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91.
A low-cost test solution for wireless phone RFICs   总被引:3,自引:0,他引:3  
This article describes an IBM approach for testing high-volume, complex RFICs at a fraction of the cost of the integrated circuit. This approach uses a personal computer, a fast benchtop dc parametric analyzer, and RF-to-analog circuits to test an RFIC during the manufacturing process. The described system and methodology are specifically designed for high-volume test, where test cost is extremely important; they are not recommended for lower-volume products (less than 1 million per month). This article describes the system architecture and discusses design, maintenance, and implementation considerations. The system is designed to reduce the cost of a complex RFIC manufacturing test to equal that of a discrete component, such as a resistor or capacitor. Given the relatively easy implementation and the drastic cost reduction associated with the test solution, this architecture establishes a new standard for the future of RF test. In fact, this architecture may result in the fastest RF tester currently available.  相似文献   
92.
Richard Moss 《通信世界》2008,(46):I0017-I0017
当重要的节日(如中国的春节和西方的圣诞节)到来之时,许多机构组织的大部分员工都休假了,业务通常在一段时间内完全停止,或最多只留下极少数员工来为其顾客提供服务。在欢庆的节假日里网络攻击者却不放假,因此对安全不能放松警惕。  相似文献   
93.
OBJECTIVE: To determine the efficacy of genetic testing of individuals presenting with features possibly indicative of von Hippel-Lindau (VHL) disease, regardless of other relevant family and clinical details. SETTING AND PARTICIPANTS: Between September 1994 and December 1997, 16 unrelated individuals were referred to Genetic Services of Western Australia by local clinicians and by similar genetic services in other States, for VHL gene mutation analysis because of clinical manifestations suggestive of the diagnosis. METHODS: The subjects were investigated by screening for mutations in the polymerase chain reaction products of the three VHL gene exons using single-stranded conformational polymorphism analysis (SSCP). If no mutations were detected the exons were sequenced, and if no variations were found DNA was examined by Southern analysis for germinal rearrangements. RESULTS: Mutations in the VHL gene were detected in eight of 16 individuals (50%), including 3 individuals with no family history suggestive of VHL disease. Five mutations were detected by SSCP, two by gene sequencing and one by Southern analysis. Each mutation occurred only in a single family and three had not been previously reported. CONCLUSION: Genetic screening of individuals presenting with clinical features suggestive of VHL facilitates confirmation of the diagnosis, accurate genetic counselling and surveillance of at-risk family members. The necessity for costly and time-consuming screening programs can be reduced and screening directed at those carrying the mutation. Our low stringency criteria are justified for screening for VHL mutations.  相似文献   
94.
BACKGROUND: The distinction between malignant mesothelioma (MM) and adenocarcinoma (ACA) in cytologic specimens frequently is difficult, often requiring immunocytochemistry to support the diagnosis. Recent reports have proposed the utilization of antibodies to mesothelial cell clone HBME-1 and thrombomodulin (TM), because they are immunoreactive in MM and less commonly reactive in ACA. Immunoreactivity for the monoclonal antibody CA 19-9 has been observed in many ACAs and reportedly is absent in MM. METHODS: In this study, immunostaining was performed on formalin fixed, paraffin embedded cell blocks from effusions or fine-needle aspirations using the avidin-biotin-peroxidase method. Thirty-eight MMs and 49 ACAs were tested using antibodies to CA 19-9, HBME-1, and TM. RESULTS: Anti-CA 19-9 stained only 1 of the 37 cases of MM tested (3%), but stained 24 of the 49 cases of ACA (49%). Anti-HBME-1 stained 34 of 38 cases of MM (89%), and 28 of 43 cases of ACA tested (65%). Anti-TM stained 24 of 36 cases of MM (67%), and 21 of 40 cases of ACA tested (53%). CONCLUSIONS: CA 19-9 has utility as part of an immunocytochemical panel for distinguishing ACA from MM, because a positive staining reaction would make the diagnosis of MM unlikely. Although HBME-1 and TM can identify MM positively, each frequently is detected in ACA, thus limiting the utility of these antibodies in cytologic specimens.  相似文献   
95.
