Inference systems for observation equivalences in the π-calculus

Inference systems for observation equivalences in the pi-calculus with recursion are proposed, and their completeness over the finite-control fragment with guarded recursions are proven. The inference systems consist of inference rules and equational axioms. The judgments are conditional equations which characterise symbolic bisimulations between process terms. This result on the one hand generalises Milner's complete axiomatisation of observation equivalence for regular CCS to the pi-calculus, and on the other hand extends the proof systems of strong bisimulations for guarded regular pi-calculus to observation equivalences.     

Diagenetic evolution and its effect on reservoir-quality of fan delta sandstones during progressive burial: Evidence from the upper part of the fourth member of Shahejie formation,Bonan sag,Jiyang depression

Petrographic analysis combined with various techniques, such as thin section identification, fluid inclusions, isotopic data, petro-physical property testing and oil testing results, was used to study diagenetic evolution and its effect on reservoir-quality of fan delta reservoirs of Es4s in the Bonan sag. The diagenesis is principally characterized by strong compaction, undercompaction, multi-phase of dissolution and cementation. Compaction played a more important role than cementation in destroying the primary porosity of the sandstones. The reservoirs have experienced complicated diagenetic environment evolution of "weak alkalineacid-alkalinity-acid-weak alkalinity" and two-stage of hydrocarbon filling. The diagenetic sequences are summarized as "early compaction/early pyrite/gypsum/calcite/dolomite cementation→feldspar dissolution/the first stage of quartz overgrowth → early hydrocarbon filling→quartz dissolution/anhydrite/Fe-carbonate cementation→Fe-carbonate dissolution/feldspar dissolution/ the second stage of quartz overgrowth→later hydrocarbon filling→later pyrite cementation. In the same diagenetic context, the diagenetic evolution processes that occurred in different sub/micro-facies during progressive burial have resulted in heterogeneous reservoir properties and oiliness. The braided channel reservoirs in fan delta plain are poorly sorted with high matrix contents. The physical properties decrease continually due to the principally strong compaction and weak dissolution. The present properties of braided channel reservoirs are extremely poor, which is evidenced by few oil layers developed in relatively shallow strata while dry layers entirely in deep. The reservoirs both in the underwater distributary channels and mouth bars are well sorted and have a strong ability to resist compaction. Abundant pores are developed in medium-deep strata because of modifications by two-stage of acidic dissolution and hydrocarbon filling. The present properties are relatively well both in the underwater distributary channels and mouth bars and plenty of oil layers are developed in different burial depth. The present reservoir properties both in interdistributary channel and pre-fan delta are poor caused by extensively cementation. Small amounts of oil layers, oil-water layers and oil-bearing layers are developed in relatively shallow strata while dry layers totally in deep.     

Bounds on Fractional Domination of Some Products of Graphs

Let γ f(G) and γ~t f(G) be the fractional domination number and fractional total domination number of a graph G respectively. Hare and Stewart gave some exact fractional domination number of P n×P m (grid graph) with small n and m . But for large n and m , it is difficult to decide the exact fractional domination number. Motivated by this, nearly sharp upper and lower bounds are given to the fractional domination number of grid graphs. Furthermore, upper and lower bounds on the fractional total domination number of strong direct product of graphs are given.     

Diurnal variations of turbulence parameters over the tropical oceanic upper troposphere during SCSMEX

Using the method of Thorpe analysis,the TKE(turbulence kinematic energy)dissipation rate(ε)and turbulence diffusivity(K)were derived from the RS(radiosounding)measurements in the tropical oceanic upper troposphere.The measurements were performed four times per day during two intense observation periods(May 5–25,and June 5–25)on the Kexue#1 scientific observation ship of SCSMEX(South China Sea Monsoon EXperiment)in 1998.There are three new features obtained from our analysis.First,the responses ofεand K to the onset of monsoon are negligible over the ocean at least for the data used here.Second,the temporal variations ofεand K are in a similar manner and exhibit strong diurnal variations.The diurnal variations achieve their maxima in the morning(08 LT)and early afternoon(14 LT),and achieve their minima in the evening(20 LT)and early morning hours(02 LT).The diurnal variations of turbulence parameters(εand K)and their responses to the onset of monsoon are entirely different from those derived over land at similar latitudes.Finally,although the correlations between the variations ofεand MCSs(mesoscale convective systems),which were derived from TRMM(tropical rainfall measuring mission)satellite,are not very well in only few days,the diurnal variations ofεaveraged over May and June are strongly correlated with the diurnal variations of MCSs with correlation factors of 0.79 and 0.94,respectively.This indicates that the turbulence and its diurnal variations over the tropic oceanic upper stratosphere region are highly related to the MCSs.     

