Helyhez kötött kapcsolatok. Egy társadalmi kapcsolathálókon alapuló magyarázat a földrajzi munkamegosztás kialakulására = Ties of locality. An explanation of the development of the geographical division of labour based on social networks

A „földrajzi munkamegosztás” vagy „elhelyezkedés probléma” arra a kérdésre utal, miért alakulnak ki egy-egy gazdasági tevékenységre szakosodott földrajzi egységek, regionális gazdasági rendszerek. A hagyományos közgazdasági megközelítések a területek racionálisan kalkulálható komparatív előnyeit, a nyersanyagok vagy a piac közelségét, infrastrukturális adottságokat, útfüggőséget stb. szokták hangsúlyozni. A tanulmány szerzője a társadalmi kapcsolatok jelentőségét emeli ki, azt sugallja, hogy a területi specializálódás az egymással kapcsolatban álló, hasonlóan specializálódott többi szereplő nyomására alakul ki. A hipotézist két külföldön végzett eset tanulmány tapasztalatai alapján járja körül. ______________________ The question of "regional economic systems", "geographical division of labour" or "location problem" has an important literature. Economic approaches emphasize the rationally calculated advantages of the specialized industrial areas: the benefit of the exploitation of discovered resources, more cooperative relations, etc. The paper stresses the role of social networks in the location problem: economically specialized areas formed because of the suggestions and tips of connected enterprises, cooperative partners. The hypothesis is based on the experiences of two case studies, made in a Peruvian rural area and a Mexican modern industrial area.

The impact of CEO compensation and CEO horizon on a firm's discretionary research and development expenditures

Agency costs are said to arise as a result of the separation of ownership from control inherent in the corporate form of ownership. One such agency problem concerns the potential variance between the time horizons of principal shareholders and agent managers. Agency theory suggests that these costs can be alleviated or controlled through performance-based Chief Executive Officer (CEO) contracting. However, components of a CEO's compensation contract can exacerbate or mitigate agency-related problems (Antle and Smith, 1985). According to the horizon hypothesis, a self-serving CEO reduces discretionary research and development (R&D) expenditures to increase earnings and earnings-based bonus compensation. Agency theorists contend that a CEO's market-based compensation component can mitigate horizon problems. This study seeks to determine whether there is a relationship between CEO earnings- and market-based compensation components and R&D expenditures in the largest United States industrial firms from 1987 to 1993.^ Consistent with the horizon hypothesis, results provide evidence of a negative and statistically significant relationship between CEO cash compensation (i.e., salary and bonus) and the firm's R&D expenditures. Consistent with the expectations of agency theory, results provide evidence of a positive and statistically significant relationship between market-based CEO compensation and R&D.^ Further results of this study provide evidence of a positive and statistically significant relationship between CEO tenure and the firm's R&D expenditures. Although there is a negative relationship between CEO age and the firm's R&D, it was not statistically significant at the 0.5 level. ^

Development and implementation of a tool to assess the micro/macro elements in an organization

