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排序方式: 共有413条查询结果,搜索用时 15 毫秒
101.
Recently, many methods have been proposed for constructing gene regulatory networks (GRNs). However, most of the existing methods ignored the time delay regulatory relation in the GRN predictions. In this paper, we propose a hybrid method, termed GA/PSO with DTW, to construct GRNs from microarray datasets. The proposed method uses test of correlation coefficient and the dynamic time warping (DTW) algorithm to determine the existence of a time delay relation between two genes. In addition, it uses the particle swarm optimization (PSO) to find thresholds for discretizing the microarray dataset. Based on the discretized microarray dataset and the predicted types of regulatory relations among genes, the proposed method uses a genetic algorithm to generate a set of candidate GRNs from which the predicted GRN is constructed. Three real-life sub-networks of yeast are used to verify the performance of the proposed method. The experimental results show that the GA/PSO with DTW is better than the other existing methods in terms of predicting sensitivity and specificity. 相似文献
102.
Ioana Leu?tean 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2012,16(11):1845-1850
We introduce the MV-seminorms and we prove Hahn–Banach type extension results for linear functions and MV-algebra homomorphisms dominated by MV-seminorms. 相似文献
103.
The status and activity of technological development in the field of biofuel and biohydrogen energy from the year 2000–2011 were investigated utilizing patent bibliometric analysis. Based on the reports, the current status indicates that the key technologies for biofuel energy have reached technological maturity in the United States. However, the principal or predominant technologies for biohydrogen energy need a great deal of work to accelerate the development of biohydrogen technology. In addition, three important subjects were found from citation techniques, which are related to biodiesel fuel, biological fuel cell, and the biohydrogen. These patents described that the focus of key techniques of energy production should be established towards low energy demand technologies, and biohydrogen was found to be a potential candidate of the future. Finally, this proposed model can be applied to all high-technology cases, and particularly to green energy field. 相似文献
104.
Thien Khanh Tran Namkeun Kim Hoang Jyh Leu Minh Phuc Pham Nhat Anh Luong Hoang Khiem Vo 《International Journal of Hydrogen Energy》2021,46(27):13976-13984
In this study, the generation of hydrogen from synthesis gas through the pyrolysis of modified Water Hyacinth (Eichhornia Crassipes) biomass was investigated. The modified Water Hyacinth feedstocks were prepared by immersing its dried samples into Iron Chlorides (III) solution under different concentrations (0.5, 1, 1.5, and 2 M). After a 60 min pyrolysis at 540 °C, each created biochar sample also generates a different volume of synthesis gas depending on the properties of the feedstock that were applied to the system. In that manner, it is clear that the value of ferric chloride concentration plays an important role in the generating of synthesis gas. The study indicates that the increase of ferric chloride concentration may also raise the production of synthesis gas, and the amount of hydrogen as well. The result indicates that the 2WH sample (with 2 M of ferric chloride catalyst) exhibited the highest conversion for Water Hyacinth pyrolysis volatiles, with 280 mL of total gas production (42% of hydrogen included, 23% of carbon dioxide, 22% of carbon monoxide and 7% of methane). Therefore, the main objective of the work is achieved by revealing the influence of the metal catalyst over the production of gases via the pyrolysis. On the other hand, the fact that the Water Hyacinth can be utilized effectively also contributes greatly to the matter of environmental betterment. 相似文献
105.
Simultaneous assessment of sources, processes, and factors influencing herbicide losses to surface waters in a small agricultural catchment 总被引:1,自引:0,他引:1
Leu C Singer H Stamm C Müller SR Schwarzenbach RP 《Environmental science & technology》2004,38(14):3827-3834
To take appropriate measures to minimize agricultural herbicide inputs into surface waters, detailed knowledge is required about all the factors that control the losses of a given compound from point sources (i.e., farmyards) as well as from the diffuse sources (i.e., the fields) within a given catchment. In this and in a companion paper, we present the results of a comprehensive field study, in which the temporal and spatial variability of the losses of three herbicides (atrazine, dimethenamid, and metolachlor) into the surface waters within a small catchment (2.1 km2) were investigated on different scales (i.e., field scale to whole catchment) after a controlled application of the compounds. In this paper, we discuss the loss dynamics of the three herbicides (and some of their metabolites) from the whole catchment over a period of 67 d after application. An identical mixture of the three herbicides was applied on 13 cornfields within 12 h, allowing for a comparison of their losses under identical meteorological conditions. Thanks to a high temporal sampling resolution, it was possible to distinguish between losses from a farmyard and losses from the fields. Farmyard losses contributed less than 20% to the total loads but caused the highest concentrations. The major herbicide losses from the agricultural fields occurred during the first two rain events after application that led to significant surface runoff and preferential flow into tile drains. In the soils of all fields, dimethenamid declined somewhat faster than atrazine and metolachlor, whereas atrazine was mobilized most effectively to runoff water. Relative losses of the three compounds did not vary by more than a factor of 3 (0.82, 0.27, and 0.41% of the mass applied for atrazine, dimethenamid, and metolachlor, respectively). Highest peak concentrations at the outlet of the catchment were found for atrazine (i.e., approximately 8 microg L(-1) for a short period (<2 h) due to point source losses and between 1 and 3.5 microg L(-1) during more than 24 h due to diffuse losses). 相似文献
106.
