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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
231

The Research of practicing on Human Resource Management for Small and Medium Enterprises in Taiwan

Chen, Hsuan-Yu 10 September 2007 (has links)
Small and medium enterprises (SMEs) are the foundation of Taiwan¡¦s corporate structures and the driving force behind Taiwan¡¦s economic development. The economic miracle in the past could be attributed to the high proportion (97.8%) of small enterprises in Taiwan (2005). Therefore, how small and medium enterprises use human resource management to obtain organizational competitive advantages is the motivation behind this research. High-performing and potential SMEs¡¦ practices of human resource management may be beneficial to the learning and referencing of domestic enterprises. Thus, this study focuses on enterprises which received the National SMEs Award from the Ministry of Economic Affairs and enterprises listed as ¡§small but beautiful, small but rich¡¨ on the Feb 2006 issue of CommonWealth Magazine. Through in-depth interviews, this study attempted to qualitatively induce and analyze the core practices involved in human resource management and the practices developed under and applied to various situations. Through literature review and interviews with six high-performing SMEs in Taiwan, the following results were obtained: 1.The analysis of the human resource management measures currently adopted by SMEs showed that human resource management and organizational competitive advantages are correlated. Human resource management measures are influential to human resource competence, organizational core competence, and organizational competitive advantages. 2.From a universalistic perspective, SMEs¡¦ core practices of human resource management include: sharing of operation results with employees, providing a strict recruitment procedure and valuing employees¡¦ cultural adaptation, offering highly-competitive salary, valuing cultivation of professional competence, integrating performance, salary, and development, and providing open communication channels. 3.From a contingency perspective, we probed into the SMEs¡¦ practices of human resource management developed under and applied to various contexts. The analysis of the outstanding SMEs showed that human resource management measures that enterprises have focused on to obtain competitive advantages may vary with practical contexts. Organizations can thus react and adapt to the dynamic environment and maintain or elevate their competitive advantages.
232

Innovation in Procurement: A Case Study of Sensys Traffic AB

Opoku Gyamfi, Yaw, Chen, Jason Unknown Date (has links)
Problem: There has been a limited amount of study in procurement within SMEs (Quayle, 2002). In general, for all sizes of organizations, the procurement function has often been regarded as a transactional based function and plays a supporting department to the value-adding process. These organizations view procurement as a simple function of the entire firm (Hutchins, 1992). It is more commonly found that procurement in SMEs tend to be fragmented and non-strategic (Zheng et al., 2007). Purpose: The purpose of this thesis is to investigate innovation in procurement in small and medium-sized enterprises Method: A qualitative research method with an abductive approach was used to conduct this research. A primary and secondary material was gathered from Sensys Traffic AB which was used as a case study in investigating into the innovation in procurement within small and medium-sized enterprises. Theories: The theoretical framework that was utilized in this investigation consisted of procurement processes, strategies, roles, and innovation. Conclusion: An organization can compete for the present and the future by placing more emphasis and priority within procurement in SMEs, developing the procurement department and employment skills, coordinating and collaborating within both internal and external members, forming 'win-win' relationships with suppliers, and proactively looking for ways to innovate. Furthermore, by specifically looking to innovate within these areas the procurement function can leverage itself and its firm to be able to achieve reduced total cost of ownership and higher quality products/services. These special areas which were outlined by Spray (2009) are new sourcing ideas, new insights, new partnerships and new technologies.
233

The Impact of Capital Structure Determinants on Small and Medium size Enterprise Leverage

