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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.
671

Balance Discharging for Series Connected Batteries

Chou, Su-Ping 15 June 2004 (has links)
Charge imbalance may happen to series-connected batteries during charging or discharging due to the discrepancies among batteries. The charge imbalance will cause some batteries being over-charged or over-discharged and is harmful to the battery cycle-life. Moreover, the storage capacity of the battery bank will not be effectively utilized. This thesis brings forth first the concept of charge equalization on discharging for battery banks. Various control strategies are implemented on a flyback converter with a multi-input transformer to provide the balance discharging function as well as output voltage regulation. Each battery of the battery bank is connected to a primary winding of the transformer via an active power switch. The batteries transfer their energy to load according to the residual energy in each battery. Meanwhile, by continually monitoring battery voltages, exhausted batteries can be disconnected to avoid being over-discharged. A battery bank with four series-connected lead-acid batteries is used as an example to illustrate the operation of the balance discharging circuit. The complicated calculations and precise control are accomplished by a digital signal processor (DSP). The experimental results advocate the applicability of the discharging circuit and control strategies.
672

The Influence of Arms Race of cross-Taiwan Straits on Asia¡VPacific

Shieh, Yen-wen 27 January 2005 (has links)
After having confronted for fifty years, arms race across the Taiwan Strait does not come to an end but rather deteriorate sharply in recent years. This directly puts national security of Taiwan and China in danger. Therefore, this study is to explore the development of cross-strait arms race with four phases: the US Defending ROC Era, the Post Era of Determination of ROC-US Diplomatic Relations, the Post Cold-War Era, and the Post 911 Era. In addition, this study will predict how arms race across the Taiwan Strait will develop in the future. After all, international society stresses national power, of which military forces are one of the most critical factors. Moreover, this study will bring in those Asian-Pacific countries for discussion. By focusing on different historical backgrounds of north-eastern and south-eastern Asia and by viewing with perspectives of Triangle Strategy and Neo-Realism, this study will examine the diplomatic development in the way each Asian-Pacific country interacts with China and Taiwan respectively. Ever since Taiwan withdrew from the United Nations, she has adopted diplomatic strategies such as ¡§Realistic Diplomacy,¡¨ ¡§Elastic Diplomacy,¡¨ or ¡§Double Recognition.¡¨ Nevertheless, this way is never easy but full of challenges and predicaments. If considering Taiwan¡¦s diplomatic process with those Asian-Pacific countries, we may wonder and doubt whether such diplomatic strategy as ¡§Double Recognition¡¨ can be feasible, for ¡§Double Recognition¡¨ exists only when the to-recognize country and the two recognized countries unanimously accept one another. Besides, ¡§Double Recognition¡¨ works on the premise that the two recognized countries must be countries. But whenever Taiwan utilizes ¡§Double Recognition¡¨ policy, China strongly and unyieldingly opposes this move, putting Taiwan into a predicament that she is not recognized as a country by China. It may be understandable that Taiwan embraces the ¡§Two Nations¡¨ theory, but it is no better than froth unless China concedes. In other words, Taiwan hardly gets away from being denied by China and international society, no matter how enthusiastically she raises the policies such as ¡§Two China¡¨ or ¡§One China, One Taiwan.¡¨ Therefore, the purpose of this study is to examine how Asian-Pacific countries react with one another in terms of politics, military, and economy and how these interactions affect each country, given the premise that arms race across the Taiwan Strait has been deteriorating. This study also provides some useful research findings and suggestions for Taiwan to deal with Asian-Pacific diplomatic policies.
673

Characterization and Improvement Strategies of Mobile Source Air Quality Monitoring Station¡V Using Kungkuan Station of Miaoli as An Example

