This study is an attempt to establish a suitable speed–density functional relationship for heterogeneous traffic on urban arterials. The model must reproduce the traffic behaviour on traffic stream and satisfy all static and dynamic properties of speed–flow–density relationships. As a first attempt for Indian traffic condition, two behavioural parameters, namely the kinematic wave speed at jam (Cj) and a proposed saturation flow (λ), are estimated using empirical observations. The parameter Cj is estimated by developing a relationship between driver reaction time and vehicle position in the queue at the signalised intersection. Functional parameters are estimated using Levenberg–Marquardt algorithm implemented in the R statistical software. Numerical measures such as root mean squared error, average relative error and cumulative residual plots are used for assessing models fitness. We set out several static and dynamic properties of the flow–speed–density relationships to evaluate the models, and these properties equally hold good for both homogenous and heterogeneous traffic states. From the numerical analysis, it is found that very few models replicate empirical speed–density data traffic behaviour. However, none of the existing functional forms satisfy all the properties. To overcome the shortcomings, we proposed two new speed–density functional forms. The uniqueness of these models is that they satisfy both numerical accuracy and the properties of fundamental diagram. These new forms would certainly improve the modelling accuracy, especially in dynamic traffic studies when coupling with dynamic speed equations.
The urban-rural planning inspector system of China is hierarchical supervision over local governments from the Central Government in respect of town and country development. The comparative analysis on planning inspection system of the UK may provide experience in seeking solutions to the problems occurring in the system of China. The planning inspector system of China can be improved in six aspects such as establishing the legal status, setting up the planning inspection agency, completing the personnel management system, enhancing the legal binding force, building the internal and external supervision channel, supplementing the relieve function, and establishing the coordination mechanism of various internal supervisions. 相似文献
The effect of relative humidity (RH) and light conditions on the oxidative stability of sunflower oil (SO) stabilised with oleoresin rosemary + ascorbyl palmitate (SOR), sage + ascorbyl palmitate (SOS) and tertiary butyl hydroquinone (SOT) was investigated. The SO without additive (SOC) served as positive control. Oil samples were subjected to 3 RH (29%, 52% and 75%) and two light conditions (dark, D and fluorescent light (600 lx), L) at 60 °C for 7 days. The oxidative stability was monitored by peroxide value (PV), conjugated diene value (CDV), free fatty acids (FFAs) and Rancimat induction period (IP). A direct relationship was noted between RH and increase in PV, CDV and FFA levels irrespective of light conditions. The detrimental effect of light on the oxidative stability was prominently noted at higher RH (75%) which followed an order: SOC > SOT > SOR > SOS. The samples stored under lower RH (29% and 52%), and dark conditions were better stabilised than light‐exposed counterparts. 相似文献
Data points with small variations between them are assumed to lie close to each other on a smooth varying manifold in the feature space. Such data are hard to classify into separate classes . A sequence of face pose images with closely varying pose angles can be considered as such data. The pose angles when large enough create images that are largely differing from each other, and thus, the sequence of face images can be assumed to be on or near a nonlinear manifold. In this paper, we propose an unsupervised pose estimation method for face images based on clustered locally linear manifolds using discriminant analysis. We divide the data into multiple disjointed, locally linear and separable clusters. The problem of identifying which cluster to use is solved by dividing the entire process into two steps. The first step or projection using the entire smooth manifold identifies a rough region of interest. We use clustering techniques on entire data to form the pose-dependent classes which are then used to find the first set of discriminant functions. The second step or second projection uses trained cluster(s) from this neighbourhood to obtain a second set of discriminant functions. The idea behind such an approach is that the local neighbourhood would be linear and provide better between-class separation, and hence, the classification problem would now be simpler. 相似文献
Applying an ecological and evolutionary perspective, this study examines the evolution and the sustainability of “mixed‐mode groups,” a type of voluntary association created and organized online to interact physically in geographically defined ways. Meetup.com is a website that facilitates the creation and coordination of mixed‐mode groups. Analysis of interviews with 34Meetupgroup organizers and a longitudinal analysis of 100 randomly selectedMeetupgroups revealed the evolutionary processes at the group and population level, respectively. Specifically, the ecological factor of population density, the demographic factor of group age, the group's profit orientation, experience of leadership change and shared leadership, and external ties played decisive roles in predicting group survival. Implications of the findings for theoretical and practical contributions are discussed.相似文献
Rice is considered as staple food in many parts of the world. An issue of concern is the breakage of rice kernels in milling processes, and these broken kernels are not generally accepted by consumers. These broken kernels can be mixed with some desired additives to improve their quality and extruded for the preparation of reconstituted rice kernels or rice analogues. Various studies have been conducted for the preparation of the rice analogues in the past few decades, and recently attempts have been made to fortify these analogues with protein, certain vitamins and minerals. The main features such as colour, shape, size, texture, and cooking characteristics and cooking time of these rice‐like grains can be tailored to the requirements of specific applications by modification of the extrusion parameters. Various organisations, such as Wuxi NutriRice Co. (DSM/Buhler) and China National Cereals, Oils and Foodstuffs Corporate (COFCO), Superlative Snacks Inc., Vigui and PATH, have utilised this technique to prepare fortified and reconstituted rice. Studies have shown that it is possible to improve the nutritional quality of rice by fortified rice analogues. This article reviews research results of the many approaches to the formation of fortified rice analogues by extrusion‐based technologies. 相似文献
Since the days of Digital Subscriber Links (DSL), time domain equalizers (TEQ's) have been used to combat time dispersive channels in Multicarrier Systems. In this paper, we propose computationally inexpensive techniques to recompute TEQ weights in the presence of changes in the channel, especially over fast fading channels. The techniques use no extra information except the perturbation to the channel itself, and provide excellent approximations to the new TEQ weights. Adaptation methods for two existing Channel shortening algorithms are proposed and their performance over randomly varying, randomly perturbed channels is studied. The proposed adaptation techniques are shown to perform admirably well for small changes in channels for OFDM systems. 相似文献
The modern manufacturing organizations are adopting lean manufacturing principles so as to eliminate wastes and streamline their processes. The evaluation of leanness gains vital importance. Multiple tools/techniques are available for ensuring leanness. Due to the impreciseness and vagueness associated with decision-making problems, fuzzy logic need to be used. Relational databases enable decision-making process. This article presents a study in which fuzzy association rules mining approach has been used for leanness evaluation of an Indian modular switches manufacturing organization. The experiences gained as a result of the conduct of the study indicated that leanness evaluation could be performed by the decision makers without any constraints. 相似文献