Thèses sur le sujet « None of these »
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Tzeng, Shwu-hwa, et 曾淑華(釋宗慈). « none-none ». Thesis, 2012. http://ndltd.ncl.edu.tw/handle/gw8abv.
Texte intégralChen, Mei-hui, et 陳美蕙. « none-none ». Thesis, 2012. http://ndltd.ncl.edu.tw/handle/23726683575547351385.
Texte intégralHsieh, Pei-Jung, et 謝佩容. « none-none ». Thesis, 2012. http://ndltd.ncl.edu.tw/handle/58619697925700286033.
Texte intégralYang-shasha et 楊莎莎. « none ». Thesis, 2017. http://ndltd.ncl.edu.tw/handle/56446858543508760847.
Texte intégral國立中央大學
人力資源管理研究所
105
A good performance management system is an important tool to ensure the achievement of organizational goals. An effective performance management system can not only connect individuals, departments and organizations, but also enable enterprises to improve their organizational capabilities. This study will analyze the performance management system of the A group of the case company, and get feedback on the performance management system from employees in different positions, with different years of work and education levels. After collecting and compiling the survey data, this study will discuss and put forward the problems and difficulties of the current performance management system of A group, and make suggestions and improvements advice for the performance management system of the company, in order to assist the case company in performing its performance management system, solving the problems existing within the performance management system of the case company, thereby improving the human capital qualities and organizational capabilities of the case company, and also acting as a reference for other companies in implementing the performance management system or make adjustments related to the performance management system.
Wu, Ming Hao, et 吳明豪. « none ». Thesis, 2017. http://ndltd.ncl.edu.tw/handle/38763685997182430708.
Texte intégral國立中央大學
高階主管企管碩士班
105
In recent years, computers, communications equipment and electronic products developed rapidly and sold a lot. These mobile devices require the battery to supply energy to keep the operation. With the increase in manufacturing costs and market demand, the production base has gradually shifted to China with lower human resources costs where are of the same kind and the same language with Taiwan. At the same time, the government's support, foreign investment, technology transfer and the maturity of the internal market are directly or indirectly promote the ability of Chinese manufacturers gradually increased. Therefore, many orders of Taiwan-funded manufacturers have been robbed by Chinese manufacturers. These phenomena led to the gradual decline in the market share of Taiwan-funded manufacturers. In addition, the notebook market and the Tablet PC market gradually saturated and notebook computers and tablet margins are gradually reduced. Now, Taiwan-funded battery factory's competitive advantage is gradually reduced. Taiwan-funded battery assembly plant how to transform and how to reverse the situation with innovation is already a problem. This study uses the structure-conduct-performance analysis of industrial economics to study the Simplo(Taiwan-owned) , Dynapack(Taiwan-owned) , Celxpert(Taiwan-owned) and Desay(Chinese-owned) and Sunwoda(Chinese-owned). From the industry supply and demand analysis, extended to the market structure analysis, and then understand the battery assembly plant market share, product differentiation, cost structure and so on. The article compares the pricing behavior and research, innovation and the investment of different firms. Finally, the article compares the performance of Taiwan and Chinese companies through the performance of the annual statements and financial statements of the manufacturers. The results show that, battery assembly manufacturers gradually developed in the automotive, power, energy storage lithium battery in recent years. Many industry analysts predict that these fast-growing product markets will have a good income if they can be put into production early. Analysis pointed out that the industry is highly oligopolistic market, so there is no squeeze into the forefront of manufacturers will lead to a significant decline in market competitiveness. In addition, different business models and different government policies led to the gradual decline in the competitiveness of Taiwan-funded manufacturers and Taiwanese manufacturers to increase the pressure. Therefore, the Taiwan-funded manufacturers how to join world's and China's supply chain of mobile devices, electric car brand with the original advantages, will be able to maintain the original market competitiveness.
Wu, Ping-Yao, et 吳炳瑤. « none ». Thesis, 2017. http://ndltd.ncl.edu.tw/handle/54651802112555812246.
Texte intégral國立中央大學
人力資源管理研究所在職專班
105
The purpose of this study is to explore the factors that influence the workers' horizontal movement, and to explore the impact of the recent career movement of the workers by the situation of non-border career preference and pre-employment movement. The concept of mental mobility and physical mobility has an impact on every worker, and its focus is on mobility and unpredictability among enterprises (Arthur & Rousseau, 1996b; Sullivan, Carden, & Martin, 1998). Secondly, in the theory of path dependence, it is also pointed out that the early experiences of individuals will affect the current selection and success (Bernhardt, Morris, Handcock, & Scott, 2001; Sampson & Laub, 1997, Verbruggen, Van Emmerik, Van Gils, Meng & de Grip, 2015). On the results of this study can be found, psychological flow and physical flow for the recent career career have no effect, mainly because the job is not only the psychological state of identity only, but the workers themselves have to have the skills To cross the threshold for career change; and for the borderless career tendencies and the relationship between the company, the psychological flow of workers can predict the recent changes in the behavior of the company, As described in Arthur et al., 1999; Bird, 1996; DeFillippi & Arthur, 1996), the skills and knowledge associated with the worker's career are accumulated over time, and the knowledge base for the organization and the individual is Have a considerable degree of contribution. The workers have taken the behavior of changing companies, that is, on behalf of their accumulated knowledge, technology, ability has reached a certain extent and get another business owners affirmed,In the study of the path dependence theory proposed by Bernhardt, Morris, Handcock, & Scott, 2001; Sampson & Laub, 1997), the early experiences of individuals will be influenced by current choices and successes. The meaning of the job change can be interpreted by the pluripotent perspective, as Baruch (1998) has mentioned in the study, through different positions and career conversion, the accumulation of the workers themselves in the professional areas and the ability to work Ability to improve the employability of the individual, so that in a dynamic environment, the ability to choose a better career opportunities, so that workers can thus be in the development of personal career success. The results of this study can be verified, the recent occupation of the horizontal movement model, both with their early career experience has its close relationship. Keywords: career mobility, boundaryless career concept, career development, path dependence
Fei, Pao-Ching, et 費保清. « none ». Thesis, 2017. http://ndltd.ncl.edu.tw/handle/78043185151830001994.
Texte intégral國立中央大學
人力資源管理研究所
105
The purpose of this study is to explore how physical and mental health services and welfare practices provided by enterprises can effectively improve employee satisfaction. The practices include many EAP programs as well as economic, work hour, recreational, and facilities practices. This study also explore the impact of these services and practices on job satisfaction through statistical analysis. The data is secondary data from Academic Research Database (SRDA) of the Central Research Institute's Survey Center. Total of 4,082 samples are from the survey on labor and employment status conducted in 2013, including 8 physical and mental health service, 22 welfare practices. The results show that physical and mental health services have a positive impact on job satisfaction, employee welfare have a positive impact on job satisfaction, and the influence of welfare in this study is higher than the physical and mental health services. In practical implication, the study found that the organization in the provision of related services or practices can begin with simple and easy, and most employees agree with because of having greater impact on employee satisfaction as well as cost-effectiveness purpose. Nevertheless, managers must also fulfill the obligation of notification, so that each employee knows what practices are provided by the organization, and also utilizes these practices to achieve the best results.
Liao, Wen-Yu, et 廖文佑. « none ». Thesis, 2017. http://ndltd.ncl.edu.tw/handle/76338064759691942669.
Texte intégral國立中央大學
土木工程學系
105
The barriers of facilities which dispose wastes with low radioactivity are mainly composed of concrete. But unlike the normal purpose of concrete, the barrier concrete is expected to be used for more than several hundred years.This study measures long-period experimental data to get better estimated results based on previous studies by using mixes HIC-C and HIC-M, and mixes C and M. Mixes HIC-C and HIC-M were prepared and revised from AASHTO T260 test method in 2010. So far, the experiments have been ongoing and data collected for six years. On the other hand, in 2014, mixes C and M were made according to ASTM C1556 test method. Finally, the study will make comparisons of long-period immersion method and ASTM method based on experimental procedures and test results. Based on above data and results, this study expects to seek for new methods to extend and increase concrete's durability. In this study, under different curing conditions at high temperatures of 60℃ (1、2、4 days) and 80℃ (3 days、4 days、3 days + 200℃ oven-dry 12 hours), to observe whether the concrete quality and durability will be improved. There are some tests used for this study to evaluate the effects of maintenance methods and maintenance period, including compressive strength test, porosity test, pore size distribution and resistivity test. Fibre distribution characteristics were evaluated to investigate their effect on the quality. For this purpose, an image processing technique developed in this study was employed. From the test results, the aging concrete will get higher hydration degree, and caused the chloride ions hard to penetrate into concrete body. Therefore, under the effectiveness of chloride ions penetrations, ASTM C1556 test method is recommended for concrete service life calcuations.
HSIEH, HSIAO-HSIANG, et 謝孝享. « none ». Thesis, 2017. http://ndltd.ncl.edu.tw/handle/51905675790839024289.
