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71.
Gross pollutants are the primary targeted pollutants in urban catchment management for urban water quality improvement as well as mitigation of flood. Apart from aesthetically unattractive because of its visibility, gross pollutants also contributes to degradation of river water quality and loss of aquatic habitat as it carries harmful pollutants such as oxygen demanding material, hydrocarbons and heavy metals. This study analyzed trend of gross pollutant generated from two urban residential areas located in Selangor, Malaysia. The median value of gross pollutant load obtained fi'om the Amanah Apartment and Bandar Botanic are 347.41 kg/ha/year and 32.46 kg/ha/year, respectively. Relationship between gross pollutant wet load with rainfall depths was derived using regression equation. A significant trend of increasing gross pollutant wet load into drainage system with increasing rainfall depth was observed. The behavior of pollutant load is related to the one observed in Australia.  相似文献   
72.
PURPOSE: We wished to assess the reliability of the International League Against Epilepsy (ILAE) seizure classification system applied to infantile seizures and to test a proposed new classification. METHODS: We first analyzed 39 seizures in 20 infants (aged 1-26 months) recorded with simultaneous closed-circuit television and EEG (CCTV/EEG). EEGs and videotapes of all seizures were independently analyzed by two epileptologists blinded to clinical histories. Videotapes of each seizure were reviewed without simultaneous EEG (phase 1), and printouts of ictal EEGs were assessed without behavioral correlates (phase II). The observers classified seizures according to ILAE criteria. Interrater agreement was assessed by the kappa statistic. RESULTS: Agreement on EEG features (phase II) was moderate (= 0.54) in identifying focal ictal onsets and substantial (= 0.79) in identifying generalized onsets. In contrast, analysis of videotapes showed substantial disagreement between observers in terms of classifying seizures as partial or generalized. Therefore, agreement between observers for partial was slight (= 0.14) and fair for generalized seizures (= 0.26). Similarly, conclusions of the observers as compared with those of a consensus panel were divergent for both partial (= 0.18) and generalized seizures (= 0.30). We therefore developed an alternative classification scheme and retested interrater agreement in a review of 50 seizures in 25 other infants. With this classification scheme, there was substantial agreement between observers (= 0.72). CONCLUSIONS: With clinical observations and interictal EEGs, seizures in infants cannot be reliably classified by current ILAE criteria. In contrast, a proposed new classification scheme based solely on semiology showed substantial reliability.  相似文献   
73.
随着自动导引车(automated guided vehicles,AGV)的广泛应用,柔性制造车间中机器设备与AGV之间的协同配合日益受到重视。AGV与机器的集成调度主要研究机器分配、工序排序、搬运任务的AGV分配以及AGV路径规划。该问题是极为复杂的组合优化问题,对其研究具有重要的学术意义和应用价值。围绕问题特征,从模型与算法两个方面,对国内外最新的研究文献进行了梳理。对现有模型中的约束条件和优化目标进行了详细分类,从遗传算法、混合优化算法、仿真优化算法等五个方面综述了现有算法研究中的代表性成果。在此基础上,指出了现有研究中的不足,提出了未来的研究内容和方向。  相似文献   
74.
Basri B  Griffin MJ 《Ergonomics》2012,55(8):909-922
This study determined how backrest inclination and the frequency and magnitude of vertical seat vibration influence vibration discomfort. Subjects experienced vertical seat vibration at frequencies in the range 2.5-25 Hz at vibration magnitudes in the range 0.016-2.0 ms(-2) r.m.s. Equivalent comfort contours were determined with five backrest conditions: no backrest, and with a stationary backrest inclined at 0° (upright), 30°, 60° and 90°. Within all conditions, the frequency of greatest sensitivity to acceleration decreased with increasing vibration magnitude. Compared to an upright backrest, around the main resonance of the body, the vibration magnitudes required to cause similar discomfort were 100% greater with 60° and 90° backrest inclinations and 50% greater with a 30° backrest inclination. It is concluded that no single frequency weighting provides an accurate prediction of the discomfort caused by vertical seat vibration at all magnitudes and with all backrest conditions. PRACTITIONER SUMMARY: Vertical seat vibration is a main cause of vibration discomfort for drivers and passengers of road vehicles. A frequency weighting has been standardised for the evaluation of vertical seat vibration when sitting upright but it was not known whether this weighting is suitable for the reclined sitting postures often adopted during travel.  相似文献   
75.
