The header stack-barge: Folk technology on the north American plains

The header stack-barge was a device that farmers on the American and Canadian plains invented to adapt wheat harvesting machinery to the special requirements of their semi-arid region. Although it appeared at points scattered throughout the length of the North American plains, its greatest use was in Alberta and Saskatchewan during the 1930s. The development of the header stack-barge was an outstanding example of folk technology in the agricultural history of the Great Plains, showing the conditions under which folk invention might flourish and the way it might interact with government extension agents. The case of the header stack-barge then is of consequence both to folklore and to concepts of Great Plains regionalism.     

Multicriterion linear programming problems : (Analytical survey)

An analytical survey of man-machine interactive procedures is presented. A decision maker's capabilities to carry out some information processing operations are discussed. A list of a decision maker's elementary operations used in different interactive procedures is given and their estimations from a psychological point of view are suggested. Three main criteria for estimation of man-machine procedures are proposed: reliability of information elicitation from decision maker, insignificant sensitivity to random decision maker's errors, and good speed of convergence to solution. Some procedures are evaluated in terms of these criteria.     

Cultural Consequences on Excellence in Public Diplomacy

The purpose of this study is to advance the contextual study of public diplomacy—the inquiry into the influences of a government's contextual variables on its practice and management of public diplomacy. To meet this aim, this study investigated the empirical associations between Hofstede's cultural dimensions and Excellence in public diplomacy, a conception of excellence in public diplomacy developed from the Excellence study, based on survey data from 52 embassies in Washington, DC. The findings suggest that the uncertainty avoidance dimension has substantial and significant empirical associations with Excellence in public diplomacy. Additionally, not only low uncertainty avoidance cultures but also individualist and low power distance cultures are more conducive to the Excellence than are their counterparts. Nonetheless, the findings have an implication that, in terms of associational magnitude, the overall contextual effects of societal culture on the Excellence may not be strong.     

AN ANALYSIS OF THE DYNAMIC THEORY OF THE MULTI—PRODUCT FIRM USING THE CALCULUS OF VARIATIONS

The purpose of this paper is to present the theory of the multi-product firm in situations where the revenue function depends not only on the rate of output but also on changes in the rate of output, and, similarly, where the cost function depends on changes in the rate of factor utilization as well as the rate of their utilization. Since the analysis will utilize the calculus of variations, a general introduction to this technique is also presented. The model analyzed assumes perfect foresight and knowledge concerning the revenue, cost, and production functions, and the calculus of variations is used to derive the conditions for an extremum. The first section presents the mathematical model and the model of the firm, and the optimality conditions are discussed in the second section.     

An integrated production and inventory model for a whole manufacturing supply chain involving reverse logistics with finite horizon period

This paper proposes a model and solution method for coordinating integrated production and inventory cycles in a whole manufacturing supply chain involving reverse logistics for multiple items with finite horizon period. A whole manufacturing supply chain involving reverse logistic consists of tier-2 suppliers supplying raw materials to tier-1 suppliers, tier-1 suppliers producing parts, a manufacturer which manufactures and assembles parts from tier-1 suppliers into finished products, distributors distributing finished products to retailers, retailers selling products to end customers and a third party which collects the used finished products from end customers, dissembles collected products into parts, and feed the parts back to the supply chain. In this system, we consider a finite horizon period. A mathematical model for representing the behaviors of the system is developed. Solution methods based on decentralized and a combination of decentralized and centralized decision making process, referred to as the semi-centralized decision making process, are proposed to solve the model while the centralized decision making process is solved by a mixed integer nonlinear programming method. A numerical example is used to demonstrate the model and the solutions based on the three types of the coordination.     

