12 resultados para 091006 Manufacturing Processes and Technologies (excl. Textiles)

em Digital Commons at Florida International University


Relevância:

100.00% 100.00%

Publicador:

Resumo:

Climate change is one of the most important and urgent issues of our time. Since 2006, China has overtaken the United States as the world’s largest greenhouse gas (GHG) emitter. China’s role in an international climate change solution has gained increased attention. Although much literature has addressed the functioning, performance, and implications of existing climate change mitigation policies and actions in China, there is insufficient literature that illuminates how the national climate change mitigation policies have been formulated and shaped. This research utilizes the policy network approach to explore China’s climate change mitigation policy making by examining how a variety of government, business, and civil society actors have formed networks to address environmental contexts and influence the policy outcomes and changes. The study is qualitative in nature. Three cases are selected to illustrate structural and interactive features of the specific policy network settings in shaping different policy arrangements and influencing the outcomes in the Chinese context. The three cases include the regulatory evolution of China’s climate change policy making; the country’s involvement in the Clean Development Mechanism (CDM) activity, and China’s exploration of voluntary agreement through adopting the Top-1000 Industrial Energy Conservation Program. The historical analysis of the policy process uses both primary data from interviews and fieldwork, and secondary data from relevant literature. The study finds that the Chinese central government dominates domestic climate change policy making; however, expanded action networks that involve actors at all levels have emerged in correspondence to diverse climate mitigation policy arrangements. The improved openness and accessibility of climate change policy network have contributed to its proactive engagement in promoting mitigation outcomes. In conclusion, the research suggests that the policy network approach provides a useful tool for studying China’s climate change policy making process. The involvement of various types of state and non-state actors has shaped new relations and affected the policy outcomes and changes. In addition, through the cross-case analysis, the study challenges the “fragmented authoritarianism” model and argues that this once-influential model is not appropriate in explaining new development and changes of policy making processes in contemporary China.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

In exploring the role of social influences in the development of the self, the current study evaluated whether young adults use social comparisons in developing their hoped-for possible selves and, if so, whether their developmental process correlates with self-regulatory processes and positive mental health outcomes. The current study found the following: (1) the domains of hoped-for possible selves among young adults were related to the gender of the social comparison target, (2) the direction of young adults' social comparison processes (upward or downward) did not significantly influence self-regulatory processes (self-efficacy and outcome expectancy) toward achieving their hoped-for possible selves, (3) strong masculine gender identification related to greater outcome expectancy, while strong feminine gender identification related to both greater self-efficacy and outcome expectancy, and (4) self-efficacy related to less state anxiety, trait anxiety, and depression, while outcome expectancy related only to less trait anxiety. Males and females were found to use traditional gender role identification in forming their hoped-for possible selves.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Recently, researchers have begun to investigate the benefits of cross-training teams. It has been hypothesized that cross-training should help improve team processes and team performance (Cannon-Bowers, Salas, Blickensderfer, & Bowers, 1998; Travillian, Volpe, Cannon-Bowers, & Salas, 1993). The current study extends previous research by examining different methods of cross-training (positional clarification and positional modeling) and the impact they have on team process and performance in both more complex and less complex environments. One hundred and thirty-five psychology undergraduates were placed in 45 three-person teams. Participants were randomly assigned to roles within teams. Teams were asked to “fly” a series of missions on a PC-based helicopter flight simulation. ^ Results suggest that cross-training improves team mental model accuracy and similarity. Accuracy of team mental models was found to be a predictor of coordination quality, but similarity of team mental models was not. Neither similarity nor accuracy of team mental models was found to be a predictor of backup behavior (quality and quantity). As expected, both team coordination (quality) and backup behaviors (quantity and quality) were significant predictors of overall team performance. Contrary to expectations, there was no interaction between cross-training and environmental complexity. Results from this study further cross-training research by establishing positional clarification and positional modeling as training strategies for improving team performance. ^

