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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.
191

Behind the Internationalization Process of Northeast Italian SMEs : An Abductive Approach

Roriz, Anna Lysie, Feletto, Nicola January 2012 (has links)
This study strives to investigate why some small and medium enterprises (SMEs) from Northeast Italy internationalize at inception and some internationalize gradually. The main literature regarding both, Born Globals and Stage-Models, were reviewed. In face of a high degree of fragmentation in the Born Global literature the study was developed through an abductive logic of reasoning. This basically means that we started by clustering already accepted internal and external factors, working then, towards a unified explanation. A qualitative study was developed with four SMEs. The main results show that no factor can singularly drive a company to internationalize at inception. Instead, the interaction of internal and external factors determines how SMEs internationalize. The findings provide empirical insights on the internationalization behavior of SMEs and redress the apparent theoretical gap in this field.
192

High performance building blocks for wireless receiver: multi-stage amplifiers and low noise amplifiers

Fan, Xiaohua 15 May 2009 (has links)
Different wireless communication systems utilizing different standards and for multiple applications have penetrated the normal people's life, such as Cell phone, Wireless LAN, Bluetooth, Ultra wideband (UWB) and WiMAX systems. The wireless receiver normally serves as the primary part of the system, which heavily influences the system performance. This research concentrates on the designs of several important blocks of the receiver; multi-stage amplifier and low noise amplifier. Two novel multi-stage amplifier typologies are proposed to improve the bandwidth and reduce the silicon area for the application where a large capacitive load exists. They were designed using AMI 0.5 m µ CMOS technology. The simulation and measurement results show they have the best Figure-of-Merits (FOMs) in terms of small signal and large signal performances, with 4.6MHz and 9MHz bandwidth while consuming 0.38mW and 0.4mW power from a 2V power supply. Two Low Noise Amplifiers (LNAs) are proposed, with one designed for narrowband application and the other for UWB application. A noise reduction technique is proposed for the differential cascode Common Source LNA (CS-LNA), which reduces the LNA Noise Figure (NF), increases the LNA gain, and improves the LNA linearity. At the same time, a novel Common Gate LNA (CG-LNA) is proposed for UWB application, which has better linearity, lower power consumption, and reasonable noise performance. Finally a novel practical current injection built-in-test (BIT) technique is proposed for the RF Front-end circuits. If the off-chip component Lg and Rs values are well controlled, the proposed technique can estimate the voltage gain of the LNA with less than 1dB (8%) error.
193

Effect of Aging Heat Treatments on Ni52Ti48 Shape Memory Alloy

Akin, Erhan 2010 August 1900 (has links)
Ni-rich NiTi shape memory alloys (SMAs) are capable of attaining a wide range of transformation temperatures depending on the heat treatment conditions and superior thermo-mechanical cycling stability, which are desired for repeated solid-state actuation. High Ni-content Ni-rich SMAs have very low transformation temperatures in a solutionized condition due to the high Ni-content of the matrix. Slow cooling (furnacecooling) from solutionizing temperature and additional aging heat treatments result in the formation of Ni-rich precipitates such as Ni4Ti3, Ni3Ti2 and Ni3Ti and increase transformation temperatures above ambient by depleting excess Ni from the matrix. However, the precipitates do not undergo a martensitic phase transformation and they decrease the transformation strain by reducing the volume fraction of the material capable of transforming. Meanwhile, recent preliminary work shows that Ni3Ti precipitates dominate fatigue failure. The objectives of the present study are: (1) to eliminate Ni3Ti but still have Ni4Ti3 precipitates, which are responsible for the dimensional stability and increase transformation temperatures, (2) to investigate the effect of heat treatments on the transformation strain, and (3) to select single variant Ni4Ti3 precipitates through constrained aging for the formation of oriented internal stress and eventually obtain twoway shame memory effect (TWSME) and enhanced dimensional stability. Based on these objectives, the effect of aging heat treatment on transformation temperatures, microstructural evolution, and shape memory behavior were investigated for a Ni52Ti48 shape memory alloy (SMA) by using differential scanning calorimetry (DSC), optical microscopy, scanning electron microscopy (SEM), and thermo-mechanical testing, including isobaric heating-cooling experiments under various stress levels. It was observed that solutionizing at 900 degree C for 24 hours eliminated Ni3Ti type precipitates, but additional aging heat treatments are needed to form Ni4Ti3 precipitates to increase transformation temperatures. Furnace-cooling and additional aging heat treatment results in the multi-stage martensitic transformation due to chemical and stress inhomogeneities in the microstructure. Aging of the controlled furnace-cooled material at 400 degree C for 48 hours resulted in the highest transformation temperatures among all processing conditions investigated due to the combination of Ni3Ti precipitates and 27 percent volume fraction of the Ni4Ti3 precipitates, which led to the depletion of Ni from the transforming matrix. However, since overaging results in losing coherency of the precipitates, dimensional stability during isobaric thermal cycling was negatively impacted.
194