Chen, Chang-Jeong 17 February 2005 (has links)
ABSTRACT It is important to improve ambient air quality by reducing the emission from mobile sources. In order to investigate the characteristics of mobile sources, the statistic of traffic flow and the measurement of suspended particles were conducted in the Gonguan air quality monitoring station of Miaoli County in this investigation. Through chemical mass balance (CMB) receptor model and backward trajectory model, the location and contribution of emission sources were further identified. Accordingly, the improvement strategies for mobile sources were further proposed to improve local ambient air quality. In order to know the traffic flow variability of motor vehicles, passenger cars, motorcycle, heavy-duty diesel trucks, and buses were recorded every 15 minutes by a video camera for both weekend and weekdays. In the meantime, TSP and PM10 were simultaneously collected with high-volume samplers. The metallic content and water-soluble ionic species of particulate matter were analyzed with an inductively coupled plasma-atomic emission spectrophotometer (ICP- AES) and an ionic chromatography (IC). Chemical composition of suspended particles was then be used for source apportionment with the CMB model. Finally, the improvement strategies for mobile source management were further proposed through the correlation of traffic flow and vehicle emission rate. The results showed that the PM10/TSP ratios of suspended particles collected at the rooftop of a four-floor building was higher than those sampled at the air quality monitoring station for all quarters except the third quarter. PM>10 is the main factor for the concentration difference of suspended particles sampled on the rooftop of the building as well as at the monitoring station. Results from traffic flow records showed that passenger cars were the major source contributing greatly to the traffic flow, while no significant variation of buses was observed in the traffic flow. The linear regression of PM>10 concentration and vehicles for different wind directions (i.e. northwest, southwest and northeast) was undertaken. The results showed that, when the winds were blown from the northwest and southwest, the determination coefficients (R2) of the regression were 0.1226 (passenger cars), 0.4821 (motorcycles), 0.1014 (heavy-duty trucks), 0.3113 (buses), and 0.1919 (total traffic flow) respectively. It was 0.6140 (passenger cars), 0.6227 (motorcycles), 0.7761 (heavy-duty trucks), 0.2111 (buses), and 0.6309 (total traffic flow), respectively, for the northeast winds. It concluded that the traffic flow has significant influence on the concentration of suspended particle at the downwind sites. Among the vehicles, heavy-duty trucks played a key role. Consequently, reducing truck flow has to be paid more attention for the improvement of ambient air quality. During the sampling period, Ca, Fe, and Al were the most abundant metals of suspended particles, while Mg, K, Zn, and Cu ranked the second. Besides, the metallic contents of suspended particles sampled at the rooftop were generally lower than those collected at the monitoring station. It suggested that street dusts had major contribution to Gonguan air quality monitoring station. Among the water-soluble ionic species, sulfate (SO42-), nitrate (NO3-), and ammonium (NH4+) were major anions, converting mainly from SO2, NOx, and NH3. The results showed that the metallic contents in the second quarter were higher than that in the fourth quarter. However, an opposite trend was observed for anions. The Back Trajectory Model and CMB were applied to analyze the suspended particle. The results showed that the seasonal variation of air pollutants was also affected by the monsoon. Though air pollutants emitted from the nearby waste incinerators and industrial districts could be transported to the sampling site, resulting in unavoidable influence on suspended particles, tail gas and fugitive dusts emitted from vehicles were the most important sources contributed to the ambient air quality. The results indicated that motor vehicles were the major source of ambient suspended particles on the road sites. Therefore, the reduction of traffic emission should be the first step of the improvement strategies for ambient air quality. Especially, the emission of road dusts resulting from the drive-through of heavy-duty trucks should be paid more attention. This study proposed two strategies for improving ambient air quality: one for raising the road serving level and the other for reducing vehicles on road at the traffic crowd section. After the road serving level was improved, the TSP, NOx, CO and THC were respectively decreased about 41, 5,765, 316, and 62 g/day. The concentration of TSP, NOx, CO, and THC was respectively decreased about 95.66 £gg/m3, 38.59 ppb, 1.93 ppm, and 1.90 ppm. After carrying out special vehicle on the road control strategy, TSP, NOx, CO, and THC could be respectively decreased about 2,136, 19,291, 169,843, and 3181g/day. The concentrations of TSP, NOx, CO, and THC were respectively decreased about 96.03 £gg/m3, 52.25 ppb, 2.05ppm and 1.69ppm.. Thus, ambient air quality can be effectively improved if the heavy-duty trucks can be controlled during the rush hour. Furthermore, a substitute road for heavy-duty trucks is another option for the improvement of ambient air quality.
674

