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11.
《钢铁冶炼》2013,40(3):187-194
Abstract

Controlling the annealing cycle in a hot dip galvanising line (HDGL) is vital if each coil treated is to be properly galvanised and the steel is to have the right properties. Current HDGL furnace control models usually take into account the dimensions of the coil to be dipped and, in some cases, the type of steel. This paper presents a new model for monitoring furnace temperature settings, which considers not just the coil dimensions but also the chemical composition of the steel. This enables the model to be adjusted more suitably to each type of steel to be dipped, so that the HDGL annealing cycle is optimised and rendered more efficient in dealing with new products. The ultimate aim is to find a model that is equally efficient for new types of steel coil that have not been processed before and whose dimensions and chemical compositions are different from coils processed previously. To find the best model, this paper compares various new and classical algorithms for developing a precise and efficient prediction model capable of determining the three temperature settings for heating on an HDGL located in Avilés (Spain) on the basis of the physical and chemical characteristics of the coils to be processed and the preset process conditions.  相似文献   
12.
刘谦雷  杨绿溪 《信号处理》2005,21(4):331-334
单载波频域均衡(SC-FDE)是多输入多输出(MIMO)无线通信中克服多径衰落的一种重要技术。本文基于V-BLAST信号检测的原理,对MIMO-SC-FDE系统提出了以块为单位进行分层检测的块BLAST算法。在该算法中,系统按一定的准则确定对各路发送信号进行频域均衡和检测的顺序,较先检测出的信号被变换到频域作为干扰从接收信号中去除,使得对以后各路信号进行频域均衡和检测的信干噪比得以提高,从而大大改善了MIMO-SC-FDE系统的误码性能。仿真实验结果显示,块BLAST算法取得了大大优越于MIMO-SC-FDE常规检测算法的误码性能。  相似文献   
13.
A High Data Rate (HDR) system has been proposed for providing downlink wireless packet service by using a channel-aware scheduling algorithm to transmit to users in a time-division multiplexed manner. In this paper, we propose using multiple antennas at the transmitter and/or at the receiver to improve performance of an HDR system. We consider the design tradeoffs between scheduling and multi-antenna transmission/detection strategies and investigate the average Shannon capacity throughput as a function of the number of antennas assuming ideal channel estimates and rate feedback. The highest capacities are achieved using multiple antennas at both the transmitter and receiver. For such systems, the best performance is achieved using a multi-input multi-output capacity-achieving transmission scheme such as BLAST (Bell Labs Layered Space-Time) in which the transmitted signal is coded in space and time, and the receive antennas are used to resolve the spatial interference. In the second part of the paper, we discuss practical transmitter and receiver architectures using BLAST for approaching the theoretical gains promised by the capacity analysis. Because the terminal receivers will be portable devices with limited computational and battery power, we perform a computational complexity analysis of the receiver and make high-level assessments on its feasibility. We conclude that the overall computational requirements are within the reach of current hardware technology.  相似文献   
14.
The present study is focused on bio hydrogen (H2) and bioplastic (i.e., poly-β-hydroxybutyrate; PHB) productions utilizing various wastes under dark fermentation, photo fermentation and subsequent dark-photo fermentation. Potential bio H2 and PHB producing microbes were enriched and isolated. The effects of substrate (rice husk hydrolysate, rice straw hydrolysate, dairy industry wastewater, and rice mill wastewater) concentration (10–100%) and pH (5.5–8.0) were examined in the batch mode under the dark and photo fermentation conditions. Using 100% rice straw hydrolysate at pH 7, the maximum bio H2 (1.53 ± 0.04 mol H2/mol glucose) and PHB (9.8 ± 0.14 g/L) were produced under dark fermentation condition by Bacillus cereus. In the subsequent dark-photo fermentation, the highest amounts of bio H2 and PHB were recorded utilizing 100% rice straw hydrolysate (1.82 ± 0.01 mol H2/mol glucose and 19.15 ± 0.25 g/L PHB) at a pH of 7.0 using Bacillus cereus (KR809374) and Rhodopseudomonas rutila. The subsequent dark-photo fermentative bio H2 and PHB productions obtained using renewable biomass (i.e., rice husk hydrolysate and rice straw hydrolysate) can be considered with respect to the sustainable management of global energy sources and environmental issues.  相似文献   
15.
