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991.
C Rübe 《Canadian Metallurgical Quarterly》1997,86(42):1654-1659
Radiotherapy is an important modality in the postoperative and primary treatment of non-small cell lung cancer. Treatment results are rather unsatisfactory and have not basically changed in the past 15-20 years. In the nearer past, new treatment strategies were developed, which may contribute to a substantial improvement of the poor prognosis. On one hand, novel fractionation schedules using hyperfractionated accelerated radiation show promising results by improving local control. On the other hand, the main interest of many groups is focussed on a combined modality treatment using radiotherapy plus neoadjuvant or concurrent chemotherapy and surgery. There are numerous reports in the literature which document an advantage in survival of combined modalities over radiotherapy alone with improvements concerning local control as well as distant spread. The bases of the encouraging results is the use of a simultaneous or sequential combination of cisplatin-containing chemotherapy and high dose radiation. The following article reviews the relevant data from the literature with main emphasis on radiochemotherapy regimens. 相似文献
992.
The authors study the performance of a multichannel modulation method for asymmetric digital subscriber lines (ADSLs) and very high-speed digital subscriber lines (VHDSLs). In the ADSL case, over all unloaded North American subscriber lines in the test set, a unidirectional 1.536 Mb/s data rate service from the end office to the customer premises is possible on a single twisted pair at an error rate of 10-7 with at least a 6 dB margin used coded multichannel modulation with sufficient transmit power. In the VHDSL case, data rates in excess of 100 Mb/s can be transmitted reliably, at an error rate of 10-7, using uncoded multichannel modulation on a single twisted pair over a distance ⩽150 ft with a sufficiently high sampling rate (≈24 MHz) and transmit power. It is shown that a cost-effective multichannel transceiver design suggested for high-speed digital subscriber line (HDSL) service will also work well for ADSL and VHDSL services with only minimal modifications 相似文献
993.
994.
Numerous power utilities have installed advanced distributed temperature sensing (DTS) systems to measure the temperature of underground cables. This paper presents a general procedure for real-time assessment of underground cable ratings based on DTS. After the identification and location of hot spots on a cable, the cable installation data, load, and DTS-recorded temperature over a period of time are used to estimate soil thermal parameters and assess cable ratings under normal and overloading conditions. In order to accurately estimate soil thermal parameters, a combined technique of the finite-element method and gradient-based optimization is used. The technique was validated in the laboratory and applied to a rating assessment of a 230-kV/500-MVA cable circuit. The assessed continuous and emergency ratings are helpful in improving the operation of this circuit. 相似文献
995.
This paper presents a computer model for the probabilistic representation of wind farms generation for reliability studies, which can provide an annual estimation of energy production and calculate several performance indexes. The model combines the stochastic characteristics of wind speed with the operational information of the turbines, such as the failure and repair rates, representing the wind farm by a Markov process. The simulations are made with real time series of wind speed of several Brazilian regions and actual turbine models. The influence of some wind farm and installation site characteristics on the results are evaluated, such as the wind speed statistical clustering technique, the number and type of the turbines, and the failure and repair rates. The results obtained reproduce successfully the behavior of the components considered in the model 相似文献
996.
Jagath C Rajapakse Choong Leong Tan Xuebin Zheng Susanta Mukhopadhyay Kanyan Yang 《IEEE engineering in medicine and biology magazine》2006,25(2):102-111
Covariance-based methods of exploration of functional connectivity of the brain from functional magnetic resonance imaging (fMRI) experiments, such as principal component analysis (PCA) and structural equation modeling (SEM), require a priori knowledge such as an anatomical model to infer functional connectivity. In this research, a hybrid method, combining independent component analysis (ICA) and SEM, which is capable of deriving functional connectivity in an exploratory manner without the need of a prior model is introduced. The spatial ICA (SICA) derives independent neural systems or sources involved in task-related brain activation, while an automated method based on the SEM finds the structure of the connectivity among the elements in independent neural systems. Unlike second-order approaches used in earlier studies, the task-related neural systems derived from the ICA provide brain connectivity in the complete statistical sense. The use and efficacy of this approach is illustrated on two fMRI datasets obtained from a visual task and a language reading task. 相似文献
997.