This study examines the congruency of planning between organizational structure and process, through an evaluation and planning model known as the Micro/Macro Dynamic Planning Grid. The model compares day-to-day planning within an organization to planning imposed by organizational administration and accrediting agencies. A survey instrument was developed to assess the micro and macro sociological analysis elements utilized by an organization.^ The Micro/Macro Dynamic Planning Grid consists of four quadrants. Each quadrant contains characteristics that reflect the interaction between the micro and macro elements of planning, objectives and goals within an organization. The Over Macro/Over Micro, Quadrant 1, contains attributes that reflect a tremendous amount of action and ongoing adjustments, typical of an organization undergoing significant changes in either leadership, program and/or structure. Over Macro/Under Micro, Quadrant 2, reflects planning characteristics found in large, bureaucratic systems with little regard given to the workings of their component parts. Under Macro/Under Micro, Quadrant 3, reflects the uncooperative, uncoordinated organization, one that contains a multiplicity of viewpoints, language, objectives and goals. Under Macro/Under Micro, Quadrant 4 represents the worst case scenario for any organization. The attributes of this quadrant are very reactive, chaotic, non-productive and redundant.^ There were three phases to the study: development of the initial instrument, pilot testing the initial instrument and item revision, and administration and assessment of the refined instrument. The survey instrument was found to be valid and reliable for the purposes and audiences herein described.^ In order to expand the applicability of the instrument to other organizational settings, the survey was administered to three professional colleges within a university.^ The first three specific research questions collectively answered, in the affirmative, the basic research question: Can the Micro/Macro Dynamic Planning Grid be applied to an organization through an organizational development tool? The first specific question: Can an instrument be constructed that applies the Micro/Macro Dynamic Planning Grid? The second specific research question: Is the constructed instrument valid and reliable? The third specific research question: Does an instrument that applies the Micro/Macro Dynamic Planning Grid assess congruency of micro and macro planning, goals and objectives within an organization? The fourth specific research question: What are the differences in the responses based on roles and responsibilities within an organization? involved statistical analysis of the response data and comparisons obtained with the demographic data. (Abstract shortened by UMI.) ^

Development and validation of an instrument to predict online student success using faculty perceptions

Distance learning is growing and transforming educational institutions. The increasing use of distance learning by higher education institutions and particularly community colleges coupled with the higher level of student attrition in online courses than in traditional classrooms suggests that increased attention should be paid to factors that affect online student course completion. The purpose of the study was to develop and validate an instrument to predict community college online student course completion based on faculty perceptions, yielding a prediction model of online course completion rates. Social Presence and Media Richness theories were used to develop a theoretically-driven measure of online course completion. This research study involved surveying 311 community college faculty who taught at least one online course in the past 2 years. Email addresses of participating faculty were provided by two south Florida community colleges. Each participant was contacted through email, and a link to an Internet survey was given. The survey response rate was 63% (192 out of 303 available questionnaires). Data were analyzed through factor analysis, alpha reliability, and multiple regression. The exploratory factor analysis using principal component analysis with varimax rotation yielded a four-factor solution that accounted for 48.8% of the variance. Consistent with Social Presence theory, the factors with their percent of variance in parentheses were: immediacy (21.2%), technological immediacy (11.0%), online communication and interactivity (10.3%), and intimacy (6.3%). Internal consistency of the four factors was calculated using Cronbach's alpha (1951) with reliability coefficients ranging between .680 and .828. Multiple regression analysis yielded a model that significantly predicted 11% of the variance of the dependent variable, the percentage of student who completed the online course. As indicated in the literature (Johnson & Keil, 2002; Newberry, 2002), Media Richness theory appears to be closely related to Social Presence theory. However, elements from this theory did not emerge in the factor analysis.

Development of risk based treatability and engineering measures for reducing exposure to lead contaminated media in the Miami inner city, Florida

A major consequence of contamination at the local level’s population as it relates to environmental health and environmental engineering is childhood lead poisoning. Environmental contamination is one of the pressing environmental concerns facing the world today. Current approaches often focus on large contaminated industrial size sites that are designated by regulatory agencies for site remediation. Prior to this study, there were no known published studies conducted at the local and smaller scale, such as neighborhoods, where often much of the contamination is present to remediate. An environmental health study of local lead-poisoning data in Liberty City, Little Haiti and eastern Little Havana in Miami-Dade County, Florida accounted for a disproportionately high number of the county’s reported childhood lead poisoning cases. An engineering system was developed and designed for a comprehensive risk management methodology that is distinctively applicable to the geographical and environmental conditions of Miami-Dade County, Florida. Furthermore, a scientific approach for interpreting environmental health concerns, while involving detailed environmental engineering control measures and methods for site remediation in contained media was developed for implementation. Test samples were obtained from residents and sites in those specific communities in Miami-Dade County, Florida (Gasana and Chamorro 2002). Currently lead does not have an Oral Assessment, Inhalation Assessment, and Oral Slope Factor; variables that are required to run a quantitative risk assessment. However, various institutional controls from federal agencies’ standards and regulation for contaminated lead in media yield adequate maximum concentration limits (MCLs). For this study an MCL of .0015 (mg/L) was used. A risk management approach concerning contaminated media involving lead demonstrates that the linkage of environmental health and environmental engineering can yield a feasible solution.