Hashemi, Roshanak January 2013 (has links)
Finding the suitable capital structure for small and medium size enterprises, SMEs, is vital. A suitable capital structure helps SMEs to stay alive in the competitive market and has a positive effect on the national economy. Wealth maximization is the first objective of the firms, and capital structure proposition shows how a firm plans to finance its projects to meet its first objective. The purpose of this thesis is to investigate the impact of the capital structure determinants on the SMEs borrowing behavior. SMEs in this research are defined as the small independent privately held firm with less than 250 employees. In order to reach the purpose of this thesis, I have consulted the relevant theories of capital structure. By the support of the earlier studies, as well as the related theories, I have developed the testable hypotheses to examine the impact of capital structure determinants on the decomposed leverage level. To conduct this thesis, I have used the deductive approach, which is a similar approach suggested by the key reference of this study, Michaels et al (1999).   Size, age, profitability, growth, operating risk, and asset structure are selected as the determinant of capital structure. With the unique set of data gathered from 201 SMEs in Iran over the period of 2006 to 2010, the statistic panel data regression is used to analyze the empirical data. To investigate the borrowing behavior of the SMEs comprehensively, the observed SMEs were picked up from different manufacturing industries in Iran. The result of this research reveals that the impacts of capital structure determinants on SMEs leverage levels are different in terms of both magnitude and direction. The result indicates that profitability has a strong impact on SMEs borrowing decisions. Besides profitability, size and asset structure appear to have an impact on leverage level in compare with other determinants. This thesis finding shed lights on the necessity of using the maturity structure of debt (short-term debt and long-term debt) as dependent variables. Firms are more willing to finance their projects with short term debt, rather than long term debt. Long term debt is costly, and the probability of bankruptcy is higher with long term debt. Although long term debt is riskier for SMEs, but it shows the management confident in the firm’s future since it obliges the firm’s management to make legally binding future payments of interest. However, the empirical result of this study shows that all the determinants have an effect on the level of leverage in SMEs.
234

Hydrogen or syn gas production from glycerol using pyrolysis and steam gasification processes

Valliyappan, Thiruchitrambalam 04 January 2005
Glycerol is a waste by-product obtained during the production of biodiesel. Biodiesel is one of the alternative fuels used to meet our energy requirements and also carbon dioxide emission is much lesser when compared to regular diesel fuel. Biodiesel and glycerol are produced from the transesterification of vegetable oils and fats with alcohol in the presence of a catalyst. About 10 wt% of vegetable oil is converted into glycerol during the transesterification process. An increase in biodiesel production would decrease the world market price of glycerol. The objective of this work is to produce value added products such as hydrogen or syn gas and medium heating value gas from waste glycerol using pyrolysis and steam gasification processes. <p> Pyrolysis and steam gasification of glycerol reactions was carried out in an Inconel®, tubular, fixed bed down-flow reactor at atmospheric pressure. The effects of carrier gas flow rate (30mL/min-70mL/min), temperature (650oC-800oC) and different particle diameter of different packing material (quartz - 0.21-0.35mm to 3-4mm; silicon carbide 0.15 to 1mm; Ottawa sand 0.21-0.35mm to 1.0-1.15mm) on the product yield, product gas volume, composition and calorific value were studied for the pyrolysis reactions. An increase in carrier gas flow rate did not have a significant effect on syn gas production at 800oC with quartz chips diameter of 3-4mm. However, total gas yield increased from 65 to 72wt% and liquid yield decreased from 30.7 to 19.3wt% when carrier gas flow rate decreased from 70 to 30mL/min. An increase in reaction temperature, increased the gas product yield from 27.5 to 68wt% and hydrogen yield from 17 to 48.6mol%. Also, syn gas production increased from 70 to 93 mol%. A change in particle size of the packing material had a significant increase in the gas yield and hydrogen gas composition. Therefore, pyrolysis reaction at 800oC, 50mL/min of nitrogen and quartz particle diameter of 0.21-0.35mm were optimum reaction parameter values that maximise the gas product yield (71wt%), hydrogen yield (55.4mol%), syn gas yield (93mol%) and volume of product gas (1.32L/g of glycerol). The net energy recovered at this condition was 111.18 kJ/mol of glycerol fed. However, the maximum heating value of product gas (21.35 MJ/m3) was obtained at 650oC, 50mL/min of nitrogen and with a quartz packing with particle diameter of 3-4mm. <p>The steam gasification of glycerol was carried out at 800oC, with two different packing materials (0.21-0.35mm diameter of quartz and 0.15mm of silicon carbide) by changing the steam to glycerol weight ratio from 0:100 to 50:50. The addition of steam to glycerol increased the hydrogen yield from 55.4 to 64mol% and volume of the product gas from 1.32L/g for pyrolysis to 1.71L/g of glycerol. When a steam to glycerol weight ratio of 50:50 used for the gasification reaction, the glycerol was completely converted to gas and char. Optimum conditions to maximize the volume of the product gas (1.71L/g), gas yield of 94wt% and hydrogen yield of 58mol% were 800oC, 0.21-0.35mm diameter of quartz as a packing material and steam to glycerol weight ratio of 50:50. Syn gas yield and calorific value of the product gas at this condition was 92mol% and 13.5MJ/m3, respectively. The net energy recovered at this condition was 117.19 kJ/mol of glycerol fed. <p>The steam gasification of crude glycerol was carried out at 800oC, quartz size of 0.21-0.35mm as a packing material over the range of steam to crude glycerol weight ratio from 7.5:92.5 to 50:50. Gasification reaction with steam to glycerol weight ratio of 50:50 was the optimum condition to produce high yield of product gas (91.1wt%), volume of gas (1.57L/g of glycerol and methanol), hydrogen (59.1mol%) and syn gas (79.1mol%). However, the calorific value of the product gas did not change significantly by increasing the steam to glycerol weight ratio.
235

