Growth and length-weight parameters of Pacific mackerel (Scomber japonicus) in the Gulf of Guayaquil, Ecuador

The seasonally oscillating growth parameters and length-weight relationships for Scomber japonicus caught in the Gulf of Guayaquil, Ecuador, were determined based on length-frequency data from 1989 to 1996, using the FiSAT software package of Gayanilo et al. (1996). Estimates of growth parameters are in general agreement with previous studies on the same species. Results also imply that the growth of Scomber japonicus slows down during the cold season by approximately 50% with respect to the average growth. The mean value of the power b is significantly larger than 3, indicating that the model of allometric growth should be used for the length-weight relationship and calculation of the condition factor.

Seasonal growth of five commercially important fishes at Sofala Bank, Mozambique

An analysis of growth of scad and mackerels on Sofala Bank, Mozambique, was performed using data collected from commercial vessels during the year 1986-87, using the "Compleat Elefan" software package. Updated estimates of growth parameters of Decapterus russelli, D. macrosoma (Carangidae), and Rastrelliger kanagurta (Scombridae) were obtained which take seasonal growth oscillations into account. Preliminary growth parameter estimates are also presented for Selar crumenophthalmus (Carangidae) and Saurida undosquamis (Synodontidae).

The use of object oriented modelling and simulation tools in constraint satisfaction for embodiment design

The software package Dymola, which implements the new, vendor-independent standard modelling language Modelica, exemplifies the emerging generation of object-oriented modelling and simulation tools. This paper shows how, in addition to its simulation capabilities, it may be used as an embodiment design tool, to size automatically a design assembled from a library of generic parametric components. The example used is a miniature model aircraft diesel engine. To this end, the component classes contain extra algebraic equations calculating the overload factor (or its reciprocal, the safety factor) for all the different modes of failure, such as buckling or tensile yield. Thus the simulation results contain the maximum overload or minimum safety factor for each failure mode along with the critical instant and the device state at which it occurs. The Dymola "Initial Conditions Calculation" function, controlled by a simple software script, may then be used to perform automatic component sizing. Each component is minimised in mass, subject to a chosen safety factor against failure, over a given operating cycle. Whilst the example is in the realm of mechanical design, it must be emphasised that the approach is equally applicable to the electrical or mechatronic domains, indeed to any design problem requiring numerical constraint satisfaction.

Mandrel peeling of a flexible laminate with a pressure-sensitive adhesive: Comparison of experiment with numerical analysis

Mandrel peel tests with mandrels or rollers of varying diameters have been carried out using Mylar backing of several thicknesses and a commercial synthetic acrylic adhesive. The results are critically compared with the numerical predictions of the peeling software package ICPeel. In addition, a finite element model of the mandrel peeling process has been completed which gives good agreement with experiment provided appropriate mechanical properties of adherend and adhesive are used which must include the effects of adherent constraint. The influence of the thickness of the backing is also considered and both experiment and analysis confirm that there is a backing thickness at which the peel force for a laminate of this sort will show a maximum. © 2010 Blackwell Publishing Ltd.

Biology of the penaeid shrimp populations exploited by Estuarine Set Bagnet

Results of analysis of part of the data collected during October, 1989 to December, 1990 are given on the biology and catch assessment studies on the Estuarine Set Bagnet (ESBN) from six sampling stations covering the entire coast line of Bangladesh. Length frequency analysis of seven most commonly occurring penaeid shrimp species have been done with complete ELEFAN software package. The result of exploitation patterns indicate that all penaeids except P. stylifera are being over exploited on their way back to the Sea from the nursery ground. This appeared to be the instances of serious growth over fishing. These species are exploited at a size much lower than the length at first maturity, which strongly suggests a complete withdrawal of the bagnet fishery from the coast of Bangladesh.