A dynamic hashing approach to supporting load balance in P2P systems

Li, Sih-ning 19 June 2006 (has links)
In a P2P (Peer-to-Peer) system, every user node, i.e., the peer, may dynamically join and leave the system. In general, peers can exchange information and contribute portions of their resources to the community in a P2P system. They are treated functionally identical. Therefore, it is very important to efficiently locate the peer that stores a particular data item and make the system load balance in P2P systems. Chord is a structured P2P system which has a ring architecture, where a structured P2P system means that peers maintain information about what resources neighbor peers offer. It provides support for just one operation: to assign the data key to the peer by hashing. Therefore, we can efficiently locate the peer that stores a particular data key. However, in the Chord system, most of data keys may be assigned to the same peer by using the static hashing scheme, which results in the case that the load of the system not be balanced. Therefore, in this thesis, we propose a strategy which uses the dynamic hashing scheme to locate the data key based on the Chord architecture, and to maintain the load balance. A dynamic hashing allows the address space allocated to the file to be increased and reduced without reorganizing the whole file. The basic idea of a dynamic hashing approach is to split the current overflow bucket into two new buckets by using the next level hashing function without reorganizing the other buckets, and our proposed strategy uses such an approach. In our strategy, we use two data structures for a peer, one stores the data hashed to the current peer and the other one stores the data from its predecessor. When an overflow occurs in the bucket after insertion of a data key, we use the one hashing function to split data keys stored in the data bucket. If the capacity of the current peer is larger than that of its successor, we forward some data keys to the successor. Similarly, we also consider the case of an underflow occurs in the bucket after deletion of a data key. Therefore, the unbalanced condition of the load (even distribution of items to nodes) of the system can be improved based on our strategy. From our simulation results, we show that the load of the P2P system based on our strategy is much more balanced than that used in the Chord system, when there are few peers and a lot of data keys in the P2P system. We also show that the load based on our strategy is still more balanced than that used in the Chord system, when the data distribution becomes skew.
675

Investingation of the Characteristics of Polycyclic Aromatic Hydrocarbons in the Atmosphere in Kaohsiung

Lu, Chu-hsiao 23 June 2006 (has links)
The high-volume air sampling (PS-1) and micro-orifice uniform deposit impactor (MOUDI) were used to measure the concentrations of polycyclic aromatic hydrocarbons (PAHs) in the atmosphere for four seasons at Zuoying and Siaogang in Kaohsiung city, together with the size distributions. Also, the CMB (Chemical Mass Balance) receptor model was employed to determine the potential sources of PAHs. The results show that the highest concentrations of PAHs occurred in winter, being 143.9 ng/m3 and 182.9 ng/m3 at Zuoying and Siaogang, respectively; while the lowest concentrations of PAHs occurred in summer, being 81.4 ng/m3 and 95.2 ng/m3. The low-weight PAHs in the two sites were abundant in gaseous phase, being 55.89 - 95.89 % and 67.07 - 96.61 % at Zuoying and Siaogang, respectively. Meanwhile, the high-weight PAHs were almost present in particulate phase, being 55.24 - 83.50 % and 46.87 - 77.26 % at Zuoying and Siaogang, respectively. The sizes of 50th percentile of cumulative size distribution, d50 of Zuoying and Siaogang were 0.89 £gm and 0.35 £gm, respectively. Hence, most atmospheric PAHs existed in fine-particle ranges (¡Õ1.0£gm). The results of by CMB receptor modeling indicated that the major sources of pollution was exhaust emission (49 - 62 %) in Zuoying, and was burning source (49 - 64 %) in Siaogang.
676

