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Achromatic Electro-tunable Linear Polarization Rotator
No full textPolarization, commonly indicates the vibration of the electric field in an EM wave. To category more detail, the polarization can be separated into linear polarization, circular polarization and elliptical polarization depends on the phase difference. Polarization has been applied in various technologies. For example, the common use is to controlling the polarization and modulate the transmittance through polarizers as the gray scale of the displays; in polarization image, the screen is separated into four polarization to compare the concentration of each polarization to enhance the contrast of the image; in optics communication, the different polarization can be used as different channel to enlarge the load of the information. Studies nowadays have approached many methods to control the polarization like the wave-plates based on birefringent materials, faraday rotators and liquid crystal tunable wave-plates. However, the approaches mentioned above always relate to the operating wavelength which results in a severe dispersion during the control of polarization and restrict the application.
Liquid crystal, the best selection to control the light by electric with their birefringence and the dielectric difference properties. The common used liquid crystal technology in displays is the twist nematic liquid crystal (TNLC). With the aligned direction on the substrates, the liquid crystals will behave the continuously rotating. With the stacks of the phase donated by the rotating liquid crystal molecular, the input polarization will be rotated to the twist angle of the TNLC which is determined by the substrates and the linear polarization will be maintained. The operation condition of the polarization rotation of the TNLC can be classified into Gooch Terry (GT) and Mauguin\ue2s condition. With Gooch Terry condition, TNLC has no incident polarization selectivity but very severe dispersion. And TNLC that satisfies the Mauguin\ue2s condition has an achromatic polarization rotation characteristic and limitation of incident polarization dependent. In both GT and Mauguin\ue2s condition, the rotation angle of output polarization is fixed due to the boundary and can not be modulated by the external field, thus the appliance with TNLC is still restricted.
In my study, we approach a combination of the liquid crystals and hybrid alignment to realize the TNLC with different effective twist angle with different strength of the electric field that results in continuously polarization rotation. Besides, during the modulating process, the device will always meet the Mauguin\ue2s condition and the rotation angle will be achromatic. (1) In experiment 1, we demonstrate the achromatic linear polarization rotator from 0\uc2\ub0 to 90\uc2\ub0 with the negative liquid crystal and hybrid alignment, the hybrid alignment consists of a planar and a vertical aligned substrates and the substrates are rubbed with perpendicular directions. With applying external field, the liquid crystal molecular nears vertical boundary will be gradually rotate to 90\uc2\ub0 and form the TNLC with different rotation angle. Thus the input polarization will be continuously rotated from 0\uc2\ub0 to 90\uc2\ub0 with the variation of \uc2\ub12\uc2\ub0. (3) In experiment 2, we use the duelfrequency liquid crystals doped with chiral dopant and hybrid alignment (the substrates are rubbed with the parallel directions) to realize the 0\uc2\ub0 to 180\uc2\ub0 polarization rotation in single component. From the assistance of the chiral dopant, the liquid crystal will arrange from low tilt angle to high tilt angle with rotation in the hybrid aligned substrates, the area with high tilt angle has low birefringence will not contribute the phase stacks which results in that the polarization rotation will be near 90\uc2\ub0 but not 180\uc2\ub0 even the liquid crystal rotates with 180\uc2\ub0. Applying the external field at frequency lower than the critical frequency, the liquid crystal orients with the positive dielectric difference, the area with high tilt angle will increase and effectively decrease the twist angle of the twist nematic liquid crystal. Applying with external field at high frequency over the critical frequency, the area with high tilt angle will be decreased and effective enlarge the twist angle. In this way, the polarization from 102\uc2\ub0 to 0\uc2\ub0 and 102\uc2\ub0 to 180\uc2\ub0 with applying low frequency and high frequency is achieved, respectively. The variation of the rotation angle will be less than \uc2\ub13\uc2\ub0. The polarization rotation from 0\uc2\ub0 to 180\uc2\ub0 can meet most of the technologies that depend on the polarization. Finally, we apply the polarization rotator, hybrid aligned liquid crystal and polarizers with parallel directions to realize functions of onedimensional light field shaping and tinting. Doped with ions into the negative liquid crystals and selection in applied frequency of the AC bias, the device can also perform the scattering state by the electrohydrodynamic effect for the privacy protection. With the transparent state, the transmittance will be 38% and can reach to 2% with a viewing angle of 50\uc2\ub0. With applying external field with high frequency, the tinted state will show up and the transmittance can be lowered to 0.2% with haze value of 3%; Applying external field with low frequency, the scattering state can reach a high haze value of 99%. With these performances, we achieve the multi-function smart glass. The achromatic polarization rotator has a great potential to the applications nowadays, hope this device can be utilized in various optical systems and bring the possibilities to the optics designs
Analysis on Strategies of Taiwanese Banks in Setting Up Overseas Branches and Subsidiaries: A Case Study
No full textTaiwan financial authority has permitted the establishment of new domestic banks in the 1990s. The high competition among banks was followed and squeezed profitability of most banks. Most Taiwan's banks were incentivized to seek growth opportunities abroad and strengthened their strategies to set up overseas branches or subsidiaries.