Molecular modeling on some human interleukins sharing gamma c of interleukin-2 receptor, and structure-function relationships

Five models for human interleukin-7 (HIL-7), HIL-9, HIL-13, HIL-15 and HIL-17 have been generated by SYBYL software package. The primary models were optimized using molecular dynamics and molecular mechanics methods. The final models were optimized using a steepest descent algorithm and a subsequent conjugate gradient method. The complexes with these interleukins and the common gamma chain of interleukin-2 receptor (IL-2R) were constructed and subjected to energy minimization. We found residues, such as Gln127 and Tyr103, of the common gamma chain of IL-2R are very important. Other residues, e.g. Lys70, Asn128 and Glu162, are also significant. Four hydrophobic grooves and two hydrophilic sites converge at the active site triad of the gamma chain. The binding sites of these interleukins interaction with the common gamma chain exist in the first helical and/or the fourth helical domains. Therefore, we conclude that these interleukins binds to the common gamma chain of IL-2R by the first and the fourth helix domain. Especially at the binding sites of some residues (lysine, arginine, asparagine, glutamic acid and aspartic acid), with a discontinuous region of the common gamma chain of IL-2R, termed the interleukins binding sites (103-210). The study of these sites can be important for the development of new drugs. (C) 2000 Elsevier Science B.V. All rights reserved.

Implementation of multi-group cross-section methodology in BGCore MC-depletion code

BGCore is a software package for comprehensive computer simulation of nuclear reactor systems and their fuel cycles. The BGCore interfaces Monte Carlo particles transport code MCNP4C with a SARAF module - an independently developed code for calculating in-core fuel composition and spent fuel emissions following discharge. In BGCore system, depletion coupling methodology is based on the multi-group approach that significantly reduces computation time and allows tracking of large number of nuclides during calculations. In this study, burnup calculation capabilities of BGCore system were validated against well established and verified, computer codes for thermal and fast spectrum lattices. Very good agreement in k eigenvalue and nuclide densities prediction was observed for all cases under consideration. In addition, decay heat prediction capabilities of the BGCore system were benchmarked against the most recent edition of ANS Standard methodology for UO2 fuel decay power prediction in LWRs. It was found that the difference between ANS standard data and that predicted by the BGCore does not exceed 5%.

Assessing boost-assist options for turbocharged engines using 1-D engine simulation and model predictive control

Delivering acceptable low end torque and good transient response is a significant challenge for all turbocharged engines. As downsized gasoline engines and Diesel engines make up a larger and larger proportion of the light-duty engines entering the market, the issue takes on greater significance. Several schemes have been proposed to improve torque response in highly boosted engines, including the use of electrical assist turbochargers and compressed air assist. In this paper we examine these methods with respect to their effectiveness in improving transient response and their relative performance along with some of the practical considerations for real world application. Results shown in this paper are from 1-D simulations using the Ricardo WAVE software package. The simulation model is based on a production light-duty Diesel engine modified to allow the introduction of compressed air at various points in the air-path as well as direct torque application to the turbocharger shaft (such as might be available from an electrical assist turbocharger). Whilst the 1-D simulation software provides a suitable environment for investigating the various boost assistance options, the overall air path performance also depends upon the control system. The introduction of boost assistance complicates the control in two significant ways: the system may run into constraints (such as compressor surge) that are not encountered in normal operation and the assistance introduces an additional control input. Production engine controllers are usually based on gain-scheduled PID control and extensive calibration. For this study, the non-linear nature of the engine together with the multiple configurations considered and the slower than real-time execution of 1-D models makes such an approach time consuming. Moreover, an ad-hoc approach would leave some doubt as to the fairness of comparisons between the different boost-assist options. Model Predictive Control has been shown to offer a convenient approach to controlling the 1-D simulations in a close to optimal manner for a typical Diesel VGT-EGR air path configuration. We show that the same technique can be applied to all the considered assistance methods with only modest calibration effort required. Copyright © 2012 SAE International.

