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11.

When the drivers approaching signalized intersections (onset of yellow signal), the drivers would enter into a zone, where they will be in uncertain mode assessing their capabilities to stop or cross the intersection. Therefore, any improper decision might lead to a right-angle or back-end crash. To avoid a right-angle collision, drivers apply the harsh brakes to stop just before the signalized intersection. But this may lead to a back-end crash when the following driver encounters the former’s sudden stopping decision. This situation gets multifaceted when the traffic is heterogeneous, containing various types of vehicles. In order to reduce this issue, this study’s primary objective is to identify the driving behaviour at signalized intersections based on the driving features (parameters). The secondary objective is to classify the outcome of driving behaviour (safe stopping and unsafe stopping) at the signalized intersection using a support vector machine (SVM) technique. Turning moments are used to identify the zones and label them accordingly for further classification. The classification of 50 instances is identified for training and testing using a 70%–30% rule resulted in an accuracy of 85% and 86%, respectively. Classification performance is further verified by random sampling using five cross-validation and 30 iterations, which gave an accuracy of 97% and 100% for training and testing. These results demonstrate that the proposed approach can help develop a pre-warning system to alert the drivers approaching signalized intersections, thus reducing back-end crash and accidents.

  相似文献   
12.
Computing Profile Similarity is a fundamental requirement in the area of Social Networks to suggest similar social connections that have high chance of being accepted as actual connection. Representing and measuring similarity appropriately is a pursuit of many researchers. Cosine similarity is a widely used metric that is simple and effective. This paper provides analysis of cosine similarity for social profiles and proposes a novel method to compute Piecewise Maximal Similarity between profiles. The proposed metric is 6% more effective to measure similarity than cosine similarity based on computations on real data.  相似文献   
13.
Application of adequate level of K has shown to improve the competitive ability of the legume in legume/grass mixtures. However, the effect of K on the competitive ability of grain legumes in legume/cereal intercropping systems has not been adequately studied. Hence, studies were made to ascertain if the effects of K could be exploited in improving the performance of groundnut (Arachis hypogaea L.) cv. No. 45 when intercropped with maize (Zea mays L.) cv. Badra. The study was conducted at the Faculty of Agriculture, University of Ruhuna, Kamburupitiya, Sri Lanka in 1988 in basins filled with 36 kg of soil. It involved establishing maize and groundnut as monocrops and as intercrops at three K levels viz. 0, 20 and 40 mg of K kg–1 of soil. Monocrop maize and groundnut had 2 and 5 plants/basin, respectively while the intercrop had 1 maize plant and 3 groundnut plants/basin. The soil used was Red Yellow Podzolic which was tagged by incorporating15N-labelled plant material. When grown as a monocrop, K had no effect on the percent N derived from atmosphere, amount of N2 fixed, dry matter production, pod yield and total N content of groundnut. However, when intercropped with maize lack of K application affected the above parameters significantly which was overcome by improving K level. Thus, the optimum level of K for groundnut was greater when intercropped than monocropped. A significant interaction between K level and cropping system was evident with regard to N2 fixation, pod yield and total dry matter production of groundnut. Intercrop maize derived 30–35% of its N content from the associated groundnut plants which amounted to 13–22 mg N/plant. The amount of N supplied by groundnut to associated maize plant was not affected by K level. It appears that there is scope for alleviating growth depression of the legume component in legume/cereal intercropping systems by developing appropriate K fertilizer practices.  相似文献   
14.
The efficiency of using lactic acid (LA) as a surface decontaminator for carcasses contaminated with spinal chord (SC) tissues was evaluated. Four representative places with surface area of 5 × 5 cm, were marked on the inner side of the porcine carcasses. 0.200 μl of 0.5% SC solution was applied to each marked area and separately washed in a specially designed spraying cabinet, which comprises 15 nozzles adjusted to spray 1% LA or tap water with a scatter pressure of 0.49 MPa. Samples were collected after washing for 15, 30, 60 and 90 s and analyzed by Ridascreen kit ELISA test. 1% LA reduces the SC materials to pre-contaminated levels while having negligible effect on the color of carcasses. Furthermore washing with LA insignificantly reduced the total microbial counts. Using very low concentration of LA (1%) in production lines of slaughter houses may help to decontaminate the carcasses to some extent without having adverse impact on quality attributes.  相似文献   
15.
