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1.
台北101层国际金融中心之结构施工技术与其设计考量概述 总被引:1,自引:0,他引:1
本文旨在简要说明目前正在施工中之超高层大楼—台北国际金融中心之结构系统、钢结构工程、钢筋混凝土工程基础与深开挖工程等特殊施工技术,并佐以相关之设计考量与施工规划概要,以供工程界做参考。 相似文献
2.
ZnO thin film was deposited on various metal electrodes by reactive sputtering, and c-axis preferred orientation of the film has been studied. ZnO, which has high piezoelectricity, is promising for oscillators or filter devices such as surface acoustic wave (SAW) device, gas sensor, and film bulk acoustic resonator (FBAR). But, for the application of ZnO film for these devices, the film should be grown with c-axis normal to the electrode. In this study, Pt, Al, and Au were deposited on Si wafer, and the surface roughness and crystal structure of the ZnO film on the electrode were investigated using AFM, scanning electron microscopy (SEM), and X-ray diffraction (XRD). Columnar structures of ZnO films were grown with c-axis normal to all electrodes, and among them Pt electrode showed the highest preferred orientation of ZnO film. 相似文献
3.
Cancer invasion and metastasis are associated with matrix degradation. We describe a novel in vivo model of invasion by squamous epithelial neoplastic cells derived from transgenic mice grown on acellular human dermis. Human dermis was subjected to multiple freeze-thaw cycles to render it acellular, maintaining the basement membrane of the former dermal-epidermal junction. Cells representing discrete stages of a multistep transgenic mouse model of epidermal carcinogenesis (neonatal transgenic keratinocytes, moderately/poorly differentiated squamous cell carcinoma, and lymph node metastasis) were seeded onto the basement membrane surface, grown in culture for 4 days, grafted in a subpannicular pocket of athymic mice, and harvested after 3 weeks. Histological analysis demonstrated that neonatal transgenic keratinocytes did not degrade the basement membrane or invade the underlying dermis. In contrast, malignant cells derived from both a moderately differentiated squamous carcinoma and a lymph node metastasis were highly invasive. Immunohistochemical analysis revealed collagenase only in nests of invading malignant cells in contact with the dermal matrix, but not in the tumor mass remaining above the basement membrane, suggesting that this proteinase may be required for stromal invasion. This novel model recapitulates the events seen in malignant invasion: transgenic keratinocytes are unable to penetrate the dermis while cells from a moderately differentiated carcinoma and from lymph node metastasis consistently invade. 相似文献
4.
W.R. Jong T.H. Kuo S.W. Ho H.H. Chiu S.H. Peng 《International Communications in Heat and Mass Transfer》2007
Capillary phenomena was studied and discussed by the scholars about 200 years ago, but the progress was slow due to the limited equipment and manufacture precision of the microchannel. In recent years, because of the rapid development of MEMS and micromachining, many applications of the capillary flow is widely developing in some modern processes, such as underfilling of flip chip, flow in microfluidic chip or biochip, and a variety of other fields. 相似文献
5.
Jong Min Kim Donghee Lee Sang Lyul Min Chong Sang Kim 《Information Processing Letters》2003,85(2):93-97
A new dynamic buffer allocation strategy based on the notion of marginal gains is presented for the buffer cache that is used by the operating system to store frequently accessed disk blocks in main memory, and the performance of the proposed strategy is compared with those of previous allocation strategies. In the proposed strategy, marginal gain values are predicted by exploiting functions that approximate the expected number of buffer hits per unit time. Experimental results from both trace-driven simulation and an actual implementation in the FreeBSD operating system show that the proposed strategy accurately predicts the marginal gain values for various workloads resulting in significantly improved buffer hit ratios. 相似文献
6.
Sang-Hoon Lee Dae Hwan Kim Kyung Rok Kim Jong Duk Lee Byung-Gook Park Young-Jin Gu Gi-Young Yang Jeong-Taek Kong 《Nanotechnology, IEEE Transactions on》2002,1(4):226-232
A practical model for a single-electron transistor (SET) was developed based on the physical phenomena in realistic Si SETs, and implemented into a conventional circuit simulator. In the proposed model, the SET current calculated by the analytic model is combined with the parasitic MOSFET characteristics, which have been observed in many recently reported SETs formed on Si nanostructures. The SPICE simulation results were compared with the measured characteristics of the Si SETs. In terms of the bias, temperature, and size dependence of the realistic SET characteristics, an extensive comparison leads to good agreement within a reasonable level of accuracy. This result is noticeable in that a single set of model parameters was used, while considering divergent physical phenomena such as the parasitic MOSFET, the Coulomb oscillation phase shift, and the tunneling resistance modulated by the gate bias. When compared to the measured data, the accuracy of the voltage transfer characteristics of a single-electron inverter obtained from the SPICE simulation was within 15%. This new SPICE model can be applied to estimating the realistic performance of a CMOS/SET hybrid circuit or various SET logic architectures. 相似文献
7.