Implementation and control of asymmetric thermal environment in two-dimensional rectangular enclosure

Laminar natural convection in an enclosure divided by an adiabatic partition on its bottom with two unequal discrete heat sources was investigated numerically. The effect of the partition on the flow structure and heat transfer characteristics in enclosure under asymmetric heating condition was studied. The parameters are the Rayleigh number (1 × 104 ≤Ra≤1 × 106) and the height of partition (0≤h/H≤0. 70). The streamlines are produced for various Rayleigh numbers. The results reflected by variations of the average Nusselt number in terms of the height of partition illustrates the convection heat transfer in the enclosure. The role of the partition is to weaken or cut off the heat removal rate from the strong heat source to the weak heat source. It is analyzed that the optimum height of the partition to break the linkage between the strong and weak heat source increases with increasing Rayleigh number.     

Pettis—Aumann Integration

The discussion about the integration of set-valued mapping was made in the strong sense. But, many set-valued mappings are not strong integrablc. So, in this paper, the integration of set-valued mapping in weak sense is defined in Banach space, which is called Pettis-Aumann Integration, and the properties of this integration are discussed. The relationship between strong and weak integration and the convexity theorem are established.     

Random Vibration Analysis of the Electronic Equipment Cabinet

In order to understand the vibration characteristic of system structure of electronic equipment cabinet within the particular vibration frequency,the finite element analysis software-ANSYS is used to simulate the tests of random vibrations of the cabinet system and obtain the isopleths graph of deformation and stress of the cabinet.It can confirm maximum of deformation and stress of the cabinet and position happened.Through more analysis of the frequency response curve,which can confirm harm- ful consequences random vibrations caused and weak link of the cabinet structure.The numerical simulation results are in good a- greement with the experimental results.It shows that this research provides an efficient method for the anti-seismic design and the dynamic optimization design.     

Nonlinear symbolic LFT model for UAV

A nonlinear modeling framework is presented for an oceanographic unmanned aerial vehicle(UAV)by using symbolic modeling and linear fractional transformation(LFT)techniques.Consequently,an exact nonlinear symbolic LFT model of the UAV is derived in a standard M-Δform where M represents the nominal,known,part of the system andΔcontains the time-varying,uncertain and nonlinear components.The advantages of the proposed modeling approach are that:it not only provides an ideal starting point to obtain various final design-oriented models through subsequent assumptions and simplifications,but also it facilitates the control system analysis with models of different levels of fidelity/complexity.Furthermore,a linearized symbolic LFT model of the UAV is proposed based on the LFT differentiation,which is amenable directly to a sophisticated linear robust control strategy such asμsynthesis/analysis.Both of the derived LFT models are validated with the original nonlinear model in time domain.Simulation results show the effectiveness of the proposed algorithm.     

A version management model of PDM system and its realization

Based on the key function of version management in PDM system,this paper discusses the function and the realization of version management and the transitions of version states with a workflow.A directed acyclic graph is used to describe a version model.Three storage modes of the directed acyclic graph version model in the database,the bumping block and the PDM working memory are presented and the conversion principle of these three modes is given.The study indicates that building a dynamic product structure configuration model based on versions is the key to resolve the problem.Thus a version model of single product object is built.Then the version management model in product structure configuration is built and the application of version management of PDM system is presented as a case.     

An optimized framework for degree distribution in LT codes based on power law

LT codes are practical realization of digital fountain codes, which provides the concept of rateless coding. In this scheme, encoded symbols are generated infinitely from k information symbols. Decoder uses only(1+α)k number of encoded symbols to recover the original information. The degree distribution function in the LT codes helps to generate a random graph also referred as tanner graph. The artifact of tanner graph is responsible for computational complexity and overhead in the LT codes. Intuitively, a well designed degree distribution can be used for an efficient implementation of LT codes. The degree distribution function is studied as a function of power law, and LT codes are classified into two different categories: SFLT and RLT codes. Also, two different degree distributions are proposed and analyzed for SFLT codes which guarantee optimal performance in terms of computational complexity and overhead.     