The Sr0.6Ba0.4Nb2O6 (SBN) thin films were successfully prepared on Pt/Ti/Si and SiO2/Si/Al substrates and crystallized subsequently using rapid thermal annealing (RTA) process in ambient atmosphere for 1 min. The surface morphologies and thicknesses of as-deposited and annealed SBN thin films were characterized by field emission scanning electron microscopy, and the thickness was about 246 nm. As compared with the as-deposited SBN thin films, the RTA-treated process had improved the crystalline structures and also had large influence on the crystalline orientation. When the annealing temperatures increased from 700 degrees C to 900 degrees C, the diffraction intensities of (410) and (001) peaks apparently increased. Annealed at 900 degrees C, the (001) peak had the maximum texture coefficient and SBN thin films showed a highly c-axis (001) orientation. The influences of different RTA-treated temperatures on the polarization-applied electric field (P-E) curves and the capacitance-voltage (C-V) curves were also investigated. 相似文献
107.
Jenn-Sen Leu Papamarcou A. 《IEEE transactions on information theory / Professional Technical Group on Information Theory》1999,45(2):572-585
Two distributed systems are considered for discriminating between two finite-alphabet bivariate memoryless sources and for detecting a known signal in stationary bivariate additive Gaussian noise. Each system comprises two sensors, M-ary local quantizers and a fusion center which makes decisions based on quantized source observations. The problem of asymptotically optimal quantization is considered in detail for the binary (M=2) case. It is shown that optimality is achieved by quantizing a locally computed likelihood ratio wherein one distribution is in general different from the appropriate source marginal. For the problem of detection in Gaussian noise, it is further demonstrated that the optimal distributed system attains the same asymptotic performance as the optimal centralized system for appropriate choice of M 相似文献
108.
Minority-carrier electron lifetime, mobility and diffusion length in heavily doped p-type Si were measured at 296 and 77 K. It was found that a 296 K μn (pSi)≈μn (nSi) for N AA≲5×1018 cm-3, while μn (pSi)/μn (nSi)≈1 to 2.7 for higher dopings. The results also show that for N AA≲3×1019 cm-3, D (pSi) at 77 K is smaller than that at 296 K, while for higher dopings D n (pSi) is larger at 77 K than at 296 K. μn (pSi) at 77 K increases with the increasing doping above N AA>3×1018 cm-3, in contrast to the opposite dependence for μn (nSi) in n+ Si 相似文献
109.
This paper develops an optimal allocation procedure for the disassembled components of electronic equipment. It also reviews and discusses the reuse options available to high-tech companies when it comes to disassembly. A piecewise linear concave program is formulated to find the optimal disassembly strategy. The model is then applied to actual data from an electronics manufacturer. It is concluded that the landfill option, the most undesirable option available to most manufacturers, can be avoided if the manufacturer can find other options with non-negative returns. 相似文献
110.
Po‐Jen Hsiao Ming‐Hsien Tsai Jyh‐Gang Leu Yu‐Wei Fang 《Hemodialysis international. International Symposium on Home Hemodialysis》2015,19(2):330-332
Iliopsoas abscess is a rare complication in hemodialysis patients that is mainly due to adjacent catheterization, local acupuncture, discitis, and bacteremia. Herein, we report a 47‐year‐old woman undergoing regular hemodialysis via a catheter in the internal jugular vein who presented with low back pain and dyspnea. A heart murmur suggested the presence of catheter‐related endocarditis, and this was confirmed by an echocardiogram and a blood culture of methicillin‐resistant Staphylococcus aureus. A computed tomography indicated a pulmonary embolism and an incidental finding of iliopsoas abscess. Following surgical intervention and intravenous daptomycin, the patient experienced full recovery and a return to usual activities. This case indicates that an iliopsoas abscess can be related to a jugular vein catheter, which is apparently facilitated by infective endocarditis. The possibility of iliopsoas abscess should be considered when a hemodialysis patient presents with severe low back pain, even when there is no history of adjacent mechanical intervention. 相似文献