element analysis shows there is a significant difference in the wire deflection between 23.0 μm gold wire and 25.4 μm gold wire diameter under the same action of mold flow. A novel encapsulation method is introduced using non-sweep solution. The wire span could be extended to over 5.0 mm with wire sweep less than 1%. Reliability tests conducted showed that all the units passed 1000 temperature cycles (−55 to 125 °C) with JEDEC moisture sensitivity level 2a (60 °C/60% relative humidity for 120 h) and 3 times reflow (peak temperature at 220–225 °C). It is believed that this solution could efficiently overcome the risk of wire short issues and improve the yield of ultra fine pitch wire bonds in high-volume production.  相似文献   
5.
Godfrey Chua   《Refocus》2003,4(6):965-28
The Asia-Pacific region is one of the fastest growing regional economies in the world today. The region is home to over half of the global population and is one of the most important markets for multinational corporations to penetrate. The wind power sector is no exception. Wind resources remain untapped and the demand for electricity continues to grow as a result of expanding and modernizing economies. Godfrey Chua, Emerging Energy Research USA reports on the current status and development of the wind industry in the region.  相似文献   
6.
Pull-out experiments have been carried out on single production fibres under carefully controlled conditions. Four parameters were determined. The interfacial yield stresses, of about 9–14 MPa, were very much smaller than the shear strengths of the bulk polymers in the case of an epoxy, whether post-cured or not, and a non-post-cured polyester. Values for the work of fracture of the interface varied from 140 to 300 Jm?2, and again were less than those of the polymer. Interface failure sometimes took place in the epoxy rather than at the fibre surface, whereas with the polyester it always took place at the fibre surface. After interface failure, pull-out was governed by friction, with maximum shear stresses of 7–10 MPa for polyester, and 21–34 MPa for epoxy, the higher values being obtained for the post-cured resins. Average frictional shear stresses were sometimes less than a half of the maximum shear stress, indicating that the fibre Poisson's shrinkage was playing an important role in the pull-out process. A silicone release agent reduced the frictional shear stresses to 2·5 MPa, with both resins.  相似文献   
7.
Mantle cell lymphoma (MCL) is a relatively uncommon yet distinct type of malignant lymphoma whose clinical and pathological characterization has been limited by the small numbers of cases published to date. We studied 80 cases of MCL seen at a single institution over 7 years to determine both clinical and pathological prognostic factors. The patients in this study were predominantly male (70%) and older (mean age, 63 years) and presented with advanced-stage disease (88%). Extranodal involvement was common. Median overall survival (OS) was 43 months. Except for performance status, prognosis was not significantly influenced by clinical prognostic factors. Histologically, MCL architecture was classified as diffuse (78%), nodular (16%), or mantle zone (6%); the OS among these groups was identical. Increased mitotic activity (>20 mitotic figures per 10 high power fields), blastic transformation, and peripheral blood involvement at diagnosis also predicted for a worse outcome, but bone marrow involvement did not. The presence or absence of a translocation t(11; 14) by cytogenetic analysis or a bcl-1 rearrangement by Southern analysis did not significantly predict outcome. In summary, this study of 80 cases of MCL highlights its distinctive clinicopathologic features and shows that increased mitotic activity, blastic morphology, and peripheral blood involvement at diagnosis are prognostically important factors.  相似文献   
8.
This paper presents 5 patients with repeated recurrence of osteosarcoma (RROS). The primary focus of 3 patients were in the distal portion of femur, and 2 patients were in the proximal portion of tibia. Three patients, whose chest X ray film were negative, were treated by amputation and chemotherapy. Two patients had isolated metastatic focus 1.5 cm in diameter in lung, were treated by amputation after 1 week of chemotherapy and then treated by lobectomy after 2 weeks of chemotherapy. After operation, the chemotherapy was carried out for 3 courses of treatment. The roentgenogram of chest and affected limb were taken once every two months. There were metastatic focuses found in the lung of 1 patient and in the distal portion of femur of 2 patients. One patient was operated on for 4 times. Up to now, 3 patients have been living for 5 years and 2 patients for 6 years after operation.  相似文献   
9.
The vast majority of recombinant polytropic murine leukemia viruses (MuLVs) generated in mice after infection by ecotropic MuLVs can be classified into two major antigenic groups based on their reactivities to two monoclonal antibodies (MAbs) termed Hy 7 and 516. These groups very likely correspond to viruses formed by recombination of the ecotropic MuLV with two distinct sets of polytropic env genes present in the genomes of inbred mouse strains. We have found that nearly all polytropic MuLVs identified in mice infected with a substrain of Friend MuLV (F-MuLV57) are reactive with Hy 7, whereas mice infected with Moloney MuLV (Mo-MuLV) generate major populations of both Hy 7- and 516-reactive polytropic MuLVs. We examined polytropic MuLVs generated in NFS/N mice after inoculation with Mo-MuLV-F-MuLV57 chimeras to determine which regions of the viral genome influence this difference between the two ecotropic MuLVs. These studies identified a region of the MuLV genome which encodes the nucleocapsid protein and a portion of the viral protease as the only region that influenced the difference in polytropic-MuLV generation by Mo-MuLV and F-MuLV57.  相似文献   
10.
Blood flow is a critical parameter for obtaining satisfactory temperature distributions during clinical hyperthermia. This study examines the changes in blood flow distribution in normal porcine skeletal muscle before, during and after a period of regional microwave hyperthermia. The baseline blood flow distribution during general anaesthesia and after the insertion of the thermal probes was established independently in order to isolate the changes due to hyperthermia. General anaesthesia alone and thermocouple insertion during anesthesia had no significant effect on the muscle blood flow distribution. Regional microwave heating generated a non-uniform blood flow distribution which was a function of the tissue temperature distribution. Blood flow was greater in those tissues samples in which higher temperatures were recorded and less in those sampled further from the applicators peak SAR (Specific Absorption Rate). The increase in blood flow appears to be primarily a local phenomenon. Although muscle blood flow may be considered to be uniform prior to heating, this does not hold during hyperthermia treatment. Therefore, the non-uniform nature of the blood distribution during heating should be incorporated into any practical bioheat transfer model.  相似文献   
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