Theory of loop algebra on multi-loop kinematic chains and its application

Based on the mathematic representation of loops of kinematic chains, this paper proposes the " ⊕ " operation of loops and its basic laws and establishes the basic theorem system of the loop algebra of kinematic chains. Then the basis loop set and its determination conditions, and the ways to obtain the crucial perimeter topological graph are presented. Furthermore, the characteristic perimeter topo-logical graph and the characteristic adjacency matrix are also developed. The most important characteristic of this theory is that for a topological graph which is drawn or labeled in any way, both the resulting characteristic perimeter topological graph and the characteristic adjacency matrix obtained through this theory are unique, and each has one-to-one correspondence with its kinematic chain. This character-istic dramatically simplifies the isomorphism identification and establishes a theoretical basis for the numeralization of topological graphs, and paves the way for numeralization and computerization of the structural synthesis and mechanism design further. Finally, this paper also proposes a concise isomorphism identifica-tion method of kinematic chains based on the concept of characteristic adjacency matrix.     

Progress of entransy analysis on the air-conditioning system in buildings

It is of great importance to improve the energy performance of the air-conditioning system for building energy conversation. Entransy provides a novel perspective to investigate the losses existing in the air-conditioning system. The progress of entransy analysis in the air-conditioning system is comprehensively investigated in the present study. Firstly missions and characteristics of the air-conditioning system are analyzed with emphasis on heat or mass transfer process. It is found that reducing the temperature difference, i.e. reducing the entransy dissipation helps to improve the performance. Entransy dissipations and thermal resistances of typical transfer processes in the air-conditioning system are presented. Characteristics of sensible heat transfer process and coupled heat and mass transfer processes are researched in terms of entransy dissipation analysis. Reasons leading to entransy dissipation are also clarified with the help of unmatched coefficient ξ. Principles for reducing the entransy dissipation and constructing a high temperature cooling system are summarized on the basis of case studies in typical handling processes. It's recommended that reducing mixing process, improving match properties are main approaches to reduce the entransy dissipation. The present analysis is beneficial to casting light on the essence of the air-conditioning system and proposing novel approaches for performance optimization.     

Rockburst mechanism in soft coal seam within deep coal mines

A number of rockburst accidents occurring in soft coal seams have shown that the rockburst mechanism involved in soft coal seams is significantly different from that involved in hard coal seams. Therefore, the method used to evaluate rockburst in hard coal seams is not applicable to soft coal seams. This paper established an energy integral model for the rockburst-inducing area and a friction work calculation model for the plastic area. If the remaining energy after the coal seam is broken in the rockburstinducing area is greater than the friction work required for the coal to burst out, then a rockburst accident will occur. Mechanisms of ‘‘quaking without bursting" and ‘‘quaking and bursting" are clarified for soft coal seams and corresponding control measures are proposed as the optimization of roadway layouts and use of ‘‘three strong systems"(strong de-stressing, strong supporting, and strong monitoring).     

Simulation of Artificial Grain Feeding in Order to Reach Dynamical Bed Stabilisation Along the River Rhine

The Wesel-Xanten stretch of the fiver Rhine between km-812.5 and km-821.5 is one of the reaches where strong erosion leads to high maintenance efforts conceming navigability.In order to improve the naviga- tion conditions without aggravating the flood protection,but also ensuring that the ecological system of the river is not damaged,investigations of the morphodynamical processes in connection with artificial grain feeding ac- tivities have to be carried out by Federal Waterways Engineering and Research Institute.The performance of artificial grain feeding along a stretch of the lower Rhine near Wesel to prevent bed erosion by balancing sedi- ment transport was simulated in a scientific way by sensitivity studies in a 2D depth-average numerical model with graded sediment transport approach.The target of the investigations is to study the interaction of bed load supply and hydro-/morphodynamical features,and then especially to analyse and control the grain feeding measures in this section of the Rhine river.First the administrative background and target of artificial grain feeding along the waterways and then the special features regarding flow and transport characteristics of the stretch are described.After introducing shortly the mathematical basis for modelling graded sediment transport and some special treatments for the case of artificial grain feeding activities,some validation results for graded sediment are discussed.A series of numerical simulations with the objective of testing the model sensitivity to different model parameters has been carried out.Further,results of numerical simulations for the case of grain feeding are presented.     

Complete characterization of strictly positive real regions and robust strictly positive real synthesis method

The concept of weak strictly positive real regions is introduced, and its properties are discussed . By using the complete discrimination system for polynomials, complete characterization of the (weak) strictly positive real regions for transfer functions in coefficient space is given. A new effective method for robust strictly positive real synthesis is proposed. This method results in necessary and sufficient conditions for low-order stable interval polynomials and segment polynomials, and is also efficient for high-order cases. Numerical examples are provided to illustrate the effectiveness of this method.     

