机组人员搭配协调性评价方法的研究

机组排班中机组成员搭配协调性关系到航班的飞行安全与服务质量。论文在分阶段机组排班思想研究的基础上,综合考虑机组人员技术、时间与性格等因素,按照搭配互补原则建立了机组协调性评价体系,给出了采用模糊优选动态规划思想将一个多阶段的问题转化为一个个单阶段问题,实现对机组协调性进行分析与评价的基本过程,为机组生成提供了形式化分析与解决方法。

基于MA技术的民航机组人员指派问题研究

为合理地指派民航飞行机组,根据机组所执行的勤务均衡理论,将机组指派分成机组生成和人员指派两部分完成。满足机组要求的飞行员生成一个飞行机组,同时将满足机型要求的机组安排到勤务中,通过多智能体(Multi-agent,MA)协同调度技术构成机组指派系统,实验证明并行调度技术在机组指派问题中能有效解决各个机组的勤务平衡问题,从而合理高效地进行机组指派。

Kinetic Modelling of Degradation of Organic Compounds in Soils

A set of equations is suggested to describe the kinetics of degradation of organic compounds applied tosoils and the kinetics of growth of the involved microorganisme:where x is the concentration of organic compound at time t, m is the number of forcroorganisms capableof degrading the organic compound at time t, while j, k, f and g are positive constaats. This model cansatisfactorily be used to explain the degradation curve of organic compounds and the growth curve of theinvolved microorganisms.

Viral exploitation of actin: force-generation and scaffolding functions in viral infection

As a fundamental component of the host cellular cytoskeleton, actin is routinely engaged by infecting viruses. Furthermore, viruses from diverse groups, and infecting diverse hosts, have convergently evolved an array of mechanisms for manipulating the actin cytoskeleton for efficacious infection. An ongoing chorus of research now indicates that the actin cytoskeleton is critical for viral replication at many stages of the viral life cycle, including binding, entry, nuclear localization, genomic transcription and reverse transcription, assembly, and egress/dissemination. Specifically, viruses subvert the force-generating and macromolecular scaffolding properties of the actin cytoskeleton to propel viral surfing, internalization, and migration within the cell. Additionally, viruses utilize the actin cytoskeleton to support and organize assembly sites, and eject budding virions for cell-to-cell transmission. It is the purpose of this review to provide an overview of current research, focusing on the various mechanisms and themes of virus-mediated actin modulation described therein.

Life Cycle Cost of Electricity Generation from Biomass Gasifier

India is having more than 500,000 villages of which about 85% have been electrified. But as per RGGVY （Rejiv Gandhi Grammen Vidyutikaran Yojana）, the rate of village electrification is much lower as household connectivity has been fairly low. The rest 15% villages and a larger proportion of households have to be electrified. Villages have been a major concern as cost of electrification is fairly high. The most favored alternative to any kind of users is generation of electricity from diesel generating sets and renewable sources of energy. But the capital cost of renewable energy equipments is fairly high. Gradually, there is a reduction in the prices of these systems due to availability of better technological options and they are becoming competitive to grid electricity. In this paper, an attempt has been made to calculate the cost of production of electricity from stand-alone, off-grid devices biomass gasifiers （both dual fuel and pure gas type） and compare with that of diesel generating sets by using the concept of LCC （life cycle costing） and Homer software. It is found that the cost of per unit electricity generation （kWh） has been always the lowest in comparison to diesel generating sets even if the price of biomass increases to some extent.

From cluster assembly to ultrathin nanocrystals and complex nanostructures

Ultrathin nanostructures have attracted much attention in recent years due to their predictable novel properties and various potential applications. The improvement in synthetic skills has led to many successful syntheses of nanostructures including zerodimensional (0D) nanoclusters, one-dimensional (1D) nanowires, two-dimensional (2D) nanosheets and other higher-level complex nanostructures, where cluster-assembly of primary nanocrystals is a common process. In this review, progress in ultrathin nanocrystals in the last decade and several important factors in the growth mechanisms are covered. By giving examples of cluster assembly from 1D to 3D nanostructures, the utility of cluster assembly in the synthesis of new materials has been demonstrated.

Responses of Soil Nematode Abundance and Diversity to Long-Term Crop Rotations in Tropical China

A field experiment was carried out from 2003 to 2013 in the Wanzhong Farm of the Hainan Island, China, to determine the effects of two long-term banana rotations on the abundance and trophic groups of soil nematode communities in the island. The experiment was set out as a randomized complete block design with three replications of three treatments： banana-pineapple rotation （AB）, banana-papaya rotation （BB） and banana monoculture （CK） in a conventional tillage system. Soil samples were taken at depths of 0-10, 10-20 and 20-30 cm, and nematodes were extracted by a modified cotton-wool filter method and identified to the genus level. Nematode ecological indices of Shannon-Weaver diversity （Ht）, dominance index （A）, maturity index （MI）, plant parasite index （PPI）, structure index （SI）, enrichment index （EI）, and channel index （CI） were calculated. A total of 28 nematode genera with relative abundance over 0.1% were identified, among which Tylenchus and Paratylenchus in the AB, Thonus in the BB, Tylenchus and Helicotylenchus in the CK were the dominant genera. The rotation soils favored bacterivores, fungivores and omnivores-predators with high colonizer-persister （c-p） values. Soil food web in the rotation systems was highly structured, mature and enriched as indicated by SI, MI and EI values, respectively. Higher abundance of bacterivores and lower values of CI suggested that the soil food web was dominated by a bacterial decomposition pathway in rotation soils. Nematode diversity was much higher after a decade of rotation. Soil depth had significant effects on the abundance of soil nematodes, but only on two nematode ecological indices （λ and MI）.

Impact of Land-Use Change on Soil Microbial Community Composition and Organic Carbon Content in the Dry Tropics

Restoration of forests poses a major challenge globally, particularly in the tropics, as the forests in these regions are more vulnerable to land-use change. We studied land-use change from natural forest(NF) to degraded forest(DF), and subsequently to either Jatropha curcas plantation(JP) or agroecosystem(AG), in the dry tropics of Uttar Pradesh, India, with respect to its impacts on soil microbial community composition as indicated by phospholipid fatty acid(PLFA) biomarkers and soil organic carbon(SOC) content. The trend of bacterial PLFAs across all land-use types was in the order: NF > JP > DF> AG. In NF, there was dominance of gram-negative bacterial(G^-) PLFAs over the corresponding gram-positive bacterial(G^+) PLFAs. The levels of G^- PLFAs in AG and JP differed significantly from those in DF, whereas those of G^+ PLFAs were relatively similar in these three land-use types. Fungal PLFAs,however, followed a different trend: NF > JP > DF = AG. Total PLFAs, fungal/bacterial(F/B) PLFA ratio, and SOC content followed trends similar to that of bacterial PLFAs. Across all land-use types, there were strong positive relationships between SOC content and G-, bacterial, fungal, and total microbial PLFAs and F/B PLFA ratio. Compared with bacterial PLFAs, fungal PLFAs appeared to be more responsive to land-use change. The F/B PLFA ratio, fungal PLFAs, and bacterial PLFAs explained 91%, 94%,and 73% of the variability in SOC content, respectively. The higher F/B PLFA ratio in JP favored more soil C storage, leading to faster ecosystem recovery compared to either AG or DF. The F/B PLFA ratio could be used as an early indicator of ecosystem recovery in response to disturbance, particularly in relation to land-use change.