Vegetation effects on mean daily maximum and minimum surface air temperatures over China

Changes in the daily maximum (Tmax) and minimum (Tmin) surface air temperatures and the associated temperature extremes have severe consequences on human society and the natural environment. In this study, we assess vegetation effects on mean Tmax and Tmin over China by computing a vegetation feedback parameter using the satellite-sensed Normalized Difference Vegetation Index (NDVI) and observed temperatures for the period 1982–2002. In all seasons, vegetation exerts a much stronger forcing on Tmax than on Tmin, and thus has a substantial effect on the diurnal temperature range (DTR) over China. Significant positive feedbacks on Tmax and the DTR occupy many areas of China with the feedback parameters exceeding 1°C (0.1 NDVI)–1, while significant negative effects only appear over the summertime climatic and ecological transition zone of northern China and some other isolated areas. Also, the vegetation feedbacks are found to vary with season. In areas where significant feedbacks occur, vegetation contributes to typically 10%–30% of the total variances in Tmax, Tmin, and the DTR. These findings suggest that vegetation memory offers the potential for improving monthly-to-seasonal forecasting of Tmax and Tmin, and the associated temperature extremes over China. Meanwhile, the limitations and uncertainties of the study should be recognized.     

Removable ears of 1-extendable graphs

<正> Carvalho,Lucchesi and Murty proved that any 1-extendable graph G different from K_2and C_(2n)has at least Δ(G)edge-disjoint removable ears,and any brick G distinct from K_4 and■hasat least Δ(G)-2 removable edges,where Δ(G)denotes the maximum degree of G.In this paper,weimprove the lower bounds for numbers of removable ears and removable edges of 1-extendable graphs.It is proved that any 1-extendable graph G different from K_2 and C_(2n)has at least χ′(G)edge-disjointremovable ears,and any brick G distinct from K_4 and■has at least χ′(G)-2 removable edges,whereχ′(G)denotes the edge-chromatic number of G.     

Exploring an Explicit Use of the Concept of Sustainability in Transport Planning

The aim of this paper is to explore an explicit use of the concept of sustainability within transport planning. This paper analyses the concept of sustainability based on a practical approach for a sustainable development of Nordhavn, an area of Copenhagen, exemplifying a complex planning problem. An exploration of the application of the concept of sustainability is carried out using elements of Soft Systems Methodology (SSM). This approach indicates a need to separate the use of sustainability considerations regarding the transport planning ‘process’ from the transport planning ‘results’. The two approaches are related to the planning levels presented by Ulrich (Syst Prac 1(4):415–428, 1988). It was chosen to focus on the understanding of a sustainable transport planning process. This focus is addressed by four stakeholder groups interviewed based on the ‘ought to’ mode of Critical Systems Heuristics (CSH). Finally an outline of some of the factors of a sustainable transport planning process is proposed.     

A security patch for a three-party key exchange protocol

The CLC protocol (proposed by Tzung-Her Chen, Wei-Bin Lee and Hsing-Bai Chen, CLC, for short) is a new three-party password-authenticated key exchange (3PAKE) protocol. This CLC protocol provides a superior round efficiency (only three rounds), and its resources required for computation are relatively few. However, we find that the leakage of values A _V and B _V in the CLC protocol will make a man-in-the-middle attack feasible in practice, where A _V and B _V are the authentication information chosen by the server for the participants A and B. In this paper, we describe our attack on the CLC protocol and further present a modified 3PAKE protocol, which is essentially an improved CLC protocol. Our protocol can resist attacks available, including man-in-the-middle attack we mount on the initial CLC protocol. Meanwhile, we allow that the participants choose their own passwords by themselves, thus avoiding the danger that the server is controlled in the initialization phase. Also, the computational cost of our protocol is lower than that of the CLC protocol.     

Dynamic domain decomposition method and its application on nonlinear problem

In this paper,domain decomposition method(DDM) for numerical solutions of mathematical physics equations is improved into dynamic domain decomposition method(DDDM) . The main feature of the DDDM is that the number,shape and volume of the sub-domains are all flexibly changeable during the iterations,so it suits well to be implemented on a reconfigurable parallel computing system. Convergence analysis of the DDDM is given,while an application approach to a weak nonlinear elliptic boundary value problem and a ...     