GPU acceleration of subgraph isomorphism search in large scale graph

A novel framework for parallel subgraph isomorphism on GPUs is proposed, named GPUSI, which consists of GPU region exploration and GPU subgraph matching. The GPUSI iteratively enumerates subgraph instances and solves the subgraph isomorphism in a divide-and-conquer fashion. The framework completely relies on the graph traversal, and avoids the explicit join operation. Moreover, in order to improve its performance, a task-queue based method and the virtual-CSR graph structure are used to balance the workload among warps, and warp-centric programming model is used to balance the workload among threads in a warp. The prototype of GPUSI is implemented, and comprehensive experiments of various graph isomorphism operations are carried on diverse large graphs. The experiments clearly demonstrate that GPUSI has good scalability and can achieve speed-up of 1.4–2.6 compared to the state-of-the-art solutions.     

Distributed coordinated adaptive tracking in networked redundant robotic systems with a dynamic leader

Distributed coordinated control of networked robotic systems formulated by Lagrange dynamics has recently been a subject of considerable interest within science and technology communities due to its broad engineering applications involving complex and integrated production processes,where high flexibility,manipulability,and maneuverability are desirable characteristics.In this paper,we investigate the distributed coordinated adaptive tracking problem of networked redundant robotic systems with a dynamic leader.We provide an analysis procedure for the controlled synchronization of such systems with uncertain dynamics.We also find that the proposed control strategy does not require computing positional inverse kinematics and does not impose any restriction on the self-motion of the manipulators;therefore,the extra degrees of freedom are applicable for other sophisticated subtasks.Compared with some existing work,a distinctive feature of the designed distributed control algorithm is that only a subset of followers needs to access the position information of the dynamic leader in the task space,where the underlying directed graph has a spanning tree.Subsequently,we present a simulation example to verify the effectiveness of the proposed algorithms.     

Manufacturing cost optimization and estimation combined computer of composite-stiffened panels

The primary goal of this study is to fully grasp the production flow of the new processing technologies for manufacturing composite stiffened panels incorporating cost as one of the design variables early in the design process. An approach is presented to determine the optimum process for cost as objective function. A cost estimation model is established based on the integrally molding process. In the model,the cost drivers which are related to the manufacture processes in terms of material,labor,tool and equipment costs are taken into account. At the same time,estimation software combined computer is developed to aid optimization design. A case of manufacturing composite stiffened panels with T-shaped stiffeners is examined. Excellent agreement shows the optimum process for cost is obtained for the composite stiffened panel with cocuring. It is also revealed that the estimation software combined computer is efficient. The estimation methodology is valid to guide design of the manufacturing process for the composite-stiffened panel.     

Monitoring actual performance of ground source heat pump system using GPRS-based data transmission: A case analysis in Tangshan

The energy efficiency monitoring is an essential precondition for ground source heat pump system’s controlling and energy saving operation. Based on the data monitoring applied in the school building, this work is focused on the parameters acquisition and operation analysis of the GSHP system in Tangshan. Results show the average COPs(coefficient of performance) are2.85 and 2.70 in summer and winter, respectively, and heat(cold) unbalance underground existed after whole year operation. The analysis of data also indicates that the direct borehole air-conditioning saved some power consumption obviously in the early stage of summer and energy saving of the GSHP system depended remarkably on its operation and management level. Besides the observation points of ground temperature are laid for a large-scale GSHP system, and the hydraulic balance of the pipes group needs to be concerned specially in safeguarding better reliability.     

A segment version transcoding for client-centric wireless mobile media streaming

An object segment similarity function is taken into account from the continuous media frames to measure the individual streaming profit of certain segment versions of a media object.Therefore,a new segment version-based transcoding （SVT） mechanism is derived for a quality of service （QoS） of client-centric media streaming in wireless mobile networks.The derived function utilizes the fuzzy similarity of certain segment versions of an object.This mechanism provides the effectiveness of reduction of the stream startup latency among segment versions,and the average access of each version.Thus,the proposed segment version transcoding mechanism reduces packet loss which in turn increases streaming performance and throughput.The performance of the partitioned segment versions is simulated and some segment versions are completed.The simulation results show that the proposed mechanism outperforms the other mechanisms in average cache hit ratio and in average startup latency ratio.