In recent years, LEV and hybrid has been gradually popularized due to the energy crisis and increasing environmental awareness. The prevalence of LEV is to use batteries to replace the power from the gasoline. Secondary lithium battery is a good option for LEV since it has the features of light weights, high power density, long life, low pollution, and works without memory effect. However, the safety is a concern for end-users with more and more recalls of lithium-ion batteries involving the explosions. The purpose of this research is to propose a systematic approach of battery safety device with an engineering design method. The analysis on the factors affecting the safety is prior to the objective of this study as to define the specification of the battery safety device. Then, substance-field analysis and standard is to improve the initial systematic model, and the solution is specified with the synthesis of morphological matrix. Under the safety test for batteries, the effectiveness and feasibility of protected device is eventually verified.

<p>High tunability and low loss tangent of ferroelectric thinfilms offer unique opportunity for the development of variousmicrowave devices. Silver tantalate niobate, which showsexcellent microwave properties, was selected for this study.Ag(Ta,Nb)O₃(ATN) showed week dielectric dispersion in a widefrequency range from 1 kHz up to 100 GHz, negligible losses upto 30 GHz, and ease to tailor paraelectric state in a widetemperature range by Ta:Nb ratio.</p><p>This thesis is mainly based on the synthesis andcharacterization of niobate ferroelectric ATN thin films. Thinfilms for various measurements were prepared by pulsed laserdeposition and rf-magnetron sputtering techniques.</p><p>X-ray diffraction (XRD) pattern show that ATN/Pt₈₀Ir₂₀films have been found to be (001) preferentiallyoriented, while the epitaxial quality of ATN/LaAlO₃heterostructures have been ascertained. Dielectricproperties were analyzed by measuring the relationship betweendielectric permittivity and frequency as well as dielectricpermittivity and temperature. Reliable tracing of theferroelectric hysteresis polarization versus electric loopsindicate the ferroelectric state in ATN films at temperaturebelow 125 K and yields the remanant polarization of 0.4µC/cm²@ 77 K.</p><p>The fundamental current-voltage behavior in Ag(Ta,Nb)O₃ferroelectric films was measured usingMe/Ag(Ta,Nb)O₃/Pt₈₀Ir₂₀, Me = Pd, Au, Cr, and Al, vertical capacitivecell structures with different top electrodes. Various kinds ofconduction mechanisms such as Schottky emission, Poole-Frenkel,Fowler-Nordheim, and ionic conduction were classified.</p><p>Finally, by fabricating interdigital capacitors on the oxidesubstrates, the characteristics and performances of Ag(Ta,Nb)O₃varactors were examined. Au/Cr/ATN/LaAlO₃interdigital capacitors exhibited loss tangent aslow as 0.0033 @ 1 MHz, weak frequency dispersion of 5.8 % in 1kHz to 1 MHz range, tunability as high as 16.4 %,<i>K</i>-factor (tunability/tanδ) higher than 48.</p>

A multi-channel wireless implantable neural recording (WINeR) system for electrophysiology and behavioral neuroscience research applications was proposed. The system is composed of two units: a system-on-a-chip (SoC) transmitter (Tx) unit and a receiver (Rx) unit. In the Tx unit, the outputs are combined with marker signals and modulated into pulse widths after the neural signals are amplified and filtered by an array of low-noise amplifiers (LNA). The next step involves time-division multiplexing (TDM) of pulse-width modulation (PWM) signals. The TDM-PWM signal drives RF transmitter block and is transmitted by an antenna. To satisfy the needs of neuroscientists during animal experiments, the proposed WINeR system provides long-term recording with inductive powering and stimulus-artifact rejection for closed-loop operations, which requires simultaneous stimulation and recording. The Rx is another critical unit for wireless-link communication. To increase the area of wireless coverage, multiple antennas are used for the Rx. In addition, the automatic frequency-tracking method is used to track free-running Tx frequencies, and a smart time-to-digital conversion method is used to reduce noise and interference. A high-throughput computer interface and software are also developed to continuously receive and store neural data. The WINeR system is a potential tool for neuroscientists due to several advantages, such as a reliable wireless link with large coverage and no blind spots, low power consumption, an unlimited power source, and a stimulation function.