OBJECTIVE: To determine whether Dexon mesh, closely applied to the kidney, provides purchase for sutures to permit bladder/parenchymal apposition on autotransplantation and that, if this line of apposition were some distance from but surrounding renal papillae, urothelium would proliferate to cover exposed parenchyma to form a widely patent lumen; this should facilitate removal of the whole of an upper tract collecting system, retaining renal parenchyma alone. MATERIALS AND METHODS: To test this possibility and explore the practicability of the concept, nine dogs underwent bilateral nephrectomy followed by unilateral autotransplantation: the other kidney was discarded. Because the canine renal pelvis is intrarenal, the ureter was stretched maximally before passing fine scissors into the renal hilum to transect the collecting system as close to the kidney as possible in six of the nine dogs. In the remaining three dogs, partial nephrectomy was performed with division of the calyceal necks under vision. Thinned bladder wall was sutured to Dexon mesh some distance from the collecting tubules; omentum was applied to the suture line. RESULTS: Three dogs were killed prematurely at < 2 weeks because of perioperative complications. Four were killed at 2, 4, 5 and 8 weeks and two at 12 months. Dexon mesh proved to be an effective anchoring fabric, providing close apposition of bladder wall and parenchyma. There was no adhesion of the kidney to peritoneal contents. Urothelial proliferation to cover exposed parenchyma occurred early and by 12 months, a thin stroma was interposed between parenchyma and epithelium. The kidney was preserved in all but one removed electively, this dog having both cystitis and pyelonephritis at 12 months. CONCLUSIONS: This study showed that autotransplantation of a kidney after removal of its collecting system and advancement of thinned bladder wall to renal parenchyma is practicable, with regenerated urothelium bridging the deficiency by covering exposed parenchyma, to create a widely patent lumen.  相似文献   
96.
Neurological complications arising from schistosomiasis are uncommon, and reports of Manson's schistosomiasis presenting as an intracerebral mass lesion are particularly rare. The authors describe the case of a 26-year-old man with a 3-month history of headaches and visual abnormalities. He had immigrated to Canada from Brazil 4 years previously. The patient's general physical and neurological examinations were unremarkable. Magnetic resonance (MR) imaging revealed an enhancing lesion with surrounding edema and mild mass effect in the right occipital lobe. A stereotactic brain biopsy demonstrated intraparenchymal granulomas surrounding Schistosoma masoni eggs. The patient's symptoms resolved following treatment with praziquantel and steroid medications; follow-up MR imaging yielded normal findings. This case demonstrates that neuroschistosomiasis should be considered when an individual presenting with an intracerebral mass has lived in a region in which this disease is endemic.  相似文献   
97.
We report a study of the acquisition of colour terms by Russian children which had two main aims: first, to test Berlin & Kay's (1969) theory of colour universals using acquisition order as a measure of basicness; and secondly, to see if the two BLUE terms of Russian are genuinely basic. Two hundred children aged from three to six-years-old were tested on three colour-tasks--colour term listing, colour term production and colour term comprehension. To a reasonable approximation, the order of colour term acquisition was in accord with Berlin & Kay's theory, but the data are also consistent with the weaker claim that primary terms tend to be learned before derived terms. On balance the data were consistent with Russian exceptionally, having an extra term for the BLUE region. But, the two BLUE terms--goluboj 'light blue' and sinij 'dark blue'--were confused more often than other pairs of terms even by the five- to six-year-old sample.  相似文献   
98.
99.
This paper presents a method of assessing the effective temperature essential for predicting the temperature acceleration of the wearout mechanisms (other than thermal fatigue) of electronic equipment. This is particularly important for equipment experiencing variable thermal conditions. The approach, based on weighting of thermal acceleration factors, leads to the Arrhenius average temperature T/sub eff/ given by (4). T/sub eff/ is related to wearout processes and allows one to compare predictions from the thermal design to results of accelerated testing. It has no relation to the maximum component temperature which influences functionality. The method is applicable to outside plant telecommunication equipment as well as in the automotive and aerospace industries. The effect of climate and design constraints on T/sub eff/ are discussed.  相似文献   
100.
The purpose of the present study is to examine the relation between quality of mother-child interaction in a lab and home setting, and quality of attachment of school-age children. A second objective of the study is to evaluate the associations between quality of mother-child interactions, attachment and maternal psychosocial measures (social support, depression, and parental stress). Security of attachment (Separation-Reunion procedure, Main & Cassidy, 1988) and the quality of mother-child interaction was evaluated for a sample of 38 children (mean age = 6 years). Mothers also completed self-report measures for depression, stress, and social support. Concurrent to the lab assessment, quality of mother-child interaction was also evaluated during a home visit. Results indicated a strong association between interactive patterns in both settings. Moreover, interactive patterns differed in terms of attachment classification with secure children showing the most harmonious patterns and disorganized/controlling children showing the most dysfunctional patterns. Maternal psychosocial measures were not related to child security of attachment, but mothers of insecure children reported marginally more stress related to the child. Maternal psychosocial adjustment was, in part, related to dyadic mother-child interaction in the home and lab setting. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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