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The theoretical construct of control has been defined as necessary (Etzioni, 1965), ubiquitous (Vickers, 1967), and on-going (E. Langer, 1983). Empirical measures, however, have not adequately given meaning to this potent construct, especially within complex organizations such as schools. Four stages of theory-development and empirical testing of school building managerial control using principals and teachers working within the nation's fourth largest district are presented in this dissertation as follows: (1) a review and synthesis of social science theories of control across the literatures of organizational theory, political science, sociology, psychology, and philosophy; (2) a systematic analysis of school managerial activities performed at the building level within the context of curricular and instructional tasks; (3) the development of a survey questionnaire to measure school building managerial control; and (4) initial tests of construct validity including inter-item reliability statistics, principal components analyses, and multivariate tests of significance. The social science synthesis provided support of four managerial control processes: standards, information, assessment, and incentives. The systematic analysis of school managerial activities led to further categorization between structural frequency of behaviors and discretionary qualities of behaviors across each of the control processes and the curricular and instructional tasks. Teacher survey responses (N=486) reported a significant difference between these two dimensions of control, structural frequency and discretionary qualities, for standards, information, and assessments, but not for incentives. The descriptive model of school managerial control suggests that (1) teachers perceive structural and discretionary managerial behaviors under information and incentives more clearly than activities representing standards or assessments, (2) standards are primarily structural while assessments are primarily qualitative, (3) teacher satisfaction is most closely related to the equitable distribution of incentives, (4) each of the structural managerial behaviors has a qualitative effect on teachers, and that (5) certain qualities of managerial behaviors are perceived by teachers as distinctly discretionary, apart from school structure. The variables of teacher tenure and school effectiveness reported significant effects on school managerial control processes, while instructional levels (elementary, junior, and senior) and individual school differences were not found to be significant for the construct of school managerial control.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

In exploring the role of social influences in the development of the self, the current study evaluated whether young adults use social comparisons in developing their hoped-for possible selves and, if so, whether their developmental process correlates with self-regulatory processes and positive mental health outcomes. The current study found the following: (1) the domains of hoped-for possible selves among young adults were related to the gender of the social comparison target, (2) the direction of young adults’ social comparison processes (upward or downward) did not significantly influence self-regulatory processes (self-efficacy and outcome expectancy) toward achieving their hoped-for possible selves, (3) strong masculine gender identification related to greater outcome expectancy, while strong feminine gender identification related to both greater self-efficacy and outcome expectancy, and (4) self-efficacy related to less state anxiety, trait anxiety, and depression, while outcome expectancy related only to less trait anxiety. Males and females were found to use traditional gender role identification in forming their hoped-for possible selves.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The total time a customer spends in the business process system, called the customer cycle-time, is a major contributor to overall customer satisfaction. Business process analysts and designers are frequently asked to design process solutions with optimal performance. Simulation models have been very popular to quantitatively evaluate the business processes; however, simulation is time-consuming and it also requires extensive modeling experiences to develop simulation models. Moreover, simulation models neither provide recommendations nor yield optimal solutions for business process design. A queueing network model is a good analytical approach toward business process analysis and design, and can provide a useful abstraction of a business process. However, the existing queueing network models were developed based on telephone systems or applied to manufacturing processes in which machine servers dominate the system. In a business process, the servers are usually people. The characteristics of human servers should be taken into account by the queueing model, i.e. specialization and coordination. ^ The research described in this dissertation develops an open queueing network model to do a quick analysis of business processes. Additionally, optimization models are developed to provide optimal business process designs. The queueing network model extends and improves upon existing multi-class open-queueing network models (MOQN) so that the customer flow in the human-server oriented processes can be modeled. The optimization models help business process designers to find the optimal design of a business process with consideration of specialization and coordination. ^ The main findings of the research are, first, parallelization can reduce the cycle-time for those customer classes that require more than one parallel activity; however, the coordination time due to the parallelization overwhelms the savings from parallelization under the high utilization servers since the waiting time significantly increases, thus the cycle-time increases. Third, the level of industrial technology employed by a company and coordination time to mange the tasks have strongest impact on the business process design; as the level of industrial technology employed by the company is high; more division is required to improve the cycle-time; as the coordination time required is high; consolidation is required to improve the cycle-time. ^

