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11.
Efforts toward defining a standard for workflow interoperability began in 1994 with the Workflow Reference Model from the Workflow Management Coalition (WfMC). From that model other standardization efforts have evolved: from OMG's jointflow specification to the simple Workflow Access Protocol. The WfMC's Wf-XML focuses on a simple subset of SWAP for a first version of a standard, with the aim of future extension  相似文献   
12.
In this paper we report on the fabrication and characterization of SrHfO(3):Ce ceramics. Powders were prepared by solid-state synthesis using metal oxides and carbonates. X-ray diffraction measurements showed that phase-pure SrHfO(3) is formed at 1200°C. Inductively coupled plasma spectroscopy confirmed the purity and composition of each batch. SrHfO(3) exhibits several phase changes in the solid, but this does not appear to be detrimental to the ceramics. Microprobe experiments showed uniform elemental grain composition, whereas aluminum added as charge compensation for trivalent cerium congregated at grain boundaries and triple points. Radioluminescence spectra revealed that the light yield decreases when the concentration of excess Sr increases. The decrease in the light yield may be related to the change of Ce(3+) into Ce(4+) ions. For stoichiometric SrHfO(3):Ce, the light yield is about four times that of bismuth germanate (BGO), the conventional benchmark, indicating great potential for many scintillator applications.  相似文献   
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14.
Ohne ZusammenfassungMitteilung aus dem Landwirtschaftlich-Bakteriologischen Laboratorium des Ackerbauministeriums zu St. Petersburg (Direktor: M. G. Tartakowsky).  相似文献   
15.
PURPOSE: This retrospective study was performed to assess the treatment outcome and prognostic factors in 101 men with invasive squamous carcinoma of the penis treated at the Royal Marsden Hospital between 1960-1990. METHODS AND MATERIALS: The tumor was confined to the glans penis (T1) in 79 patients, 82 were node negative (N0), and two patients had distant metastases at presentation. The histology was Grade 1 (G1) in 36, Grade 2 (G2) in 18, Grade 3 (G3) in 28, and unknown in 19 patients. Node-positive disease was commoner in patients with G3 (p = 0.02) or T2/3/4 tumors (p = 0.007). Treatment for the primary tumor was external beam radiotherapy (EBRT) in 59, interstitial brachytherapy in 13, and partial or total penectomy in 29 patients. The median dose, dose/fraction, and treatment time for EBRT was 60 Gy, 2 Gy/fraction, and 46 days, respectively. Eighty patients received no inguinal node treatment, 13 had EBRT (4 with chemotherapy), and 8 underwent groin dissection at presentation. RESULTS: During a median follow-up of 5.2 years (2 months-22 years), 56 patients died (penile cancer 31, intercurrent illness 23 and unknown cause 2), giving 10 year overall and cause-specific survival (CSS) of 39 and 57%, respectively. Adverse prognostic factors for CSS on univariate analysis were G3, ulcerative/fungating or T2/3/ 4 tumors, node positive, Jackson's Stage 2/3/4, and surgical treatment for the primary. All but the last two were significant independent prognostic factors for CSS on multivariate analysis. Penile or perineal recurrence or residual disease after initial treatment was seen in 36 out of 98 evaluable patients, giving a 10-year local failure rate (LFR) of 45%. Local failure after initial treatment was successfully salvaged in the majority (26 out of 36) of patients with further surgery or radiotherapy, and local control was achieved ultimately in 74 out of 77 T1, 7 out of 12 T2; 3 out of 3 T3, and 3 out of 5 T4 tumors. In the 44 evaluable patients with T1 tumors treated by EBRT the only adverse RT parameter approaching prognostic significance (p = 0.052) was a BED value corrected for recovery of <60 Gy (alpha/beta 10, K = 0.5 Gy/day, mean = 21 days). CONCLUSION: Invasive squamous carcinomas of the penis carry a significant risk of loco-regional recurrence after initial radiotherapy and this can be successfully salvaged in most patients with further treatment. This mandates close follow-up to detect loco regional recurrence early.  相似文献   
16.
Silicon has long been the primary material of choice for microelectromechanical systems (MEMS) and integrated circuit (IC) applications. However, it is prone to degradation under severe conditions such as high humidity, high temperature, and corrosive environments. To overcome such extreme conditions and help silicon perform with stability and extended lifetimes, a protection layer is proposed. Mullite (3Al2O3·2SiO2) is a known environmental barrier coating (EBC) material and has been shown to be effective on other Si-based ceramic materials. In this work, dense, high-purity crystalline mullite coatings were deposited onto single-crystal silicon substrates via chemical vapor deposition (CVD). The microstructure, orientation preference, and adhesion of these coatings were investigated. Substrate integrity in relation to the substrate/coating interface by chemical etching and coating stability in a simulated severe environment under corrosive alkali salts were investigated.  相似文献   
17.
This paper addresses the issues relating to the communication channels in a physical simulator for flexible automation of a palletization task. The simulator used in our work involves an IBM-7545 robot, a personal computer and an Allen-Bradley Programmable Logic Controller (PLC). The communications relating to the Robot/PC interface and the PLC/PC interface are discussed.