Regularization strategy for the Cauchy problem of Laplace’s equation from the viewpoint of regularization theory

Within the framework of the regularization theory, a spectral regularization method is introduced and analyzed. The convergence estimate under an appropriate choice of regularization parameter is obtained. A numerical implementation is described. Numerical examples show that the proposed method is effective and stable.     

与专业方向相结合的程序设计类公共选修课教学研究

针对高校公共选修课特点及其开设目的,以程序设计类课程为例,对当前公共选修课教学过程中存在的问题进行了分析,提出一种与专业方向相结合的程序设计类公共选修课教学模式,并对其实施方法进行了阐述。采用这种教学模式,能够有效满足学生的多样化需求,提高学生的学习兴趣和拓宽学生知识面,进而能够提高公共选修课的教学质量。     

A new approach of available transfer capability incorporating wind generation

The approach of available transfer capability (denoted as ATC) incorporating wind generation has been paid very high attention since the development of wind generation. Based on the maximum function, this paper presents an ATC model. The characteristic of the new model is twofold. First, it considers wind turbines connected to power system and static security of power system simultaneously. Second, it is a system of semismooth equations and can be solved easily. By using the smoothing strategy, a smoothing Newton method is adopted for solving the proposed new ATC model. Numerical simulation results of the IEEE 30-bus and 118-bus system show that the new model and algorithm are feasible and effective. The impact of wind turbines connected to power system on ATC is also analyzed.     

Accurate localization and excision of genomic islands in four strains of <Emphasis Type="Italic">Pseudomonas aeruginosa</Emphasis> and <Emphasis Type="Italic">Pseudomonas fluorescens</Emphasis>

Mobile genomic islands (GIs) can be excised from the chromosome, then form a circular intermediate and be reintegrated into the chromosome by the GI internal integrase. Some mobile GIs can also be transferred into a new receptor cell by transformation, conjugation, or transduction. The action sites of the integrase are usually flanked direct repeats (DRs) of the GIs. Accurate localization of the flanking sequences is a precondition for determining the mobility of the GI. Mobile GIs are generally associated with transfer RNAs (tRNAs). Based on the correlation between flanking sequences and tRNA sequences, the flanking sequences of 11 putative mobile GIs in Pseudomonas aeruginosa PAO1, P. aeruginosa PA14, P. fluorescens Pf-5 and P. fluorescens Pf0-1 were identified. Among the 11 GIs, Pf0-1GI-1 is responsible for benzoate degradation. PAO1GI-1, Pf5GI-2, Pf5GI-3, and Pf5GI-4 were confirmed experimentally to be excised from a chromosome to form a circular intermediate. The action sites of the integrases are these GIs direct repeats. Due to distinct DRs, cutting sites for the internal integrase of PAO1GI-1, Pf5GI-2, Pf5GI-3 and Pf5GI-4 were determined outside the T-loop of the tRNA^Gly gene, outside the anticodon loop of the tRNA^Ser gene and tRNA^Lys gene, and at the asymmetric 3′-end of the tRNA^Leu gene, respectively. PAO1GI-1 and other mobile GIs may be transferred into many different strains that belong to different phyla because of the clear flanking sequences. This study describes basic information about the action sites of the integrases, assesses the mobility of GIs, and can help design and transfer mobile GIs to candidate strains.     

A liquid helium temperature target with a 10 K vapor shield for shock compression experiment in the environment condition of 100 Pa

The shock compression experiment of liquid helium is an available way to gain properties of specimen at high temperatures and pressures.Based on Fluent,a thermal insulation analysis and design of a liquid helium temperature target in the environment condition of 100 Pa for shock compression experiment is performed.Then,a cryogenic target with a 10 K helium vapor shield and a separated vacuum interval is particularly developed.A lowest temperature of 3.63 K and a stable temperature of 3.70 K in the specimen cavity with an accuracy of 0.1 K are obtained by means of continuous flow and vacuum cooling.Both time-consuming and temperature stability are well-suited to the requirements of the shock compression experiment.The results show that the calculated and experimental data well-matched each other.The simulation method may be effective and feasible for the optimal design of the cryogenic target.