Hand held device users encounter various forms of distraction in their daily lives. Distractions may prevent them from correctly using the hand held device. Usability evaluations are meant to identify issues prior to end-users experiencing them. However the laboratory environment, which usability evaluations are conducted, may not reflect the real-world conditions that devices are used. The experiment involved each participant performing tasks in both a quiet and a noisy environment. The noisy environment emulated part of a real-world experience by adding social noise in the background during the participant's tasks. The goal was to compare how much insight each participant was able to achieve from the data in each of the environments. It was found that task performance accuracy was higher in a quiet environment as opposed to the noisy environment. The mental demands and frustration of participants were found to be higher during the noisy environment evaluation.

Nanoclusters have special importance in nanotechnology because of their low dimensionality, which provides electronic, chemical, and magnetic properties that differ from those of the equivalent bulk materials. Suitably controllable self-assembly methods are required in order to incorporate nanoclusters into useful devices. The self-assembly method used in this study employs V-grooves as a template element for nanocluster device fabrication. The V-grooves are fabricated by optical lithography on SiO2/Si wafers and KOH wet etching. Bi clusters deposited on a V-groove form a self-assembled conducting wire. The clusters are produced using an inert gas aggregation source inside an ultra high vacuum compatible system. In order to characterise the assembly process, Bi clusters with different average sizes and velocities are deposited on V-grooves with different widths. The cluster bouncing was found to be the main process in forming the cluster wires. The bouncing angles were smaller than the incident angle, and they are dependent on the cluster size and velocity. For a certain bouncing angle, the wire width reflects the V-groove width because of the fixed bouncing angle. Nanocluster devices were fabricated by depositing the clusters on V-grooves with pre-formed Au/NiCr electrical contacts. The amount of the deposited material required to form an electrically conducting wire was found to be a function of the V-groove width and the wire length. The two point I(V) measurements in the voltage range between -1 and +1V showed linear characteristics for low resistance wires (kΩ), and non-linear characteristics for the high resistance ones (MΩ). The silicon substrate was used as a back gate. Applying a voltage to the gate was found to modify the electrical conduction of the cluster wire. The temperature dependence of the resistance of the nanocluster wires was studied in the temperature range of 4.2-473K, and all of the measured wires showed a negative temperature coefficient of resistance. These measurements allowed a detailed study of the conduction mechanisms through the cluster wires. The study showed that Bi clusters can be used for device fabrication. To size select the clusters prior to using them for the device fabrication, a high transmission mass filter is required. This transmission can be obtained using the von Issendorff and Palmer mass filter if it is operated using the optimum operation conditions. The mass filter consists of two pairs of parallel plates with horizontal openings in Plates 1 and 2, and it operates on the time of flight principle. During this project, the operation conditions of this mass filter were studied using both experiment and simulation. The study showed that the beam deflection angle is a critical factor in optimising the mass filter transmission efficiency. This angle is dependent on the accelerating voltage, ion mass, and the horizontal velocity of the ions. The optimum operation conditions for the mass filter were found and used to study the mass distribution of Pd ions produced by a magnetron sputtering source with variable cluster aggregation length.

ACPEL devices were fabricated onto various paper substrates. The dielectric and phosphor layers were mask printed, a PEDOT:PSS/SWCNT ink was inkjet-printed for the cathode and a translucent conductor was applied with a paintbrush for the anode resulting in a maximum luminance of 8.05 cd/m2 at 300 VAC and 60 Hz. It was found that the conductivity of the PEDOT:PSS/SWCNT ink on the various paper types was affected by the coating and paper thickness. Novel ACPEL devices were also fabricated by incorporating paper as the dielectric layer of the device. The maximum luminance achieved was 7.24 cd/m2 at 300 VAC and 60 Hz. It is shown that the dielectric constant of the paper and hence the performance of the resulting EL device may be enhanced by filling the sheet with BaTiO3 and by the surface treatment of the sheet.