Waste Heat Recovery in Intensive Small and Medium Sized Industries : Case Study - Gästrike Härdverkstad

Bosnjak, Vjekoslav January 2012 (has links)
In order to keep a high level and to stay competitive in the world market in the future, it is important for the Swedish steel industry to improve their efficiencies continuously and to reduce the energy consumption. In order to realize these goals, the Swedish steel association Jernkotoret was found and by their initiative Triple Steelix was found in 2006 in Berglanden, a significant area for the steel industry. In 2009, the Clean Production Centre was found in Hofors in order to build a cluster of local steel manufacturers, factories and companies. One of those companies is Gästrike Härdverkstad, a small steal heat treatment industry with six employees and about 700.000 tons treated materials every year. The aim for this thesis is to suggest solutions for recovering waste heat and lowering the total energy consumption in furnaces for heat treatment in the case of Gästrike Härdverkstad. Some limitations were necessary to complete the analysis and to come to conclusions. The yearly treated material and energy prices were assumed to be constant and the yearly power consumption was estimated by an extrapolation of a one to five days measurement. Gästrike Härdverkstad is located in Uhrfors, the southern part of Åshammar, a village with 727 inhabitants. There are not any buildings with a possibility to supply heat and there is no district heating in the surroundings. The company has a power consumption of 1.40 GWh/year, of which 65.7% is consumed by the 12 main furnaces. The rest is used by eight seldom used furnaces, devices and auxiliary machines of the support process like fans, pumps, compressor, office heating, and some other. The efficiencies of the main furnaces are between 10% and 20%.The estimated energy consumption of the space heating is about 27 MWh/year, which completely can be covered by the material coolant and the combustion heat of the exhaust gases from the hardening furnaces. Since there are 10 different types of furnaces with different duties and efficiencies, the preheating furnace was taken as an example and compared with a new furnace. According to the needs of Gästrike Härdverkstad, the furnace VAW 60/100-650°C from the company Vötsch was chosen at the cost of 248,827 SEK. The payback time depends on the efficiency. With an efficiency of 40% the payback time would be about 13 years, see Figure 20. After the annealing and ageing, the finished products are cooled down in the building hall by the ambient air. In future, the possibility of preheating the material with the heat of the finished products should be considered. With an efficiency of 30.87%, one preheating furnace could bereplaced, and taken a payback time of 5 years into account; the price of the construction would be allowed to be up to 253,200 SEK.
236