The palletization station design requires that decisions on pallet pattern are made dynamically by a program running on the personal computer. The Robot/PC communication interface is necessary to transmit these decisions to the robot controller for execution. This communication is to be achieved using BASIC language and AML 4.1 as the software platforms.

The PLC has the task of controlling the transport of the boxes coming to the palletization station. The program for deciding the pallet pattern, running on the personal computer, needs real-time information on the counts of boxes of different sizes that are arriving for palletization. The PLC/PC interface serves to provide this information.  相似文献   

18.
Printed microstrip-fed antennas based on a slotted radiating patch are proposed herein. First, a basic rectangular antenna without any slots was designed, being suitable for wideband applications and showing impedance bandwidth of 2714 MHz for \(S_{11} < -10\) dB. Next, dual-band operation for worldwide interoperability for microwave access (WiMAX, from 3.11 to 3.97 GHz) and wireless local-area network (WLAN, 4.97–5.71 GHz) was obtained by including slots only on the left side of the basic design. Then, using a structure with slots on the right side of the radiating patch, WLAN operation was obtained in the frequency range of 2.865–2.096 GHz. The fourth antenna, with slots on both sides of the patch, was characterized and realized for biomedical applications at 2.45 GHz (\(S_{11} <-10\) dB). The proposed antennas can be realized with small ground plane size and total antenna area of only \(27.5 \times 21\,\hbox {mm}^{2}\). This reduction in total antenna area is achieved by using a truncated patch. All the simulations were carried out using Empire XCcel. The designs were characterized based on their radiation pattern, return loss, voltage standing wave ratio (VSWR), gain, and current distribution. The simulated and measured results show good compatibility.  相似文献   
19.
This paper discusses the design and development of a physical simulator for robotic palletization. The design is aimed at two objectives. One, to provide a test bed for studying issues relating to automation of palletization and second, to provide a teaching tool for some common elements of material handling automation. The major hardware components of the system are an IBM 7545 robot, a Personal Computer, an Allen-Bradley Programmable Logic Controller (PLC), Conveyors and a Bar Code Reader. The software components include the IBM AML 4.1 language, PLC Software and BASIC software for the BASIC Module of the PLC.  相似文献   
20.
Cytotoxic T lymphocytes (CTLs) are primary mediators of viral clearance, but high viral burden can result in deletion of antigen-specific CTLs. We previously reported a potential mechanism for this deletion: tumor necrosis factor (TNF)-alpha-mediated apoptosis resulting from stimulation with supraoptimal peptide-major histocompatibility complex. Here, we show that although death is mediated by TNF-alpha and its receptor (TNF-RII), surprisingly neither the antigen dose dependence of TNF-alpha production nor that of TNF-RII expression can account for the dose dependence of apoptosis. Rather, a previously unrecognized effect of supraoptimal antigen in markedly decreasing levels of the antiapoptotic protein Bc1-2 was discovered and is likely to account for the gain in susceptibility or competence to sustain the death signal through TNF-RII. This decrease requires a signal through the TCR, not just through TNF-RII. Although death mediated by TNF-RII is not as widely studied as that mediated by TNF-RI, we show here that it is also dependent on proteolytic cleavage by caspases and triggered by a brief initial encounter with antigen. These results suggest that determinant density can regulate the immune response by altering the sensitivity of CTLs to the apoptotic effects of TNF-alpha by decreasing Bc1-2 levels.  相似文献   
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