Texte intégral國立中央大學
大氣科學學系
105
In recent years, people pay more and more attention to air pollution, which is particularly enthusiastic discussion of particles matter (PM). PM spread everywhere in our daily life. Sea salt, exhaust gas emissions from industries, vehicle emissions and raised dust, are the main reasons of the formation of PM. PM has high environmental variability. It is far less enough to rely on the government set up by the environmental monitoring network. Because of the limitation of the expensive costs of the instruments and the difficulties of the setting of the stations, reducing the size and cost of the instrument is the main purpose to improve the observation density. There are many PM sensors with low-cost portability, but most PM sensors are calibrated indoor. This time we will test the feasibility of low-cost sensors in outdoor observation. This work mainly uses Shinyei PPD42NS use with Arduino Uno microcontroller board for PM observation. PPD42NS is PM sensor based on light scattering, the sensor installation location at the National Central University of the Science Building#2, the observation time is 2016/03/23 to 2017/03/06 for 349 days. In this work, the correlation analysis was using the real-time data of the EPA Zhongli and Pingzhen station, and the meteorological data of the NCU station. We will be divided into four for the temperature, relative humidity, wind direction, rainfall to discuss. The results show that the temperature change has no significant effect. The relative humidity has a great influence. In high relative humidity (RH> 95%), the sensor will output abnormally. Rainfall will cause the sensor to malfunction. When the east or north wind occurred, lower value appeared for the shelter of the building.
Zhang, Jing-Yue, et 張瀞月. « none ». Thesis, 2017. http://ndltd.ncl.edu.tw/handle/15991415287121226645.
Texte intégral國立中央大學
化學學系
105
Alkyl p-hydroxybenzoate, also known as parabens, have been added in personal care products as preservatives for many years. Because of its low prices, odorless and difficult hardening, they are used widely. However, the studies show that parabens may contain estrogen activity and carcinogen activity, and they are potential endocrine disruptors. Moreover, complicated environmental matrix leads to lower concentration of parabens. Therefore, developing a highly selective method to extract parabens from environmental water samples is very important. Molecularly imprinting technology has been used for preparation of polymers and it can be a high selectivity method for the target molecules analysis. According to the interaction between template molecule and functional monomer, it can be divided into pre-organized approach and self-assembly approach. In this study, using self-assembly approach to prepare molecularly imprinted polymer (MIP). Ethyl paraben (EtP) was used as template molecule, methacrylic acid (MAA) as the functional monomer, ethylene glycol dimethacrylate (EGDMA) as the cross-linker and 2,2’-azobis-isobutyronitrile (AIBN) as the initiator. The molecularly imprinted polymer has been synthesized using suspension polymerization. After polymerization, the polymer was washed by Soxhlet apparatus until no template could be detect. The molecularly imprinted polymer was proved to have a homogeneous spherical structure by SEM. A solid-phase extraction based on MIP procedure was used to extract four parabens from water samples. The optimal extraction conditions were packing 50 mg MIP and elution with 2 mL methanol, the eluent was dried under nitrogen and reconstituted with 100 μL methanol. The sample was analyzed by UHPLC-QTOF-MS. The method showed a good linearity in range of 0.15-2 μg/L. The regression coefficients (R2) exceeded 0.994, and the limit of detection (LOD) were a range from 0.040-0.045 μg/L. The method also had good accuracy (recovery 93-105%) and precision (RSD < 9%). In real samples, parabens were detected between 0.17-5.33 μg/L in Taiwan.
Zhou, Hui-Ting, et 周惠婷. « none ». Thesis, 2017. http://ndltd.ncl.edu.tw/handle/71699751393774122800.
Texte intégral國立中央大學
化學學系
105
Alkyl p-hydroxybenzoates, also known as parabens, was added in cosmetic, pharmaceutical and food as preservative since the 20th century. Because of its odorless, low prices and difficult hardening, they have widely been used by various applications. Recent studies have concluded that parabens might disrupt the endocrine system, affect funtions of human reproductive systems, and are classified as a potential endocrine disrupter. Therefore, it is important to develop a method to analyze paranbens in human urine. This study demonstrates an efficient, less solvent used, eco-friendly and rapid analysis method for the determination of parabens in human urine. The method involved the use of ultrasound-assisted emulsification microextection (USAEME) coupled with on-line derivatization GC-MS or UHPLC-QTOF-MS. The parameters of extaction method were optimized by Box-Behnken design and analysis of variance. The optimal conditions of USAEME were: after hydrolysis of 1 mL urine sample, 200 μL ethyl acetate (as an extractant) rapid injected into urine containing 0.1 g of sodium chloride in a conical bottom tube. After ultrasonication for 1 min and centrifugation at 7000 rpm for 10 min, the upper layer was taken and dried under nitrogen and reconsitituted with methanol. For using GC-MS analysis, a fraction of 10 μL was mixed with 1.0 μL acetic anhydride reagent and directly injected to GC-MS system to obtain on-line derivatization. For using UHPLC-QTOF-MS analysis, a fraction of 2 μL was directly injected into UHPLC system.. The detection limits with GC-MS was 0.01 - 0.02 ng/mL. Intra-day and inter-days precision (% RSD) for four analytes were less than 8 %; the detection limits with UHPLC-QTOF-MS was 0.12-0.25 ng/mL, the RSD for nine analytes were less than 10 %, indicated that these methods show a good stability and reproducibility. In real samples, MeP、EtP、PrP and BuP were detected in most urine samples by GC-MS, the total concentrations ranged from 0.3 to 124.5 ng/mL for male; and from 27.6 to 246.8 ng/mL for female. Female urine samples showed higher total concentrations for the four target parabens, which may indicate higher exposure due to lifestyle. Moreover, small amount of PeP and HxP was detected in one urine sample by UHPLC-QTOF-MS, this results indicate that some disabled and higher toxicity parabens were in use in Taiwan.
Guo, Sheng-RU, et 郭勝儒. « none ». Thesis, 2017. http://ndltd.ncl.edu.tw/handle/02196946011527866379.
Texte intégral國立中央大學
化學學系
105
Vinyl chloride is the monomer of polyvinyl chloride (PVC) and is commonly addressed as vinyl chloride monomer (VCM) in the relevant industries. VCM is both liver-toxic and carcinogenic, and with its precursor of 1, 2-dichloroethane (EDC), are produced in large amounts in Taiwan. For instance, the annual production of VCM is greater than 1.25 million tons from the top two producers. Because of the high volatility of both VCM and EDC, fugitive emissions from leaky components of flanges, gaskets, pumps, pipelines, etc. are widespread. Monitoring of these two compounds of high toxicity in ambient air is essential to the health and safety of the general public and factory workers. Despite of the necessity in monitoring, the current analytical methods for these two compounds are off-line methods such as the U.S. TO-15 and NIEA 715 of Taiwan EPA. In these off-line methods, air samples are collected with canisters and analyzed by gas chromatography-mass spectrometry (GC-MS). The major drawback of these off-line GC-MS methods is the lack of capabilities to capture peak emissions for the exposure assessment of the worst-case-scenario. As a result, in this study, an on-line method by coupling the thermal desorption (TD) technique with GC-MS method was developed to perform unattended continuous monitoring of ambient VCM and EDC in the field. To cope with the interferences brought upon by the high humidity in ambient air which often times led to ice clogging in the sorbent trap as well as high noise levels in MS detection, a water-removal stage prior to TD was developed with only a minor modification in the original TD configuration. The resulting TD-GC-MS method was tested to show precision in the range of 0.98 – 9.37% (RSD) for 57 compounds listed in NIEA 715. Of the 57 compounds, VCM showed a precision of 5.29%, linearity (R2) of 0.99 and method detection limit (MDL) of 0.024 ppb. In the field experiment during the period 2016/11/10 - 11/20,the maximum concentration of VCM was 1.28 ppb (v/v) occurred on Oct. 11, when the direction swept from northeast to northwest. For the rest of the measurement period, VCM concentration was either small (below 0.2 ppbv) or below the detection limit.
Hsu, Po-Yu, et 徐伯毓. « none ». Thesis, 2016. http://ndltd.ncl.edu.tw/handle/70126744668821025236.
Texte intégral國立中央大學
企業管理學系
105
As the population aging in the world, gerontology-related researches gradually increases and almost focuses on specific fields. The objective of the study was to conduct a descriptive and trend analysis, network analysis and text mining on gerontology-related researches published after 2000, and provide a breadth of understanding from the development of gerontology. The data used in this study were collected from the journal papers listed in Social Sciences Citation Index. Furthermore, the studies which its times cited rates were ranked as top 200 would be treated as influential studies in order to understand the correlation between different areas. Overall speaking, the research of gerontology-related had increases significantly after 2000 whereas the research which included into top 200 was mainly published before 2007. U.S. was the most productivity country from the analysis of the overall and top 200 studies, where health-related words show frequently in Author Keywords and KeyWords Plus. The most productive research subfields was psychiatry and psychology in overall analysis and top 200 analysis, respectively. The study then conducted a co-words, bibliographic coupling and co-citation analysis on the influential studies. This study chose top five Author Keywords and abstract of top 200 to conduct a text mining. Through text mining, this research can be more widely understand the scope of popular keywords, and related terms or keywords in different areas can be used by follow-up researchers. The overall analysis provides the follow-up researchers to enter the field with a breadth of knowledge for gerontology. It also gives researchers who have long been committed in this field a different approach of research trends.