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Structural Health Monitoring (SHM) systems were developed to evaluate the integrity of a system during operation, and to quickly identify the maintenance problems. They will be used in future aerospace vehicles to improve safety, reduce cost and minimize the maintenance time of a system. Many SHM systems were already developed to evaluate the integrity of plates and used in marine structures. Their implementation in manufacturing processes is still expected. The application of SHM methods for complex geometries and welds are two important challenges in this area of research. This research work started by studying the characteristics of piezoelectric actuators, and a small energy harvester was designed. The output voltages at different frequencies of vibration were acquired to determine the nonlinear characteristics of the piezoelectric stripe actuators. The frequency response was evaluated experimentally. AA battery size energy harvesting devices were developed by using these actuators. When the round and square cross section devices were excited at 50 Hz frequency, they generated 16 V and 25 V respectively. The Surface Response to Excitation (SuRE) and Lamb wave methods were used to estimate the condition of parts with complex geometries. Cutting tools and welded plates were considered. Both approaches used piezoelectric elements that were attached to the surfaces of considered parts. The variation of the magnitude of the frequency response was evaluated when the SuRE method was used. The sum of the square of the differences was calculated. The envelope of the received signal was used for the analysis of wave propagation. Bi-orthogonal wavelet (Binlet) analysis was also used for the evaluation of the data obtained during Lamb wave technique. Both the Lamb wave and SuRE approaches along with the three methods for data analysis worked effectively to detect increasing tool wear. Similarly, they detected defects on the plate, on the weld, and on a separate plate without any sensor as long as it was welded to the test plate.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Physiological processes and local-scale structural dynamics of mangroves are relatively well studied. Regional-scale processes, however, are not as well understood. Here we provide long-term data on trends in structure and forest turnover at a large scale, following hurricane damage in mangrove ecosystems of South Florida, U.S.A. Twelve mangrove vegetation plots were monitored at periodic intervals, between October 1992 and March 2005. Mangrove forests of this region are defined by a −1.5 scaling relationship between mean stem diameter and stem density, mirroring self-thinning theory for mono-specific stands. This relationship is reflected in tree size frequency scaling exponents which, through time, have exhibited trends toward a community average that is indicative of full spatial resource utilization. These trends, together with an asymptotic standing biomass accumulation, indicate that coastal mangrove ecosystems do adhere to size-structured organizing principles as described for upland tree communities. Regenerative dynamics are different between areas inside and outside of the primary wind-path of Hurricane Andrew which occurred in 1992. Forest dynamic turnover rates, however, are steady through time. This suggests that ecological, more-so than structural factors, control forest productivity. In agreement, the relative mean rate of biomass growth exhibits an inverse relationship with the seasonal range of porewater salinities. The ecosystem average in forest scaling relationships may provide a useful investigative tool of mangrove community biomass relationships, as well as offer a robust indicator of general ecosystem health for use in mangrove forest ecosystem management and restoration.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The technologies that empower biometrics have been around for a number of years, but until recently these technologies have been viewed as exotic. In the not too distant future biometrics will be used to regulate internal processes and to improve services in the hospitality and tourism industries. This paper provides an understanding of the current use of biometrics in general and its practical value for the future in hospitality and tourism. The study presents a review of current practices of biometrics with special reference to the hospitality and tourism businesses, addresses key issues imposed by this technology, and identifies business and marketing implications for these industries.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

