scholarly journals Two-dimensional Placement Using Tabu Search

VLSI Design ◽  
2001 ◽  
Vol 12 (1) ◽  
pp. 13-23
Author(s):  
John M. Emmert ◽  
Dinesh K. Bhatia

Search based placement of modules is an important problem in VLSI design. It is always desired that the search should converge quickly to a high quality solution. This paper presents a tabu search based optimization technique to place modules on a regular two-dimensional array. The goal of the technique is to speed up the placement process. The technique is based on a two-step placement strategy. The first step is targeted toward improving circuit routability and the second step addresses circuit performance. The technique is demonstrated through placement of several benchmark circuits on academic as well as commercial FPGAs. Results are compared to placements generated by commercial CAE tools and published simulated annealing based techniques. The tabu search technique compares favorably to published simulated annealing based techniques, and it demonstrates an average execution time speedup of 20 with no impact on quality of results when compared to commercial tools.

VLSI Design ◽  
2000 ◽  
Vol 11 (3) ◽  
pp. 259-283 ◽  
Author(s):  
Shawki Areibi ◽  
Anthony Vannelli

The main goal of the paper is to explore the effectiveness of a new method called Tabu Search [1] on partitioning and compare it with two techniques widely used in CAD tools for circuit partitioning i.e., Sanchis Interchange method and Simulated Annealing, in terms of the running time and quality of solution. The proposed method integrates the well known iterative multi-way interchange method with Tabu Search and leads to a very powerful network partitioning heuristic. It is characterized by an ability to escape local optima which usually cause simple descent algorithms to terminate by using a short term memory of recent solutions. Moreover, Tabu Search permits backtracking to previous solutions, which explore different directions and generates better partitions.The quality of the test results on MCNC benchmark circuits are very promising in most cases. Tabu Search yields netlist partitions that contain 20%–67% fewer cut nets and are generated 2/3 to (1/2) times faster than the best netlist partitions obtained by using an interchange method. Comparable partitions to those obtained by Simulated Annealing are obtained 5 to 20 times faster.


Author(s):  
Fangyan Dong ◽  
◽  
Kewei Chen ◽  
Kaoru Hirota ◽  

A concept of neighborhood degree is proposed to evaluate the quality of solutions to scheduling problems such as vehicle routing, scheduling, and dispatching problems. It is possible to apply it to the optimization process of scheduling problems in order to switch between various optimization methods by considering convergence speed and solution quality. In the experiments on TSP benchmark data, two optimization methods, i.e., tabu search and simulated annealing, are switched effectively by observing the variation of the neighborhood degree. Directions for Practical applications are also mentioned.


Author(s):  
Hari Mohan Pandey

The term “appropriate parameters” signifies the correct choice of values has considerable effect on the performance that directs the search process towards the global optima. The performance typically is measured considering both quality of the results obtained and time requires in finding them. A genetic algorithm is a search and optimization technique, whose performance largely depends on various factors – if not tuned appropriately, difficult to get global optima. This paper describes the applicability of orthogonal array and Taguchi approach in tuning the genetic algorithm parameters. The domain of inquiry is grammatical inference has a wide range of applications. The optimal conditions were obtained corresponding to performance and the quality of results with reduced cost and variability. The primary objective of conducting this study is to identify the appropriate parameter setting by which overall performance and quality of results can be enhanced. In addition, a systematic discussion presented will be helpful for researchers in conducting parameters quantification for other algorithms.


Foods ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 876
Author(s):  
Olga Vyviurska ◽  
Nemanja Koljančić ◽  
Ha Anh Thai ◽  
Roman Gorovenko ◽  
Ivan Špánik

The enantiomeric ratio of chiral compounds is known as a useful tool to estimate wine quality as well as observe an influence of wine-producing technology. The incorporation of flow-modulated comprehensive two-dimensional gas chromatography in this type of analysis provides a possibility to improve the quality of results due to the enhancement of separation capacity and resolution. In this study, flow-modulated comprehensive two-dimensional gas chromatography was incorporated in enantioselective analysis to determine the influence of winemaking technology on specific features of botrytized wines. The samples included Tokaj essences (high-sugar wines), Tokaj botrytized wines and varietal wines (Furmint, Muscat Lunel, Lipovina) and wines maturated on grape peels. The obtained data was processed with hierarchic cluster analysis to reveal variations in composition and assess classification ability for botrytized wines. A significant difference between the samples was observed for the enantiomeric distribution of ethyl lactate and presence of monoterpene alcohols. The varietal wines were successfully separated from the other types, which showed more similar results and could be divided with additional parameters. We observed a correlation between the botrytized wines and the varietal wines fermented with grape skins. As to the essences produced from juice of botrytized grapes, the results were quite similar to those of the botrytized wines, even though monoterpenes were not detected in the extracts.