Infertility is a common feature of the human disorder ataxia-telangiectasia and Atm-deficient mice are completely infertile. To gain further insight into the role of ATM in meiosis, we examined meiotic cells in Atm-deficient mice during development. Spermatocyte degeneration begins between postnatal days 8 and 16.5, soon after entry into prophase I of meiosis, while oocytes degenerate late in embryogenesis prior to dictyate arrest. Using electron microscopy and immunolocalization of meiotic proteins in mutant adult spermatocytes, we found that male and female gametogenesis is severely disrupted in Atm-deficient mice as early as leptonema of prophase I, resulting in apoptotic degeneration. A small number of mutant cells progress into later stages of meiosis, but no cells proceed beyond prophase I. ATR, a protein related to ATM, DMC1, a RAD51 family member, and RAD51 are mislocalized to chromatin and have reduced localization to developing synaptonemal complexes in spermatocytes from Atm-deficient mice, suggesting dysregulation of the orderly progression of meiotic events. ATM protein is normally present at high levels primarily in ova cytoplasm of developing ovarian follicles, and in the nucleus of spermatogonia and to a lesser extent in spermatoctyes, but without localization to the synaptonemal complex. We propose a model in which ATM acts to monitor meiosis by participation in the regulation or surveillance of meiotic progression, similar to its role as a monitor of mitotic cell cycle progression.  相似文献   
16.
The effect of porcine artery elastin on serum cholesterol level was investigated in rats fed a cholesterol-free diet. Rats were fed for 4 weeks, with a diet (ED) containing 15% casein and 5% of porcine artery elastin in comparison with a diet (CD) containing 20% casein. The total serum and non-HDL-cholesterol concentrations were lower (P < 0.001) in ED-fed group than the CD-fed group at the end of the experiment. Caecal propionate concentration and Bifidobacterium and Lactobacillus population were higher (P < 0.05) in ED-fed group than the CD-fed group. The results of this study suggest that porcine artery elastin could be considered as a functional dietary protein with hypocholesterolaemic ability. Favourable amino acid composition and lysine derived cross links may at least be partially responsible for the hypocholesterolaemic ability of ED. Moreover, the higher caecal propionic acid concentration in the ED-fed group may have suppressed the cholesterol synthesis in the liver, and reduced the serum cholesterol level.  相似文献   
17.
18.
A murine model of ataxia telangiectasia was created by disrupting the Atm locus via gene targeting. Mice homozygous for the disrupted Atm allele displayed growth retardation, neurologic dysfunction, male and female infertility secondary to the absence of mature gametes, defects in T lymphocyte maturation, and extreme sensitivity to gamma-irradiation. The majority of animals developed malignant thymic lymphomas between 2 and 4 months of age. Several chromosomal anomalies were detected in one of these tumors. Fibroblasts from these mice grew slowly and exhibited abnormal radiation-induced G1 checkpoint function. Atm-disrupted mice recapitulate the ataxia telangiectasia phenotype in humans, providing a mammalian model in which to study the pathophysiology of this pleiotropic disorder.  相似文献   
19.
The wild-type strain of Clostridium beijerinckii NCIMB 8052 tends to degenerate (i.e., lose the ability to form solvents) after prolonged periods of laboratory culture. Several Tn1545 mutants of this organism showing enhanced long-term stability of solvent production were isolated. Four of them harbor identical insertions within the fms (def) gene, which encodes peptide deformylase (PDF). The C. beijerinckii fms gene product contains four diagnostic residues involved in the Zn2+ coordination and catalysis found in all PDFs, but it is unusually small, because it lacks the dispensable disordered C-terminal domain. Unlike previously characterized PDFs from Escherichia coli and Thermus thermophilus, the C. beijerinckii PDF can apparently tolerate N-terminal truncation. The Tn1545 insertion in the mutants is at a site corresponding to residue 15 of the predicted gene product. This probably removes 23 N-terminal residues from PDF, leaving a 116-residue protein. The mutant PDF retains at least partial function, and it complements an fms(Ts) strain of E. coli. Northern hybridizations indicate that the mutant gene is actively transcribed in C. beijerinckii. This can only occur from a previously unsuspected, outwardly directed promoter located close to the right end of Tn1545. The Tn1545 insertion in fms causes a reduction in the growth rate of C. beijerinckii, and, associated with this, the bacteria display an enhanced stability of solvent production. The latter phenotype can be mimicked in the wild type by reducing the growth rate. Therefore, the observed amelioration of degeneration in the mutants is probably due to their reduced growth rates.  相似文献   
20.
Wireless Personal Communications - The Internet of Things (IoT) technologies interconnect a broad range of network devices, differing in terms of size, weight, functionality, and resource...  相似文献   
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