We present a bottom-up aggregation approach to image segmentation. Beginning with an image, we execute a sequence of steps in which pixels are gradually merged to produce larger and larger regions. In each step, we consider pairs of adjacent regions and provide a probability measure to assess whether or not they should be included in the same segment. Our probabilistic formulation takes into account intensity and texture distributions in a local area around each region. It further incorporates priors based on the geometry of the regions. Finally, posteriors based on intensity and texture cues are combined using “a mixture of experts” formulation. This probabilistic approach is integrated into a graph coarsening scheme, providing a complete hierarchical segmentation of the image. The algorithm complexity is linear in the number of the image pixels and it requires almost no user-tuned parameters. In addition, we provide a novel evaluation scheme for image segmentation algorithms, attempting to avoid human semantic considerations that are out of scope for segmentation algorithms. Using this novel evaluation scheme, we test our method and provide a comparison to several existing segmentation algorithms.  相似文献   
76.
Human faces are remarkably similar in global properties, including size, aspect ratio, and location of main features, but can vary considerably in details across individuals, gender, race, or due to facial expression. We propose a novel method for 3D shape recovery of faces that exploits the similarity of faces. Our method obtains as input a single image and uses a mere single 3D reference model of a different person's face. Classical reconstruction methods from single images, i.e., shape-from-shading, require knowledge of the reflectance properties and lighting as well as depth values for boundary conditions. Recent methods circumvent these requirements by representing input faces as combinations (of hundreds) of stored 3D models. We propose instead to use the input image as a guide to "mold" a single reference model to reach a reconstruction of the sought 3D shape. Our method assumes Lambertian reflectance and uses harmonic representations of lighting. It has been tested on images taken under controlled viewing conditions as well as on uncontrolled images downloaded from the Internet, demonstrating its accuracy and robustness under a variety of imaging conditions and overcoming significant differences in shape between the input and reference individuals including differences in facial expressions, gender, and race.  相似文献   
77.
We introduce a new, integrated approach to uncalibrated photometric stereo. We perform 3D reconstruction of Lambertian objects using multiple images produced by unknown, directional light sources. We show how to formulate a single optimization that includes rank and integrability constraints, allowing also for missing data. We then solve this optimization using the Alternating Direction Method of Multipliers (ADMM). We conduct extensive experimental evaluation on real and synthetic data sets. Our integrated approach is particularly valuable when performing photometric stereo using as few as 4–6 images, since the integrability constraint is capable of improving estimation of the linear subspace of possible solutions. We show good improvements over prior work in these cases.  相似文献   
78.
BACKGROUND: The synthesis of betulinic acid ester using betulinic acid and oleyl alcohol catalyzed by Novozym 435 (immobilized Candida antarctica lipase) was carried out. Response surface methodology (RSM) based on a five‐level, three‐variable, central composite rotatable design (CCRD) was employed to evaluate the interactive effects of various parameters. The parameters were reaction time (8–16 h), temperature (20–60 °C) and enzyme amount (120–160 mg). RESULTS: Simultaneously increasing reaction time, temperature and amount of enzyme increased the yields of betulinic acid ester produced. CONCLUSION: The optimum conditions derived via RSM for the reaction were reaction time of 10.2 h, temperature of 53.1 °C and enzyme amount of 138 mg. The actual experimental yield was 48.5% under optimum conditions, which compared well with the maximum predicted value of 47.6%. Copyright © 2008 Society of Chemical Industry  相似文献   
79.
Engkabang fat esters were synthesized from engkabang fat using an enzyme as catalyst. The main composition of the fat esters were oleyl palmitate, oleyl stearate and oleyl oleate. The percentage yield was 93.67%. Ternary phase diagrams systems containing fat esters/surfactant/water were constructed. Several regions appeared in the ternary phase diagrams such as isotropic, homogenous, liquid crystal, two-phase and three-phase regions. Increasing the hydrophilic-lipophilic balance value of the used surfactants gave a larger homogenous and isotropic region in ternary phase diagrams of engkabang fat esters/nonionic surfactant/deionized water. Isotropic and homogenous regions in the ternary phase diagram of engkabang fat esters: PEG-40 hydrogenated castor oil (2:1)/polyoxyethylene(20) sorbitan tri-oleate/deionized water, was the largest when compared to the other ternary phase diagrams. The isotropic and homogenous region can be used as a medium in formulation of cosmetics and pharmaceutical products such as creams, lotions, balms and lipsticks.  相似文献   
80.
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