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1.
Towards cognitive evaluation of computer-drawn sketches 总被引:1,自引:0,他引:1
This paper seeks to raise visual comparisons beyond subjective opinions into evidence-based visual reasoning. It provides
an informal deductive analysis of the marks in sketches derived with two competing line-filtering algorithms. This prompted
the novel speculation that the visual system might be placing some types of anomalies in the foreground of mental 3D space,
where they can be ignored. A brief survey is provided to encourage informed debate. Although the proposed cognitive computation
was not automated, it justified the rejection of the Douglas–Peucker algorithm in favour of Visvalingam's algorithm in subsequent
research within the Cartographic Information Systems Research Group (CISRG). 相似文献
2.
The Douglas-Peucker Algorithm for Line Simplification: Re-evaluation through Visualization 总被引:3,自引:0,他引:3
The primary aim of this paper is to illustrate the value of visualization in cartography and to indicate that tools for the generation and manipulation of realistic images are of limited value within this application. This paper demonstrates the value of visualization within one problem in cartography, namely the generalisation of lines. It reports on the evaluation of the Douglas-Peucker algorithm for line simplification. Visualization of the simplification process and of the results suggest that the mathematical measures of performance proposed by some other researchers are inappropriate, misleading and questionable. 相似文献
3.
Govindaraj Magudeeswaran Visvalingam Balasubramanian S. Sathyanarayanan Gankidi Madhusudhan Reddy A. Moitra S. Venugopal G. Sasikala 《Metals and Materials International》2009,15(6):1017-1026
Austenitic stainless steel, low hydrogen ferritic steel and high nickel steel consumables are used for the welding of armor-grade
quenched and tempered (Q&T) steels. The use of such consumables in the welding of armorgrade Q&T steel leads to the formation
of distinct microstructures in the respective welds and has a major influence on the dynamic fracture toughness. Hence, this
paper examines how shielded metal arc welding consumables affect the dynamic fracture toughness (J1d) of armor-grade Q&T steel joints. The J1d values of joints fabricated with high nickel steel joints are superior than all other joints. 相似文献
4.
The viabilities of cells in cultures of Escherichia coli growing with formation of filaments at 6 °C
Cold adapted, exponential phase cells of three strains of Escherichia coli were incubated at 6 °C for 10 days. Cells in all cultures grew by elongation, with formation of filaments to different extents, but with generally only small changes in the numbers of colony forming units (cfu). At later incubation times some cells of all lengths were identified as dead by LIVE/DEAD staining, with cell wall damage being apparent in some cells stained as dead but not in cells stained as live. When samples of cultures were incubated at 37 °C for 2h, the numbers of cfu of two strains (ATCC 11775 and ATCC 23739) increased similarly and were not affected by the time of prior exposure to 6 °C. When incubated at 37 °C, the numbers of cfu of the other strain (8WT) increased less after incubation at 6 °C for 1, 2 or 3 days than when transferred to 37 °C from 15 °C. After>3 days at 6 °C numbers of strain 8WT were reduced after incubation at 37 °C for 2h. The findings show that in cultures of E. coli elongating at 6 °C, elongating cells and filaments do not divide; and cells of all lengths lose viability at similar rates. Also, the findings indicate that substantial fractions of cells in cultures elongating at refrigerator temperatures are inactivated by an abrupt change of temperature to 37°C. 相似文献
5.
Arulsamy Arun Negemiya Selvarajan Rajakumar Visvalingam Balasubramanian 《Microscopy research and technique》2020,83(3):318-328
Welding of dissimilar metals is challenging because of the formation of microfissuring, strain age cracking and brittle intermetallic compounds. The above‐said problems can be avoided by controlled heating and cooling rates and the formation of beneficial intermetallic layers in the joint interface using solid‐state welding techniques such as diffusion bonding. This study investigates, the effect of diffusion bonding process parameters of dissimilar metals (AISI 410 martensitic stainless steel and nickel [Su 718] based superalloy). Fifteen joints were fabricated using different levels of bonding temperature (920–1,000°C), bonding pressure (10–18 MPa) and holding time (30–90 min). From this investigation, it is identified that joints fabricated at bonding temperature 980°C, bonding pressure 16 MPa and holding time 75 min yielded an extreme tensile strength (263 MPa) and hardness (450 HV) compared to the other joints. The tensile properties of the welded joints were assessed and associated with the microstructures. Optical Microscopy (OM), Scanning Electron Microscopy (SEM) and X‐Ray Diffraction (XRD) analysis were used to estimate the metallurgical characteristics of the weldment. The EDS examination was supported out to analyses the interface composition and to decide the composition at the interface. Furthermore, a lot of δ phase precipitates were likewise found in the bonded region. 相似文献
6.
M. Visvalingam 《Software》1976,6(3):397-403
The paper describes the coded delta scheme, which is one of the methods used by the Census Research Unit, University of Durham, for compacting the 1971 U.K. census data. It evaluates the merits and limitations of the technique in relation to the characteristics of the data set and other techniques available for compact encoding of numeric and string data. 相似文献
7.