Headspace analysis of smokeless powders: Development of mass calibration methods using microdrop printing for chromatographic and ion mobility spectrometric detection

Smokeless powder additives are usually detected by their extraction from post-blast residues or unburned powder particles followed by analysis using chromatographic techniques. This work presents the first comprehensive study of the detection of the volatile and semi-volatile additives of smokeless powders using solid phase microextraction (SPME) as a sampling and pre-concentration technique. Seventy smokeless powders were studied using laboratory based chromatography techniques and a field deployable ion mobility spectrometer (IMS). The detection of diphenylamine, ethyl and methyl centralite, 2,4-dinitrotoluene, diethyl and dibutyl phthalate by IMS to associate the presence of these compounds to smokeless powders is also reported for the first time. A previously reported SPME-IMS analytical approach facilitates rapid sub-nanogram detection of the vapor phase components of smokeless powders. A mass calibration procedure for the analytical techniques used in this study was developed. Precise and accurate mass delivery of analytes in picoliter volumes was achieved using a drop-on-demand inkjet printing method. Absolute mass detection limits determined using this method for the various analytes of interest ranged between 0.03–0.8 ng for the GC-MS and between 0.03–2 ng for the IMS. Mass response graphs generated for different detection techniques help in the determination of mass extracted from the headspace of each smokeless powder. The analyte mass present in the vapor phase was sufficient for a SPME fiber to extract most analytes at amounts above the detection limits of both chromatographic techniques and the ion mobility spectrometer. Analysis of the large number of smokeless powders revealed that diphenylamine was present in the headspace of 96% of the powders. Ethyl centralite was detected in 47% of the powders and 8% of the powders had methyl centralite available for detection from the headspace sampling of the powders by SPME. Nitroglycerin was the dominant peak present in the headspace of the double-based powders. 2,4-dinitrotoluene which is another important headspace component was detected in 44% of the powders. The powders therefore have more than one headspace component and the detection of a combination of these compounds is achievable by SPME-IMS leading to an association to the presence of smokeless powders.

Investigating positive identity development in a school-based youth development project

Adolescence is a pivotal period offering both opportunities and constraints on individual development. It is during this important time that one decides upon and commits to the values, goals, and beliefs which will form one's identity and guide one throughout the lifespan. Positive youth development programs, such as the Miami Youth Development Project's Changing Lives Program, target the formation of a positive sense of identity as a critical intervention point. Through developing a coherent and positive sense of self, adolescents take control of and responsibility for their lives and their decisions. Furthermore, a positive identity has been found to be a developmental asset and is linked to lower risk behaviors and positive outcomes including increased self-esteem, sense of purpose, and a positive view of the future. Positive youth development programs, which promote positive identity development, have been found to be more strongly tied to positive outcomes including skills, values, and competencies than have contextual opportunities. As such, it is critical to determine what leads to positive identity development. ^ The current study used structural equation modeling to evaluate three potential mediators of identity development. Findings indicated good model fit where change in identity commitment and change in identity exploration were mediated by informational identity style, personal expressiveness, and identity distress. There were also significant differences found between the control and intervention groups indicative of intervention effects. The findings of the current study suggest potential areas of intervention as well as the need for further research including longitudinal study and the use of qualitative methodology. ^

Pro-Literacy: A Historical Evaluation and Presentation of Strategies That Have Influenced the Development of the Volunteer Based Adult Education

This paper will present a brief history and work of Pro-Literacy and identify the aspects that serve as a model for other volunteer organizations. Pro- Literacy is an adult literacy program that has been successful in sustaining growth and promoting literacy nationally.