For those banks, how to effectively evaluate overseas development business is their important concerns and is the focus of this study. This study adopts a case study method and takes the domestic iconic \ue2A Bank\ue2 as the case study object. The study uses relevant literature to analyze A Bank\ue2s strategic considerations for setting up branches / subsidiaries. The theories of Porter five forces and SWOT/TOWS were deployed to analyze A Bank\ue2s decision-making factors of expanding overseas business opportunities. It also explored the methods of differentiated competition to scoop niche markets, and strategies based on A Bank\ue2s strengths and weaknesses. Finally, from the perspective of the bank's long-term development, the study has made suggestions such as business model upgrades
Program Notes of Cyong-Ru Wang Vocal Recital
No full textThis report is the program notes of Cyong-Ru Wang\ue2s Vocal Recital held on November 17, 2023, and required for the master\ue2s degree.
The repertoire includes the aria \ue2Sposa son disprezzata\ue2 from the opera Bajazet by the Italian composer Antonio Vivaldi of the Baroque era, two songs by the composers Domenico Cimarosa and Giovanni Paisiello of the classical era. For the works of Romantic era, there are three songs by Vincenzo Bellini, four German Lieder by Robert Schumann, four French melodies by Reynaldo Hahn and Hector Berlioz. The repertoire also includes the aria \ue2Mon c\uc5ur s'ouvre \uc3\ua0 ta voix\ue2 from the opera Samson et Dalila and the vocal chamber music titled Three Songs by Frank Bridge of the twentieth century.
This report consists of program notes and singing interpretation on the works, including their background knowledge, original and translated texts as well as insights from a singer\ue2s point view
Sustainable water resource management: Disinfection byproducts formation during chlor(am)ination of benzylamines and an application of a graphene oxide composite membrane for treatment of benzylamines and disinfection byproducts formation in water
No full textThis study endeavors to achieve sustainable management of water resources by investigating multiscale issues from diverse perspectives. The discussion begins with global risk management trends, focusing on pollutants and their harmful disinfectant byproducts. By proposing a treatment using GO composite membranes, the study assesses their effectiveness in precursor removal and byproduct inhibition.
Chapter 2 applies scientometrics to Google and Web of Science, identifying and categorizing keywords into technological, organizational, and environmental groups. Public concerns are highlighted by \ue2water conservation\ue2 and \ue2water crisis.\ue2 Academic concerns reveal significant risk factors, including \ue2statistical analysis\ue2 (10.7%), \ue2climate change\ue2 (8.15%), and \ue2uncertainty\ue2 (6.52%). \ue2Pollution\ue2 (3.81%) ranks eighth, connecting to \ue2wastewater\ue2 and \ue2regulation,\ue2 underscoring its significance.
Chapter 3 explores the mechanisms of disinfection byproducts (DBPs) from benzylamines (BAs) with varying methyl groups. The results reveal that BAs react with chlor(am)ine to form nitrosamines. The critical mechanisms are dictated by the number of methyl groups and the type of disinfectant. Dimethylbenzylamine shows a high formation potential (52.4%) of N-nitrosodimethylamine (NDMA) during chloramination, underscoring the need for effective treatment to remove this precursor.
Chapter 4 introduces the development of a graphene oxide-iron (GO-Fe) composite membrane using divalent iron ions. The results indicate that the GO-Fe composite membrane maintains GO characteristics, enhancing stability by crosslinking oxygen-containing functional groups within the layers. Filtration with acidic, alkaline, and oxidative solutions impacts membrane properties, reducing water flux (~10 Lm\ue22h\ue21bar\ue21) and altering surface characteristics. Specifically, acidic solutions lead to iron ion precipitation (1.60 mg/L), disrupting membrane structure and efficacy.
Chapter 5 evaluates the efficacy of the GO-Fe composite membrane against pollutants such as BAs and pharmaceuticals, considering chlorine resistance, water flux, and removal efficiency. The results demonstrate an improved removal rate (17.3% to 25.7%) upon contact with chlorine. Despite achieving only a 20-40% removal rate of precursors, the formation potentials of DBPs were reduced (p<0.05) after filtration. This reduction could be attributed to the interaction among chemicals.