超图划分与SFC的比较研究和数值软件可视化界面

本文重点对超图划分和空间填充曲线两类算法进行比较研究。在大规模科学计算的中，并行计算效率提升的一个关键在于将数据进行剖分，分配到相应处理器中，以及对处理器中的数据进行动态调整，数据剖分和数据调整是实现处理器节点之间负载均衡的关键。针对数据剖分和数据调整问题，目前主要通过两类手段解决，分别称为拓扑手段和几何手段。而超图划分和空间填充曲线作为这两类手段的代表，在数据剖分和数据调整过程中得到了广泛的应用。 解决超图划分问题的经典算法中，应用最为广泛是启发式算法，如FM算法等。本文以FM算法为例，给出了较为详细的分析。随着问题规模的不断扩大，这些传统的算法消耗的时间急剧增加，研究者们因此又提出了对超图进行多级划分的算法框架。本文将对这一算法框架的各阶段细节进行分析。 空间填充曲线可以对离散的多维空间进行线性遍历，将多维的问题转化为一维的问题。利用这种特性，在数据剖分过程中可以将数据进行排序，根据这一顺序对数据进行剖分。本文对空间填充曲线的生成和应用，以及几类常用的空间填充曲线的顺序编码生成算法进行分析。 超图划分和空间填充曲线在数据剖分应用中各有优缺点。超图划分对节点间通信量等优化目标可以进行更为准确的计算，可以得到对更为有效的减少节点间通信量的数据剖分，但是超图划分这一过程本身所需要的时间较多；而空间填充曲线可以在很短的时间内对数据进行剖分，但是无法对优化目标进行准确计算。我们对两者在数据剖分中的应用，以及应用不同的划分模型对整体计算的影响进行了分析比较，并进行了实验对观点进行了验证。 在文章的最后，结合实际项目对数值软件可视化界面的设计进行了阐述。

建立在小型计算机上的GPSS-F/1000通用仿真软件包

本文阐述了在小型计算机上建立的 GPSS-F/1000通用仿真软件包。该软件包不仅具有原 GPSS-F仿真软件的全部功能,并且使公用数组、系统参数的适配全部活化,通过子程序的形式参量传送赋给,从而,仿真时不必修改子程序的源程序。此外,增加了统计参数估计子程序集和图形绘制子程序集。

绘图专用字符库的建立与使用

本文概述了用专门的造字符软件 SYGEN 交互式地建立“绘图专用字符库”(包括汉字)的方法。文中着重论述了如何对国外引进的软件 SYGEN,在建库的设计思想,提高字符的存取速度,减少内、外存空间的占有等方面进行的改造,从而,用此方法能够简单而快速地建立使用方便、易于更新的绘图专用字符库。

扩展CSS仿真程序及其应用

本文介绍了一个连续-离散复合仿真程序。该程序的连续部分基本取自美国的 CSS 程序。经作者扩充后成为复合仿真程序。扩充的模块包括采样系统仿真模块、两点边值问题求解以及参量最优化等。作者提出的单纯形搜索法改进策略可以显著加快参量最优化过程的收敛速度。

井间地震速度层析成像方法与软件系统

Crosshole Seismic tomography has been broadly studied and applied in the fields of resource exploration and engineering exploration because of its special observing manner and better resolution than normal seismic exploration. This thesis will state the theory and method of Crosshole Seismic tomography. Basing on the previous studies，the thesis studied the initial velocity model，ray-tracing method, and developed the three-dimension tomography software. All the cells that a ray passes through are of the same velocities if the paths from transmitters to receivers are straight. The cells that the each ray passes through are recorded, and rays that pass through each cell are calculated. The ray average velocity which passes through a cell is set as the cell velocity. Analogously we can make a initial node velocity model because the velocity sum is calculated on the all cells which own to a certain node, and the cell number is summed about each nodes，the ratio of the velocity sum to the all cells number is set as the node velocity. The inversion result from the initial node velocity model is better than that of the average velocity model. Ray-bending and Shortest Path for Rays (SPR) have shortcomings and limitations respectively. Using crooked rays obtained from SPR rather than straight lines as the starting point can not only avoid ray bending converging to the local minimum travel time path, but also settle the no smooth ray problem obtained by SPR. The hybrid method costs much computation time, which is roughly equal to the time that SPR expends. The Delphi development tool based on the Object Pascal language standard has an advantage of object-oriented. TDTOM (Three Dimensions Tomography) was developed by using Delphi from the DOS version. Improvement on the part of inversion was made, which bring faster convergence velocity. TDTOM can be used to do velocity tomography from the first arrival travel time of the seismic wave, and it has the good qualities of friendly user interface and convenient operation. TDTOM is used to reconstruct the velocity image for a set of crosshole data from Karamay Oil Field. The geological explanation is then given by comparing the inversion effects of different ray-tracing methods. High velocity zones mean the cover of oil reservoir, and low velocity zones correspond to the reservoir or the steam flooding layer.

