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81.
最优控制在软基预压加固分析与计算中的应用 总被引:1,自引:1,他引:0
软土地基通过打砂井后压载固结,提高其承载力,是在修建机场、高速公路、堤坝、码头以及货场等工程中广泛采用的方法。本文给出容许承载力的计算公式、稳定性条件、打砂井压载固结适用范围、最小压载时间计算以及提出最优分级加载方案,给出基于Mathcad可视化计算程序,对工程进行分析计算,并对施工进行实时控制。 相似文献
82.
In this paper, we investigate the applicability of graph cuts to the SFS (shape-from-shading) problem. We propose a new semi-global method for SFS using graph cuts. The new algorithm combines the local method proposed by Lee and Rosenfeld [C.H. Lee, A. Rosenfeld, Improved methods of estimating shape from shading using the light source coordinate system, Artif. Intell. 26 (1985) 125-143] and a global method using an energy minimization technique. By employing a new global energy minimization formulation, the convex/concave ambiguity problem of Lee and Rosenfeld's method can be resolved efficiently. A new combinatorial optimization technique, the graph cuts method, is used for the minimization of the proposed energy functional. Experimental results on a variety of synthetic and real-world images show that the proposed algorithm reconstructs the 3-D shape of objects very efficiently. 相似文献
83.
Sharp GC Lee SW Wehe DK 《IEEE transactions on pattern analysis and machine intelligence》2008,30(1):120-130
Missing data are common in range images, due to geometric occlusions, limitations in the sensor field of view, poor reflectivity, depth discontinuities, and cast shadows. Using registration to align these data often fails, because points without valid correspondences can be incorrectly matched. This paper presents a maximum likelihood method for registration of scenes with unmatched or missing data. Using ray casting, correspondences are formed between valid and missing points in each view. These correspondences are used to classify points by their visibility properties, including occlusions, field of view, and shadow regions. The likelihood of each point match is then determined using statistical properties of the sensor, such as noise and outlier distributions. Experiments demonstrate a high rates of convergence on complex scenes with varying degrees of overlap. 相似文献
84.
Sang Boem Lim Hanku Lee Bryan Carpenter Geoffrey Fox 《The Journal of supercomputing》2008,43(2):165-182
The paper research is concerned with enabling parallel, high-performance computation—in particular development of scientific
software in the network-aware programming language, Java. Traditionally, this kind of computing was done in Fortran. Arguably,
Fortran is becoming a marginalized language, with limited economic incentive for vendors to produce modern development environments,
optimizing compilers for new hardware, or other kinds of associated software expected of by today’s programmers. Hence, Java
looks like a very promising alternative for the future.
The paper will discuss in detail a particular environment called HPJava. HPJava is the environment for parallel programming—especially data-parallel scientific programming—in Java. Our HPJava is
based around a small set of language extensions designed to support parallel computation with distributed arrays, plus a set
of communication libraries. A high-level communication API, Adlib, is developed as an application level communication library suitable for our HPJava. This communication library supports
collective operations on distributed arrays. We include Java Object as one of the Adlib communication data types. So we fully support communication of intrinsic Java types, including primitive
types, and Java object types. 相似文献
85.
Hyun Sup Lee Tai Hun Kwon Jong Hyun Kim Suk Sang Chang 《Microsystem Technologies》2008,14(8):1149-1155
The present study proposes a simple method to replicate nano/micro combined multiscale structures using an intermediate film
mold and anodic aluminum oxide (AAO) nanomold in hot embossing process. The proposed method is simply to add an intermediate
film mold with microscale thru-hole patterns to the ordinary mold system, on which nanostructures are patterned, in the hot
embossing process. The intermediate film mold is inserted between polymer substrate and AAO nanomold. During the hot embossing
process, the polymer first fills microscale thru-hole patterns in the intermediate film mold and subsequently fills nanopores
in AAO nanomold, resulting in the nano/micro combined structures. The intermediate film molds, which have microscale thru-hole
patterns were fabricated by micro-milling, laser ablation, etching methods and/or LIGA process. The nano/micro combined structures
were successfully replicated by the proposed method. 相似文献
86.
Hyun‐Sang Park Seon‐Beom Ji Min‐Koo Han Jae‐Sic Lee Chi‐Woo Kim Kwang‐Soo Choi 《Journal of the Society for Information Display》2009,17(8):681-686
Abstract— A new digital ambient‐light sensor system is presented which employs two linear light sensors with different sensitivities and automatically adjusts the sensitivity based on the illumination condition. The adaptation mechanism allows a very wide range of light intensity to be detected, and the input dynamic range of the system is substantially improved from 22.5 to 45.1 dB. The proposed method does not require any additional precision bits for output data. Due to the small number of the output bits and the simple conversion process, the system can be easily integrated on the display panel. 相似文献
87.