Overall, this thesis intends to address sustainable water resource issues. It begins with global-scale risk management and gradually narrows the focus to examine the formation of carcinogenic DBPs from BAs. The development and application of the GO-Fe composite membrane to assess the practicality of addressing these emerging pollutants and their associated DBPs were investigated
A Six Switches Inverter with Common-Ground and Buck-Boost Capability
No full textAs the demand for renewable energy sources like solar power grows, the need for advanced and adaptable power conversion solutions becomes paramount. Through photovoltaic (PV) system the voltage produced is significantly impacted by environmental variables such as irradiance level, partial shading, and temperature. To regulate (AC) output voltage across an input voltage which has wide range, the PV power conditioning system plays a crucial role. This thesis presents the proposed inverter which has a space-saving design and has buck-boost capability. Its design can be accomplished by a capacitor and adding input and output LC filters with incorporated six switches. The proposed inverter establishes a common ground reference point between the PV panel and grid, effectively eliminating the variations in common-mode voltage. Thus, the common mode voltage is constant, the flow of leakage current is eliminated. In laboratory experiments are carried out on a hardware prototype to affirm the practicality of proposed inverter. The prototype under consideration operates at the specified power of 300W. It's designed to meet an output voltage requirement of 110Vrms. To simulate grid voltage disruptions, a single-phase power supply is utilized, ranging from 100V to 200V
Silicon photonics multi-function integrated optical circuit for interferometric fiber optic gyroscope
No full textThe objective of this study is to integrate the discrete optical components of a conventional fiber optic gyroscope into a silicon photonic integrated platform provided by IMEC foundry to reduce the assembly cost and system power consumption, with a view to enhancing the performance of the gyroscope for miniaturized applications. Due to the high refractive index difference of the silicon waveguide (\uefn = 2.03), the chip area can be significantly reduced to 4 x 1.2 mm2, which is much smaller than the conventional LiNbO3 chip. Our system utilizes a grating coupler array as the optical I/Os of the silicon chip, which not only exhibits good filtering and polarization characteristics but also offers excellent space utilization in the layout design, as well as good tolerance and reliability in the alignment of the fiber array package. Besides, the sinusoidal polarization beam splitter and the grating couplers can increase the polarization extinction ratio to over 60 dB. The package prototype is reinforced with UV light dispensing technology and an external metal enclosure. By optimizing the asymmetric square wave modulation technique, the non-reciprocal bias signal is successfully suppressed. The linearity error less than 500 ppm is observed in all rotation rates except for the lowest rate (\uc2\ub1 1 o/s), as determined by Fourier series fitting. The angle random walk and bias instability obtained by Allan deviation are 0.097 \uc2\ub0/\ue2hr and 0.105 \uc2\ub0/hr, respectively, meeting the specifications for tactical applications. Furthermore, we have demonstrated the use of the gyro chip for orientation determination by measuring the Earth\ue2s rotation rate, which is a significant milestone in developing a low-cost and compact inertial measurement unit
The influence of the moral leadership on the intention to stay: The mediating effect of job engagement and the moderating effect of employee assistance programs
No full textEmployee turnover has consistently been a concern for companies, particularly with the younger generation where the turnover rate is relatively high. This may be attributed to corporate culture or leadership styles that are not favored by young individuals, leading to a decline in their intention to stay. This is the focal issue of the current study.
Therefore, the main purpose of this study is to understand whether moral leadership influences the intention to stay and to investigate whether job engagement acts as a mediator in the relationship between moral leadership and the intention to stay. Furthermore, the study aims to examine whether employee assistance programs moderate the relationship between job engagement and intention to stay.
This study conducted a quantitative questionnaire survey for data collection, with a total of 293 valid responses. Through statistical methods such as descriptive statistics, correlation analysis, confirmatory factor analysis, multiple regression analysis, and bootstrapping, the results of testing the research hypotheses are as follows:
1.Moral leadership significantly and positively influences the intention to stay.
2.Moral leadership significantly and positively affects job engagement.
3.Job engagement significantly and positively influences the intention to stay.
4.Job engagement mediates the relationship between moral leadership and the intention to stay.
5.Employee assistance programs do not moderate the relationship between job engagement and the intention to stay.
Based on the above research findings, there are concrete research results and recommendations available for reference in practical business management, along with suggestions for future research
The impact of Cast on movie theater attendance: A case study of Taipei\ue2s Movie Theaters
No full textThis thesis discusses the impact of cast on the number of movie attendance in the film industry. The purpose of the thesis is hoped that under the high-risk production of the film industry, controllable factors can be provided for the reference of the production team. Movie attendance data and film information were collected from the movie box office database and IMDb database, covering the period from 2017 to 2022. The dataset includes 4,247 movies, with 650,000 observations. The impact of the cast on the number of people entering the movie theater is explored using OLS Multiple Regression Analysis.
