This thesis focuses on designing Low-Density Parity-Check (LDPC) codes for forward-error-correction. The target application is real-time multimedia communications over packet networks. We investigate two code design issues, which are important in the target application scenarios, designing LDPC codes with low decoding latency, and constructing capacity-approaching LDPC codes with very low error probabilities. On designing LDPC codes with low decoding latency, we present a framework for optimizing the code parameters so that the decoding can be fulfilled after only a small number of iterative decoding iterations. The brute force approach for such optimization is numerical intractable, because it involves a difficult discrete optimization programming. In this thesis, we show an asymptotic approximation to the number of decoding iterations. Based on this asymptotic approximation, we propose an approximate optimization framework for finding near-optimal code parameters, so that the number of decoding iterations is minimized. The approximate optimization approach is numerically tractable. Numerical results confirm that the proposed optimization approach has excellent numerical properties, and codes with excellent performance in terms of number of decoding iterations can be obtained. Our results show that the numbers of decoding iterations of the codes by the proposed design approach can be as small as one-fifth of the numbers of decoding iterations of some previously well-known codes. The numerical results also show that the proposed asymptotic approximation is generally tight for even non-extremely limiting cases. On constructing capacity-approaching LDPC codes with very low error probabilities, we propose a new LDPC code construction scheme based on $2$-lifts. Based on stopping set distribution analysis, we propose design criteria for the resulting codes to have very low error floors. High error floors are the main problems of previously constructed capacity-approaching codes, which prevent them from achieving very low error probabilities. Numerical results confirm that codes with very low error floors can be obtained by the proposed code construction scheme and the design criteria. Compared with the codes by the previous standard construction schemes, which have error floors at the levels of $10^{-3}$ to $10^{-4}$, the codes by the proposed approach do not have observable error floors at the levels higher than $10^{-7}$. The error floors of the codes by the proposed approach are also significantly lower compared with the codes by the previous approaches to constructing codes with low error floors.

This is a M. Eng. degree project at Uppsala University carried out at the Forsmark nuclear power plant in Sweden. The purpose of it is to compare the two codes RELAP5 and TRACE during transient changes in mass flow against experiment. The change in mass flow will create a pressure wave and generate pipe loads. RELAP5 is a transient analysis code used to model thermal hydraulic systems. TRACE is an effort to combine the previous codes TRAC-B, TRAC-P, RAMONA and RELAP5. Both RELAP5 and TRACE has been compared to experiments. These comprise two abrupt valve closures, the closure of an inertial swing check valve (a flapper disc which closes when the flow is reversed) and a pump start and stop. Both RELAP5 and TRACE conforms well to the experiments with the abrupt valve closures. The check valve closes faster in the calculations compared to the experiment, both for RELAP5 as with TRACE. The amplitude of the pressure wave from the closure of the inertial swing check valve is lower compared to the experiment in both RELAP5 and TRACE. Numerical disturbances become visual as very high amplitudes in the time history diagram of the force in TRACE. The check valve oscillates between its open and closed position in RELAP5, but not in TRACE. Both RELAP5 and TRACE conforms well to the pump start. The mass flow decreases faster in both RELAP5 and TRACE compared to the pump stop.