Distribution of Diatoms and Development of Diatom-Based Models for Inferring Salinity and Nutrient Concentrations in Florida Bay and Adjacent Coastal Wetlands of South Florida (USA)

The composition and distribution of diatom algae inhabiting estuaries and coasts of the subtropical Americas are poorly documented, especially relative to the central role diatoms play in coastal food webs and to their potential utility as sentinels of environmental change in these threatened ecosystems. Here, we document the distribution of diatoms among the diverse habitat types and long environmental gradients represented by the shallow topographic relief of the South Florida, USA, coastline. A total of 592 species were encountered from 38 freshwater, mangrove, and marine locations in the Everglades wetland and Florida Bay during two seasonal collections, with the highest diversity occurring at sites of high salinity and low water column organic carbon concentration (WTOC). Freshwater, mangrove, and estuarine assemblages were compositionally distinct, but seasonal differences were only detected in mangrove and estuarine sites where solute concentration differed greatly between wet and dry seasons. Epiphytic, planktonic, and sediment assemblages were compositionally similar, implying a high degree of mixing along the shallow, tidal, and storm-prone coast. The relationships between diatom taxa and salinity, water total phosphorus (WTP), water total nitrogen (WTN), and WTOC concentrations were determined and incorporated into weighted averaging partial least squares regression models. Salinity was the most influential variable, resulting in a highly predictive model (r apparent 2  = 0.97, r jackknife 2  = 0.95) that can be used in the future to infer changes in coastal freshwater delivery or sea-level rise in South Florida and compositionally similar environments. Models predicting WTN (r apparent 2  = 0.75, r jackknife 2  = 0.46), WTP (r apparent 2  = 0.75, r jackknife 2  = 0.49), and WTOC (r apparent 2  = 0.79, r jackknife 2  = 0.57) were also strong, suggesting that diatoms can provide reliable inferences of changes in solute delivery to the coastal ecosystem.

Development of a Game-Based Mathematics Curriculum for Preschool

America’s deficiency in mathematics can be benefitted by an emphasis in mathematics from an early age. An effective math curriculum for preschool should consist of the most important aspects of early childhood mathematics, including number writing and identification, one-to-one correspondence, cardinality, number comparison, ordinality, number sequence, and number bonds.

The development of calibrants through characterization of volatile organic compounds from peroxide based explosives and a non-target chemical calibration compound

Detection canines represent the fastest and most versatile means of illicit material detection. This research endeavor in its most simplistic form is the improvement of detection canines through training, training aids, and calibration. This study focuses on developing a universal calibration compound for which all detection canines, regardless of detection substance, can be tested daily to ensure that they are working with acceptable parameters. Surrogate continuation aids (SCAs) were developed for peroxide based explosives along with the validation of the SCAs already developed within the International Forensic Research Institute (IFRI) prototype surrogate explosives kit. Storage parameters of the SCAs were evaluated to give recommendations to the detection canine community on the best possible training aid storage solution that minimizes the likelihood of contamination. Two commonly used and accepted detection canine imprinting methods were also evaluated for the speed in which the canine is trained and their reliability. As a result of the completion of this study, SCAs have been developed for explosive detection canine use covering: peroxide based explosives, TNT based explosives, nitroglycerin based explosives, tagged explosives, plasticized explosives, and smokeless powders. Through the use of these surrogate continuation aids a more uniform and reliable system of training can be implemented in the field than is currently used today. By examining the storage parameters of the SCAs, an ideal storage system has been developed using three levels of containment for the reduction of possible contamination. The developed calibration compound will ease the growing concerns over the legality and reliability of detection canine use by detailing the daily working parameters of the canine, allowing for Daubert rules of evidence admissibility to be applied. Through canine field testing, it has been shown that the IFRI SCAs outperform other commercially available training aids on the market. Additionally, of the imprinting methods tested, no difference was found in the speed in which the canines are trained or their reliability to detect illicit materials. Therefore, if the recommendations discovered in this study are followed, the detection canine community will greatly benefit through the use of scientifically validated training techniques and training aids.