Referring to Basuroy and Ravid's (2003) research, the author considers Oscar awards received by actors as "cast" indicators. For this thesis, modifications are made to align with the Taiwan market, incorporating influential American, Taiwanese, and French film festivals such as the Oscars, Golden Horse Awards, Taipei Film Festival, and Cannes Film Festival.
The research findings highlight that audiences are indeed more inclined to pay for movies featuring notable casts. Consequently, the inference drawn for the Taiwan market is that, given the cast indicators are established based on actor awards from ceremonies, it signifies a certain degree of the actor's popularity in the market. Audiences may perceive these actors as a guarantee of film quality, making them more likely to opt for such movies. Additionally, the level of cast indicators may influence the film's marketing and promotional strategy, and the inclusion of award-winning actors provides the film with additional promotional resources.
From a production standpoint, the recruitment of actors with a certain level of ability, particularly those recognized by the Oscars ceremony, introduces a controllable element that resonates with the audience.
The managerial implication of this study is to provide controllable factors, and casting emerges as a key controllable aspect in film production. Therefore, building on the findings of this study, selecting actors who have a record in film festivals or award ceremonies when making films may offer a better understanding of film performance. This, in turn, could contribute to the ongoing development of Taiwan's film market
Research on the Relationship among Hierarchical Career Plateau, Silence Behavior and Intention To Leave: The Moderating Effects of Interactional Justice and Internal Locus of Control Personality
No full textDuring the global pandemic, t he business leaders reflected on their strategies. Enterprises with innovation and adaptability effectively seized opportunities, prompting leaders to focus on capabilities needed for rapid changes. Employees willingly share crucial observations within the organization, fostering development and innovation. This readiness helps navigate changes in unknown environments. Conversely, Employee silence often signals perceived stagnation in organizational development. This study examines the Hierarchical Career Plateau perceived by employees, which often leads to Intent to Leave. Could the Silence Behavior be another organizational behavior manifestation? This study explores the impact of Interactional Justice and Internal locus of control on Employee Silence and aims to offer strategies for businesses to encourage active employee expression, fostering continuous improvement, innovation, and adaptability to unknown environmental changes.
This study utilized an online survey to investigate employed individuals in Taiwan with a minimum of three years of work experience. The survey was conducted in two phases and yielded 395 valid responses. The results reveal that Silence Behavior acts as a mediator between Hierarchical Career Plateau and Intention To Leave. The result of moderating effects, the perception of Interactional Justice influenced by the Internal Locus of Control Personality significantly impact the relationship between Hierarchical Career Plateau and Silence Behavior. Additionally, Interaction Justice and the Internal Locus of Control Personality trait couldn\ue2t exert independent effects on the Hierarchical Career Plateau and Silence Behavior relationship
Seamless Handover and Privacy-Preserving Network Slice Selection for Enhanced Authentication in Beyond 5G
No full textThe speed of 5G is as different from 4G as a rocket is from a car. The potential of 5G has been widely publicized, especially in the context of enabling emerging technologies, such as the Internet of Things (IoT), autonomous vehicles, and virtual reality. The ITU-R defines three major areas of enhanced 5G functionality: Enhanced Mobile Broadband (eMBB), Ultra-Reliable and Low-Latency Communications (uRLLC), and Massive Machine-Type Interconnection (mMTC). These areas aim to realize high-speed, high-capacity transmission, very low latency and high reliability, while supporting a large number of IoT devices. Against this backdrop, network slicing has become the central focus of 5G.
As a crucial feature of 5G, network slicing enables real-time monitoring and dynamic allocation of physical resources to handle large amounts of network service demand in a fair and efficient manner. However, this innovation also brings new challenges, especially in security and privacy. The privacy of network slicing has been protected by several scholars. Despite these shortcomings, existing security and privacy solutions for service-oriented network slicing still have some shortcomings. A key component of 5G networks is the handover mechanism. To ensure continuity and quality of communications, 5G networks require a fast and secure handover mechanism.
Therefore, this research focuses on designing a handover mechanism that combines user privacy protection and network slicing security features. It includes various aspects such as authentication and handover to ensure 5G reliability and performance. These efforts will help realize 5G's full potential and drive the proliferation of emerging services and applications. Compared to existing related efforts, our protocols provide more efficient transmission, but also reduce computational costs. Through these measures, 5G reliability and performance will be further enhanced