Kang, Ya-Wen, et 康雅雯. « none ». Thesis, 2017. http://ndltd.ncl.edu.tw/handle/97218303447751683322.
Texte intégral國立中央大學
財務金融學系在職專班
105
The most stressful work, Whether it is on Wall Street or in the entire financial services industry are far ahead, But the nature of the stress varies with the level. While the bully who think that such as superior,Always above the pride of others,so that many vulnerable, kind people are no way to be insulting,and this situation is not only occurred in the mind is not yet mature campus, and even have entered the community for many years of office workers are also possible Suffered a variety of different forms of bullying. Taiwan researchers have little focus on financial practitioners were bullying behavior, employees at the same time to bear the performance of financial institutions, but also bear the workplace in the dominant and even hidden in the bully life. This study is based on the position of financial practitioners, and the research on the correlation between the victim's own personality traits and the influence of personal performance, and the use of Taiwan's financial industry practitioners as samples to try to discuss the "bullying"、"Personality traits" and "employee performance ". The sample used in this study is Taiwan financial practitioners, including banking, securities, insurance, investment, etc., a total of 142 samples, and interviewer data analysis. Researchers try to integrate the effects of bureaucratic and personality traits on the performance of employees in various financial institutions, and are used as a reference for psychologists and bullying researchers as follow-up studies. Keywords: personality traits, bullying, performance, labor, finance
Tu, Kuo-Lun, et 杜國綸. « None ». Thesis, 2017. http://ndltd.ncl.edu.tw/handle/19654512607621704741.
Texte intégral國立中央大學
資訊工程學系在職專班
105
Data-Matrix two-dimensional barcodes present extensive information within a compact area. Data-Matrix barcodes have been widely used in automobile, aerospace, semiconductor, and electronic components. However, the Data Matrix barcode readers currently available on the market use multiple image preprocessing methods for identification of barcodes that appear fuzzy, unevenly lit, distorted, and otherwise unrecognizable; with such systems, failed identification often needlessly wastes computational time. Poor image quality or a large amount of unnecessary high-frequency information can hinder the barcode recognition and consume a substantial amount of time. In addition, unrecognizable barcodes cannot be predicted in advance, resulting in wasted time. This study presents a Data-Matrix two-dimensional barcode recognition system based on the mainstream open source software libdmtx, which uses Sobel filter edge detection to obtain the barcode along the positive and negative tangent lines. To address the shortcomings of typical systems, a novel classifier is applied in this study to predict whether a given barcode can be successfully recognized. This prevents cumbersome image preprocessing and subsequent recognition steps for low-quality barcode images, thereby saving computational time. Furthermore, during the image preprocessing phase, a discrete wavelet transform approach is employed to enhance image quality and improve barcode recognition, thereby improving both speed and accuracy of system operations.
Chang, Che-Wei, et 張哲偉. « none ». Thesis, 2017. http://ndltd.ncl.edu.tw/handle/39401885748022166582.
Texte intégral國立中央大學
機械工程學系
105
The demand for Electric Discharge Machining(EDM) is increasing year by year in the industry. Because of EDM can effectively solve the problem of processing materials such as high hardness and heat resistance. However, EDM will bring about defects in surface defects and poor surface quality that still can not find an effective way to solve in the industry. Previous studies have found that processing will get a better surface roughness when the EDM fluid in a specific turbidity. Therefore, in this paper, we design a closed loop system that use of optical turbidity sensor and a cycle filtration system combined with Arduino microcontroller and LabVIEW to realize Real-time turbidity monitoring and control. Expected to achieve the goal of improving the surface roughness in EDM by controlling the turbidity of the EDM fluid.
Lu, Dong-Han, et 呂東翰. « none ». Thesis, 2017. http://ndltd.ncl.edu.tw/handle/28050356056646596855.
Texte intégral國立中央大學
機械工程學系
105
Recently, research of active magnetic bearings has been widely applied in industry. It’s non-contact characteristic of magnetic levitation technology without physical friction and abrasion. Therefore, active magnetic bearings have been widely implemented, such as engineering industry and biomedical application. For example, turbine engine [1], vacuum pump[2], high-speed spindle[3], and so on. Rotating mechanical umbalance causes severe system vibration. The synchronous vibration caused by eccentricity of the rotor is the major excitation source, when rotating at high speed. As the operating speed increases to certain speed, the centrifugal force makes the bearing vibrate larger than the size of air gap, the rotor and the emergency bearing will collide with each other. This paper aims to develop unbalanced compensation of active magnetic bearings base on a digital processor. First, inductive displacement sensors and PD controller are used to levitate the maglev bearing. A generalized notch filter is used to eliminate the synchronous unbalance operating and implement the auto-balancing control of the active magnetic bearing, when the magnetic bearings are operated to certain speed.
Wang, Yi-Hsuan, et 王以萱. « none ». Thesis, 2017. http://ndltd.ncl.edu.tw/handle/33057877208864952395.
Texte intégral國立中央大學
高階主管企管碩士班
105
This paper aims to explore and analyze the competition strategy of the notebook computer industry in Taiwan, taking C Company as a case and combining with the characteristics of the overall market demand of the mainland, and discussing the status quo of the industry in which the company performs the notebook computer marketing activities on the mainland, the internal conditions and the external Competitive environment and so on. Using SWOT analysis and 4P marketing theory, C company to take the marketing strategy (such as products, prices, access, promotion) and other aspects of a comprehensive analysis to find C company notebook computers in the mainland market competition has the advantage To help Taiwan's notebook enterprises in the new market environment, the use of its own advantages to adjust its strategy in the market competition in order to help Taiwan's notebook enterprises in the new market environment, the use of its own advantages to adjust its strategy in the market competition To enhance its overall competitiveness.
Chiu, Jung-Ching, et 邱榮慶. « none ». Thesis, 2017. http://ndltd.ncl.edu.tw/handle/00527707096858223920.
Texte intégral國立中央大學
光機電工程研究所
105
This thesis is mainly concerned with the implementation of control algorithm the active magnetic bearing. In the development of hardware part, we use the commercial active magnetic bearing platform, and design a robustness Proportional- Derivative controller. Then the rotor is levitated and run by the PD controller. When the operation speed reaches the target, we implement the control algorithm to eliminate the centrifugal force, that is, the generalize notch filter compensator is used to the control system. Finally we eliminate the centrifugal force, and realize the active magnetic bearing auto-balance. The TMS320F28335 digital signal processor is used as the core processor of active magnetic bearing. The position sensor signal is fed back to the TMS28335, after the control algorithm operation, the TMS28335 outputs the control current to electromagnetic coil and executes the magnetic levitation.
Wang, Ming-Ze, et 王銘澤. « none ». Thesis, 2017. http://ndltd.ncl.edu.tw/handle/48079776711356317949.
Texte intégral國立中央大學
土木工程學系
105
This paper is to investigate the resource’s reuse technelogy aiming at the waste produced by the domestic solid biofuel boiler plants and burning solid bioful factories. First, it will focus on the resource recycling and research areas according to the norms of public works and the national CNS norms. Then, five types of biomass and waste fuel which contain lump coal , waste wood , wood pellets , palm shell , waste mushroom packages…etc. are selected according to the boiler fuel classfication . After that, based on the solid biofuel fly ash and solid biofuel bottom ash produced by the above five types of fuel, this study will conduct basic physical property and chemical property testing between civil materials to inrestigate the characteristics of the materials. In order to achieve the maximum benefit of resource cycle , this study will adopt the different reuseable technologies and conduct the appropriate evaluation according to the basic test results and the nature of the materials. The technologies used to proceed the civil material reuse conducted in this study include the “Controlled Low Strength Material(CLSM)”, “artificial aggregate” and the “Compressed concrete paving units”. To comply with the environment protection stondard and the engineering laws and regulations, this study will explore the reuse technologies regarding to the above materials , chemical property and the engineering characteristics. In addition it will evaluate the reuse of the solid biofuel fly ash and bottom ash and its benefits. The results show that the solid bofuel ash used in this study has the characteristics of high water absorbency and high residual caarbon. The cement mixed with cement mortar has the effect of delaying the condensation and decreasing the strength . There fore the use of grinding technalgy can make the solid biofuel fly ash increase its reuse value Moreover, it can be applied on the civil engineering materials after crushing due to the large particles and lose structure of solid biofuel bottom ash.
Hu, Chia-Ming, et 胡家銘. « none ». Thesis, 2017. http://ndltd.ncl.edu.tw/handle/93225162053586283691.