Recurrent hyperparathyroidism due to parathyroid autografts: incidence, presentation, and management
Recurrent hyperparathyroidism (HPT) occurs in a small percentage of patients undergoing parathyroidectomy for primary HPT and is usually due to inadequate excision of hyperfunctioning parathyroid tissue in the neck, a missed ectopic and hyperplastic parathyroid, or, less commonly, parathyroid carcinoma and parathyroid autografts. In order to determine the incidence, clinical characteristics, and outcome of patients with recurrent HPT due to parathyroid autografts, we reviewed our experience with 604 consecutive patients operated on for primary HPT between 1965 and 1989. One hundred of these patients received parathyroid autografts consisting of portions of one or more parathyroid glands. Three patients with autografts, placed in the sternocleidomastoid muscle, developed recurrent HPT due to their autografts for an incidence of 3 per cent. Recurrent disease was diagnosed between 62 and 113 months with an average of 89 months. The autotransplants in all three of these patients were from hyperplastic or adenomatous parathyroid tissue. Two patients had a history of neck irradiation. Preoperative thallium scans accurately localized the hyperfunctioning parathyroid tissue in all three patients. At operation, the hyperfunctioning autografts had grown into a discrete mass with a single vascular pedicle and were resected. Histologic examination disclosed either hyperplastic or adenomatous tissue, and corresponded to the histology and location of the original tissue transplanted in each case. Follow-up ranges from 12 to 67 months, with an average of 48 months. All patients remain cured and none require oral calcium supplementation. We conclude that graft-dependent recurrent HPT is due to the autotransplantation of hyperplastic or adenomatous parathyroid tissue and that thallium scanning is instrumental for diagnosis and localization.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
8.
EM de Jong BA Seegers MK Gulinck JB Boezeman PC van de Kerkhof 《Canadian Metallurgical Quarterly》1996,193(4):300-303
We present the first case of esophagogastric devascularization and esophagogastric transection using a stapler through laparoscopic surgery. The procedure was performed in a 71-year-old diabetic woman with alcoholic liver cirrhosis (Child-Pugh B class), portal hypertension, bleeding grade III esophageal varices, and a previous bleeding episode. The surgical technique was carried out without problems, and the patient had an excellent postoperative condition. Esophagogastric devascularization with esophageal transection using a stapler through laparoscopic surgery is a feasible technique that accomplishes the same and all objectives of the open procedure. Operative time in both methods is the same, whereas surgical trauma, inmunologic depletion, amount of transfused blood, pain, use of analgesics, and hospital stay are reduced in the laparoscopic technique. 相似文献
9.
FH Wapstra H Van Goor G Navis PE De Jong D De Zeeuw 《Canadian Metallurgical Quarterly》1996,90(5):393-401
1. The mechanism of renal protection by angiotensin-converting enzyme inhibition is still the subject of debate. Inhibition of proteinuria might play a role. If so, a good antiproteinuric response to angiotensin-converting enzyme inhibition should predict subsequent protection against renal structural damage. This hypothesis has not been tested in models where treatment is started after the renal disease is well established, i.e. models that mimic the clinical situation. 2. We therefore investigated this hypothesis in 96 male Wistar rats with established adriamycin nephrosis. Reduction of proteinuria was achieved by lisinopril (0, 2, 5 and 10 mg day-1 kg-1) on two different sodium diets (0.3% and 0.05% NaCl). Therapy started 6 weeks after adriamycin (at stable proteinuria) and was continued for 6 weeks. 3. Lisinopril reduced blood pressure by 32 +/- 4% and proteinuria by an average of 72 +/- 7%, with stabilization after 2 weeks. Considerable interindividual differences in antiproteinuric response was found. Glomerulosclerosis score was reduced by 15 +/- 5%. All the effects of angiotensin-converting enzyme inhibitors were enhanced by sodium depletion, but sodium depletion in itself did not affect blood pressure (124 +/- 4 mmHg), proteinuria (664 +/- 68 mg/day) or glomerulosclerosis score (30 +/- 5%). Interestingly, the more proteinuria was reduced initially in an individual rat, the less sclerosis was found in the long term in that rat. 4. In conclusion, angiotensin-converting enzyme inhibition lowers proteinuria and prevents glomerulosclerosis in established adriamycin nephrosis. These effects are enhanced by sodium depletion. The individual short-term antiproteinuric effect predicts the protection against ultimate glomerular damage. This is consistent with the hypothesis that reduction of proteinuria is a mechanism by which angiotensin-converting enzyme inhibitors exert renoprotection. 相似文献
10.
Sung Ho Jeong Joon Jeong Yi Jong Keun Kim Man Yeong Ha 《Journal of Mechanical Science and Technology》1991,5(1):16-21
A computer program to calculate the strip temperature heated in the continuous annealing furnace was developed, using the
zone method for radiative heat transfer analysis with the measured gas temperature in the furnace. Using theF
E Operator, the present study considered the effects of soot and transient species, in addition to the H2O−CO2 gas mixture on the gas radiative heat transfer. The predicted strip temperature distribution forF
E=1.05 represented well the measured data. The maximum difference in the heat flux transfered to the strip from the combustion
gas forF
E=1.0 (without soot and transient species gas radiation) and 1.05 (with soot and transient species gas radiation) was about
15%. The present study also investigated the effects of line speed and thickness variations on the strip temperature, establishing
the bases for the on-line computer model. 相似文献