Natural honey as a cryoprotectant to improve viability of vitrified bovine oocytes

2012 January 1900 (has links)
The main objective of this study was to investigate if natural honey can be used as a cryoprotecting agent (CP) in vitrification medium to improve the viability of vitrified-warmed bovine oocytes. The first study was conducted to investigate the dehydration capability of natural honey compared with sucrose, and to determine the proper concentration of honey-based medium and the optimum time for sufficiently safe dehydration of bovine oocytes. Matured cumulus-oocyte complexs (COCs) were denuded and introduced individually into different concentrations (0.25, 0.5, 1.0, 1.5 or 2.0 M) of honey and sucrose-based medium followed by rehydration in control media (TCM). Video images were recorded during dehydration and rehydration, and oocyte images were captured at 12 time intervals to calculate oocyte-volume changes during dehydration and rehydration. Results demonstrated that, in honey-based media, the maximum oocyte shrinkage was achieved after 60 sec exposure in 0.25M, 0.5M and 1.0M concentrations; while at higher concentrations 1.5M and 2.0M, the maximum dehydration occurred at 30 and 20 seconds respectively. In sucrose-based medium, the maximum oocyte shrinkage was achieved after 60 sec exposure in 0.25 or 0.5M concentrations. However, at higher concentrations (1M, 1.5M or 2M), the maximum dehydration occurred at 30, 20 and 10 sec. For rehydration, oocytes dehydrated in honey or sucrose-based medium were able to regain their original volume within 60-120 sec. However, oocytes dehydrated in higher concentrations (2M honey, and 1.5M and 2M sucrose) were rehydrated back to their original volume within 20 sec. This study concluded that natural honey and sucrose caused similar cell dehydration. Only oocytes dehydrated in 1M honey-based media reached maximal dehydration after 60 sec and equally regained original volume. Therefore, 1M of honey-based medium is suggested for sufficient and safe oocyte dehydration during vitrification. The second study was conducted to determine in vitro maturation (IVM), in vitro fertilization (IVF) and embryonic development of bovine oocytes vitrified in honey-based vitrifcation media. In Experiment 1, bovine COCs were randomly distributed in control group (non-vitrified; G1), 0.5M sucrose group (second control; G2), and 0.5M, 1M and 1.5M honey groups (G3, G4 and G5 respectively). The COCs were exposed to equilibration solution 1 (VS1) at ~ 22 oC for 5 min and to vitrification solution 2 (VS2) for 1 min, mounted on Cryotops and plunged into LN2. COCs were warmed in TCM and honey/sucrose medium at 38.5oC for 1 min, washed, matured in vitro (IVM), denuded, and immunostained to evaluate maturation. Maturation rate was significantly higher (80.7%) in control group (G1) than in vitrified groups (56, 52, 55 and 51% in G2, G3, G4 and G5, respectively) (P<.0001), whereas there was no significant difference among the vitrified groups (P>0.05). In Experiment 2, bovine COCs distributed in control (not vitrified, G1) and vitrified groups using 1M honey and 0.5M sucrose (G2 and G3 respectively), underwent for IVM, IVF and in vitro culture (IVC) for 9 days. Cleavage rate was significantly higher (P<.0001) in the control group (74%, G1, n=183) than rates of vitrified groups (51% in G2, n=137; and 42% in G3, n=131), whereas no differences among vitrified groups (P=0.0723). Rate of blastocyst formation was significantly higher (34%) in G1 than in the vitrified groups (P<.0001); however, blastocyst formation rates in the honey group were significantly higher (P=0.0026) than in the sucrose group (13% and 3% respectively). Addition of natural honey (1.0M; or 21.7%w/v) in vitrification medium can safely and sufficiently dehydrate bovine oocytes during vitrification procedure. The vitrification of bovine oocytes in 1M honey improved their post-warming maturation abtility and embryonic development.
237

Keeping the concept clear : a perspective on performing selected mezzo-soprano songs from the musicals of Stephen Sondheim