Texte intégral國立中央大學
土木工程學系
105
Due to the wide range of concrete in radioactive waste disposal sites, the use of cement materials is very important, especially when the groundwater penetrates into the concrete. The Ordinary Portland Cement (OPC) releases the pore fluids of the pH 12-13. In the high pH environment, the pore water leakage after the encounter buffer material, it will make the buffer material with the expansion of the main components of montmorillonite dissolution rate which increases the pH. Therefore, the use of low-alkali cement material after the pozzolanic reaction, the consumption of calcium hydroxide solution (CH), will reduce the pH value that ensure the buffer material are safety. In this study, the micro-characteristics, engineering properties and durability of the same cementing ratio of cement paste, mortar and concrete were replaced by low pH cement silica and fly ash. According to the references, the measurement of pH method are found that Ex-Situ leaching method is established for laboratory testing whichis easily and capabilities. To explore the use of different mineral admixture of silica fume and fly ash replace of cement, it will reduce the pore fluids of the pH value effectively. The results show that the addition of Pozzolan material to the cement can reduce the pH value of the pore solution by adding silica fume. To achieve the requirements of the concrete plug sealing, it needs to control the amount of cementitious materials, when 40% silica fume replace of cement, the pH of mortar and concrete samples in the 90-day is lower than 11. Because of the silica fume is more expensive than fly ash and when the more silica fume is added, the workability is in bad condition, it needs add some plasticizer to improve the workability. Therefore, the silica fume and fly ash were replaced by cement weight 35 % and 20% respectively, it can achieve the requirements of quality of low pH concrete plug sealing.
CHUEH, LI-EN, et 闕立恩. « none ». Thesis, 2017. http://ndltd.ncl.edu.tw/handle/85393838939631376715.
Texte intégral國立中央大學
土木工程學系
105
Slag fine aggregates are by-products of electric arc furnace steelmaking. After the slag fine aggregates are pre-treated, they can replace natural fine aggregates in some cases. In this study, the researcher used slag aggregates, water quenched stove powder, sodium hydroxide solution, and sodium silicate solution (water glass) to activate the slag cementation activity. The objective was to explore the effects that the alkali activated furnace powder cementing material have on the new mix and the hardening properties under different alkali equivalent volumes, alkali modulus ratios, and water-cement ratios. In this study, the researcher referred to the curing environment of ASTM C1260 to soak the slag aggregate specimen in 80 ℃ 1N concentration NaOH solution. After 14 days, the researcher removed the test specimen and measured the amount of expansion. Finally, the researcher used the preferred alkali activation ratio to produce high-pressure concrete bricks and investigate the performances of the alkali activation technology for recycled products. The study results indicated that: (1) The condensation time of alkali activated mortar would shorten as the alkali equivalent volume is increased. (2) When the alkali activated mortar of the slag fine aggregates has the alkali equivalent volume of 5% and alkali modulus ratio of 0.75, the compressive strength is greater than the cement mortar; the higher the alkali activator concentration, the better the compressive strength development for the mortar. (3) The alkali activation technology can have an expansion suppressing effect for the specimen soaked in the 80 ℃ 1N concentration NaOH solution. (4) When slag aggregates are used to make concrete bricks, the bricks would achieve CNS 13295 specification C-grade compliant if the alkali equivalent volume is 6% and the alkali modulus ratio is 1.75.
Chen, Wen-Jou, et 陳文柔. « none ». Thesis, 2017. http://ndltd.ncl.edu.tw/handle/82467449579606489403.
Texte intégral國立中央大學
大氣科學學系
105
Rapid-Intensification (RI) typhoon forecast remains a critical challenge, it usually causes severe damage all at once. According to the previous research, a critical mechanism for reducing rapid-intensifying typhoons was “the positive feedback” occurred in or near the eyewall region. That is, for low-level convergence enhances upward flow motion, latent heat then releases to surroundings causing a warm-core in mid-upper-level. Warm-core structure helps to maintain typhoon intensity; then divergence in upper level pulls lower flow to transport updraft at the same time, and it finally forms second circulation that intensifies typhoons. In this study, we conducted a 48-hour data assimilation and a 72-hour forecast experiment by using GSI 3D-Var v3.3 data assimilation system and WRF model 3.6.1 version. An rapid-intensifying typhoon Megi(2010) was chosen to analyze the RI processes from two sets of experiments, i.e., from the assimilation of GTS only and GTS with RO data. These two experiments will used to evaluate two different atmospheric states in the initial fields and followed typhoon forecasts in the RI stages. Some important RI mechanisms were analyzed, such as convergence, vertical velocity, wind shear, 700 hPa relative humidity and temperature anomaly. GTS+RO experiment gave positive impact to the typhoon simulation. Sensitivity tests show that RO profiles below 500hPa played an important role in the improvement of intensity; Moreover, assimilating lower number of RO profiles will degrade the forecast performance but not in linear relationship with the used RO data.
Chaung, Qun-Ling, et 莊坤霖. « none ». Thesis, 2017. http://ndltd.ncl.edu.tw/handle/87355364429857834368.
Texte intégral國立中央大學
化學學系
105
In this study, three new hydrophilic monomers were synthesized and a new series of anion exchange membranes were derived from the last monomer. First, NB-DCImI was synthesized. However, due to the steric hindrance in the monomer structure, only one imidazole group can be quaternized. The second methylation of imidazole group was not successful. Secondly, new hydrophilic monomer BCIm-COH bearing two imidazole groups was successfully synthesized. However, we found the ether-linking hydrophilic monomer do not possess good chemical stability in the presence of NaOH/DMSO solution. Finally, new hydrophilic monomer NB-CImI-4 are developed which NB bearing a butyl imidazole group. The new developed monomer exhibits a very high chemical stability at 60 C for two weeks in the presence of NaOH/DMSO solution. Polymer PNB-CIm-4 was prepared via ring-opening metathesis polymerization (ROMP) of the new developed hydrophilic NB-CImI-4 and hydrophobic NB-Hex. Via changing the equivalence of these two NB monomers, the hydrophilic and hydrophobic ratio of the random copolymer can be controlled. Currently, PNB-CIm-4 (R-50) shows ionic conductivity of 0.03 S/cm. Highly hydrophilic PNB-CIm-4 (R-90) exhibits ion conductivity up to 0.074 S/cm.
Huang, Chien-Jung, et 黃健榮. « none ». Thesis, 2017. http://ndltd.ncl.edu.tw/handle/13049551609887730846.
Texte intégral國立中央大學
資訊工程學系在職專班
105
In order to shorten response time without compromising the confidentiality of private data, fog calculation or marginal computing has become a new research topic, in the post-cloud era, the traditional network of objects with cloud computing being the core will face difficulties in meeting the standard of the real-time terminal services with limited bandwidth. This study designed a network of objects gateway with three MCU cores, structured as a master–slave microcontroller system. The three cores are the communication management engines, and uses a MQTT Client and cloud service layer for bridging transmission. The device management engine uses a blue tooth device to bridge the transmission with the sensing layer. The database management engine is responsible for the management of data sorting to allow database management to be equipped with efficient data searching ability. As a result, the required information communication and data management and analysis can be transferred from the cloud to the gateway end. In this way, the problem of immediacy and privacy of communication using the device can be solved. The experimental results have also shown that our three-MCU cores system has obvious advantages in the transmission efficiency and stability compared with the single core gate.
Lin, Wei-Han, et 林緯瀚. « none ». Thesis, 2017. http://ndltd.ncl.edu.tw/handle/19962747170812670591.
Texte intégral國立中央大學
機械工程學系
105
In this study, Ti-6Al-4V titanium alloy weldments with butt joint were produced by electron beam welding (EB welding). Several tests including microhardness, tensile, constant amplitude fatigue and variable amplitude fatigue were performed. The experimental S-N curves were compared to the fatigue design curves recommended by the International Institute of Welding, American Welding Society. Two mean stress correction methods, Goodman and Gerber, were evaluated. For electron beam welding joints, the highest microhardness occured in the fusion zone. Both the broken positions of tensile and fatigue specimens were in the base metal. Electron beam welding butt joints of Ti-6Al-4V alloy illustrated higher fatigue strength as compared to the fatigue design curves of AWS D1.9 standard. The results showed that the fatigue of electron beam welding specimens under the transmission history and bracket history could be predicted using the Goodman mean stress correction method
Dai, Ming-Shen, et 戴銘伸. « none ». Thesis, 2017. http://ndltd.ncl.edu.tw/handle/76068815013442353753.
Texte intégral國立中央大學
機械工程學系
105
In order to satisfy the needs of electric energy, the capacity of the wind turbine is getting larger. It resulted in a larger weight and a heavier operational load for the wind turbine. The cost will increase and the life cycle will decrease if the wind turbine is operated with a heavy load. This study investigated the stresses of a Vestas V80-2.0MW wind turbine tower. The author applied SolidWorks software to rebuild the V80 wind turbine tower model. Then, the flow field analysis of wind turbine model was carried out by using the Fluent software. We simulate the wind turbine under different conditions of operation, then the results of the fluid analysis were imported into the fluid-structural analysis to find the stress and strain distribution of the wind turbine. The ANSYS software was utilized to study the stresses of the tower under steady and transient operations. The results showed that the blades are subjected to a greater force than the tower at different wind speeds. The tower wouldn’t fail under the normal operation or the special wind speeds which were defined in IEC 61400-1 specification. In different extreme wind speed cases, the tower has the maximum stress at the flange bolts of the middle tower. In the transient simulation, the maximum equivalent stress of the tower is smaller than the yield Strength of the tower in the cut-out wind speed of the emergency shutdown. The operation of the wind turbines doesn’t induce resonance of the tower in rated speed.
Yeh, Jih-Hung, et 葉日宏. « none ». Thesis, 2017. http://ndltd.ncl.edu.tw/handle/45615914523583187080.