Author(s):  
Russell L. Steere ◽  
Eric F. Erbe ◽  
J. Michael Moseley

We have designed and built an electronic device which compares the resistance of a defined area of vacuum evaporated material with a variable resistor. When the two resistances are matched, the device automatically disconnects the primary side of the substrate transformer and stops further evaporation.This approach to controlled evaporation in conjunction with the modified guns and evaporation source permits reliably reproducible multiple Pt shadow films from a single Pt wrapped carbon point source. The reproducibility from consecutive C point sources is also reliable. Furthermore, the device we have developed permits us to select a predetermined resistance so that low contrast high-resolution shadows, heavy high contrast shadows, or any grade in between can be selected at will. The reproducibility and quality of results are demonstrated in Figures 1-4 which represent evaporations at various settings of the variable resistor.


2018 ◽  
Vol 26 (2) ◽  
pp. 131-143
Author(s):  
Marlinawati Marlinawati ◽  
Dewi Kusuma Wardani

The purpose of this research is to know the influence between the Quality of Human Resources, Utilization of Information Technology and Internal Control System Against Timeliness of Village Government Financial Reporting at Gunungkidul Regency. This research is causative research. The population is the village government in Gunungkidul Regency, especially in Gedangsari subdistrict. Criteria of respondents in the study were to village and village apparatus. We use questionnaire to collect data. We use multiple regression with SPSS program version 16.0 to analyze data. We find that quality of human resources and internal control system have a positive influence on the timeliness of village government financial reporting. On the other hand, utilization of information technology does not influence the timeliness of village government financial reporting. These imply that the quality of human resources and internal control system can speed up the preparation of village government financial reporting.


2016 ◽  
pp. 141-149
Author(s):  
S.V. Yershov ◽  
◽  
R.М. Ponomarenko ◽  

Parallel tiered and dynamic models of the fuzzy inference in expert-diagnostic software systems are considered, which knowledge bases are based on fuzzy rules. Tiered parallel and dynamic fuzzy inference procedures are developed that allow speed up of computations in the software system for evaluating the quality of scientific papers. Evaluations of the effectiveness of parallel tiered and dynamic schemes of computations are constructed with complex dependency graph between blocks of fuzzy Takagi – Sugeno rules. Comparative characteristic of the efficacy of parallel-stacked and dynamic models is carried out.


Author(s):  
Adi Mora Lubis ◽  
Nelly Astuti Hasibuan ◽  
Imam Saputra

Digital imagery is a two-dimensional image process through a digital computer that is used to manipulate and modify images in various ways. Photos are examples of two-dimensional images that can be processed easily. Each photo in the form of a digital image can be processed through a specific software. In the water environment, the light factor greatly influences the results of the quality of the image obtained. With the deepening of underwater shooting, the results obtained will be the darker the quality of the underwater image. . uneven lighting and bluish tones. One of the factors that influence the recognition results in pattern recognition is the quality of the image that is inputted. The image acquired from the source does not always have good quality. The process of repairing digital images that experience interference in lighting. The lighting repair process uses homomorphic filtering and uses contrast striching and will compare the quality of both methods and test to prove the results of image quality between homomorphic filtering and contrast streching. Until later the results of both methods can be seen which is better. homomorphic filtering and contrast stretching can produce image improvements with pretty good performance.Keywords: Digital Image, Underwater Image, Homomorphic Filtering, Contrast Streching, Matlab R2010a


Author(s):  
Bainun Harahap

Digital imagery is a two-dimensional image process through a digital computer that is used to manipulate and modify images in various ways. Photos are examples of two-dimensional images that can be processed easily. Each photo in the form of a digital image can be processed through certain software devices. In the water environment, light factors greatly influence the results of image quality obtained. With the deepening of underwater shooting, the results obtained will be the darker the quality of the underwater image. Underwater imagery is widely used as an object in various activities such as underwater habitat mapping, underwater environment monitoring, underwater object search. Uneven lighting and colors that tend to be bluish and runny. One of the factors that influence the recognition results in pattern recognition is the quality of the image that is inputted. The image acquired from the source does not always have good quality. The process of improvement in digital images that experience interference in lighting and exposure to sunlight. The lighting repair process uses the retinex method and will compare the quality of the two methods later. Until later the results of both methods can be seen which is better. Retinex method can produce image improvement with high performance.Keywords: Digital Cintra, Underwater, Matlab Retinex Method


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