Arbogast, Jennifer L. 31 July 2012 (has links)
This study presents research relevant to the performance of four different mezzo-soprano songs from musicals composed by Stephen Sondheim. The research first gives a comprehensive overview of the contributions of Sondheim to the American Musical Theatre genre, and compares and contrasts his treatment of mezzo-soprano characters with that of his contemporaries. The project also investigates details regarding cultural and historical influences over the four musicals. Additionally, the study includes character analyses and musical analyses for each of the selected characters and their respective songs. The research is synthesized in order to provide suggestions of ways mezzo-sopranos can incorporate this research into their performance, in order to give a more informed and educated presentation of the selected pieces. / The contributions of Stephen Sondheim -- Mezzo-sopranos of the American musical -- Amy in Company (1970) -- Beth in Merrily we roll along (1981) -- The bakers wife in Into the woods (1987) -- Lynette "Squeaky" Fromme in Assassins (1990). / School of Music
238

Cross-layer adaptive transmission scheduling in wireless networks

Ngo, Minh Hanh 05 1900 (has links)
A new promising approach for wireless network optimization is from a cross-layer perspective. This thesis focuses on exploiting channel state information (CSI) from the physical layer for optimal transmission scheduling at the medium access control (MAC) layer. The first part of the thesis considers exploiting CSI via a distributed channel-aware MAC protocol. The MAC protocol is analysed using a centralized design approach and a non-cooperative game theoretic approach. Structural results are obtained and provably convergent stochastic approximation algorithms that can estimate the optimal transmission policies are proposed. Especially, in the game theoretic MAC formulation, it is proved that the best response transmission policies are threshold in the channel state and there exists a Nash equilibrium at which every user deploys a threshold transmission policy. This threshold result leads to a particularly efficient stochastic-approximation-based adaptive learning algorithm and a simple distributed implementation of the MAC protocol. Simulations show that the channel-aware MAC protocols result in system throughputs that increase with the number of users. The thesis also considers opportunistic transmission scheduling from the perspective of a single user using Markov Decision Process (MDP) approaches. Both channel state in-formation and channel memory are exploited for opportunistic transmission. First, a finite horizon MDP transmission scheduling problem is considered. The finite horizon formulation is suitable for short-term delay constraints. It is proved for the finite horizon opportunistic transmission scheduling problem that the optimal transmission policy is threshold in the buffer occupancy state and the transmission time. This two-dimensional threshold structure substantially reduces the computational complexity required to compute and implement the optimal policy. Second, the opportunistic transmission scheduling problem is formulated as an infinite horizon average cost MDP with a constraint on the average waiting cost. An advantage of the infinite horizon formulation is that the optimal policy is stationary. Using the Lagrange dynamic programming theory and the super modularity method, it is proved that the stationary optimal transmission scheduling policy is a randomized mixture of two policies that are threshold in the buffer occupancy state. A stochastic approximation algorithm and a Q-learning based algorithm that can adaptively estimate the optimal transmission scheduling policies are then proposed.
239

Design and Analysis of Medium Access Control Protocols for Broadband Wireless Networks

