A CAPACITY EXPANSION PROBLEM WITH BUDGET CONSTRAINT AND BOTTLENECK LIMITATION

This paper considers a capacity expansion problem with budget constraint. Suppose each edge in the network has two attributes: capacity and the degree of difficulty. The difficulty degree of a tree T is the maximum. degree of difficulty of all edges in the tree and the cost for coping with the difficulty in a tree is a nondecreasing function about the difficulty degree of the tree. The authors need to increase capacities of some edges so that there is a spanning tree whose capacity can be increased to the maximum extent, meanwhile the total cost for increasing capacity as well as overcoming the difficulty in the spanning tree does not exceed a given budget D*. Suppose the cost for increasing capacity on each edge is a linear function about the increment of capacity, they transform this problem into solving some hybrid parametric spanning tree problems([1]) and propose a strongly polynomial algorithm.

Minimum Cost of Capacity Expansion for Time-Limited Transportation Problem On-Demand

The minimum cost of capacity expansion for time-limited transportation problem on-demand (MCCETLTPD) is to find such a practicable capacity expansion transportation scheme satisfying the time-limited T along with all origins’ supply and all destinations’ demands as well as the expanding cost is minimum. Actually, MCCETLTPD is a balance transportation problem and a variant problem of minimum cost maximum flow problem. In this paper, by creating a mathematical model and constructing a network with lower and upper arc capacities, MCCETLTPD is transformed into searching feasible flow in the constructed network, and consequently, an algorithm MCCETLTPD-A is developed as MCCETLTPD’s solution method basing minimum cost maximum flow algorithm. Computational study validates that the MCCETLTPD-A algorithm is an efficient approach to solving the MCCETLTPD.

Lenzing Decides on Capacity Expansion Program

The Lenzing Group, world market leader in cellulose fibers, will continue to expand production capacity in 2010 by investing a scheduled EUR 120 million in its European and Asian sites.The projects will be realized over the next two years. The key elements are the

Microscopic experiment on efficient construction of underground gas storages converted from water-invaded gas reservoirs

Based on the microfluidic technology,a microscopic visualization model was used to simulate the gas injection process in the initial construction stage and the bottom water invasion/gas injection process in the cyclical injection-production stage of the underground gas storage(UGS)rebuilt from water-invaded gas reservoirs.Through analysis of the gas-liquid contact stabilization mechanism,flow and occurrence,the optimal control method for lifecycle efficient operation of UGS was explored.The results show that in the initial construction stage of UGS,the action of gravity should be fully utilized by regulating the gas injection rate,so as to ensure the macroscopically stable migration of the gas-liquid contact,and greatly improve the gas sweeping capacity,providing a large pore space for gas storage in the subsequent cyclical injection-production stage.In the cyclical injection-production stage of UGS,a constant gas storage and production rate leads to a low pore space utilization.Gradually increasing the gas storage and production rate,that is,transitioning from small volume to large volume,can continuously break the hydraulic equilibrium of the remaining fluid in the porous media,which then expands the pore space and flow channels.This is conducive to the expansion of UGS capacity and efficiency for purpose of peak shaving and supply guarantee.

Large-Capacity and High-Speed Instruction Cache Based on Divide-by-2 Memory Banks

An increase in the cache capacity is usually accompanied by a decrease in access speed.To balance the capacity and performance of caches,this paper proposes an instruction cache(ICache)architecture based on divide-by-2 memory banks(D2MB-ICache).The control circuit and memory banks of D2MB-ICache work at the central processing unit(CPU)frequency and the divide-by-2 CPU frequency,respectively,so that the capacity of D2MB-ICache can be expanded without lowering its frequency.For sequential access,D2MB-ICache can output the required instruction from memory banks per CPU cycle by dividing the memory banks with a partition mechanism and employing an inversed clock technique.For non-sequential access,D2MB-ICache will fetch certain jump instructions one or two more times,so that it can catch the jump of the request address in time and send the correct instruction to the pipeline.Experimental results show that,compared with conventional ICache,D2MB-ICaches with the same and double capacities show a maximum frequency increase by an average of 14.6%and 6.8%,and a performance improvement by an average of 10.3%and 3.8%,respectively.Moreover,energy efficiency of 64-kB D2MB-ICache is improved by 24.3%.