Texte intégral國立中央大學
環境工程研究所
105
Hazard management is the key factor in accident prevention. And hazardanalysis is the first step of hazard management. To implement effective hazard management, manufacturing processes related personnel and activities must be first taken into consideration followed by evaluation of the effectiveness of management approach.. Laws and regulations or most of the guidelines mention the importance of hazard analysis and management system. But there is no reliable and feasible methodology for hazard analysis and management prior to the construction and operation of a manufacturing process. Therefore, this study aims to developa systemsapproach for prior-commissioning hazard analysis and methods of management. From the construction and operation of a manufacturing process, break down the manufacturing process progressively to physical layers or components to confirm the mechanism of hazard creation and estimate the possible level of consequences and draft precautionary measures. Decision trees can be used to estimate each precautionary measure’s benefits to offer possible options to decision makers. This will reduce the influencing degrees of hazard through emergency response if hazardous events occur.After emergency response, incident investigation can be executed to identify the root causes of the incident and to design the corrective actions. This study uses the manufacturing process of steel box girder as an example. Utilization of the proposed method can analyze the hazard factors which have probably existed in the manufacturing process for quite some time. The analysis results can be used to design the management approaches prior to, during and after the occurrence of a hazardous event. The proposed methodology can also be used to analyze the adequacy of necessary contingency resources and to investigate the root causes of incidents in order to design and implement corrective actions and to reduce the consequences of hazardous events.
Li, Kun-Che, et 李昆哲. « none ». Thesis, 2017. http://ndltd.ncl.edu.tw/handle/89000879974067396635.
Texte intégral國立中央大學
土木工程學系
105
Dip slope sliding is the most occurrence of slope disaster in Taiwan and the geology of Taiwan mostly consists of sedimentary rocks like sandstone and shale, both are very weak rocks. In recent years, the rainfall intensity enhancement and the influence time lengthened, had the severe influence on the geology of Taiwan. For instance, water easily seeps through aperture of rocks and reduces rock strength, or increases the pore water pressure thus decrease the shear resistance of soil. Due to above reasons, slope easily to produce slide and mudslide. In this study, the discrete element method is used to simulate the sliding process and the deposition behavior of different types and scale slopes under different water level conditions, and discusses the effect of floating in numerical simulation. The numerical model is based on the centrifuge physical test model of Zeng, W. J. (2015) and Lin, Y. J. (2016)’s thesis. The numerical models are carried out to modify the code of the weakening zone, and the results are compared with the physical test results. The aim is to integrate the parameters used by the three numerical models, including the dry friction coefficient and the wet friction coefficient which is reduced by water’s influence. After number of test, we decided to adopt the value of dry friction coefficient is 0.7 and the wet friction coefficient is 0.3, and using the discrete element method to simulate at different gravity. The analysis items include the sliding process of the slope, the stacking result, the displacement of each particle and the velocity of particle. In this study, the sliding failure mode of the dip slope will be different according to the rock structure. The dip slpoe which is interbed layer and the angle of layer is 30 degrees is "remove the toe of slope sliding mode". The dip slpoe which is interbed layer and the angle of layer is 60 degrees is "slope bulging sliding mode". The dip slpoe which layer is alteration and the angle of layer is 60 degrees is "rock fall mode". It is hoped that the simulation results of this study will provide to the disaster prevention center to reduce the disaster caused by sliding slop.
Liao, Ming-Chieh, et 廖明傑. « none ». Thesis, 2017. http://ndltd.ncl.edu.tw/handle/75744791667725602928.
Texte intégral國立中央大學
土木工程學系
105
Because the rock mass is often accompanied by the joint, the overall shear strength of the rock mass is affected not only by the strength of the material itself, but also by the existence of the joint. The influence of the existence of rock joints on the shear strength of rock mass has been proposed by Barton to estimate the shear strength of rock mass under the influence of joint. Where the joint surface roughness is an important influencing factor, and the joint roughness coefficient (JRC) is usually used to represent the roughness of the section. Barton (1977) proposed the visual comparison method for the earliest assessment of the JRC method, but because of this approach is more subjective, in recent years, many scholars have proposed numerical quantitative objective way to assess JRC. Due to different theories or assumptions in the assessment of JRC will cause some overestimation or underestimation, in this study, 86 rock joint sections (known as JRC) were collected and digitized and analyzed statistically. It is found that the elevation difference of the joint surface is normal distribution, and the standard deviation of the elevation difference is highly correlated with the JRC value. In this study, a new set of new rock joint sections was generated by the above parameters and use different JRC evaluation method for JRC calculation and comparison, and finally the JRC assessment of the distribution of the value of the trend of the proposed recommendations. In addition, we use the PFC2D to simulate the unconfined compression test of rock and the basic friction angle of rock joint direct shear test After obtaining the rock mechanics parameters of this model, the numerical model of the direct shear test was established for one of the randomly generated rock joint and the standard profile proposed by Barton. The results obtained by this numerical model are compared with the empirical formula of shear strength proposed by Barton (1977). The results show that the shear mechanics behavior of the randomly generated joints is in accordance with the Barton standard profile and the empirical formula.
Chou, Mei-Hsiu, et 周美秀. « none ». Thesis, 2017. http://ndltd.ncl.edu.tw/handle/44331598971122079161.
Texte intégral國立中央大學
化學工程與材料工程學系
105
We have developed a transparent, easy cleaning and durable hydrophobic coating for the glass surface. Such surface is very desirable for touch screens that have become an essential part of our daily life. For practical applications, the coatings should also be strongly adhered to the substrate and should resist at least a few thousand cycles of steel-wool scratching without losing its hydrophobicity. Previous easy-cleaning surface relies on the hydrophobic behavior of poly-fluorocarbon coupling agents, which will be banned in European Union nations soon. Masheder et al. have recently developed a fluorine-free zirconiumcarboxylic hybrid coating that exhibits excellent dynamic oleophobicity and anti-fingerprint property. Unfortunately, the durability of this coating is far inferior to that of the current commercial products.
TING, KAO YU, et 高雨婷. « none ». Thesis, 2017. http://ndltd.ncl.edu.tw/handle/82641800349251692588.
Texte intégral國立中央大學
化學學系
105
This article is divided into two parts: The first part: There are hundreds of billion tons of plant wastes generated every year. Scientists tried to separeate and refine to make those wastes more benefit. Lignin is one part of lignocellulose and consisted of aromatics. We expected to find out a effective way to cleave lignin into many different small molecules and then separate them very well. In order to clarify the mechanism of lignin cleavage and to find out the better conditions, many scientists using lignin model compounds in the cleavage reaction at first, especially beta-o-4 model compounds because beta-o-4 linkage is the most abundant bonds in lignin. Ketone-form beta-o-4 which the secondary alchohol functional group was oxidized can promote the cleavage of beta-o-4 bond, so starting our research on this kind model compounds, we found out many mild conditions to break them down to small molecules. We developed a new approch to break down beta-o-4 model compounds to phenol and benzoic acid with only equivalents of KOH under aerobic condition in acetonitrile at room temperature. We also found that reactions could work effectively by heating up the temperature of reaction to reflux temperature or adding Cu(II) catalyst. Finally, we proposed the mechnism of the reaction and proved by theoretical calculations. The second part: The reaction of C-N cross coupling is play a important part of organic synthesis. Among them, there had already many researches on the C-N cross coupling by copper-catalyzed between aryl halides and amines, but the reaction mechanism is not yet clear. In this article, we presented the new evidence of the mechanism of the C-N coupling reaction for the coupling system of HNPh2 / iodotoluene / CuI / 1,10-phenanthroline, and reacted with copper(I) and copper(II) catalysts respectively to compare their differences in reactivity.
Tseng, Tsung-En, et 曾從恩. « none ». Thesis, 2017. http://ndltd.ncl.edu.tw/handle/48751617563980747128.
Texte intégral國立中央大學
太空科學研究所
105
CIP (Compact Ionosphere Probe) is the only one science payloads on the INSPIRESat-1. The purpose for CIP is measuring ionophere parameters. Including the ion concentrations、ion velocity、ion temperature and electron temperature. The CIP is seted up in the 3U cubesat. Due to the space limit, it have to minimum the sensor volume into 1U space. In the CIP interior, it is assembled by the three PCBs. The thesis is focus on the development and design of the third PCB. The third PCB is called Power Management Unit (PMU) . The main purpose of the PMU is to let CIP normally operation by convertering the satellite power and distributing the power to the every components in the CIP. PMU also be integrated into the CIP, too. The PMU controls the power system of the CIP. It must have the protection device to avoid the components damage because of inrush current or SEL (Single Event Latch-up) . The circuit design is using the NI Multisim software and the layout is using the NI Ultiboard software. Refering the specification of every components, end then designing the circuit that is correspond to function requirement of the PMU. Finally, combinating the three PCBs and deploying in the plasma enviroment measure the plasma to verify the design and function normally.
Liao, Chao-Wei, et 廖朝偉. « none ». Thesis, 2017. http://ndltd.ncl.edu.tw/handle/28704840898438288998.
