The performance of multiple input single output (MISO) broadcast channels is strongly dependent on the availability of channel side information (CSI) at the transmitter. In many practical systems, CSI may be available to the transmitter only in a corrupted and incomplete form. It is natural to assume that the flaws in the CSI are random and can be represented by a probability distribution over the channel. This work is concerned with two key issues concerning MISO broadcast systems with random CSI: performance analysis and system design. First, the impact of noisy channel information on system performance is investigated. A simple model is formulated where the channel is Rayleigh fading, the CSI is corrupted by additive white Gaussian noise and a zero forcing precoder is formed by the noisy CSI. Detailed analysis of the ergodic rate and outage probability of the system is given. Particular attention is given to system behavior at asymptotically high SNR. Next, a method to construct precoders in a manner that accounts for the uncertainty in the channel information is developed. A framework is introduced that allows one to quantify the tradeoff between the risk (due to the CSI randomness) that is associated with a precoder and the resulting transmission rate. Using ideas from modern portfolio theory, the risk-rate problem is modified to a tractable mean-variance optimization problem. Thus, we give a method that allows one to efficiently find a good precoder in the risk-rate sense. The technique is quite general and applies to a wide range of CSI probability distributions.

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Information delivery via the web has become very popular. Along with a growing user population, systems increasingly are supporting content that changes frequently, personalised information, and differentiation and choice. This thesis is concerned with the design and evaluation of resource management strategies for such systems. An architecture that provides scalability through caching proxies is considered. When a cached page is updated at the server, the cached copy may become stale if the server is not able to transmit the update to the proxies immediately. From the perspective of the server, resources are required to transmit updates for cached pages and to process requests for pages that are not cached. Analytic results on how the available resources should be managed in order to minimise staleness-related cost are presented. An efficient algorithm that the server can use to determine the set of pages that should be cached and a policy for transmitting updates for these pages are also presented. We then apply these results to page fragments, a technique that can provide increased efficiency for delivery of personalised pages.

This dissertation deals with the problem of scheduling in wireless MIMO (Multiple-Input Multiple-Output) downlink systems. The focus is on the large-scale systems when the number of subscribers is large. In part one, the problem of user selection in MIMO Broadcast channel is studied. An efficient user selection algorithm is proposed and is shown to achieve the sum-rate capacity of the system asymptotically (in terms of the number of users), while requiring (i)~low-complexity precoding scheme of zero-forcing beam-forming at the base station, (ii)~low amount of feedback from the users to the base station, (iii)~low complexity of search. Part two studies the problem of MIMO broadcast channel with partial Channel State Information (CSI) at the transmitter. The necessary and sufficient conditions for the amount of CSI at the transmitter (which is provided to via feedback links from the receivers) in order to achieve the sum-rate capacity of the system are derived. The analysis is performed in various singnal to noise ratio regimes. In part three, the problem of sum-rate maximization in a broadcast channel with large number of users, when each user has a stringent delay constraint, is studied. In this part, a new definition of fairness, called short-term fairness is introduced. A scheduling algorithm is proposed that achieves: (i) Maximum sum-rate throughput and (ii) Maximum short-term fairness of the system, simultaneously, while satisfying the delay constraint for each individual user with probability one. In part four, the sum-rate capacity of MIMO broadcast channel, when the channels are Rician fading, is derived in various scenarios in terms of the value of the Rician factor and the distribution of the specular components of the channel.

Information delivery via the web has become very popular. Along with a growing user population, systems increasingly are supporting content that changes frequently, personalised information, and differentiation and choice. This thesis is concerned with the design and evaluation of resource management strategies for such systems. An architecture that provides scalability through caching proxies is considered. When a cached page is updated at the server, the cached copy may become stale if the server is not able to transmit the update to the proxies immediately. From the perspective of the server, resources are required to transmit updates for cached pages and to process requests for pages that are not cached. Analytic results on how the available resources should be managed in order to minimise staleness-related cost are presented. An efficient algorithm that the server can use to determine the set of pages that should be cached and a policy for transmitting updates for these pages are also presented. We then apply these results to page fragments, a technique that can provide increased efficiency for delivery of personalised pages.

This dissertation deals with the problem of scheduling in wireless MIMO (Multiple-Input Multiple-Output) downlink systems. The focus is on the large-scale systems when the number of subscribers is large. In part one, the problem of user selection in MIMO Broadcast channel is studied. An efficient user selection algorithm is proposed and is shown to achieve the sum-rate capacity of the system asymptotically (in terms of the number of users), while requiring (i)~low-complexity precoding scheme of zero-forcing beam-forming at the base station, (ii)~low amount of feedback from the users to the base station, (iii)~low complexity of search. Part two studies the problem of MIMO broadcast channel with partial Channel State Information (CSI) at the transmitter. The necessary and sufficient conditions for the amount of CSI at the transmitter (which is provided to via feedback links from the receivers) in order to achieve the sum-rate capacity of the system are derived. The analysis is performed in various singnal to noise ratio regimes. In part three, the problem of sum-rate maximization in a broadcast channel with large number of users, when each user has a stringent delay constraint, is studied. In this part, a new definition of fairness, called short-term fairness is introduced. A scheduling algorithm is proposed that achieves: (i) Maximum sum-rate throughput and (ii) Maximum short-term fairness of the system, simultaneously, while satisfying the delay constraint for each individual user with probability one. In part four, the sum-rate capacity of MIMO broadcast channel, when the channels are Rician fading, is derived in various scenarios in terms of the value of the Rician factor and the distribution of the specular components of the channel.

