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91.
"职业教育就是就业教育"。进行职业生涯规划,就是为自己构筑人生的宏伟大厦。职校生因生源基础、生活阅历以及客观环境等局限,对自我和社会往往缺乏全面、正确的认识,不能审时度势、科学抉择,正确规划自己的职业人生,他们在生涯规划时易陷进一些误区。明确这些误区,旨在正视生涯教育,启迪职校生的心灵成长。  相似文献   
92.
A problem of testing of hypotheses on the mean vector of a multivariate normal distribution with unknown and positive definite covariance matrix is considered when a sample with a special, though not unusual, pattern of missing observations from that population is available. The approximate percentage points of the test statistic are obtained and their accuracy has been checked by comparing them with some exact percentage points which are calculated for complete samples and some special incomplete samples. The approximate percentage points are in good agreement with exact percentage points. The above work is extended to the problem of testing the hypothesis of equality of two mean vectors of two multivariate normal distributions with the same, unknown covariance matrix  相似文献   
93.
In some situations, an appropriate quality measure uses three or more discrete levels to classify a product characteristic. For these situations, some control charts have been developed based on statistical criteria regardless of economic considerations. In this paper, we develop economic and economic statistical designs (ESD) for 3-level control charts. We apply the cost model proposed by Costa and Rahim.[Economic design of X charts with variable parameters: the Markov chain approach, J Appl Stat 28 (2001), 875–885] Furthermore, we assume that the length of time that the process remains in control is exponentially distributed which allows us to apply the Markov chain approach for developing the cost model. We apply a genetic algorithm to determine the optimal values of model parameters by minimizing the cost function. A numerical example is provided to illustrate the performance of the proposed models and to compare the cost of the pure economic and ESD for three-level control charts. A sensitivity analysis is also conducted in this numerical example.  相似文献   
94.
We present the maximum likelihood estimation (MLE) via particle swarm optimization (PSO) algorithm to estimate the mixture of two Weibull parameters with complete and multiple censored data. A simulation study is conducted to assess the performance of the MLE via PSO algorithm, quasi-Newton method and expectation-maximization (EM) algorithm for different parameter settings and sample sizes in both uncensored and censored cases. The simulation results showed that the PSO algorithm outperforms the quasi-Newton method and the EM algorithm in most cases regarding bias and root mean square errors. Two numerical examples are used to demonstrate the performance of our proposed method.  相似文献   
95.
Motivated by classification issues that arise in marine studies, we propose a latent-class mixture model for the unsupervised classification of incomplete quadrivariate data with two linear and two circular components. The model integrates bivariate circular densities and bivariate skew normal densities to capture the association between toroidal clusters of bivariate circular observations and planar clusters of bivariate linear observations. Maximum-likelihood estimation of the model is facilitated by an expectation maximization (EM) algorithm that treats unknown class membership and missing values as different sources of incomplete information. The model is exploited on hourly observations of wind speed and direction and wave height and direction to identify a number of sea regimes, which represent specific distributional shapes that the data take under environmental latent conditions.  相似文献   
96.
The paper explores the degree to which Indigenous groups perceive that resource management plans they develop are able to help deliver outcomes they seek through formal planning systems. It does this by a case study of practice in Aotearoa New Zealand. Some Indigenous groups are concerned they are being encouraged to devote considerable effort to production of major planning documents for use in interaction with environmental agencies, yet in practice, such plans can appear to have a limited role in bringing about desired change or affecting wider planning processes. The research contributes a New Zealand dimension to this international debate.  相似文献   
97.
Neighbourhood planning (NP) as enabled by the 2011 Localism Act in England has precipitated a considerable literature discussing its potential, limitations and likely shortcomings referenced against government rhetoric and the reporting of initial experiences of the process. This paper provides an overview of the current literature on neighbourhood planning and sets out how it has been received and practised across England drawing on empirical evidence. The extent of take-up and the experience of those involved in the first five years of neighbourhood planning is used to consider how community-led planning may be designed and used following operational principles of inclusivity, capacity-building and adding value.  相似文献   
98.
园林景观规划设计与地域文化   总被引:1,自引:0,他引:1  
地域文化的缺失导致园林景观规划设计及其实施效果呈现雷同的趋势,通过提出规划设计中地域文化的范畴和意义,强调了体现地域文化在规划设计中的重要性。借助三个实际的规划设计案例从宏观角度提出规划概念应与地域自然特点、人文特点等要素有机结合,从而从微观角度提出设计可采用保留、抽取、融合、再现等手法来体现地域文化。此外,在规划设计中运用地域文化应该注意契合性、创新性、烂漫性及可实施性等的几个方面的问题。  相似文献   
99.
In this paper, we analyze the emerging retail practice of carrying a combined product assortment consisting of both regular “standard” products and more fashionable and short-lived “special” products. The purpose of this practice is to increase store traffic by attracting heterogeneous classes of customers, which drives up sales of standard products due to the potential cross-selling effect. Customers who are primarily attracted by special products will also buy some standard products. In this context, we analyze three decisions that are crucial for a retailer׳s commercial success: the product assortment, the inventory levels and the pricing. We propose an optimization model and an iterative heuristic to analyze the trade-offs between the combined product assortment, the inventory level and the price per product when there is limited shelf space. Using numerical experiments, we show that our heuristic can be trusted and that its accuracy improves when the number of products increases. Our findings indicate that to attract more customers for standard products, a retailer may benefit from carrying low priced special products which, if considered in isolation, would be non-profitable. As the cross-selling effect decreases, a retailer should focus more on the standard assortment by increasing its size and decreasing the prices. However, introducing special products and ignoring the cross-selling effect may decrease a retailer׳s profitability. We show that the introduction of special products involves more than just choosing the right specials for non-loyal customers but impacts the global assortment planning, the standard products and the products pricing.  相似文献   
100.
Tactical production-distribution planning models have attracted a great deal of attention in the past decades. In these models, production and distribution decisions are considered simultaneously such that the combined plans are more advantageous than the plans resolved in a hierarchical planning process. We consider a two-stage production process, where in the first stage raw materials are transformed into continuous resources that feed the discrete production of end products in the second stage. Moreover, the setup times and costs of resources depend on the sequence in which they are processed in the first stage. The minimum scheduling unit is the product family which consists of products sharing common resources and manufacturing processes. Based on different mathematical modelling approaches to the production in the first stage, we develop a sequence-oriented formulation and a product-oriented formulation, and propose decomposition-based heuristics to solve this problem efficiently. By considering these dependencies arising in practical production processes, our model can be applied to various industrial cases, such as the beverage industry or the steel industry. Computation tests on instances from an industrial application are provided at the end of the paper.  相似文献   
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