Review the operation of Strategy Map learning growth perspective--Take private Telecommunication Company as an example

Lu, Ching-po 07 July 2006 (has links)
ABSTRACT With Balance Score Card and Strategy Map is it construct organization, linking and constructing to the financial affairs finally, its structure is causality that each perspectives with straightforward thinking . However, the operation of organizing is a system with complicated trends , have characteristic of non-linear , causal feedback , time delay between all strategy goal, use the method of System Dynamic, contribute to distinguishing the causal feedback of the complicated system, combine it with BSC, very auxiliary BSC foundation of causality under index, this has contribution to the using effectively of BSC very much, namely systematic dynamics is a handy tool that auxiliary enterprises drafted and carried out the strategy. Purpose that this paper studies: (a)Use the system dynamics method, the Strategy Map of learning and growth perspective key element the characteristic of nonlinearity , time delay in simulation, find out the staff and does not admit that learning and growth perspective the reason why the strategy carry out the activity , offer a policymaker to consult . (b)Inspecting the strategy map, the ones that probe into learning and growth perspective the strategy and internal business process are linked with the merger situation, do the basis of the strategy in order to revise and improve learning and growth. (c)Negative feedback loop produced with the dynamics method experiment simulation system operation of the system, offer a whole system to a administrator to think , make the right and best decision . Through the system dynamics method experiment simulation result: (a)By the question that negative feedback loop produces, forced learning and growth the strategy of perspectives , it is limited to benefit what has been organized the performance, strengthen learning and growth the way where the strategy of perspectives do not solve the system problem . (b)The strategy map of construction organized, but by using the system dynamics method, in imitating the course of the dynamic mechanism of the strategy map , give consideration to the strategy map other perspectives close linking (alignment ) and combining (integration ) wholly, reduce wrong decision, avoid wasting and organize resources to consume manpower time emptily. (c)Learning and growth strategy should carry out by department determine with perspective execution track casing that performance link closely while being other independently each to learn , prevent the staff at the basic level from regarding learning and growth the execution activity that perspective as surplusly, become a mere formality.
677

A study on the School-based Management Balance Mode in Kaohsiung City and Kaohsiung County

Wu, Chih-wei 25 January 2007 (has links)
The purpose of this study is to examine the opinions of elementary schools faculties and folks in Kaohsiung city and Kaohsiung county on the core school-based management balance mode in order to properly promote power and status of elementary schools faculties and folks and elementary education efficiency. This study was conducted by literature analysis and questionnaires survey. The subject of this study is the faculties and folks of the elementary schools located in Kaohsiung city and Kaohsiung county. The data was collected by the self-designed scale of the researcher, and analyzed by the statistic methods of frequency distribution, percentage, mean, standard deviation, independent samples t-test, one-way ANOVA, and chi-square test. The sampling subjects are 490 school faculties and 160 folks with valid samples of 557. The following conclusions are derived: First, our country has already had the authorized foundation to promote the core school-based management balance mode. Secondly, on the whole, the opinions of elementary schools faculties on the core school-based management balance mode are apparently different owing to the different educational background. Third, the opinions of elementary schools folks on the core school-based management balance mode are not apparently different owing to the different background and environment. Forth, the character of core school committee of balance mode is decision-making. The members should include the teacher with administration (including head of office and team leader), the teacher, principal, folks and scholars; in addition, the teacher will possess more seating and be the first one on the allocation of member seating arrangement. Lastly, the study results are analyzed and discussed to provide conclusions and suggestions for the reference of education governing authorities, school administrations and related studies.
678