Due to high frequency and occurrence of chronic kidney diseases in Taiwan, as well as the low public awareness, this research aims to explore the knowledge construction process of Hemodialysis in health broadcasting programs from a health communication point of view. This research intended to answer the following questions: 1) What are health radio program audience types? 2) How does the knowledge on hemodialysis differ among audiences? 3) What is the knowledge construction process among audience in regards to hemodialysis? Data were collected by ten episodes of the Kaohsiung Police Ration Station¡¦s ¡§Medical Network¡¨ program for a six month period (January ~ June 2011). This research has utilized content analysis method on the audience type, quantitative description on questions identified by the audience and qualitative methods to summarize and interpret the audience¡¦s knowledge construction process on hemodialysis. The results showed that the main audiences for health broadcast programs are mostly male, age 31 to 50 years, holding profession as drivers, service personnel and potential patients. Among them, the potential patients and their family members most often times ask diagnostic questions, falling into the compelled group in seek of knowledge. Those who have not been diagnosed with the disease often times bring up knowledge confirmation questions, belonging to the proactive knowledge chaser group. These two groups also demonstrated different hemodialysis knowledge construction processes. While the radio program host plays the role of knowledge enhancer to the diagnostic-need group (potential patients), the role transfers to a knowledge transformation model for the knowledge confirmation group (non-patients). Participating physicians follow the treatment process of ¡V examination, diagnosis and treatment to deliver information. The research process shall provide broadcasters or other media professionals a best practice on how the audience absorbs information - to study the distribution and motives of the audience and to deliver the knowledge of health and illnesses.

Through out its history, traditional radio station has left part of its listener unsatisfied. Social media is a hot new media, that allows a group of stranger come together because of the same interest; share and exchange information. A lot of traditional media try to join this new media but for radio stations it¡¦s still at a early stage trying to uncover user¡¦s need without a clear direction. This research is a first attempts trying to discuss the relationship between social media user behavior and the traditional radio stations. This research attempts to discuss the relationship between social media user behavior and the operation of radio management. By analyzing radio station¡¦s Facebook fans page in order to understand users motivation, behavior and reasons of satisfaction. Through that hoping to understand user¡¦s need and design radio station base on their needs. Further reinforce the likeable towards the fan page even raise the loyalty the fans have for the station Assume user behavior will affect lever of satisfactory, look through the relationship between user behavior and lever of satisfactory, in the six behavior include pressing ¡§like¡¨, ¡§leave a massage¡¨, ¡§share¡¨, ¡§chat¡¨,¡¨read message¡¨,¡¨event¡¨. Four of then are related with level of satisfactory. Research design and method, the questions are structure to discuss questions includes: --Discuss what actions will satisfy the user on the radio station¡¦s Facebook fan page --Analyze what are the actions that are satisfying for the users on the radio station¡¦s Facebook fan page. By using surveys, analyzing data, and discussion. This result shows, the user on Facebook can receive satisfaction and willing to recommend it to friends.

The management strategies of the religious televisions in Taiwan-a value chain analysis

In this dissertation, we focus on the study of the partial sorting (generalized sorting) problem and the initialization problem. The partial sorting problem is to find the first k smallest (or largest) elements among n input elements and to report them in nondecreasing (or nonincreasing). The initialization problem on a multiprocessor system is to assign each of n input elements a unique identification number, from 1 to n. This problem can be regarded as a special case of the sorting problem in which all input elements have the same value. We propose some algorithms for solving these problems. The main result is to give precise analysis for these algorithms. On the traditional model, we modify two algorithms, based on insertion sort and quicksort, to solve the partial sorting problem. Our analysis figures out the whole race between the two partial sorting algorithms and shows that the partial insertion sort algorithm obtains the leading position from k = 1 (the beginning) until k 3 5pn. After that, the partial quicksort algorithm will take the leading position on the way to the end. We also extend the partial sorting problem on the Single-Hop wireless network with collision detection (WNCD) model. The extension fits in with the wireless trend and may be a foundation for studying divide-and-conquer. With the repeat maximum finding scheme, we propose a partial sorting algorithm and prove that its average time complexity is (k + log (n − k)). For the initialization problem on the WNCD model, we can invoke the sorting algorithms directly for solving it. However, those sorting algorithms would not be better than the method of building a partition tree. We show that the partition tree method requires 2.88n time slots in average. After reconstructing and analyzing the method, we improve the result from 2.88n to 2.46n.