泥岩裂缝储层地震识别的理论和方法

During the exploration of fractured reservoirs, worldwide difficult problems will be encountered: how to locate the fractured zones, how to quantitatively determine the azimuth, density, and distribution of the fractures, and how to compute the permeability and porosity of the fractures. In an endeavor to solve these problems, the fractured shale reservoir in SiKou area of ShengLi oil field was chosen as a study area. A study of seismic predictive theory and methods for solving problems encountered in fractured reservoir exploration are examined herein. Building on widely used current fractured reservoir exploration techniques, new seismic theories and methods focusing on wave propagation principles in anisotropic medium are proposed. Additionally, integrated new seismic data acquisition and processing methods are proposed. Based on research and application of RVA and WA methods from earlier research, a new method of acoustic impedance varying with azimuth (IPVA) creatively is put forth. Lastly combining drilling data, well log data, and geologic data, an integrated seismic predictive method for cracked reservoir bed was formed. A summary of the six parts of research work of this paper is outlined below. In part one, conventional geologic and geophysical prediction methods etc. for cracked reservoir exploration are examined, and the weaknesses of these approaches discussed. In part two, seismic wave propagation principles in cracked reservoirs are studied. The wave equation of seismic velocity and attenuation factor in three kinds of fracture mediums is induced, and the azimuth anisotropy of velocity and attenuation in fracture mediums is determined. In part three, building on the research and application of AVA and WA methods by a former researcher, a new method of acoustic impedance creatively varying with azimuth (IPVA) is introduced. A practical software package utilizing this technique is also introduced. In part four, Base on previously discussed theory, first a large full azimuth 3d seismic data (70km~2) was designed and acquired. Next, the volume was processed with conventional processing sequence. Then AVA, WA, and IPVA processing was applied, and finally the azimuth and density of the fractures were quantitatively determined by an integrated method. Predictions were supported by well data that indicate the approach is highly reliable. in part five, geological conditions contributing to cracked reservoir bed formation are analyzed in the LuoJia area resulting in the discovery that the main fractured zones are related to fault distribution in the basin, that also control the accumulation of the oil and gas, the generation mechanisms and types of fractured shale reservoirs are studied. Lastly, by using full 3D seismic attributes, azimuth and density of cracked reservoir zones are successfully quantitative predicted. Using an integrated approach that incorporates seismic, geologic and well log data, the best two fractured oil prospects in LouJia area are proposed. These results herein represent a break through in seismic technology, integrated seismic predictive theory, and production technology for fractured reservoirs. The approach fills a void that can be applied both inside China, and internationally. Importantly, this technique opens a new exploration play in the ShengLi oil field that while difficult has substantial potential. Properly applied, this approach could play an important role toward stabilizing the oil field' production. In addition, this technique could be extended fracture exploration in other oil fields producing substantial economic reward.

A Perturbation Scheme for Spherical Arrangements with Application to Molecular Modeling

We describe a software package for computing and manipulating the subdivision of a sphere by a collection of (not necessarily great) circles and for computing the boundary surface of the union of spheres. We present problems that arise in the implementation of the software and the solutions that we have found for them. At the core of the paper is a novel perturbation scheme to overcome degeneracies and precision problems in computing spherical arrangements while using floating point arithmetic. The scheme is relatively simple, it balances between the efficiency of computation and the magnitude of the perturbation, and it performs well in practice. In one O(n) time pass through the data, it perturbs the inputs necessary to insure no potential degeneracies and then passes the perturbed inputs on to the geometric algorithm. We report and discuss experimental results. Our package is a major component in a larger package aimed to support geometric queries on molecular models; it is currently employed by chemists working in "rational drug design." The spherical subdivisions are used to construct a geometric model of a molecule where each sphere represents an atom. We also give an overview of the molecular modeling package and detail additional features and implementation issues.