A Structured Segment Tree Approach to Supporting Range Queries in P2P Systems

Huang, Tzu-lun 05 July 2007 (has links)
A Peer-to-Peer system is a distributed system whose component nodes participate in similar roles. Every user node (the peer) can exchange and contribute its resources to another one in the system. Similar to the case that peers may dynamically join and leave the system, the data will also be inserted into and removed from the system dynamically. Given a certain range, a range query will find any data item whose value within the range. For example, a range query can find all the Beatle's works between 1961 and 1968 for us. However, once the range data is distributed over a P2P system through the hash function which has been used largely in many P2P systems, the continuity of the range data is not guaranteed to exist. Therefore, finding the scattered data whose value within a certain range costs much in a P2P system. The Distributed Segment Tree method (DST) preserves the local continuity of the range data at each node by using a segment tree and can break any given range into minimum number of node intervals whose union constitutes the whole requested range. The DST method works based on the Distributed Hash Table (DHT) logic; therefore, it can be applied in any DHT-based P2P system. However, data distribution of the DST method may cause overlapping. When searching a data range, the DST method sends more number of requests than what is really needed. Although the DST method designs the Downward Load Stripping Mechanism, the load on peers still may not be balanced. The main reason of these problems is that the DST method applies the DHT logic to the P2P systems. Therefore, in this thesis, we propose a method called Structured Segment Tree (SST) that does not use the DHT logic but embeds the structure of the segment tree into the P2P systems. In fact, the P2P network topology of an SST is the structure of a segment tree. Unlike a DST, an SST can fully reflect the properties of the original segment tree. Each peer in our proposed P2P system represents a node of a segment tree. Data intervals at the same level are continuous and will not overlap with each other. The union of data intervals at a level with full nodes is totally the whole data range which the P2P system can support. When searching a data range, the SST method sends as many number of requests as needed. In addition, we add sibling links to preserve the spatial locality and speed up the search efficiency. For the issue of load balance, our SST method also performs better than the DST method. From our simulation, we show that the SST method routes less number of peers to locate the requested range data than the DST method. We also show that the load based on our method is more balanced than that based on the DST method.
679

Effect of optokinetic stimulation on human balance recovery in unexpected forward fall

Takahashi, A, Koike, Y, Kaneoke, Y, Watanabe, S, Hoshiyama, M 11 1900 (has links)
名古屋大学博士学位論文 学位の種類 : 博士(医学)(課程) 学位授与年月日:平成6年3月25日 寳珠山稔氏の博士論文として提出された
680

The Relationship between Employee Benefits and Labor Relations

Hsu, Stella 24 August 2001 (has links)
It has been a trend that employees of new generations pay much more attention to individual leisure than before. Job is no longer the only essential issue for lives, work-life balance has become a leading topic for human resource management. Compare to foreign enterprises which usually provide well employee benefits, the local companies in Taiwan, especially for the high-tech industry, had also attach importance to provide well-planned employee benefits to foster a dynamic and fun work environment for employees. Production or performance is not the only successful factor for running companies, keeping talents within organizations is significant as well. No matter economic or non-economic employee benefits, the business owners never stop thinking for providing innovative and various employee benefits to attract talents. It was obviously for high-tech industry that the employees are under high job pressure and intense competition. Moreover, to have well employee benefit programs for employees could not only help employees achieving work-life balance to improve well-being for reducing business cost, but also enhance labor relations which is no doubt the substantial element for successful companies. This study examined the relationship between employee benefits and labor relations through questionnaire survey on 228 employees from the first 1500 companies in Taiwan. The results indicated that: 1. Employee benefits satisfaction was positively significant to labor relations. 2. Employee communication was positively significant to employee benefits satisfaction and labor relations. 3. Employees with different personal features show different satisfaction at employee benefits, except for marital status and job position. 4. Employees with different personal features show different satisfaction at labor relations, except for seniority and job position. 5. No differences were found within different industries toward employee benefit satisfaction.

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