Development of physics-based models and design optimization of power electronic conversion systems

The main objective for physics based modeling of the power converter components is to design the whole converter with respect to physical and operational constraints. Therefore, all the elements and components of the energy conversion system are modeled numerically and combined together to achieve the whole system behavioral model. Previously proposed high frequency (HF) models of power converters are based on circuit models that are only related to the parasitic inner parameters of the power devices and the connections between the components. This dissertation aims to obtain appropriate physics-based models for power conversion systems, which not only can represent the steady state behavior of the components, but also can predict their high frequency characteristics. The developed physics-based model would represent the physical device with a high level of accuracy in predicting its operating condition. The proposed physics-based model enables us to accurately develop components such as; effective EMI filters, switching algorithms and circuit topologies [7]. One of the applications of the developed modeling technique is design of new sets of topologies for high-frequency, high efficiency converters for variable speed drives. The main advantage of the modeling method, presented in this dissertation, is the practical design of an inverter for high power applications with the ability to overcome the blocking voltage limitations of available power semiconductor devices. Another advantage is selection of the best matching topology with inherent reduction of switching losses which can be utilized to improve the overall efficiency. The physics-based modeling approach, in this dissertation, makes it possible to design any power electronic conversion system to meet electromagnetic standards and design constraints. This includes physical characteristics such as; decreasing the size and weight of the package, optimized interactions with the neighboring components and higher power density. In addition, the electromagnetic behaviors and signatures can be evaluated including the study of conducted and radiated EMI interactions in addition to the design of attenuation measures and enclosures.

The effects of participation in an Internet -based project on the development of global knowledge, global mindedness, and global pedagogy among preservice social studies teachers

In order to prepare younger generations to live in a world characterized by interconnectedness, developing global and international perspectives for future teachers has been recommended by the National Council for the Social Studies and the National Council for the Accreditation of Teacher Education. The purpose of this study was to investigate the effects that participation in the International Communication and Negotiation Simulation (ICONS), an Internet-based communication project has on preservice social studies teachers' global knowledge, global mindedness, and global teaching strategies. ^ The study was conducted at a public university in South Florida. A combination of quantitative and qualitative approaches was employed. Two groups of preservice social studies teachers were chosen as participants: a control group composed of 14 preservice teachers who enrolled in a global education class in the summer semester of 1998 and an experimental group that included nine preservice teachers who took the same class in the fall semester of 1998. The summer class was conducted in a traditional format, which included lectures, classroom discussions, and student presentations. The fall class incorporated a five-week Internet-based communication project. The Global Mindedness Scale (Hett, 1993) and an adapted Test of Global Knowledge (ETS, 1981) were administered upon the completion of the class. ^ Contrasting case studies were utilized to investigate the impact of participation in the ICONS on the development of preservice teachers' global pedagogy. Four preservice teachers, two selected from each group were observed and interviewed to explore how they were infusing global perspectives into social studies curriculum and instruction during a 10-week student teaching internship in the spring semester of 1999. ^ This study had three major findings. First, preservice social studies teachers from the experimental group on average scored significantly higher than those from the control group on the global knowledge test. Second, no significant difference was found between the two groups in their mean scores on the Global Mindedness Scale. Third, all four selected preservice social studies teachers were infusing global perspectives into United States and world history curriculum and instruction during their student teaching internship. Using multiple resources was the common pedagogy. The two who participated in the ICONS were more aware of using the communication feature of the Internet and the web sites that reflect more international perspectives to facilitate teaching about the world. ^ Recommendations were made for further research and for preservice studies teacher education program development. ^