ACPEL devices were fabricated onto various paper substrates. The dielectric and phosphor layers were mask printed, a PEDOT:PSS/SWCNT ink was inkjet-printed for the cathode and a translucent conductor was applied with a paintbrush for the anode resulting in a maximum luminance of 8.05 cd/m2 at 300 VAC and 60 Hz. It was found that the conductivity of the PEDOT:PSS/SWCNT ink on the various paper types was affected by the coating and paper thickness. Novel ACPEL devices were also fabricated by incorporating paper as the dielectric layer of the device. The maximum luminance achieved was 7.24 cd/m2 at 300 VAC and 60 Hz. It is shown that the dielectric constant of the paper and hence the performance of the resulting EL device may be enhanced by filling the sheet with BaTiO3 and by the surface treatment of the sheet.

Most companies and organizations today depend on technology connected to the Internet. Schools and offices have therefore been providing computers, phones and other technology to the employees. The recent technological development and decline in prices for technology have contributed to making these products a part of everyday life for most people. This has made it very common for employees and students to bring their own devices into school and workplaces. The aim of this study is to define what "Bring your own device" means for Swedish companies and organizations and how it has been implemented in those. The aim is not mainly to generalize to all Swedish companies but create an understanding how the trend is used to provide a basis for continued research in this area. The questions this thesis aims to answer is: What does the term "Bring your own device" mean in the Swedish organizations and companies in which it is implemented? How is "Bring your own device" implemented in Swedish organizations and companies? What are the policies and guidelines for the Swedish organizations and companies that have implemented "Bring your own device", and how is compliance? A pragmatic approach has been used to incorporate previous studies while keeping the interview questions open to new approaches. The structure has been small-N studies that go deep into a number of cases, in order to more profoundly explain a phenomenon. Mail interviews have been used to collect data from the persons responsible for "Bring your own device" in the different organisations. The result shows that companies see "Bring your own device" as a trend where employees bring their own devices rather than firms providing employees with devices that they use privately. Respondents have not measured or examined how the introduction of BYOD has affected productivity. It seems, like in foreign studies, to be a lack of clear policies and guidelines regarding the phenomenon. / De flesta företag och organisationer är idag beroende av teknologi kopplad till Internet. I skolor och kontorslandskap har man därför sett till att förse de behoven som har funnits när det gäller datorer, telefoner och annan teknologi. De senaste årens tekniska utveckling och prisnedgång på teknologi har medverkat till att användningen av dessa produkter har blivit en del av vardagen. Detta har medfört att det har blivit allt vanligare att ta med sina egna enheter till skolor och arbetsplatser. Syftet är att definiera vad ”Bring your own device” (BYOD) innebär för svenska företag och organisationer och hur det har implementerats hos dessa. Främst är inte syftet att generalisera till alla svenska företag utan förstå hur trenden är implementerad för att ge en grund åt fortsatt forskning inom området. Frågeställningarna har varit följande: Vad innebär begreppet ”Bring your own device” i de svenska organisation-er och företag där det är implementerat? Hur är ”Bring your own device” implementerat i svenska organisationer och företag? Hur ser policys och riktlinjer ut i de svenska organisationer och företag som har implementerat ”Bring your own device”, och hur efterlevs dessa? En pragmatisk ansats har använts för att kunna dra fördel av tidigare studier samtidigt som intervjufrågorna har varit öppna för nya infallsvinklar. Upplägget har varit enligt små-N-studier där man går djupt in på ett antal fall, detta för att på ett mer grundläggande plan kunna förklara ett fenomen. För att samla in empiriska data har mailintervjuer gjorts av den ansvariga personen för ”Bring your own device” i respektive organisation. Resultatet visar att företag ser ”Bring your own device” som en trend där anställda tar med sig egna enheter snarare än att företagen förser anställda med enheter som de använder privat. De tillfrågade har inte mätt eller undersökt hur införandet har påverkat produktiviteten. Svenska företag och organisationer verkar agera på ungefär samma sätt som framkommit i utländska studier där tydliga policys och riktlinjer hos företag och organisationer kring begreppet BYOD saknas.