Cai, Lin 17 December 2009 (has links)
The next-generation wireless networks are expected to integrate diverse network architectures and various wireless access technologies to provide a robust solution for ubiquitous broadband wireless access, such as wireless local area networks (WLANs), Ultra-Wideband (UWB), and millimeter-wave (mmWave) based wireless personal area networks (WPANs), etc. To enhance the spectral efficiency and link reliability, smart antenna systems have been proposed as a promising candidate for future broadband access networks. To effectively exploit the increased capabilities of the emerging wireless networks, the different network characteristics and the underlying physical layer features need to be considered in the medium access control (MAC) design, which plays a critical role in providing efficient and fair resource sharing among multiple users. In this thesis, we comprehensively investigate the MAC design in both single- and multi-hop broadband wireless networks, with and without infrastructure support. We first develop mathematical models to identify the performance bottlenecks and constraints in the design and operation of existing MAC. We then use a cross-layer approach to mitigate the identified bottleneck problems. Finally, by evaluating the performance of the proposed protocols with analytical models and extensive simulations, we determine the optimal protocol parameters to maximize the network performance. In specific, a generic analytical framework is developed for capacity study of an IEEE 802.11 WLAN in support of non-persistent asymmetric traffic flows. The analysis can be applied for effective admission control to guarantee the quality of service (QoS) performance of multimedia applications. As the access point (AP) becomes the bottleneck in an infrastructure based WLAN, we explore the multiple-input multiple-output (MIMO) capability in the future IEEE 802.11n WLANs and propose a MIMO-aware multi-user (MU) MAC. By exploiting the multi-user degree of freedom in a MIMO system to allow the AP to communicate with multiple users in the downlink simultaneously, the proposed MU MAC can minimize the AP-bottleneck effect and significantly improve the network capacity. Other enhanced MAC mechanisms, e.g., frame aggregation and bidirectional transmissions, are also studied. Furthermore, different from a narrowband system where simultaneous transmissions by nearby neighbors collide with each other, wideband system can support multiple concurrent transmissions if the multi-user interference can be properly managed. Taking advantage of the salient features of UWB and mmWave communications, we propose an exclusive region (ER) based MAC protocol to exploit the spatial multiplexing gain of centralized UWB and mmWave based wireless networks. Moreover, instead of studying the asymptotic capacity bounds of arbitrary networks which may be too loose to be useful in realistic networks, we derive the expected capacity or transport capacity of UWB and mmWave based networks with random topology. The analysis reveals the main factors affecting the network (transport) capacity, and how to determine the best protocol parameters to maximize the network capacity. In addition, due to limited transmission range, multi-hop relay is necessary to extend the communication coverage of UWB networks. A simple, scalable, and distributed UWB MAC protocol is crucial for efficiently utilizing the large bandwidth of UWB channels and enabling numerous new applications cost-effectively. To address this issue, we further design a distributed asynchronous ER based MAC for multi-hop UWB networks and derive the optimal ER size towards the maximum network throughput. The proposed MAC can significantly improve both network throughput and fairness performance, while the throughput and fairness are usually treated as a tradeoff in other MAC protocols.
240

Comparison of four transport systems for enetric pathogens

Haidar, Belan January 2011 (has links)
ABSTRACT: Commercial swab transport systems are used for collection and transporting of fecal and other microbiological samples. This system must maintain viability and contribute to survival of microorganisms during transport to the laboratory. Four swab transport systems have been compared, eSwab, Σ- Transwab and fecalSwab, all three with flocked swabs, and Copan Venturi Transystem with rayon swabs. The study followed the recommendations from the Clinical Laboratory Standard Institute; document M40-A for recovery of Samonella, Shigella, Yersinia and Neisseria gonorrhoeae after storage for 0, 6, 24, 48 and 72 h at room- (22-25°C) and refrigerated (2-8ºC) temperature. A fecal sample has also been inoculated with Salmonella or Shigella to simulate a fecal sample positive for Salmonella or Shigella. Recovery of all strains was higher with eSwab, Σ- Transwab and fecalswab than with Copan Venturi Transystem stored at both temperatures. A heavy growth was observed with all transport systems after storage for 24, 48 and 72 h at room temperature, except for Neisseria gonorrhoeae, and Shigella. The number of CFU for all strains was constant up to 72 h at refrigerated temperature with Copan Venturi Transystem. In the experiment with fecal sample recovery of Salmonella and Shigella was best with fecalSwab at both storage temperatures. ESwab, Σ- Transwab and fecalSwab are equivalent and can be used as an alternative to Copan Venturi Transystem with better survival of enteric pathogens and Neisseria gonorrhoeae. Fecal samples should be refrigerated in order to avoid heavy overgrowth of fecal flora.

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