Anomalous low-temperature heat capacity in antiperovskite compounds

The low-temperature heat capacities are studied for antiperovskite compounds AX M_3（A = Al, Ga, Cu, Ag, Sn, X = C,N, M = Mn, Fe, Co）. A large peak in（C- γ T）/T^3 versus T is observed for each of a total of 18 compounds investigated,indicating an existence of low-energy phonon mode unexpected by Debye T^3 law. Such a peak is insensitive to the external magnetic field up to 80 k Oe（1 Oe = 79.5775 A·m-1）. For compounds with smaller lattice constant, the peak shifts towards higher temperatures with a reduction of peak height. This abnormal peak in（C- γ T）/T^3 versus T of antiperovskite compound may result from the strongly dispersive acoustic branch due to the heavier A atoms and the optical-like mode from the dynamic rotation of X M_6 octahedron. Such a low-energy phonon mode may not contribute negatively to the normal thermal expansion in AX M_3 compounds, while it is usually concomitant with negative thermal expansion in open-structure material（e.g., ZrW_2O_8, Sc F_3）.

Grouted Pile and Its Bearing Capacity

The grouting method applied in bored pile is an improvement to the conventional bored pile. Load tests have proved that grouting under the bored pile tip is an effective method to enhance the bearing capacity of the pile and to reduce the pile settlement. In this paper, the grouting technology is described and pile load test results are discussed. In order to put the grouting method into design practice, the authors analyze the working mechanism of soil compaction. And, based on the theory of cavities expansion in soil mass, approximate formulae are proposed for estimating the bearing capacity of the grouted pile. The theoretical prediction agrees well with the load test results.

Lignin Extraction from Black Liquor and its Application Prospects in Pulp Mills

This paper summarizes the possible application of lignin extraction from black liquor and the development of lignin extraction technology.Lignin extraction from black liquor is an important,economical method to resolve the bottleneck associated with the recovery boiler and achieve the targeted capacity expansion in pulp mills.A few of key issues must be taken into cosideration when lignin extraction technology is adopted on the industrial scale.

Multicriteria Analysis of a Capacity Expansion Problem:Damaturu, Northeastern Nigeria as Case Study

Damaturu, the Yobe State Capital is one of the major towns in the semi-arid areas OfNortheastern Nigeria. It lacks adequate water supply. Being a State Capital, rapid improvements in itsinfrastructures including water supply to cope with increased demands are required. Three options forthe expansion of the present water supply system are been considered. These are Groundwater resourceswithin and around the existing system, and surface water schemes from two Dam sites identitied andappraised for this purpose. The Management of the Yobe State Water Board and the State Governmentare faced with the problem of which of these three options to choose. This is a typical capacity expansionproblem within a multicriterion setting in which the choice is to be bassed on economic, environmental,social as well as political considerstions. This paper presents a multicriterion analysis whose result willbe used in forming the basis of an informed decision to be made on why a particular option is to bechosen.

China’s railway train speed,density and weight in developing

Purpose–This study aims to analyze the development direction of train speed,density and weight in China.Design/methodology/approach–The development of China’s railway in the past 40 years can be divided into 3 stages.At the stage of potential tapping and capacity expansion,it is important to improve the train weight and density by upgrading the existing lines,and improving transportation capacity rapidly.At the stage of railway speed increase,the first priority is to increase train speed,reduce the travel time of passenger train,and synchronously take into account the increase of train density and weight.At the stage of developing high-speed railway,train speed,density and weight are co-developing on demand.Findings–The train speed of high-speed railway will be 400 km h
1,the interval time of train tracking will be 3 min,and the traffic density will be more than 190 pairs per day.The running speed of high-speed freight EMU will reach 200 km h
1 and above.The maximum speed of passenger train on mixed passenger and freight railway can reach 200 km h
1.The minimum interval time of train tracking can be compressed to 5 min.The freight train weight of 850 m series arrival-departure track railway can be increased to 4,500–5,000 t and that of 1,050 m series to 5,500–6,400 t.EMU trains should gradually replace ordinary passenger trains to improve the quality of railway passenger service.Small formation trains will operate more in intercity railway,suburban railway and short-distance passenger transportation.Originality/value–The research can provide new connotations and requirements of railway train speed,density and weight in the new railway stage.