"Recommender systems are being widely applied in many E-commerce sites to suggest products, services, and information items to potential users. Collabora-tive filtering systems, the most successful recommender system technology to date, help people make choices based on the opinions of other people. While collaborative filtering systems have been a substantial success, there are sev-eral problems that researchers and commercial applications have identified: the early rater problem, the sparsity problem, and the large scale problem. Moreover, existing collaborative filtering systems do not consider data re-cency. For this reason, if a user's preferences have changed over time, the sys-tems might not recognize it quickly. This thesis studies how to apply data re-cency to collaborative filtering systems to get more predictive accuracy. We define the data recency problem as the negative impact of old data on the pre-dictive accuracy of collaborative filtering systems. In order to mitigate this shortcoming, the combinations of time-based forgetting mechanisms, pruning and non-pruning strategies and linear and kernel functions, are utilized to ap-ply weights. A clustering technique is employed to detect the user's changing preferences. We apply our research approach to the DeliBook dataset. The goal of our experiments is to show that our algorithm that incorporates tempo-ral factors provides better recommendations than existing methods."

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A double case study applying action research methodology was conducted in two pharmaceutical preparation manufacturers in the Netherlands to improve their manufacturing systems by implementing time-based manufacturing (TBM) practices. Following the diagnosis phase, the situation of each Company was analysed and suitable improvement interventions were selected for implementation in the Case Companies. At the end of the action research project, semi-structured interviews were taken in each Company a year later, and the achieved results of the improvement programmes were collected and analysed. This research extends the existing theory of time-based competition and demonstrates that TBM practices apply also in the pharmaceutical preparation manufacturing industry. Furthermore, this study shows how to improve TBM practices and reduce the throughput time by providing the route for improvement and implementation. Although the first Case Company did not improve the core TBM practices and manufacturing performance, its infrastructure improved through the implementation of an ERP system and further enhancement of its quality management system, illustrating that the design of the infrastructure is a key factor to become a time-based competitor. The second Case Company succeeded to improve the 2 TBM practices and throughput processes resulting in the reduction of the order cycle time and increase of the delivery dependability. Based on the data of the two Case Companies, this study demonstrated the relationship between these two manufacturing performance parameters, which indicates that manufacturers may strive for both delivery speed and delivery reliability using the same improvement plan. Adopting TBM is a long journey of many years and needs a continuous improvement infrastructure.

The main research question pertains to the relationship between time-based manufacturing competence and business performance: Is there a positive relationship between time-based manufacturing competence and business performance. The objective of the study, therefore, is to examine the relationship between time -based manufacturing competence and business performance.

Distribution logistics plays a critical role in international companies that want to have more competence in the complex and global market. Today, most customers care more about whether the products can be in hand of them within expected time instead of how company delivery the products. Hence, time can be significant measurable indictor in distribution logistics. This thesis is to describe the effects of time based strategy in distribution logistics and how IKEA can gain competitive advantages by the utilization of time based strategy. The authors identify key elements in distribution logistics and find competitive advantages through researching the single case study-IKEA, and they are: speed, dependability and flexibility. Besides, the authors would provide some proposals to IKEA in order to optimize time-based strategy and gain competitive advantages.

Prospective memory (PM) refers to a person’s ability to remember to do something in the future. It is a complex behaviour that is essential for the daily functioning of young and old alike. Despite its importance in everyday life, few studies have sought to examine PM in a naturalistic way and even fewer have done so using school-aged children. The current study aimed to understand a particular form of time-based PM (TBPM), general TBPM, in children through the use of a novel naturalistic paradigm. In addition, the study aimed to add to the current PM literature by including an analysis of the circumstances surrounding a child’s prospective remembering. Results demonstrated that general TBPM was not significantly related to the parent-report Prospective Retrospective Memory Questionnaire for Children (PRMQC) or to the Memory for Intentions Screening Test for Youth (MISTY). Interestingly, general TBPM was not found to significantly relate to WM either. Descriptive analyses of the qualitative data demonstrated that no trigger rehearsals were most often responsible for children’s successful PM remembering. In contrast, when children forgot to complete their PM tasks, they most often reported being too busy with other things as the reason. The current findings provide preliminary support for the existence of a new sub-type of TBPM. They also call into question the utility of using measures like the MISTY and PRMQC to evaluate the ecological validity of new PM task paradigms. Consequently, future research should focus on validating current PM measures before using them to evaluate the ecological validity of new ones. Finally, it is also believed that the inclusion of qualitative measures assessing the contexts of PM retrieval have important implications for the effective development of future interventions for children who experience PM difficulties. / Graduate / 0621 / 0633 / 0620 / kdtalbot@uvic.ca

