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941.
Cost estimation of structural skeleton using an interactive automation algorithm: A conceptual approach 总被引:1,自引:0,他引:1
This paper addresses a new concept for generating bills of quantities (B.o.Qs) using AutoCAD drawings for a building project, which demonstrates the application of Industry Foundation Class (IFC), developed by International Alliance for Interoperability (IAI). The procedure considers types of materials and the structural shapes of the AutoCAD drawings to compute the cost of the structural skeleton elements using interactive automation. The main concept focuses on using layer computation of the AutoCAD drawing after converting it into a drawing inter-exchangeable file format (DXF). Once the coordinates are detected, it is easier to determine the area and volume for any structural shape, including circles and polygons. The extracting method is a new technique for structural engineers and quantity surveyors to estimate required material for beam, columns, slabs and foundations. The algorithm extracts and recognizes the layers and objects from a two dimensional DXF drawing along with the coordinates information. The results obtained using this technique are more accurate and reliable than manual procedures or any other traditional techniques. In this paper, an automated and interactive procedure for B.o.Q computation is demonstrated. The process involves a user-friendly interface, dynamic linking to the structural drawings and tracking of B.o.Q modifications at the same time. 相似文献
942.
文章根据电机负荷理论对φ3m分级机螺旋轴进行受力分析,避免了复杂的推导计算和疲劳强度校核。根据现场实际,将机械技术与电气技术结合,分析其断裂原因,提出改进措施,具有较好的效果和借鉴价值。 相似文献
943.
李红宇 《数字社区&智能家居》2007,(17)
介绍了在VC .net的运行环境下运用拆分窗口功能实现界面切换的步骤及具体实现方法,并给出了关键的实现函数与事例. 相似文献
944.
E. Alvarez S. Landsberger 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2007,262(2):333-339
Prompt gamma activation analysis (PGAA), available at The University of Texas at Austin (UT), has been employed for the direct determination of hydrogen content in a series of metal oxide materials typically used as cathodes in lithium ion battery systems. Special attention was given to the experimental setup including potential sources of error and system calibration for the detection of hydrogen. Spectral interference with hydrogen arising from cobalt was identified and corrected for. Limits of detection as a function of cobalt mass present in a given sample are also discussed. PGAA has proven to be a novel and precise technique for the determination of hydrogen in metal oxides. This type of investigation could provide valuable insight regarding the factors that limit the practical capacities of lithium ion oxide cathodes. 相似文献
945.
The recently developed high-order accurate multiple image approximation to the reaction field for a charge inside a dielectric sphere [J. Comput. Phys. 223 (2007) 846-864] is compared favorably to other commonly employed reaction field schemes. These methods are of particular interest because they are useful in the study of biological macromolecules by the Monte Carlo and Molecular Dynamics methods. 相似文献
946.
Parallelization of the global extremum searching process 总被引:1,自引:0,他引:1
Yu. G. Evtushenko V. U. Malkova A. A. Stanevichyus 《Automation and Remote Control》2007,68(5):787-798
The parallel algorithm for searching the global extremum of the function of several variables is designed. The algorithm is based on the method of nonuniform coverings proposed by Yu.G. Evtushenko for functions that comply with the Lipschitz condition. The algorithm is realized in the language C and message passing interface (MPI) system. To speed up computations, auxiliary procedures for founding the local extremum are used. The operation of the algorithm is illustrated by the example of atomic cluster structure calculations. 相似文献
947.
Songhua Xu Haisheng Tan Xiantao Jiao Francis C.M. Lau Yunhe Pan 《Computer Graphics Forum》2007,26(3):609-618
We propose a generic pigment model suitable for digital painting in a wide range of genres including traditional Chinese painting and water-based painting. The model embodies a simulation of the pigment-water solution and its interaction with the brush and the paper at the level of pigment particles; such a level of detail is needed for achieving highly intricate effects by the artist. The simulation covers pigment diffusion and sorption processes at the paper surface, and aspects of pigment particle deposition on the paper. We follow rules and formulations from quantitative studies of adsorption and diffusion processes in surface chemistry and the textile industry. The result is a pigment model that spans a continuum from the very wet to the very dry brush stroke effects. We also propose a new pigment mixing method based on machine learning techniques to emulate pigment mixing in real life as well as to support the creation of new artificial pigments. To experiment with the proposed model, we embedded the model in a sophisticated digital brush system. The combined system exhibits interactive speed on a modest PC platform. http://www.cs.hku.hk/~songhua/pigment provides supplementary materials for this paper. 相似文献
948.
The results of processing the experimental drain-gate characteristics of test MOS transistors after irradiation with fast electrons and subsequent heat treatment are reported. It is shown that the concentration of trapping centers in the oxide is lowered as a result of radiation-thermal treatment. 相似文献
949.
G. Sh. Tsitsiashvili 《Automation and Remote Control》2007,68(7):1177-1185
Consideration was given to the parametric and structural optimization of the throughput of various queuing systems. Solutions of these problems rely on a combination of the decomposition methods for optimization of the nonsmooth functions and search of the admissible solutions of the transportation problem, as well as on the majorant estimates of the efficiency of the integrated queuing systems. 相似文献
950.
Stability-optimal solutions were established for the problem of control of the aperiodic, delay, and oscillatory plants approximated by the dynamic models representing a serial connection of the inertial units, inertial delay unit, and inertial units with oscillatory unit. 相似文献