This thesis focuses on designing Low-Density Parity-Check (LDPC) codes for forward-error-correction. The target application is real-time multimedia communications over packet networks. We investigate two code design issues, which are important in the target application scenarios, designing LDPC codes with low decoding latency, and constructing capacity-approaching LDPC codes with very low error probabilities. On designing LDPC codes with low decoding latency, we present a framework for optimizing the code parameters so that the decoding can be fulfilled after only a small number of iterative decoding iterations. The brute force approach for such optimization is numerical intractable, because it involves a difficult discrete optimization programming. In this thesis, we show an asymptotic approximation to the number of decoding iterations. Based on this asymptotic approximation, we propose an approximate optimization framework for finding near-optimal code parameters, so that the number of decoding iterations is minimized. The approximate optimization approach is numerically tractable. Numerical results confirm that the proposed optimization approach has excellent numerical properties, and codes with excellent performance in terms of number of decoding iterations can be obtained. Our results show that the numbers of decoding iterations of the codes by the proposed design approach can be as small as one-fifth of the numbers of decoding iterations of some previously well-known codes. The numerical results also show that the proposed asymptotic approximation is generally tight for even non-extremely limiting cases. On constructing capacity-approaching LDPC codes with very low error probabilities, we propose a new LDPC code construction scheme based on $2$-lifts. Based on stopping set distribution analysis, we propose design criteria for the resulting codes to have very low error floors. High error floors are the main problems of previously constructed capacity-approaching codes, which prevent them from achieving very low error probabilities. Numerical results confirm that codes with very low error floors can be obtained by the proposed code construction scheme and the design criteria. Compared with the codes by the previous standard construction schemes, which have error floors at the levels of $10^{-3}$ to $10^{-4}$, the codes by the proposed approach do not have observable error floors at the levels higher than $10^{-7}$. The error floors of the codes by the proposed approach are also significantly lower compared with the codes by the previous approaches to constructing codes with low error floors.

The Chinese Nationalist Party's (KMT) assets referendum and the anti-corruption referendum took place alongside the Legislative election in January 2008. The same year, the other national referendums on joining UN and returning to UN were held with the Presidential election in March. In the Legislative election, while 59 percent of electorate voted, turnout rate for the referendums are surprisingly low to 26 percent. In the Presidential election, in spite of a high turnout rate of 76 percent, turnout rate for the referendums are merely 36 percent. What is the reason for people to vote in elections but not on referendums? Partisanship probably explains people¡¦s turnout on referendum, but I suspect that there are more factors. This research provides a framework and a model of voting participation in referendum. Base on my analysis of Taiwan¡¦s Election and Democratization Study(TEDS), I find the following: First, Partisanship is the only factor which affect the referendums in the Legislative election and the Presidential election. However, people¡¦s partisanship reflects their values and leads to take or not to take referendum ballots. Other important factors of referendum voting participation are political interest, identity of Taiwanese or Chinese, What newspaper is used to read, unification-independence issue and perspectives on the relation between President and Legislative Yuan. Second, with identity of Taiwanese or Chinese and unification-independence issue, we could infer that attitudes about referendum issue affect referendum voting participation behavior. Finally, by the electors that prefer to check and balance between the executive power and the legislative power likely decide to take referendum ballots, we could assume that some voters who realize and support referendum system intend to vote on referendum.

The aim of this study attempts to explore in which circumstance users would self-disclosure on Facebook with check-in behavior by considering extraversion and narcissism as psychological factors. Furthermore, in order to examine the relationships between different behaviors on Facebook, self-disclosure, exhibitionism and check-in intensity, this study used exhibitionism as the mediator to discuss if users¡¦ cognition of exhibitionism toward check-in would influence their attempt on check-in and clarify the attributes which make users behave in this way. Finally, a framework is proposed based on the results. Purposive sampling was used in the study. Questionnaire data were collected by the Internet and totally received 523 valid respondents. The study used LISREL structural equation models to test goodness of fit, validity, and furthermore adopted full model to examine the hypotheses. The results showed that the extraversion has an impact on the extent of self-disclosure on Facebook; however, narcissism does not have a significant effect on self-disclosure. As for the relationship between self-disclosure, exhibitionism and check-in intensity, self-disclosure would directly influence the attempts at check-in intensity. On the other hand, exhibitionism would also make self-disclosure have an impact on check-in intensity as a partial mediator.