DSP-Based Research on Rapid Charging Strategy of Lead-Acid Battery

Hung, Kuo-Yuan 06 July 2005 (has links)
The Lead-Acid battery has become the power source of several electron product. The major drawback is that it requires long charging time. This thesis is to design a programmable rapid charger and energy recovery scheme with DSP. Furthermore zero-voltage-switching(ZVS) capability of the adopted asymmetrical half-bridge topology enhances the power density of the charger. The energy recovery cell stores the negative pulse energy into DC bus capacitor temporarily to avoid unnecessary energy consumption in conventional schemes. This thesis is experimentally verified on 12V/7.5Ah nonspillable sealed-lead assembled batteries. According to experimental results, the charger can achieve the goal of rapid charge within 1 hour. Because of using the rapid charge algorithm, it can give different charging section depends on temperature and voltage of battery, and it can adjust the over-temperature and the over-voltage of battery to guarantee the battery be charged safely. In this thesis, a prototype module is implemented with mature protection condition. Some experiments are shown to verify the feasibility of the proposed scheme.
195

G7 business cycle synchronization and transmission mechanism.

Chou, I-Hsiu 22 June 2006 (has links)
Since Bretton Woods System break down in year 1973. Many economists found that there are more similar business cycle between industrial countries. Recently, Doyle and Faust(2002) proposed the correlation of business cycle between two countries becomes weaker. Therefore in this search, we try to carry out two different aspect factor that effects the countries¡¦ business cycle correlation. The factor is so-called ¡§transmission mechanism.¡¨ Generally specking, Many empirical analysis have pointed out the temporary factors to the business cycle mainly come from the transferred factors of economic aspect. What is ¡§Transmission Mechanisms?¡¨ Economists often try to substitute it in good markets, financial markets, and the coordination of monetary policies. However, in this duration of the empirical analysis, using only these proxy variables to explain BCCs between two countries seems too limited. According to this situation, we believe if the BCCs can be explained by using proxy factors of non-economic variable, the result can be utilized by making up the defect. We attempt to find new factors in political approach and combine with the ¡§Transmission Mechanisms¡¨ that we have introduced earlier. To analyze further economic implication in our research, five conclusions have been summarized below: Firstly, increasing bilateral trade has significantly provided positive effect to BCCs among G7 countries from 1980 to 2002. Because bilateral trade intensity index is endogenous , we use exogenous variable as instrumental variable to estimate ¡§Trade¡¨. Secondly, we use Panel method to expand its matrix. Finally, we improve the empirical estimators of insignificant statistics before. So, when we talk about the relations between BCCs and good and service markets, we must consider these exogenous factors. Eventually, we will receive more detailed results. Secondly, although to trade in financial markets can increase the BCCs between two countries, the statistic report is insignificant . About this empirical result, we can obtain reasonable explanations from the researches (for instance: Imbs, 2004 or Kose et al, 2003), they point out that financial markets are bound excessively by globalization. Therefore, this will aggravatingly make each country to focus on its specialization. Finally, this situation will make the BCCs getting collapsed among these countries. This also explains that the specialization among these countries will reduce the positive effect from the BBCs to financial markets. Thirdly, in the research, the statistics effect of the trade intensity index and specialization are significant negative. It means that when good in transaction will result in more specialization. Two countries have similar industrial structure.Imbs(2004) consider the problem is the index we use to measure bilateral trade intensity. This index was effected from two countries¡¦ size . If use Clark and van Wincoop¡¦s trade intensity index to measure the effect, we can find that significant specialization by comparative advantage effect. Fourth, there are high level financial integration between two countries, because international risk sharing result in two countries have different industrial structure. Lastly, in the research, the statistics effect of the party variables and business cycle of correlations are very significant. This also indicates the political factor will play an important role for many sources of the fluctuation tread of BCCs. In other words, when we discuss the issue of BCCs if miss the contribution of political factors to the BCCs. Then, this might cause the omitted variable biased, and finally cause the whole computation become inefficient. In addition, we can have further discussion by an input of a factor: to conserve the joint benefit of all the member countries in an economic organization, these countries need to be ruled by the same ideal political party. Otherwise, the institute will never reach its essential result. Combining all the conclusions we have shown above, we can find out the BCCs among G7 countries from 1980-2002. Besides the influence of the ¡§Transmission Mechanisms,¡¨ the result will be varied by the political factors. In conclusion, we need to consider the contribution of the political party variables to the BCCs when talking about this issue, therefore; the original theoretical model can be more persuasive. According to a statistics of IMF, the BCCs among those industrial countries are falling little by little in recent years. Therefore, consolidating trade cooperation is essential for what we believe to improve the BCCs among G7. At the same time, pass through a strong integrate monetary policy can move forward all the incumbent parties from all the countries to agree among themselves, and even reach more substantial effect. From the example like this, we might find evidence from BCCs issues by discussing the integration process in European Monetary Union.
196