Texte intégral國立中央大學
光電科學與工程學系
105
The principal of design optical telescope will be introduced in this dissertation. CODE V optical software is used for helping us to design eyepiece lens and objective lens, both of lens are combined into a telescope by using the positive focus system of the Kepler telescope, and the Roof-Pechan Prism is added to the telescope system, reducing the overall length of the telescope by 11.56%. In the prism design, Prior to the plate glass to simulate the optical path length in the prism, moreover it uses plate glass and objective lens to optimized at the same time. Finally, the entire telescope system design will be completed by using Roof-Pechan Prism replacing plate glass. Besides, the optical system is considering that the RMS, Strehl ratio, optical distortion and lateral color to determine the design quality. the standard of RMS OPD is less than 0.07λ, Strehl ratio is greater than 0.8, optical distortion is fewer than plus or minus 2%, and lateral color is less than 25μm. In the lens process, the coefficient of centering and thickness ratio are separately higher than 0.1 and 0.33.
Chien, Wei-Hsien, et 簡維憲. « none ». Thesis, 2017. http://ndltd.ncl.edu.tw/handle/05846968228380958979.
Texte intégral國立中央大學
光電科學與工程學系
105
This paper focuses on the three-band surveillance lens design, which can operate in the near infrared band to obtain a clear image quality, and the image sensor used can sense the visible light band to near infrared light band. This lens can be used at any time, any weather and any environment, as the surveillance of visible light to near infrared light band. In this paper, the lens design analysis is mainly for visible light to near infrared light band, visible light band and near infrared light band. By applying different image sensors to design a lens group, to analyze the image quality and tolerance, and finally, to analyze the group transmission of the lens, so that the three-band surveillance lens in any environment can obtain a better image quality.
Yi-ChengChang et 張毅政. « none ». Thesis, 2017. http://ndltd.ncl.edu.tw/handle/50729562402790917871.
Texte intégral國立中央大學
光電科學與工程學系
105
The design of portable microscope was introduced in this thesis. There are three parts in this design; an objective lens, a prism, and an eyepiece. Finally, combining objective lens, pechan prism and eyepiece to form an optical system. The objective lens’s magnification and NA are abbreviated as 10X/0.25. The selection of Prism is Pechan prism. The eyepiece magnification is 20X. By lens and prism combining, we can design a 200X microscope system. It can be operated individually to observe the object. The objective lens and the prism are built in the same optimization process. The length of objective system is reduced from 40.25 mm to 22.00 mm by the design of pechan prism. The length of the objective system is reduced by 45.34%. Finally, the total length of the microscope system is about 66.23 mm which achieves the purpose of being portable. In addition, Strehl ratio of an optical system is a diffraction limited system while the value is higher than 0.8.Therefore, the required microscope system’s Strehl ratio is higher than 0.8 to meet the image quality.
Shen, Yu-Sheng, et 沈裕盛. « none ». Thesis, 2017. http://ndltd.ncl.edu.tw/handle/84751926732099850862.
Texte intégral國立中央大學
照明與顯示科技研究所
105
I propose designing a 60 mm single hole telescope with the capability of 60X magnification power. The telescope system consitsts of a object system and a eyepiece system. Both systems are to be designed separately and assembled together afterwards. The maximum incident angle, focal length, entrance pupil diameter of the object system is 0.55 degree a half of FOV, 350 mm, and 60 mm respectively. The maximum exit half angle of view, focal length, exit pupil diameter, and eye relief, and of the eyepiece system are 29.941 degree, 5.833333 mm, 1 mm, and 14.695257 mm respectively. The usage of prisms makes observation via human eyes easier. By using geometric optics to obtain the required refractive index of prism, then analyzing and calibrating the wavefront error, optical distrotion,lateral color and relative illumination of to create both systems, the systems are then to be combined to create the telescope capable of 60X magnification. Afterwards, determine whether the image quality of the final product fits the standards via analyzation.
Chen, Yi-Jun, et 陳怡君. « none ». Thesis, 2017. http://ndltd.ncl.edu.tw/handle/09058192105528075667.
Texte intégral國立中央大學
化學工程與材料工程學系
105
2-phenylethanol is widely used in the cosmetics and perfumery for fragrance modification with rose-like fragrance. Every year about 10000 tons of 2-phenylethanol are produced worldwide, the most of which through chemical synthesis. The chemical synthesis of 2-phenylethanol can be done by Friedel-Craft reaction. Though inexpensive, these processes are disadvantaged by low selectivity for the desired product and accompanied by the formation of toxic by-products. This makes the chemical production of 2-phenylethanol detrimental to the environment and health. Therefore, legislations of the US and EU have restricted the use of chemical 2-phenylethanol in cosmetics and food products. Therefore, how to replace the 2-phenylethanol by the chemical synthesized has become the trend of industrial development through the lower cost and the principle of protecting the environment, such as the use of microbial fermentation is becoming an alternative platform. Yeast fermentation has become the focal point of research effort utilizing the Ehrlich pathway wherein the L-phenylalanine is converted to 2-phenylethanol. However, 2-phenylethanol and ethanol have common inhibitory effect for yeast fermentation. Many studies had proved that product can be removed through in situ product removal techniques and the yield of product will increase. In this study, owing to the sponges have the hydrophobic property, it can adsorb 2-phenylethanol. So, we use the PDMS sponges to remove 2-phenylethanol, in order to reduce the inhibitory effect. By using the PDMS sponges, the yield of product can be increased and the extracted energy cost can be reduced.
Yeh, Yi-fen, et 葉怡芬. « none ». Thesis, 2017. http://ndltd.ncl.edu.tw/handle/46191974363766888872.
Texte intégral國立中央大學
化學工程與材料工程學系
105
In oriental culture, mushrooms has been used as health foods and home remedies for thousands of years. In several edible mushrooms, Agaricus blazei Murill was considered one of the most important edible and medicinal mushrooms native from Brazei. We also called it Agaricus brasiliensis. Many studies had proved that the Agaricus blazei Murill have strong immunomodulatory and health care functions, such as immune-enhancement, oxidation resistance, lower blood lipids et al. Recently, Agaricus blazei Murill is fascinating natural source for obtaining bioactive materials such as polysaccharides, beta-D-glucan and ergosterol. Among these chemical components, its polysaccharides with antitumor activity have attracted most attention. Therefore, the yields and functionality of bioactive properties produced by liquid fermentation are highly depend on the culture conditions and environment parameters, such as pH, medium compositions, culture temperature and aeration rate et al. Culture temperature is the one of the most important parameters influencing the production of bioactive properties and the cell growth. So, in my research I choose two different fruiting time of Agaricus blazei Murill to study on the effect of culture temperature ranging from 20℃ to 40℃ on cell growth, production of bioactive polysaccharides and beta-D-glucan. Agaricus blazei Murill were evaluated via five culture temperatures in step of 5℃ in a liquid fermentation, in order to optimize liquid fermentation condition of Agaricus blazei Murill for highest amount of biomass, bioactive polysaccharides and beta-D-glucan production and to compare what different between two strains of Agaricus blazei Murill. According to the results, use the two-stage temperature to increase the production of beta-D-glucan content.
Lo, Yu-Cheng, et 羅雨承. « none ». Thesis, 2017. http://ndltd.ncl.edu.tw/handle/12420830074422676253.
Texte intégral國立中央大學
化學工程與材料工程學系
105
In today's society, lactobionic acid is a kind of organic acid which is widely used in human life, it finds extensive applications in the fields of food, cosmetics, pharmaceuticals and biomedicine. It could be used in so many different fields, mainly because of its excellent biocompatible, biodegradable and antioxidant properties. Most of the current methods of producing lactobionic acid are produced by chemical synthesis, but the synthesis processes use harmful metal catalysts. However, in recent years, a method for producing lactobionic acid has been discovered by microbial fermentation. This method is producing lactobionic acid from whey by Pseudomonas taetrolens. Whey is the by-product produced in the manufacture of dairy products. About 30% of whey remains underutilized, most ending up being employed as animal feed, spread on agricultural land as fertilizer or even as waste. Producing lactobionic acid from whey by microorganism instead of using the chemical synthesis method can avoid the use of harmful catalysts. Furthermore, the microbial fermentation produces high value-added products from inexpensive feedstock such as polluting waste, so the cost of production is relatively low, and is more environmental friendly. It is consistent with the concept of sustainable development. In microbial fermentation procedures, environmental temperature will greatly affect not only the physiological status but also the behavior of microorganisms. Ergo, the aim of this study was to investigate the effects of seed culture temperature and fermentation temperature on the production of lactobionic acid from whey by Pseudomonas taetrolens. Hence, the seed culture age, seed culture temperature, fermentation temperature in shake-flask and bioreactor, and two-stage fermentation temperature operation were all discussed in the present study. Finally, illustrate the ideal fermentation mode via the analysis of the product formation kinetics. The results of experiments showed that the optimal seed culture temperature was 35℃, and then the optimal fermentation temperature in shake-flask and bioreactor was 30℃. In this optimal operation, the yield and productivity of lactobionic acid were the highest among other operations, but the highest biomass concentration was obtained from the operation of which fermentation temperature was set at 20℃. Therefore, using the two-stage fermentation temperature operation, the first stage fermentation temperature was set at 20℃ to cause more biomass, and then the second stage fermentation temperature was shifted to 30℃ to enhance the production of lactobionic acid. In this operation in shake-flask, the yield of lactobionic acid was 29.793 g/L, which was about fourteen percent higher than that obtained from the operation of which fermentation temperature was fixed at 30℃. Besides, the productivity of lactobionic acid was 0.198 g/L h, which was about thirteen percent higher than that obtained from the operation of which fermentation temperature was fixed at 30℃. The results of fermentation temperature experiment conducted in bioreactor showed that the two-stage fermentation temperature operation shortened the fermentation time and the productivity of lactobionic acid was about twenty percent higher than that obtained from the operation of which fermentation temperature was fixed at 30℃. According to the analysis of the product formation kinetics, if the product formation is mixed-growth associated type, there will be a better fermentation performance. As a result, adjusting the seed culture temperature or fermentation temperature can make the product formation approaching the ideal type of the product formation kinetics model, thereby improving and enhancing the fermentation performance.