In outsourcing relationships with China, the Electronic Manufacturing (EM) and Information Technology Services (ITS) industry in Taiwan may possess such advantages as the continuing growth of its production value, complete manufacturing supply chain, low production cost and a large-scale Chinese market, and language and culture similarity compared to outsourcing to other countries. Nevertheless, the Council for Economic Planning and Development of Executive Yuan (CEPD) found that Taiwan's IT services outsourcing to China is subject to certain constraints and might not be as successful as the EM outsourcing (Aggarwal, 2003; CEPD, 2004a; CIER, 2003; Einhorn and Kriplani, 2003; Kumar and Zhu, 2006; Li and Gao, 2003; MIC, 2006). Some studies examined this issue, but failed to (1) provide statistical evidence about lower prevalence rates of IT services outsourcing, and (2) clearly explain the lower prevalence rates of IT services outsourcing by identifying similarities and differences between both types of outsourcing contexts. This research seeks to fill that gap and possibly provide potential strategic guidelines to ITS firms in Taiwan. This study adopts Transaction Cost Economics (TCE) as the theoretical basis. The basic premise is that different types of outsourcing activities may incur differing transaction costs and realize varying degrees of outsourcing success due to differential attributes of the transactions in the outsourcing process. Using primary data gathered from questionnaire surveys of ninety two firms, the results from exploratory analysis and binary logistic regression indicated that (1) when outsourcing to China, Taiwanese firms' ITS outsourcing tends to have higher level of asset specificity, uncertainty and technical skills relative to EM outsourcing, and these features indirectly reduce firms' outsourcing prevalence rates via their direct positive impacts on transaction costs; (2) Taiwanese firms' ITS outsourcing tends to have lower level of transaction structurability relative to EM outsourcing, and this feature indirectly increases firms' outsourcing prevalence rates via its direct negative impacts on transaction costs; (3) frequency does influence firms' transaction costs in ITS outsourcing positively, but does not bring impacts into their outsourcing prevalence rates, (4) relatedness does influence firms' transaction costs positively and prevalence rates negatively in ITS outsourcing, but its impacts on the prevalence rates are not caused by the mediation effects of transaction costs, and (5) firm size of outsourcing provider does not affect firms' transaction costs, but does affect their outsourcing prevalence rates in ITS outsourcing directly and positively. Using primary data gathered from face-to-face interviews of executives from seven firms, the results from inductive analysis indicated that (1) IT services outsourcing has lower prevalence rates than EM outsourcing, and (2) this result is mainly attributed to Taiwan's core competence in manufacturing and management and higher overall transaction costs of IT services outsourcing. Specifically, there is not much difference between both types of outsourcing context in the transaction characteristics of reputation and most aspects of overall comparison. Although there are some differences in the feature of firm size of the outsourcing provider, the difference doesn't cause apparent impacts on firms' overall transaction costs. The medium or above medium difference in the transaction characteristics of asset specificity, uncertainty, frequency, technical skills, transaction structurability, and relatedness has caused higher overall transaction costs for IT services outsourcing. This higher cost might cause lower prevalence rates for ITS outsourcing relative to EM outsourcing. Overall, the interview results are consistent with the statistical analyses and provide support to my expectation that in outsourcing to China, Taiwan's electronic manufacturing firms do have lower prevalence rates of IT services outsourcing relative to EM outsourcing due to higher transaction costs caused by certain attributes. To solve this problem, firms' management should aim at identifying alternative strategies and strive to reduce their overall transaction costs of IT services outsourcing by initiating appropriate strategies which fit their environment and needs.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The presences of heavy metals, organic contaminants and natural toxins in natural water bodies pose a serious threat to the environment and the health of living organisms. Therefore, there is a critical need to identify sustainable and environmentally friendly water treatment processes. In this dissertation, I focus on the fundamental studies of advanced oxidation processes and magnetic nano-materials as promising new technologies for water treatments. Advanced oxidation processes employ reactive oxygen species (ROS) which can lead to the mineralization of a number of pollutants and toxins. The rates of formation, steady-state concentrations, and kinetic parameters of hydroxyl radical and singlet oxygen produced by various TiO2 photocatalysts under UV or visible irradiations were measured using selective chemical probes. Hydroxyl radical is the dominant ROS, and its generation is dependent on experimental conditions. The optimal condition for generation of hydroxyl radical by of TiO2 coated glass microspheres is studied by response surface methodology, and the optimal conditions are applied for the degradation of dimethyl phthalate. Singlet oxygen (1O2) also plays an important role for advanced processes, so the degradation of microcystin-LR by rose bengal, an 1O2 sensitizer was studied. The measured bimolecular reaction rate constant between MC-LR and 1O2 is ∼ 106 M-1 s-1 based on competition kinetics with furfuryl alcohol. The typical adsorbent needs separation after the treatment, while magnetic iron oxides can be easily removed by a magnetic field. Maghemite and humic acid coated magnetite (HA-Fe3O4) were synthesized, characterized and applied for chromium(VI) removal. The adsorption of chromium(VI) by maghemite and HA-Fe3O4 follow a pseudo-second-order kinetic process. The adsorption of chromium(VI) by maghemite is accurately modeled using adsorption isotherms, and solution pH and presence of humic acid influence adsorption. Humic acid coated magnetite can adsorb and reduce chromium(VI) to non-toxic chromium (III), and the reaction is not highly dependent on solution pH. The functional groups associated with humic acid act as ligands lead to the Cr(III) complex via a coupled reduction-complexation mechanism. Extended X-ray absorption fine structure spectroscopy demonstrates the Cr(III) in the Cr-loaded HA-Fe 3O4 materials has six neighboring oxygen atoms in an octahedral geometry with average bond lengths of 1.98 Å.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Calbuco Volcano, in Southern Chile, has eruptive products of predominantly andesitic hornblende-bearing lava. A purpose of this work is to understand magmatic processes and how Calbuco magma chemistry is related to the explosive volcanic character. Calbuco lava has a mineral assemblage of plagioclase, hornblende, orthopyroxene, clinopyroxene, olivine, and magnetite and entrained gabbroic xenoliths with the same mineral assemblage. The presence of hornblende is evidence for dissolved water in the magma. Detailed petrographic/textural analysis has been done using petrographic microscopy and back-scattered electron imaging (BSE); geochemical analysis by electron microprobe (EPMA). Major findings include 1) that hornblende and hornblende-bearing gabbroic cumulates crystallize from Calbuco magma, 2) that plagioclase grains are compositionally zoned, recording evidence of temperature, chemical, and water content fluctuations in the magma, and 3) that hornblende is unstable under upper magma chamber conditions at Calbuco, and is breaking down into plagioclase, olivine, orthopyroxene, clinopyroxene, and magnetite in the magma.