Intra-industry Trade and Business Cycle Synchronization in East Asia

Huang, Chin-hui 26 June 2007 (has links)
After East Asian financial crisis in 1997 and European monetary unification in 1999, if it is suitable of establishing the Asian common monetary area becomes the hot topic. The precondition of establishing the monetary policy cooperation depends on the synchronization of various countries¡¦ business cycle co-movement. And the trade is the connector among the countries. Trade linkages seemed to have an influence on business cycle co-movement. Countries with close international trade link are more likely to be members of an optimal currency area. According to the theoretical literature, the impact of trade integration on business cycle correlation may go either way. On the one hand, if trade occurs mainly by Heckscher-Ollin or is of the Ricardian type, higher specialization would induce the industrial structures of the trading countries to diverge, resulting in less synchronized movements of business cycle. In contrast, if trade occurs mainly through intra-industry trade, specialization does not necessarily lead to less synchronized. In summary, the total effect of trade intensity on cycle correlation is theoretically ambiguous and poses a question that could only be solved empirically. The volume of trade in East Asia has increased continuously. This paper extends the study of Frankel and Rose (1998) to analyze the impact of trade integration on business cycle correlation and intra-industry trade by using SITC data and other macroeconomic factors. Moreover, using two-stage estimation and instruments to take into account the fact that trade intensity itself may be endogenous. Then, we use panel data to estimate our equation. By gathering annual information of 10 East Asian countries from 1987 to 2005, we found that higher trade integration leads higher business cycle synchronization. To sum up, intra-industry trade is the process of establishing East Asian common monetary area.
197

IC Design and Implementation of A Boosted Voltage Generator Used in Memory Devices and Low Power Discrete Cosine Transform

Kuo, Ting-Wan 02 November 2002 (has links)
The first topic of this thesis is a novel voltage tripler using 4 clocks with different phases. Both the positive and negative polarities of the voltage are generated to serve as the boosted voltage and the back bias voltage. The proposed design is carried out by pass transistors and switched capacitors. The second topic is a low-power discrete cosine transform (DCT) processor. It is suitable for portable applications. The number of clock cycles needed for processing an 8¡Ñ8 block of pixels is increased, but the chip area is reduced. The reduction of the chip area leads to the reduction of the power dissipation.
198

A study of high school English teachers' behavior, concern, cognition, and other factors of integrating information technology into English instruction.