This study investigated the impact of Bliss based computer augmented communication (CAC) on the daily communication and daily activities of severely disabled speech impaired children from a Finnish school for disabled children from the point of view of the children, their discussion partners and therapists; it also investigated the value and meaning of the CAC devices for them. The school staff had considerable experience in the use of computers with disabled children, but only a few had any experience of CAC. In order to gain a rich understanding of the subject matter, a qualitative multiple case study approach was adopted. The longitudinal study investigated CAC in the real life environments of six severely disabled speech impaired children, aged 7 to 15 years, their parents, helpers, teachers, speech therapists and occupational therapists. All of the speech impaired children had cerebral palsy and their main mode of communication was Blissymbolics, used with the aid of a communication folder. The multiple methods of data collection used in the study included interviews, videotaped observations, the Assessment of Communication Skills Questionnaire, essays and data logs. The data gathering started before the participants received their CAC devices and continued 3,6 and 12 months after they received the devices: it involved studying participants in three different communicative environments. The data analysis was conducted by a narrative analysis of each individual case, which was followed up with a cross-case analysis. The process of CAC was highly individual and context dependent. During the study all the speech impaired participants learned to operate their CAC devices. Their initial enthusiasm begant o decreaseth ree to six months after the participants received their devices.A t the end of the study year, one of the participants used his CAC device nearly daily in two of his communicative environments, two of them used their devices regularly a couple of times a week, two of them hardly at all, and one not at all. The CAC devices were hardly used for face-to-face communication, they were mainly used for educational purposes, written communication, play and leisure. The children and their discussion partners perceived that the main reasons for not using CAC devices were the poor usability of devices, such as slow speed of CAC and insufficient vocabularies, and insufficient related services. During the CAC process the motivation to communicate of four participants increased, the communication folder use of three participants increased and vocalisations of two participants increased. V Despite of the perceived limitations of CAC, the speech impaired children considered the CAC devices important for them and helpful primarily in school work and play. Participants' discussion partners assessed that CAC enriched the children's communication and increased dialogue between themselves and the children. Discussion partners also considered as particularly important the participants' independence in being able to operate the CAC devices themselves and their possibility to use voice output. New opportunities provided by CAC devices were especially meaningful to the participants' parents. The study showed that CAC requires substantial highly specialised services and a number of recommendations were made on the basis of the study. CAC interventions should focus on not only the operative and communication skills of the users. Professionals conducting CAC interventions should evaluate more carefully what users need and subsequently evaluate whether the CAC devices meet these needs. They should also understand and support the motivational processes and psychosocial aspects of developing the use of CAC. The findings suggest that CAC devices should be introduced to severely disabled speech impaired children as an additional mode of communication for face-to-face and indirect communicative purposes and within the context of meaningful activities. This study has shown that CAC is an extremely complex phenomenon with a mixture of interrelated elements that affect the daily communication and daily activities of severely disabled speech impaired children.

This thesis consists of a study of several thin film semiconductor structures of practical technological use either presently or in the near future. The first system studied is an ultra thin film single crystal gallium arsenide layer. The absorption spectra of these layers are measured and transitions at both the F- point and L-point of the Brillouin Zone are observed, the latter are not normally measurable in thicker layers. The observed shift in the F-point absorption edge is attributed to contributions from the Franz-Keldysh Effect and the Moss-Burstein Effect. The temperature dependence of the L-point energy gap is measured and compared with previous data. The next system investigated is an n-type porous silicon layer coated with p-type polyaniline. Both photoluminescence and electroluminescence spectra and the electrical characteristics have been measured for this system. The interface between the two layers is found to be a rectifying junction consistent with a potential barrier formed at the interface. In forward bias, it is possible to generate electroluminescence in the visible and near infra red regions. The final structure studied is a thin film cadmium sulphide-cadmium telluride solar cell structure. The cells are found to have a low efficiency of around 1% as grown, but a process of treatment with cadmium chloride and annealing in air improves this by a factor of approximately ten. Photoluminescence measurements on the back surface of the cadmium telluride revealed three major emission bands at 1.59 eV, 1.55 eV and 1.45 eV. By varying temperature and incident laser power, attempts at assigning the bands to specific impurity centres in the cadmium telluride is made Using a novel bevelling etch technique to prepare samples, depth dependent measurement of the photoluminescence is possible. This reveals that the major changes associated with the improvement in efficiencies occurs at the interface between the CdS and the CdTe.