Examining Localized Patterns of Air Quality Perception in Texas: A Spatial and Statistical Analysis

Environmental and human health issues associated with outdoor air pollution, such as ozone, sulfur dioxide, and other pollutants in metropolitan regions, are an area of growing concern for both policy officials and the general public. Increasing attention from the news media, new health data, and public debate over the effectiveness of clean air regulations have raised the importance of air quality in the public consciousness. While public perceptions of air quality have been studied thoroughly dating back to the 1960s, little empirical research has been conducted to explain the spatial aspects of these perceptions, particularly at the local level. Although recent studies suggest characteristics of local setting are important in shaping perceptions of air quality, the roles of proximity, neighborhood characteristics, and location have not been clarified. This study seeks to improve understanding of the major factors shaping public perceptions of air quality by examining the spatial pattern of local risk perception, the role of socioeconomic characteristics in forming these perceptions, and the relationship between perceived and scientifically measured air pollution. First, we map the spatial pattern of local air quality perceptions using Geographic Information Systems (GIS) across the Dallas and Houston metropolitan areas. Next, we explain these perceptions through local contextual factors using both bivariate correlations and multivariate regression analysis. Results indicate that perceptions of air quality in the study areas are not significantly correlated with air quality based on readings of air monitoring stations. Instead, perceptions appear to be influenced by setting (urban vs. rural), state identification, access to information, and socioeconomic characteristics such as age, race, and political identification. We discuss the implications of the findings and provide direction on how further research can provide a deeper understanding of the local contextual factors influencing public perceptions.     

Cancer risk estimation for mixtures of coal tars and benzo(a)pyrene.

Two-year chronic bioassays were conducted by using B6C3F1 female mice fed several concentrations of two different mixtures of coal tars from manufactured gas waste sites or benzo(a)pyrene (BaP). The purpose of the study was to obtain estimates of cancer potency of coal tar mixtures, by using conventional regulatory methods, for use in manufactured gas waste site remediation. A secondary purpose was to investigate the validity of using the concentration of a single potent carcinogen, in this case benzo(a)pyrene, to estimate the relative risk for a coal tar mixture. The study has shown that BaP dominates the cancer risk when its concentration is greater than 6,300 ppm in the coal tar mixture. In this case the most sensitive tissue site is the forestomach. Using low-dose linear extrapolation, the lifetime cancer risk for humans is estimated to be: Risk < 1.03 x 10(-4) (ppm coal tar in total diet) + 240 x 10(-4) (ppm BaP in total diet), based on forestomach tumors. If the BaP concentration in the coal tar mixture is less than 6,300 ppm, the more likely case, then lung tumors provide the largest estimated upper limit of risk, Risk < 2.55 x 10(-4) (ppm coal tar in total diet), with no contribution of BaP to lung tumors. The upper limit of the cancer potency (slope factor) for lifetime oral exposure to benzo(a)pyrene is 1.2 x 10(-3) per microgram per kg body weight per day from this Good Laboratory Practice (GLP) study compared with the current value of 7.3 x 10(-3) per microgram per kg body weight per day listed in the U.S. EPA Integrated Risk Information System.     

The institutionalization of knowledge transfer activities within industry–university collaborative ventures

Due to the changing competitive landscape, organizations must increasingly focus on acquiring external knowledge to advance new technologies. This study examines the institutionalization of knowledge transfer activities between industrial firms and university research centers. Data were collected from 189 firms collaborating with 21 university research centers in the US. Results show that knowledge transfer activities are facilitated when industrial firms have more mechanistic structures, cultures that are more stable and direction-oriented, and when the firm is more trusting of its university research center partner. Implications for both industry and universities, including their effect on firm performance, are discussed.     

Making Leadership Work More Effectively for Women

This article explores strategies for enhancing women's effectiveness as leaders by first recognizing that leadership itself is gendered and is enacted within a gendered context, two themes that recur throughout this issue. These contexts exist along a continuum ranging from male-dominated, hierarchical, performance-oriented, power-expressive and thus masculinized contexts at one extreme to transformational contexts that stress the empowerment of followers at the other pole. Each context suggests different strategies for making women leaders effective, emphasizing women-specific recommendations in masculinized contexts that focus on status enhancement and the legitimation of women leaders in contrast to innovative contexts with broader task goals that prove more congenial for women, as well as men, leaders.