Bong Hyun You Byoung Jun Lee Sang Youn Han Seiki Takahashi Brian H. Berkeley Nam Deog Kim Sang Soo Kim 《Journal of the Society for Information Display》2009,17(2):87-94
Abstract— A touch‐screen‐panel (TSP) embedded 12.1‐in. LCD employing a standard existing a‐Si:H TFT‐LCD process has been successfully developed. Compared with conventional external touch‐screen panels, which use additional components to detect touch events, the new internal TSP exhibits a clearer image and improved touch feeling, as well as increased sensing speed using discrete sensing lines to enable higher‐speed sensing functions including handwriting. The new internal digital switching TSP can be fabricated with low cost because it does not require any additional process steps compared to a standard a‐Si:H TFT‐LCD. 相似文献
88.
Investigation of viscosity effect on droplet formation in T-shaped microchannels by numerical and analytical methods 总被引:1,自引:1,他引:0
Both numerical and analytical models have been developed to explore the viscosity effect of the continuous phase on drop formation
at a T-shaped junction in immiscible liquids. The effects of the generalized power law coefficient, the power law exponent
and the yield stress on the mechanism of drop breakup, final drop size and frequency of drop formation are studied by using
the numerical three-dimensional volume of fluid model. Droplets coalescence in Bingham fluids is observed in the beginning
transient period. The effect of yield stress on drop extension is also discussed. Predictions of drop size by using an analytical
force balance show satisfactory agreement with simulation results for Newtonian and power law fluids with different viscosity
ratios. The approximation error associated with the analytical model for Bingham fluids is also acceptable. This analytical
model can greatly shorten the prediction time as compared with the numerical model, which is helpful for on-line control. 相似文献
89.
Devinder Thapa Chang Mok Park Sang C. Park Gi-Nam Wang 《International Journal of Control, Automation and Systems》2009,7(2):165-174
The objective of this paper is to reduce the development time of a PLC (Programmable Logic Controller) by automating the task
of code generation. For this purpose, we applied t-MPSG (Timed-Message Based Part State Graph). The t-MPSG is an extended finite state automata used to model and generate an execution module for a real-time shop floor controller
system. In our proposed method, t-MPSG is used to model the formal specification of the controller system that can be translated into textual structure. After
the verification of the t-MPSG model, it can be used as an input to the plc-builder tool. The plc-builder tool is an extended version of a conventional MPSG simulator. It can be used to translate the textual structure of
the t-MPSG into an IEC standard PLC code. Finally, the generated code can be downloaded to a PLC emulator or a PLC device for the
purpose of simulation and execution. The similarity in the hierarchical structure of the t-MPSG and the IEC standard PLC program has made it convenient to transform from one form to another. Furthermore, an illustration
of the methodology to auto-generate IEC standard PLC code using t-MPSG is explained with a suitable example.
Recommended by Editorial Board member Young Soo Suh under the direction of Editor Jae Weon Choi. This work was partially supported
by Defense Acquisition Program Administration and Agency for Defense Development under the contract (UD080042AD).
Devinder Thapa is a Postdoc Research Fellow in the Department of Industrial & information systems at Ajou University, Korea. He completed
his Ph.D. from Ajou University in Industrial and Information Systems Engineering. His area of research is related to manufacturing
automation and intelligent decision support systems.
Chang Mok Park is a Professor in the Department of Technology & Systems Management at Induk Institute of Technology. He completed his Ph.D.
in 2002 from Ajou University in Industrial Engineering. His research interest is related to manufacturing optimization, discrete
event system simulation and signal analysis.
Sang C. Park is an Associate Professor in the Department of Industrial & Information Systems Engineering at Ajou University. He received
his B.S., M.S., and Ph.D. degrees from KAIST in 1994, 1996, and 2000, respectively, all in Industrial Engineering. His research
interests include geometric algorithms in CAD/CAM, process planning, engineering knowledge management, and discrete event
system simulation.
Gi-Nam Wang is the Head and a Professor in the Department of Industrial & Information Systems Engineering at Ajou University, Korea.
He completed his Ph.D. in 1992 from Texas A&M University, in Industrial Engineering. He has worked as Visiting Professor at
University of Texas at Austin during 2000–2001. His area of research is related to Intelligent Information & manufacturing
systems, system integration & automation, e-Business solutions and image processing. 相似文献
90.
3-D manipulation of millimeter- and micro-sized objects using an acoustically excited oscillating bubble 总被引:1,自引:1,他引:0
This communication describes novel 3-D manipulations of objects using an acoustically excited oscillating bubble deposited
on a hydrophobic rod tip. The oscillating bubble captures various millimeter- and micron-sized neighboring objects including
glass and polystyrene beads (~100 μm), fish egg, and live water flea (~1 mm). The captured objects are carried in a 3-D space
by traversing the bubble tip, and released at desired positions by simply turning off the oscillation. Carrying performance
is characterized along with high-speed imaging of oscillating bubbles by varying the frequency and amplitude of the acoustic
excitation and the carrying speed. The higher the oscillation amplitude, the higher the carrying efficiency. The maximum carrying
speed is measured at over 3 mm/s. This method is effective with a low-level acoustic excitation (bubble oscillation amplitude
relative to the diameter ≤5%), possibly providing a cost-effective, soft-contact manipulating tool for handling biological
objects. 相似文献