Pengtao Zhang

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China’s grain-for-green policy of converting steep cultivated land to forest and grassland is one of the most important initiatives to develop its western inland regions. Using a multi-objective programming model, this study assessed the impacts of this policy in the upper reaches of the Yangtze River and the upper and middle reaches of the Yellow River. In(More)
Promoting the degradation of Hsp90 client proteins by inhibiting Hsp90, an important protein chaperone, has been shown to be a promising new anticancer strategy. In this study, we show that an oxazoline analogue of apratoxin A (oz-apraA), a cyclodepsipeptide isolated from a marine cyanobacterium, promotes the degradation of Hsp90 clients through(More)
As viruses become more complex, existing antivirus methods are inefficient to detect various forms of viruses, especially new variants and unknown viruses. Inspired by immune system, a hierarchical artificial immune system (AIS) model, which is based on matching in three layers, is proposed to detect a variety of forms of viruses. In the bottom layer, a(More)
Along with the evolution of computer viruses, the number of file samples that need to be analyzed has constantly increased. An automatic and robust tool is needed to classify the file samples quickly and efficiently. Inspired by the human immune system, we developed a local concentration based virus detection method, which connects a certain number of(More)
A malware detection model based on a negative selection algorithm with penalty factor (NSAPF) is proposed in this paper. This model extracts a malware instruction library (MIL), containing instructions that tend to appear in malware, through deep instruction analysis with respect to instruction frequency and file frequency. From the MIL, the proposed model(More)
This paper proposes an immune concentration based virus detection approach which utilizes a two-element concentration vector to construct the feature. In this approach, ‘self’ and ‘nonself’ concentrations are extracted through ‘self’ and ‘nonself’ detector libraries, respectively, to form a vector with two elements of concentrations for characterizing the(More)
This paper proposes a novel feature construction approach based on term space partition (TSP) aiming to establish a mechanism to make terms play more sufficient and rational roles in email categorization. Dominant terms and general terms are separated by performing a vertical partition of the original term space with respect to feature selection metrics,(More)
The stability control problem of desuperheating water system of supercritical power generation unit once-through boiler is studied in this paper. The cascade PID control strategy is adopted and applied to desuperheating water control system. Because the valve opening of the desuperheating water regulator can be adjusted in real time with the unit load(More)
This paper proposes a new feature-goodness criterion named class-wise information gain (CIG). The CIG is able to measure the goodness of a feature for recognizing a specific class, and further helps to select the features with the highest information content for a specific class. In order to confirm the effectiveness of the CIG, a CIG-based malware(More)
Cellular protein synthesis is initiated with methionine in eukaryotes with few exceptions. Methionine aminopeptidases (MetAPs) which catalyze the process of N-terminal methionine excision are essential for all organisms. In mammals, type 2 MetAP (MetAP2) is known to be important for angiogenesis, while type 1 MetAP (MetAP1) has been shown to play a pivotal(More)