Huang, Yen-Fen 13 August 2003 (has links)
The aim of this study is to investigate junior and senior high school English teachers¡¦ concerns and behaviors about integrating information technology into English instruction, then to observe the variance resulting from teachers having different backgrounds, and finally to explore the relationships among them. The participations in this study are332 junior and senior high school English teachers from Taipei and Kaohsiung cities. ¡§School environment scale,¡¨ ¡§Innovative teaching behavior scale,¡¨ ¡§Integrating information technology into English instruction cognition scale,¡¨ ¡§Stages of concern questionnaire,¡¨ and ¡§Integrating information technology into English instruction behavior scale¡¨ are adopted as instruments of analysis in this study. Data were analyzed in the use of mean, standard deviation, t-test, one-way ANOVA, multivariate analysis of variances, and canonical correlation. The major findings of this study are as followed: I. There are significant differences in junior and senior high school English teachers¡¦ concerns and behaviors of integrating information technology into English instruction in term of the academic degrees, time of contacting computer, time of using computer each week, time of using computer in English instruction each week, time of taking computer related training, and information literacy. II. For junior and senior high school English teachers, their school environment, cognition of integrating information technology into English instruction, innovation in teaching, and concern of integrating information technology into English instruction are significantly related to their behavior of integrating information technology into English instruction. III. English teachers use information technology in listening instruction the most, next is in speaking instruction. The information technology English teachers use most is tapes, next are VCD/DVD/CD-ROM, and cassettes. IV. The difficulties affecting information technology integrated into English instruction are lack of time, no ability to integrating information technology into English instruction, lack of trainings, and information literacy. Based on the conclusion of this study, some suggestions are made for future study.
199

Multi-stage linear slot virtual impactor for concentration of bioaerosols

Conerly, Shawn Charles 16 August 2006 (has links)
Two linear slot virtual impactor arrangements were developed and investigated in this study. Both arrangements encompassed two-stage impaction for concentration of bioaerosols. The first arrangement consisted of eight linear slot impactors in parallel for the first stage with the designed dimensions of 87 mm (3.4”) for the throat length, 0.305 mm (.012”) for the accelerator throat width, and 0.457 mm (.018”) for the receiver throat width. The second stage contained a single unit with the designed dimensions of 71 mm (2.8”) for the throat length, 0.36 mm (0.014”) for the accelerator throat width, and 0.49mm (0.019”) for the receiver throat width. The second arrangement contained a single impactor for the first stage with a designed throat length of 87 mm (3.4”), a designed accelerator throat width of 0.43 mm (.017”), and a designed receiver throat width of 0.63mm (.025”). The second stage also contained a single impactor with a designed throat length of 8.73 mm (3.4”), a designed accelerator throat width of .43 mm (.017), and a designed receiver throat width of 0.63 mm (0.25”). To verify the tolerances of the machined impactors, optical measurements were made. Both arrangements were subjected to liquid and solid particle tests and have a theoretical concentration factor of 100X. The arrangements were tested at flow rates that ranged from 10 L/min to 1000 L/min, where the collection efficiency of the minor flow was determined. An unknown acoustical phenomenon was present during aerosol tests at elevated flow rates causing low minor flow collection efficiencies. In order to test the impactors at elevated flow rates, the acoustical generation phenomenon was systematically studied and suppressed. The cutpoint for the first arrangement was 1.3µm AD, and the cutpoint for the second arrangement was 1.0 µm AD. The average Stk50 for both arrangements was 0.71. The throat velocity through the impactors ranged from 21.8 m/s to 73 m/s, and the peak efficiency for these specific throat velocities ranged from 99% to 74%, respectively.
200

Availability of the Merger and the Acquisition Activity in Taiwan's Financial Industry after the Second Stage Financial Reform

Chung, Tsai-hua 11 September 2007 (has links)
The dawn of international banking has already sparked some of the most well known mergers in the financial industry. Following the recent merger waves of the major developed economies, Taiwan¡¦s industry also engages merger and acquisitions to pursue external growth. Firms may merge for various reasons and generates totally different result in shareholder¡¦s wealth. Thus, capture the factors which drive the merger activity is very critical issue to all the participants of Taiwan¡¦s equity market. The objective of this study is to analyze the determents of target selection in the merger and acquisition activity in Taiwan¡¦s financial industry. The subject what the research are going to study and development. There is acquired Cooperative Association what characteristics are owned. Logit regression is utilized to investigate a sample of 12 listed firms which engaged mergers after the government has passed the Financial Merger Institutions Law over the period from 2000 to 2007. Consistent with literature of merger and acquisitions, the empirical result suggests that the firms with weaker debt structure, good loan quality and Capital Adequacy, to become good targets.

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