Yang, Cheng-Lun, et 楊政倫. « none ». Thesis, 2017. http://ndltd.ncl.edu.tw/handle/39464116193414864781.
Texte intégral國立中央大學
機械工程學系
105
Industry for efficiency, accuracy requirements are increasing. For the high-speed operation mechanism, the development of magnetic bearing become an irreplaceable trend. Compared with traditional bearing, the friction between the rotor and the bearing is almost zero, won’t cause energy loss and temperature increase, not only greatly improve the life of the machine, and for the speed limit is higher than the traditional bearing. The vibration caused by the unbalance of the rotor is the main excitation source of the high speed operation of the magnetic bearing. Through the automatic balance method of the rotor system of the magnetic bearing based on the unbalance identification, it has a significant inhibitory effect on the unbalanced interference. The method doesn’t need the transfer function of the object and doesn’t affect the stability of the control system. The Fourier coefficient of the unbalanced jamming signal is identified by applying the test excitation signal to the magnetic bearing on-line and detecting the amplitude and phase change of the control current response. To produce accurate compensation signal, improving the operation of stability and efficiency.
Lin, Yen-Yu, et 林彥瑜. « none ». Thesis, 2017. http://ndltd.ncl.edu.tw/handle/04755968798849705484.
Texte intégral國立中央大學
光電科學與工程學系
105
This thesis presents three designs, including 3X, 6X, 9X periscope type zoom lens for eight mega pixels mobile phone cameras. A Periscope type lens system namely put a right angle prism in front of the lens system, which makes optical axis tilt 90 dgrees. If the thickenss of the prism and the aperture of lens in periscope type zoom lens are both smaller than the mechanism thinkenss of a mobile phone, periscope type zoom lens will be able to set inside a mobile phone. The preliminary specifications of 3X zoom lens design are as follows: a focal length range of 4.34 mm to 13.03 mm, a half field of view range of 28o to 10o, a F/# range of 2.8 to 7.5, 6.15 mm in thickness and 32.21 mm in total length. The preliminary specifications of 6X zoom lens design are as follows: a focal length range of 4.34 mm to 26.03 mm, a half field of view range of 28o to 5o, a F/# range of 3.5 to 7.5, 8 mm in thickness and 50.95 mm in total length. The preliminary specifications of 9X zoom lens design are as follows: a focal length range of 4.34 mm to 39.05 mm, a half field of view range of 28o to 3.4o, a F/# range of 3.5 to 7.5, 10 mm in thickness and 61.58 mm in total length. This thesis also analyzes the influence in the thickness of prism, the aperture of lens, the thickenss of whole system for 3X, 6X, 9X periscope type zoom lens respectively when the size ratio of sessor in 4:3 is replaced by 16:9.
SYU, YING-SHUN, et 徐英舜. « NONE ». Thesis, 2017. http://ndltd.ncl.edu.tw/handle/08096351800940974075.
Texte intégral國立中央大學
光電科學與工程學系
105
This paper proposed a ultra-wide lens design, which has 5 Mega pixel, and compose of seven glass, the focal length of the lens is 1.649 mm, the total length is 23.235 mm, F/# is 2.1, the maximum of half field-of-view is 80 degree. In the lens optimization we maintain the system's focal length of the same conditions, While eliminating the design of chromatic aberration and athermal dissipation. Consider the wide-angle lens in the large viewing area of the image will be severely compressed features, The traditional optical distortion assessment method was changed to F-theta distortion as a view of the degree of imaging distortion of the optical system. And consider the use of the ambient temperature range of the car,and the control of the large field angle relative to the illumination. Different lens materials have different coefficients of thermal expansion, at room temperature(T0) conditions, such as the parameters of the lens radius of curvature(R), thickness(D), and aspheric coefficient (a4、a6、a8), when the ambient temperature changes, due to the thermal expansion coefficient of the lens material and temperature changes(T=T-T0), and change the lens parameters. Therefore, in the optical system in the athermal conditions, Therefore, in the optical system in the athermal conditions,the temperature coefficient of the glass material selected by the optical system and the coefficient of thermal expansion of the lens can be used to estimate the diopter change due to the temperature change. And when the dioptric change of the optical system is not zero, you can use the lens barrel material thermal expansion coefficient(β) or change the lens material to achieve athermal. At room temperature(20C),the single temperature of the lens optimization design, you can get the lens at a spatial frequency of 180 lp / mm MTF at least greater than 0.57,but the lens MTF in the range of -30°C to 70°C is reduced to at least 0.423 ,while the lens MTF has the lowest position at room temperature of 70°C. Finally, for the temperature range of -30 ° C to 70 ° C lens optimization design, we consider the glass material thermal expansion coefficient, barrel thermal expansion coefficient, and 7 lens material, for the realization of athermalized can get very good results. The final design for the seven glass lenses, which contains two aspherical lenses, lens imaging quality MTF (180 lp / mm) is at least greater than 0.597 in the temperature range of -30°C to 70°C, MTF changes in the range of 0.597 to 0.627. The relative illuminance is at least greater than 89.89%,and the change in relative illuminance is in the range of 89.75% to 90.53%. Lateral chromatic aberration is at least less than 0.851 m, and the change in lateral chromatic aberration is in the range of 0.851 m to 0.543 m. F-theta distortion is at least less than 0.9%, and the change in F-theta distortion is in the range of 0.9% to 0.83%.
Zeng, Yi-De, et 曾議德. « none ». Thesis, 2017. http://ndltd.ncl.edu.tw/handle/68770144984578224462.
Texte intégral國立中央大學
土木工程學系
105
Taiwan is located at the junction of the Eurasian plate and the Philippine Sea plate. Engineering design often takes into account the effects of earthquakes. In recent years, such as Taiwan Chi-Chi earthquake, China Wenchuan earthquake, Japan Fukushima earthquake and other active faults caused serious damage to life and property. In order to explore the effect of fault on the surface and underground structure, physical tests were usually carried out by Centrifuges in the past. However, physical test is time-consuming and expensive. Therefore, many studies consider the use of Finite Element Method (FEM) and Discrete Element Method (DEM) to simulate in recent year. However, when the fault deformation is too large, the FEM will have a greater error, so in order to get results that are more accurate, this study used DEM for reverse fault simulation. This study referred to the numerical model of sandbox test from Chang (2013). A sandbox test with a maximum vertical displacement of 5cm was simulated at 80g by using PFC2D (Particle Flow Code in Two Dimensions). In order to understand the stress changes in different locations, The model in accordance with the depth into shallow, medium and deep, and then in accordance with the horizontal position into the hanging wall, the transition zone, the footing wall. Then, set the measurement circle by the above principle. The simulation result show that the lateral force of the fault, the boundary effect and the development of the shear zone mainly affected the stress state. Lateral force and the boundary is the most important factor in controlling the principal stress direction. The shear zone mainly affect the transition zone. In order to further understand the relationship between the microstructure and the stress state during fault offsetting, in the analysis of pore change and volumetric strain, it could be found that the state of particle arrangement changed, when the shear zone occurred, stress state became quite complicated. Finally, we discuss the destructive behavior in fault simulation through the shear strain analysis, and hope to know more about the potential threat of fault.
Hsieh, Jheng-Yu, et 謝政育. « none ». Thesis, 2017. http://ndltd.ncl.edu.tw/handle/11653381861746326312.
Texte intégral國立中央大學
土木工程學系
105
Taiwan is an island where located at the Circum-Pacific Seismic Zone. In addition, the Philippine Sea Plate is pushed underneath the Eurasian Plate due to special geographical location. These may be attributed to the main reasons that have formed Taiwan as a mountainous country with complicated geological conditions. Moreover, the torrential rainfall accompanying typhoons frequently causes slope failures such as landslides and debris flows. The landslide of the dip slopes mainly occurs at the sedimentary rock layer of mountains and hills as observed at the west of Taiwan. Dip slopes of sedimentary rock are strongly affected by landslides due to natural disasters including torrential rainfall and earthquake. Moreover, some sedimentary rocks are alternated by different lithologies which contain sandstone and shale. Therefore water cannot infiltrate through the shale layer. As a result, the pore water pressure will increase and lead to the decrease in the shear strength between these layers. Finally, dip slopes will slide along the weaken zone as well as infiltration area. In this study, we discussed the deformation and stress behavior of the dip slopes with two kinds of models. First of all, the bedding plane is parallel to the surface of the plane which will be simulated in the first model. The second model shows that the inclination of slope surface is smaller than bedding plane. In order to further realize the dip slope failure, the landslide of dip slope with different thicknesses of the layers can be observed and estimated by centrifugal modeling test and PFC3D simulation. Basically, the test is performed under the condition of the toe of slope daylight and soaked in water. Moreover, we have to consider the buoyancy at the toe of the slope so that the numerical model can be closer to real conditions. Based on the result of the centrifugal model tests, PFC3D model was first verified through comparing with centrifugal models, and then adopted to simulate and determine the mechanism of dip slope model with different gravity fields. According to the results of the dip slope deformation, the stress paths showed different behaviors at each part of dip slope. In the first kind of model, the stress path showed stre
lee, tse-chen, et 李則辰. « none ». Thesis, 2017. http://ndltd.ncl.edu.tw/handle/51162175137959683488.
