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31.
We study bottleneck labeled optimization problems arising in the context of graph theory. This long-established model partitions
the set of edges into classes, each of which is identified by a unique color. The generic objective is to construct a subgraph
of prescribed structure (such as an s-t path, a spanning tree, or a perfect matching) while trying to minimize the maximum (or, alternatively, maximize the minimum)
number of edges picked from any given color. 相似文献
32.
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34.
Michael Fellows Jörg Flum Danny Hermelin Moritz Müller Frances Rosamond 《Theory of Computing Systems》2010,46(2):311-339
The classes of the W-hierarchy are the most important classes of intractable problems in parameterized complexity. These classes
were originally defined via the weighted satisfiability problem for Boolean circuits. Here, besides the Boolean connectives
we consider connectives such as majority, not-all-equal, and unique. For example, a gate labelled by the majority connective outputs true if more than half of its inputs are true. For any finite set
C\mathcal{C}
of connectives we construct the corresponding W(
C\mathcal{C}
)-hierarchy. We derive some general conditions which guarantee that the W-hierarchy and the W(
C\mathcal{C}
)-hierarchy coincide levelwise. If
C\mathcal{C}
only contains the majority connective then the first levels of the hierarchies coincide. We use this to show that a variant
of the parameterized vertex cover problem, the majority vertex cover problem, is W[1]-complete. 相似文献
35.
Danny Bradbury Author Vitae 《Computer Fraud & Security》2010,2010(10):10-13
36.
Photochemical transformation of terbutaline (pharmaceutical) in simulated natural waters: Degradation kinetics and mechanisms 总被引:1,自引:0,他引:1
Wenli Yang Sihem Ben Abdelmelek Zheng Zheng Taicheng An Danny Zhang Weihua Song 《Water research》2013
In this study, varied nature organic matter isolates were employed to investigate the indirect photo transformation of terbutaline, which is a major feed additive medicine to increase the proportion of lean meat in the livestock. In the indirect photolysis of terbutaline under solar simulated irradiation, 1O2 plays an important role among the •OH and 3DOM∗. The reaction rate constant of 1O2 was determined as (7.1 ± 0.3) × 106 M−1 s−1 at pH 7.0, while the reaction rate constant of •OH was (6.87 ± 0.43) × 109 M−1 s−1. The contribution of singlet oxygen to the indirect photolysis of terbutaline (19–44%) was higher than that of the hydroxyl radical (1–7%). The pseudo first order rate constants for the photodegradation of terbutaline increase with increasing pH, which indicates that pH mainly affects the reaction rate of the singlet oxygen with the phenolic part of the terbutaline. The Quinone was identified as the main photosensitized product through LC–MS/MS analysis. It is also proposed that the degradation pathway of terbutaline involves reaction between the phenolic part of terbutaline and singlet oxygen. This finding strongly suggests that singlet oxygen was important factor for the photodegradation of terbutaline in natural waters. 相似文献
37.
Sara Alcorn Amanda J. Walker Nishant Gandhi Amol Narang Aaron T. Wild Russell K. Hales Joseph M. Herman Danny Y. Song Theodore L. DeWeese Emmanuel S. Antonarakis Phuoc T. Tran 《International journal of molecular sciences》2013,14(7):14800-14832
As our understanding of the molecular pathways driving tumorigenesis improves and more druggable targets are identified, we have witnessed a concomitant increase in the development and production of novel molecularly targeted agents. Radiotherapy is commonly used in the treatment of various malignancies with a prominent role in the care of prostate cancer patients, and efforts to improve the therapeutic ratio of radiation by technologic and pharmacologic means have led to important advances in cancer care. One promising approach is to combine molecularly targeted systemic agents with radiotherapy to improve tumor response rates and likelihood of durable control. This review first explores the limitations of preclinical studies as well as barriers to successful implementation of clinical trials with radiosensitizers. Special considerations related to and recommendations for the design of preclinical studies and clinical trials involving molecularly targeted agents combined with radiotherapy are provided. We then apply these concepts by reviewing a representative set of targeted therapies that show promise as radiosensitizers in the treatment of prostate cancer. 相似文献
38.
39.
Agents and the Semantic Web 总被引:4,自引:0,他引:4
Many challenges of bringing communicating multi-agent systems to the World Wide Web require ontologies. The integration of agent technology and ontologies could significantly affect the use of Web services and the ability to extend programs to perform tasks for users more efficiently and with less human intervention. 相似文献
40.
Junji Kondoh Ahmed Shafiu Nick Jenkins Danny Pudjianto Goran Strbac 《Electrical Engineering in Japan》2011,176(3):19-28
A direct load management scheme with two‐way communication, with consideration of end‐user comfort, is proposed. First, the control algorithm is developed and the data required to be transmitted between system operator and controllable loads are identified. Then, the actions of controllable air conditioners and the power adjustment of dispersed generators to eliminate overloads in a substation transformer are simulated. The results indicate that the proposed load management technique performs effectively to reduce overloads on the transformer while maintaining energy consumption in each load, and the performance is improved by coordination with the output of dispersed generators. © 2011 Wiley Periodicals, Inc. Electr Eng Jpn, 176(3): 19–28, 2011; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.21139 相似文献