The COVID-19 coronavirus is a new strain of coronavirus that had not been previously detected in humans. As its severe pathogenicity is concerned, it is important to study it thoroughly to aid in the discovery of a cure. In this study, the microRNAs (miRNAs) of COVID-19 were annotated to provide a powerful tool for the study of this novel coronavirus. We obtained 16 novel coronavirus genome sequences and the mature sequences of all viruses in the microRNA database (miRbase), and then used the miRNA mature sequences of the virus to perform the Basic Local Alignment Search Tool (BLAST) analysis in the coronavirus genome, extending the matched regions of approximately 20 bp to two segments by 200 bp. Six sequences were obtained after deleting redundant sequences. Then, the hairpin structures of the mature miRNAs were determined using RNAfold. The mature sequence on one hairpin arm was selected into a total of 4 sequences, and finally the relevant miRNA precursor prediction tools were used to verify whether the selected sequences are miRNA precursor sequences of the novel coronavirus. The miRNAs of the novel coronavirus were annotated by our newly developed method, which will lay the foundation for further study of this virus.  相似文献   
16.
BLASTZ is a sequence alignment tool designed mainly for aligning neutrally evolved bio-sequences and has been the choice for aligning noncoding sequences. However, its running time is impractical for high throughput alignment of long sequences, for example, for the alignment of human and mouse genomes. In order to improve the performance and efficiency for alignment at genome scale, BLASTZ was implemented using the GLOBUS toolkit on a computing grid. A dynamic load balancing technique was introduced to achieve enhanced performance on a grid which consists of sources of heterogeneous characteristics, such as resources of different computational powers. The robustness of the implementation to disturbances due to other processes on the grid is demonstrated.
Jagath C. Rajapakse (Corresponding author)Email:
  相似文献   
17.
The process of DNA sequence matching and database search is one of the major problems of the bioinformatics community. Major scientific efforts to address this problem have provided algorithms and software tools for molecular biologists since the early 1970s. At the algorithmic and software level BLAST is by far the most popular tool. It has been developed and continues to be maintained and distributed by the NCBI organization. The BLAST algorithm and software is computationally very intensive and as a result several computer vendors use it as a benchmark. On the other hand no systematic approach for hardware speedup of BLAST and its variants for different query and database size has been reported to date. In this paper we present our architecture that implements the BLAST algorithm for all of its major versions, and for any size of database and query. The system has been fully designed and partially implemented with reconfigurable logic. It consists of software and hardware parts and achieves a speedup of several times up to thousands of times vs general purpose computers.
Apostolos DollasEmail:
  相似文献   
18.
Protein secondary structures are important in many biological processes and applications. Due to advances in sequencing methods, there are many proteins sequenced, but fewer proteins with secondary structures defined by laboratory methods. With the development of computer technology, computational methods have (started to) become the most important methodologies for predicting secondary structures. We evaluated two different approaches to this problem—driven by the recent results obtained by computational methods in this task—(i) template-free classifiers, based on machine learning techniques; and (ii) template-based classifiers, based on searching tools. Both approaches are formed by different sub-classifiers—six for template-free and two for template-based, each with a specific view of the protein. Our results show that these ensembles improve the results of each approach individually.  相似文献   
19.
MIMO-DFE(Multiple-Input-Multiple-Output Decision Feedback Equalizer) based receiver architectures are researched recently to detect signals in BLAST(Bell laboratories LAyered Space-Time) over frequency-selective channels. Due to their recursive structure, these receivers may suffer from error propagation which results in an overall mean square error degradation. An MIMO-DFE based BLAST receiver with limited error propagation to combat frequencyselective channel is proposed, which employs both norm constraint on feedback filter taps and soft decision device. Simulation results show that the proposed receiver outperforms conventional ones in various frequency selective channels.  相似文献   
20.
Over the past few years, research and development in bioinformatics (e.g. genomic sequence alignment) has grown with each passing day fueling continuing demands for vast computing power to support better performance. This trend usually requires solutions involving parallel computing techniques because cluster computing technology reduces execution times and increases genomic sequence alignment efficiency. One example, mpiBLAST is a parallel version of NCBI BLAST that combines NCBI BLAST with message passing interface (MPI) standards. However, as most laboratories cannot build up powerful cluster computing environments, Grid computing framework concepts have been designed to meet the need. Grid computing environments coordinate the resources of distributed virtual organizations and satisfy the various computational demands of bioinformatics applications. In this paper, we report on designing and implementing a BioGrid framework, called G‐BLAST, that performs genomic sequence alignments using Grid computing environments and accessible mpiBLAST applications. G‐BLAST is also suitable for cluster computing environments with a server node and several client nodes. G‐BLAST is able to select the most appropriate work nodes, dynamically fragment genomic databases, and self‐adjust according to performance data. To enhance G‐BLAST capability and usability, we also employ a WSRF Grid Service Portal and a Grid Service GUI desk application for general users to submit jobs and host administrators to maintain work nodes. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
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