Texte intégral國立中央大學
土木工程學系
105
This study is to investigate the surface failure behavior and the underlying soil mechanics mechanism in the vicinity of normal fault. Near the fault can be observed in the vicinity of the fault caused by a large number of soil deformation, but the mechanical changes under the surface can not be seen with the naked eye In this study, PFC2D was used to simulate, because PFC (Particle flow code) was simulated by particle flow, and the mechanical behavior was more close to the experimental sandbox. The measure circle was discussed in the upper and lower sides of the normal fault Mechanical Behavior and Microstructure Variation of Soil Near the Shear Zone in Faults. For the change in porosity during dislocation, it can be seen that most porosity values did not change in the lower panel. For areas near the shear zone, the porosity increases significantly in the upper plate area (shallow soil location). The porosity increases slightly in the bottom area near the shear zone (deeper in the soil). For the change of the stress path and the rotation angle, the stress path is compressed in the lateral direction and then decompressed in the vicinity of the initial value. The change value is within 20 kPa and the rotation angle changes in the positive and negative 5 ° or less, on behalf of away from the shear zone of the stress change is not significant. However, the stress path in the vicinity of the crack zone is axially decompressed after axial compression, especially in the area above the shear zone, and its stress path is more complicated.
Pan, Jun-Wei, et 潘俊瑋. « none ». Thesis, 2017. http://ndltd.ncl.edu.tw/handle/28470887650446961041.
Texte intégral國立中央大學
大氣科學學系
105
In this study, the McGill Algorithm for Precipitation nowcasting using Lagrangian Extrapolation (MAPLE) system developed by McGill University is used to evaluate the very short-term forecast of precipitation in Taiwan. There are two procedures in MAPLE system. First, the motion field of precipitation is determined by Variational Echo Tracking (VET) technique. Second, a radar map is advected by means of a semi-Lagrangian backward advection scheme to be a precipitation forecast. By using composite radar data from Central Weather Bureau (CWB), three real cases are selected for this study: a typhoon event occurred during 30-31 August 2010 (Namtheun typhoon); a Mei-Yu front case occurred during 11-12 June 2012; and a typhoon event occurred during 21-23 July 2014 (Matmo typhoon). Firstly, sensitivity tests between two parameters--vector density of motion field and time difference between each radar map in VET procedure is to determine the best setting of VET parameters for forecast. Secondly, the Quantitative Precipitation Nowcasting (QPN) would be evaluated. In general, forecasts by MAPLE system provide a certain degree capability about values and spatial patterns of the accumulated rainfall except for some rapidly growth and decay regions. Thirdly, the correlation of the VET motion field and the ECMWF reanalysis wind field is examined. It is found that most motion fields have a good relation with wind fields at each level in typhoon events, because the horizontal wind structure at one level is similar to the others. Finally, we focus on those VET motion fields that rainfall echoes are moving into Taiwan. The decrease of motion speed over Taiwan area is a good sign for extrapolation forecast, because it captures the blocking effect by orography to a certain extent. Must pay attention that main reason for rapid decrease in forecast ability is lack of growth and decay mechanism.
Huang, Jyun-Jhe, et 黃俊哲. « none ». Thesis, 2017. http://ndltd.ncl.edu.tw/handle/50233898869887048703.
Texte intégral國立中央大學
化學工程與材料工程學系
105
In the semiconductor industry, low thermal budget is a critical topic. A low thermal budget is achieved by using a polymer substrate, a molecular machine, and 3D integration technology, which are associated with a low glass transition point, low decomposition temperature, and severe warpage, respectively. In conventional assembling technology, low-melting-point solder is an extremely economical solution for a low thermal budget. However, low-melting-point solder used in industry cannot solve the aforementioned problems. According to two eutectic points in an In-Bi phase diagram, solder alloys with the compositions 33In-67Bi wt.% and 68In-32Bi wt.% were selected in this study. Both alloys were reflowed on a Cu substrate 1, 3, 5, and 10 times at a temperature that was 30 oC higher than each melting point. To investigate the intermetallic compounds (IMCs) and phase formation in diffusion couples, samples treated with one reflow cycle were aged at different temperatures. The microstructural evolution and phase formation of two diffusion couples (33In67Bi/Cu and 68In32Bi/Cu) were observed through scanning electron microscopy, X-ray diffraction, electron probe microanalysis, and grazing incidence X-ray diffraction at the National Synchrotron Radiation Research Center. In the 33In67Bi/Cu system, the rate of IMC growth at the interface was quite low. The phase of the IMCs was identified to be Cu2In, and those in the solder were determined to be Bi-rich and InBi phases. The IMC growth rate of the 68In32Bi/Cu system was higher than that of 33In67Bi/Cu. After long-term reflow, IMCs that formed at the interface of 68In32Bi/Cu served as a self-diffusion barrier so that the thickness of the IMCs would not increase. The phases of the IMCs that formed at the interface of the 68In32Bi/Cu diffusion couple were Cu11In9 and CuIn2, and the phases formed in the solder were In-rich and BiIn2 phases. Furthermore, CuIn2 was a metastable phase that could transform to Cu11In9 spontaneously. Consequently, both CuIn2 and Cu11In9 were found at the interface.
Li, Zheng-Xian, et 李政憲. « none ». Thesis, 2016. http://ndltd.ncl.edu.tw/handle/00934537718621638899.
Texte intégral國立中央大學
化學工程與材料工程學系
105
Electrospinning is a scalable process for the preparation of flexible zirconia nanofibrous web useful as a hot gas filter. Composite fibers are formed under polarized electric field from a solution containing zirconium salt and a hydrophilic polymer (PVP) and are later transformed into zirconia via calcination. In this study, the precursor employed was a transparent aqueous sol of zirconia nanocrystals modified with acetate ligand. The surface tension and the conductivity of the precursor were adjusted by the addition of acetic acid and water. The viscosity and the inorganic/organic ratio were adjusted by the concentration of ZA and PVP. Under proper operation conditions, smooth fibrous web without bead structure could be electrospun. The zirconia mat obtained remained flexibility after calcination at 500°C and withstood 400 times of 180° bending. This temperature is lower than that required by literature processes using amorphous precursor. Consequently, the problem of fiber fracture due to crystallization was eliminated. Upon increasing the calcination temperature and duration, the monoclinic phase started to appear which break the fiber and remove its flexibility due to volume expansion. We further prepared flexible mats with nanofibers of different diameters, and study the filtration of NaCl dust. Our mat could achieve more than 99.9% removal with less than 200 Pa pressure drop at 20 LPM flow rate.
Ting-Shu, Yang, et 楊庭菽. « none ». Thesis, 2017. http://ndltd.ncl.edu.tw/handle/27269683286152572938.
Texte intégral國立中央大學
化學學系
105
The photovoltical performance of a P-type conjugated polymer can be tuned by changing the molecular structure and weight. In this study, 8-bis(5-ethylhexyl)thiophen-2-yl)-2,6-di(thiophen-2-yl)benzo[1,2-b:4,5-b'] dithiophene was used as a donor unit and bromo-2,3-bis(4-(hexyloxy) phenyl)pyrido[3,4-b]pyrazine was used as an acceptor to construct the copolymer P11. Furthermore, an electron-withdrawing alkylthio chain was attached on the donor to form P12, or adding electron-withdrawing fluorine atoms on the acceptor to prepare P14. P15 has alkylthio chain on the donor and fluorine on the acceptor. Combining these four new copolymers with P9 and P10 (without thiophenebridge) prepared in our lab before, the properties- photovoltical performance relationship were investigated. The results showed that the conjugation length of P11 and P12 which containing thiophene bridge was longer than P9 and P10, respectively therefore the corresponding solar cells have higher Jsc value. P15 has higher molecular weight, large absorption coefficient, good crystallinity and forms an interpenetrating bicontinuous network when blend with PC61BM. As a result, inverted cell based on P15 copolymer exhibits the highest Jsc value (11.70 mA/cm2), FF value (0.53) and conversion efficiency (4.50%) amongst the copolymers studied in this thesis. In addition, increasing the molecular weight of P2 by using the fresh prepared Pd(PPh3)4 as a catalyst, or by Soxhlet extraction of P15 with high polar solvent. We have proved the copolymers with higher molecular weight have the efficiency (P2:1.67%, P15:4.31%) higher than that of copolymers with lower molecular weight (P2:0.91%, P15:2.43%).