Anti-mutagenic Properties of Mono- and Dienoic Acid Biohydrogenation Products from Beef Fat 下载免费PDF全文
Jeyachchandran?Visvalingam Payam?Vahmani David?C.?Rolland Michael?E.?R.?Dugan Xianqin?YangEmail author 《Lipids》2017,52(7):651-655
Unsaturated fatty acid biohydrogenation products from beef fat and pure fatty acids were subjected to the Ames Salmonella mutagenicity testing, including monounsaturated fatty acids [MUFA: oleic acid, vaccenic acid, elaidic acid; beef fatty acid fractions rich in trans (t)11/t13‐t14‐18:1 (t11,13,14‐Frac), t10‐18:1 (t10‐Frac)] and dienoic fatty acids [linoleic acid, conjugated linoleic isomers cis (c)9,t11‐18:2 and t10,c12‐18:2, and a mixed beef dienoic fatty acid fraction high in c9,t13‐/t8,c12/t11c15‐18:2 (MD)]. Significantly higher anti‐mutagenic effects of oleic acid, vaccenic acid, t11, 13, 14‐Frac, and t10‐Frac against daunomycin were observed at 2.5 mg. All dienoic acids except MD significantly reduced daunomycin mutagenicity at ≥0.25 mg. Anti‐mutagenicity of oleic and vaccenic acids against 2‐aminoanthracene was found at 2.5 and 0.25 mg, respectively. All dienoic acids significantly reduced 2‐aminoanthracene mutagenicity at ≥0.25 mg. Findings of this study show that unsaturated fatty acids, including trans‐fatty acids commonly found in beef, can act as strong anti‐mutagens. 相似文献
8.
Cells in log phase cultures of Escherichia coli ATCC 23739 and E. coli O157:H7 02:0627 incubated at 6 °C for 8 days grew by elongation and the formation of filaments. When suspensions of cells from the cultures were incubated at 37 °C for 4 h, there was little or no change in mean cell lengths during the first hour of incubation; but subsequently the fractions of elongated (>4 ≤ 10 μm) or filamentous (>10 μm) cells declined with the most cells being of normal size (≤4 μm) after 3 h. LIVE/DEAD BacLight staining indicated that ≥94% of cells were alive after all times at 37 °C. Direct observation of cells on slides incubated at 37 °C, from culture incubated at 6 °C for 5 days, showed that few or no cells of normal size divided. Elongated cells of both strains, and filamentous cells of E. coli ATCC 23739 divided to multiple daughter cells; but filamentous cells of E. coli O157:H7 lysed. The results indicate that abrupt shifts of log phase E. coli from refrigeration to warm temperatures lead to inactivation of some cells and division of others to multiple daughter cells, and suggest that the extents of these opposing responses may vary widely among strains. 相似文献
9.
Shelf-life of minimally processed cabbage treated with neutral electrolysed oxidising water and stored under equilibrium modified atmosphere 总被引:2,自引:0,他引:2
Gómez-López VM Ragaert P Ryckeboer J Jeyachchandran V Debevere J Devlieghere F 《International journal of food microbiology》2007,117(1):91-98
Minimally processed vegetables (MPV) have a short shelf-life. Neutral electrolysed oxidising water (NEW) is a novel decontamination method. The objective of this study was to test the potential of NEW to extend the shelf-life of a MPV, namely shredded cabbage. Samples of shredded cabbage were immersed in NEW containing 40 mg/L of free chlorine or tap water (control) up to 5 min, and then stored under equilibrium modified atmosphere at 4 degrees C and 7 degrees C. Proliferation of aerobic mesophilic bacteria, psychrotrophic bacteria, lactic acid bacteria and yeasts were studied during the shelf-life. Also pH and sensorial quality of the samples as well as O(2) and CO(2) composition of the headspace of the bags was evaluated. From the microbial groups, only psychrotrophic counts decreased significantly (P<0.05) due to the effect of NEW, but the counts in treated samples and controls were similar after 3 days of storage at 4 degrees C and 7 degrees C. Packaging configurations kept O(2) concentration around 5% and prevented CO(2) accumulation. pH increased from 6.1-6.2 to 6.4 during the shelf-life. No microbial parameter reached unacceptable counts after 14 days at 4 degrees C and 8 days of storage at 7 degrees C. The shelf-life of controls stored at 4 degrees C was limited to 9 days by overall visual quality (OVQ), while samples treated with NEW remained acceptable during the 14 days of the experiment. The shelf-life of controls stored at 7 degrees C was limited to 6 days by OVQ and browning, while that of samples treated with NEW were limited to 9 days by OVQ, browning and dryness. According to these results, a shelf-life extension of at least 5 days and 3 days in samples stored respectively at 4 degrees C and 7 degrees C can be achieved by treating shredded cabbage with NEW. NEW seems to be a promising method to prolong the shelf-life of MPV. 相似文献
10.
Govindaraj Magudeeswaran Visvalingam Balasubramanian Gankidi Madhusudhan Reddy 《Metals and Materials International》2008,14(4):523-529
Quenched and tempered (Q&T) steels are prone to hydrogen induced cracking after welding. Austenitic stainless steel (ASS)
welding consumables are traditionally used for welding of high hardness, Q&T steels as they have higher solubility for hydrogen
in the austenitic phase. The use of stainless steel consumables for a non stainless steel base metal is not economical. Hence,
in the present work, an attempt was made to explore alternate consumables for welding Q&T steels. Flux cored arc welding process
was used to fabricate the joints using austenitic stainless steel and low hydrogen ferritic steel consumables. The joints
fabricated using low hydrogen ferritic steel consumables exhibited superior fatigue performances than the joints fabricated
using ASS consumables. 相似文献