Introduction The number of the people who needs dialysis escalates rapidly year each. The rising cost of dialysis is relative. Because Bureau National Health Insurance endures the co-payment of hemodialysis, patients have freedom of choice. Two critical factors that influence patient¡¦s decision in medical care are access and quality. Facing pressure from competition, many hemodialysis service providers believe that high quality service will retain patients to return as well as maintain a healthy physician-patient relationship. Therefore, they apply many quality management tools, which also include service pathways. There are few investigations that discuss service pathways. Thus, this research constructs a model to analyze the effect of service pathways in hemodialysis service providers. Method From Nov. 1, 2003 to Dec. 31, 2004, the researcher interviewed hemodialysis nurses to develop flow chart, customer encounter, and check list for hemodialysis. We also collected the check list records of the hemodialysis patients to examine the effect. Conclusion First, the construction of total service pathways comprised three critical interlocking phases: flow chart, customer encounter, and check list. After that we shall evaluate and correct them continuously. Secondly, the researcher found that most patients are routine members, and come from long-term care center and respiratory care ward (RCW). Thirdly, the indicators influencing hemodialysis results and error incidents were steady. Finally, in the value-added services dimensions, the indicators of nurses¡¦ performance on greeting and asking patients if they want to have a meal were significant, but the indicators of telephone and inpatient interview were unfavorable.

The purpose of this study was to examine the impact of criminal background checks on the selection of school volunteers as reported by human resource professionals in selected Texas public school districts. Ninety Texas school districts were randomly selected for this study, and results were categorized by the size of the school district based on student population. Survey responses were analyzed using descriptive and inferential statistics. A Chi-square analysis was performed to determine if there were significant differences (p ? 0.05) in responses to research questions based on size of the school district. Findings in the study included the following: 1. There was no difference in the school district approach to policy and procedure development based on the size of the school district as it pertained to criminal background checks of school volunteers. 2. There was no difference in response rate based on the size of the school district regarding type of offense, number of offenses, adjudication process, and type of criminal history data search. 3. There was a significant difference (p ? 0.05) in approach between largesized and small-sized school districts regarding the acceptable timeframe concerning recency of offense on a volunteer criminal history record. 4. There was no difference in response rate based on the size of the school district regarding the effectiveness of criminal background check procedures in eliminating potential volunteers who might pose a threat or risk to teachers, staff, and students. The following are recommendations for further study: 1. A similar study could assess the responses from teachers, staff, and/or students to determine if these different education categories possess different perceptions regarding the impact of criminal background checks on school volunteers. 2. A further study could analyze the specific written policies of school districts and determine the decision criteria for each level of offense. 3. This study focused on school volunteers. A research study could specifically focus on the impact of criminal background checks on parent volunteers, or conversely be more general, focusing on the impact of criminal background checks on professional or auxiliary employees.

A family of low-density lattice codes (LDLC) is studied based on Construction-A for lattices. The family of Construction-A codes is already known to contain a large capacity-achieving subset. Parallels are drawn between coset non-binary low-density parity-check (LDPC) codes and nested low-density Construction-A lattices codes. Most of the related research in LDPC domain assumes optimal power allocation to encoded codeword. The source coding problem of mapping message to power optimal codeword for any LDPC code is in general, NP-hard. In this thesis, we present a novel method for encoding and decoding lattice based on non-binary LDPC codes using message-passing algorithms. / text

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This bachelor degree work explores the interrelation between print and surface in fashion design and aims to investigate the expressional possibilities in merging of techniques. With focus on creating an irregular surface through embroidery and fringing, three-dimensional expressions are created, resulting in an illusion of depth and movement within the motifs. The work is textile-driven, hence the main focus has been to find materials, applicational techniques and motifs that interact with each other without conflicts. Through the use of heat sensitive yarns within the transfer printing process a clear relationship between texture and motif occur where the different aspects affect each other and are equally important for the final visual expression. It is the heat-press used to transfer print from paper to surface that is the most vital step of the process. This work strives to propose a transposed order of applying techniques within a design process. Whilst the act of embellishing existing prints has been investigated by a range of designers, this project propose an order where the print is added post additive surface-manipulation. Therefore this work is to be seen as a suggestion of new ways of approaching the use of prints within the fashion field. Balancing between fashion design and textile design, the collection is based on generic prints and shapes which are affected by the surface manipulations used.