POINT: AOP Will See Widespread Adoption Adrian Colyer, Rob Harrop, Rod Johnson, and Alexandre Vasseur AOP offers both the short--and long-term return on investment needed to ensure its widespread adoption. COUNTERPOINT: AOP Has Yet to Prove Its Value Danio Beuche and Cédric Beust Where is the proof that nonhierarchical modularization into aspects makes systems development cheaper or better? 相似文献
998.
Cinquemani P.L. Kuchta F.L. Hayes H.L. III Chavarria G.E. Lindler C.E. Jr. 《Power Delivery, IEEE Transactions on》2005,20(1):4-10
High-stress design 35-kV ethylene propylene rubber (EPR)-insulated cables with 1.14-mm (45-mil) wall reduction have been in service for more than ten years. In the mid 1990s, an extensive cable testing program was initiated to demonstrate that high-stress designs up to 4 kV/mm (101.6 V/mil) exhibit a significant electrical and mechanical safety margin to operate on typical utility network systems. Investigations were also undertaken to demonstrate the suitability of accessories for high-stress designs. This paper will present the results of six-year, long-term wet electrical testing conducted to demonstrate that with proper design, the aging performance of standard wall and high-stress design cables provide satisfactory results and suitable performance for the intended application. Additionally, utility field experience is presented on 35- and 15-kV cables operating at high stress. The experience for these 15-kV medium-voltage EPR cable designs employ the highest recommended stress for cables of this class, as well as taking into account the complete system performance. 相似文献
999.
G Langergraber C Prandtstetten A Pressl R Rohrhofer R Haberl 《Water science and technology》2007,56(3):75-84
Using subsurface vertical flow constructed wetlands (SSVFCWs) with intermittent loading it is possible to fulfil the stringent Austrian effluent standards regarding nitrification. For small plants (less than 500 persons) standards for ammonia nitrogen concentration have to be met at water temperatures higher than 12 degrees C, effluent concentrations and treatment efficiencies for organic matter have to be met the whole year around. According to the Austrian design standards the required surface area for SSVFCWs treating wastewater was 5 m2 per person. Within the first part of an Austrian research project the goal was to optimise, i.e. minimise the surface area requirement of vertical flow beds. Therefore, three SSVFCWs with a surface area of 20 m2 each have been operated in parallel. The organic loads applied were 20, 27 and 40 g COD/m2/d, which corresponds to a specific surface area requirement of 4, 3 and 2 m2 per PE, respectively. The paper compares the effluent concentrations and elimination efficiencies of the three parallel operated beds. It could be shown that a specific area demand of 4 m2 per person is suitable to be included in the revision of the Austrian design standard. Additionally it could be shown that during the warmer seasons (May-October) when the temperature of the effluent is higher than 12 degrees C the specific surface area might be further reduced; even 2 m2 per person has been proven to be adequate. 相似文献
1000.
Although the main function of reservoirs in agriculture is to allow the storage and temporal shifting of large volumes of waters, further benefits emerge from their application in wastewater reuse systems. In fact, as observed in several other studies carried out on such complex natural systems, the storage period, under proper conditions, can lead to a significant improvement of the water quality for irrigation thanks to concurrent physical, chemical and biological processes. In order to investigate the reservoir dynamics, an experimental research was carried out in a farm reservoir (volume of 11,000 m3, maximum depth of 6.3 m and mean depth of about 5 m), receiving treated wastewater and subject to scheduled highly variable input to volume ratios, in order to observe the broadest range of behaviour responses. Specifically, over a monitoring period lasted 4 months, the reservoir was operated as a standard batch reactor in the first and third phases and as a continuous flow reactor in the second one. Based on correlation analysis between the chemical, physical and biological water parameters and operational ones, a new operative index is proposed which integrates the morphological characteristics of the tank and the management ones, and shows a significant correlation with the qualitative characteristics of the stored water. 相似文献