In this thesis, a time-based oversampling sigma-delta analog-to-digital converter (ADC) architecture is introduced. This system uses time, instead of voltage, as the analog variable for it quantizer, where the noise shaping process is realized by modulating the width of a variable-width digital pulse. The sigma-delta loop integrator, comparator, and subtractor are all time-based circuits and implemented by using only digital gates. The only voltage-based circuit is voltage-to-time Converter (VTC) which requires only a current source. No amplifier is required in the entire circuit. As a proof of concept, the simulation results for a prototype ADC incorporating this time-based sigma-delta ADC architecture is presented. / text

This thesis explores the study and design of an all-digital VCO-based ADC in a 65 nm CMOS technology. As the CMOS process enters the deep submicron region, the voltage-domain-based ADCs begins to suffer in improving their performance due to the use of complex analog components. A promising solution to improve the performance of an ADC is to employ as many as possible digital components in a time-domain-based ADC, where it uses the time resolution of an analog signal rather than the voltage resolution. In comparison, as the CMOS process scales down, the time resolution of an analog signal has found superior than the voltage resolution of an analog signal. In recent years, such time-domain-based ADCs have been taken an immense interest due to its inherent features and their design reasons. In this thesis work, the VCO-based ADC design, falls under the category of time-based ADCs which consists of a VCO and an appropriate digital processing circuitry. The employed VCO is used to convert a voltage-based signal into a time signal and thereby it also acts as a time-based quantizer. Then the resulting quantized-time signal is converted into a digital signal by an appropriate digital technique. After different architecture exploration, a conventional VCO-based ADC architecture is implemented in a high-level model to understand the characteristic behaviour of this time-based ADC and then a comprehensive functional schematic-level is designed in reference with the implemented behavioural model using cadence design environment. The performance has been verified using the mixed-levels, of transistor and behavioural-levels due to the greater simulation time of the implemented design. ADC’s dynamic performance has been evaluated using various experiments and simulations. Overall, the simulation experiments showed that the design was found to reach an ENOB of 4.9-bit at 572 MHz speed of sample per second, when a 120 MHz analog signal is applied. The achieved peak performance of the design was a SNR of 40 dB, SFDR of 34 dB and an SNDR of 31 dB over a 120 MHz BW at a 1 V supply voltage. Without any complex building blocks, this VCO-based all-digital ADC design provided a key feature of inherent noise shaping property and also found to be well compatible at the deep submicron region.

At present, it is necessary to protect sensitive data against abuse, but also allow au-thorized persons to change these data. To increase the security of logging for authorized persons we often introduce a two-factors authentication, where the first step is verification of the user's identity and in a second step is required to insert a one-time password called OTP. This thesis deals with implementation of OTP and integration into the selected sys-tem. It also includes test and verification of the functionality of the selected solution.

Tato práce se zabývá běžnými problémy časových politik, které jsou využívány v rámci procesu přihlašování uživatelů. Jsou rozebrána řešení v některých jiných současných systémech. Dále je čtenáři představen projekt pro správu identit FreeIPA, autor se zaměřuje hlavně na správu uživatelů a politiky pro jejich autorizaci. Je také představen projekt SSSD se zaměřením na jeho propojení se systémem FreeIPA. Po vytvoření návrhu řešení problému časových politik je tento návrh implementován do systémů FreeIPA a SSSD.