Development of a new client -server architecture for context aware mobile computing

This dissertation studies the context-aware application with its proposed algorithms at client side. The required context-aware infrastructure is discussed in depth to illustrate that such an infrastructure collects the mobile user’s context information, registers service providers, derives mobile user’s current context, distributes user context among context-aware applications, and provides tailored services. The approach proposed tries to strike a balance between the context server and mobile devices. The context acquisition is centralized at the server to ensure the reusability of context information among mobile devices, while context reasoning remains at the application level. Hence, a centralized context acquisition and distributed context reasoning are viewed as a better solution overall. The context-aware search application is designed and implemented at the server side. A new algorithm is proposed to take into consideration the user context profiles. By promoting feedback on the dynamics of the system, any prior user selection is now saved for further analysis such that it may contribute to help the results of a subsequent search. On the basis of these developments at the server side, various solutions are consequently provided at the client side. A proxy software-based component is set up for the purpose of data collection. This research endorses the belief that the proxy at the client side should contain the context reasoning component. Implementation of such a component provides credence to this belief in that the context applications are able to derive the user context profiles. Furthermore, a context cache scheme is implemented to manage the cache on the client device in order to minimize processing requirements and other resources (bandwidth, CPU cycle, power). Java and MySQL platforms are used to implement the proposed architecture and to test scenarios derived from user’s daily activities. To meet the practical demands required of a testing environment without the impositions of a heavy cost for establishing such a comprehensive infrastructure, a software simulation using a free Yahoo search API is provided as a means to evaluate the effectiveness of the design approach in a most realistic way. The integration of Yahoo search engine into the context-aware architecture design proves how context aware application can meet user demands for tailored services and products in and around the user’s environment. The test results show that the overall design is highly effective, providing new features and enriching the mobile user’s experience through a broad scope of potential applications.

Development of test-based wind-driven rain intrusion model for hurricane-induced building interior and contents damage

Major portion of hurricane-induced economic loss originates from damages to building structures. The damages on building structures are typically grouped into three main categories: exterior, interior, and contents damage. Although the latter two types of damages, in most cases, cause more than 50% of the total loss, little has been done to investigate the physical damage process and unveil the interdependence of interior damage parameters. Building interior and contents damages are mainly due to wind-driven rain (WDR) intrusion through building envelope defects, breaches, and other functional openings. The limitation of research works and subsequent knowledge gaps, are in most part due to the complexity of damage phenomena during hurricanes and lack of established measurement methodologies to quantify rainwater intrusion. This dissertation focuses on devising methodologies for large-scale experimental simulation of tropical cyclone WDR and measurements of rainwater intrusion to acquire benchmark test-based data for the development of hurricane-induced building interior and contents damage model. Target WDR parameters derived from tropical cyclone rainfall data were used to simulate the WDR characteristics at the Wall of Wind (WOW) facility. The proposed WDR simulation methodology presents detailed procedures for selection of type and number of nozzles formulated based on tropical cyclone WDR study. The simulated WDR was later used to experimentally investigate the mechanisms of rainwater deposition/intrusion in buildings. Test-based dataset of two rainwater intrusion parameters that quantify the distribution of direct impinging raindrops and surface runoff rainwater over building surface — rain admittance factor (RAF) and surface runoff coefficient (SRC), respectively —were developed using common shapes of low-rise buildings. The dataset was applied to a newly formulated WDR estimation model to predict the volume of rainwater ingress through envelope openings such as wall and roof deck breaches and window sill cracks. The validation of the new model using experimental data indicated reasonable estimation of rainwater ingress through envelope defects and breaches during tropical cyclones. The WDR estimation model and experimental dataset of WDR parameters developed in this dissertation work can be used to enhance the prediction capabilities of existing interior damage models such as the Florida Public Hurricane Loss Model (FPHLM).^