Realization of Differentiated Quality of Service for Wideband Code Division Multiple Access Core Network

The development of 3G (the 3rd generation telecommunication) value-added services brings higher requirements of Quality of Service (QoS). Wideband Code Division Multiple Access (WCDMA) is one of three 3G standards, and enhancement of QoS for WCDMA Core Network (CN) becomes more and more important for users and carriers. The dissertation focuses on enhancement of QoS for WCDMA CN. The purpose is to realize the DiffServ (Differentiated Services) model of QoS for WCDMA CN. Based on the parallelism characteristic of Network Processors (NPs), the NP programming model is classified as Pool of Threads (POTs) and Hyper Task Chaining (HTC). In this study, an integrated programming model that combines both of the two models was designed. This model has highly efficient and flexible features, and also solves the problems of sharing conflicts and packet ordering. We used this model as the programming model to realize DiffServ QoS for WCDMA CN. ^ The realization mechanism of the DiffServ model mainly consists of buffer management, packet scheduling and packet classification algorithms based on NPs. First, we proposed an adaptive buffer management algorithm called Packet Adaptive Fair Dropping (PAFD), which takes into consideration of both fairness and throughput, and has smooth service curves. Then, an improved packet scheduling algorithm called Priority-based Weighted Fair Queuing (PWFQ) was introduced to ensure the fairness of packet scheduling and reduce queue time of data packets. At the same time, the delay and jitter are also maintained in a small range. Thirdly, a multi-dimensional packet classification algorithm called Classification Based on Network Processors (CBNPs) was designed. It effectively reduces the memory access and storage space, and provides less time and space complexity. ^ Lastly, an integrated hardware and software system of the DiffServ model of QoS for WCDMA CN was proposed. It was implemented on the NP IXP2400. According to the corresponding experiment results, the proposed system significantly enhanced QoS for WCDMA CN. It extensively improves consistent response time, display distortion and sound image synchronization, and thus increases network efficiency and saves network resource.^

Fair price and its effect on willingness to purchase

The purpose of the present research is to demonstrate the influence of a fair price (independent of the subjective evaluation of the price magnitude) on buyers' willingness to purchase. The perceived fairness of a price is conceived to have three components: perceived equity, perceived need, and inferred compliance of the seller to the process rules of pricing. These components reflect the Theories of Distributive Justice (as adjusted for conditions of need) and Procedural Justice.^ The effect of the three components of a fair price on willingness to purchase is depicted in a theoretically causal chain model. Based on the Theories of Dissonance and Attribution, conditions of inequity and need activate concerns for Procedural Justice. Under conditions of inequity and need, buyers tend to infer that the seller has not complied with the generally accepted pricing practices, thus violating the social norms of Procedural justice. Inferred violations of Procedural Justice influence the buyer's attitude toward the seller. As predicted by the Theory of Reasoned Action, attitude is then positively related to willingness to purchase.^ The model was tested with a survey-based experiment conducted with 408 respondents. Two levels of both equity and need were manipulated with scenarios, a common research method in studies of Distributive and Procedural Justice. The data were analyzed with a structural equation model using LISREL. Although the effect of the "need" manipulation was insignificant, the results indicated a good fit of the model (Chi-square = 281, Degrees of Freedom = 104, Goodness of Fit Index =.924). The conclusion is that the fairness of a price does have a significant effect on willingness to purchase, independent of the subjective evaluation of the objective price. ^

Fair and QoS-oriented resource management in heterogeneous networks

In this paper, a heterogeneous network composed of femtocells deployed within a macrocell network is considered, and a quality-of-service (QoS)-oriented fairness metric which captures important characteristics of tiered network architectures is proposed. Using homogeneous Poisson processes, the sum capacities in such networks are expressed in closed form for co-channel, dedicated channel, and hybrid resource allocation methods. Then a resource splitting strategy that simultaneously considers capacity maximization, fairness constraints, and QoS constraints is proposed. Detailed computer simulations utilizing 3GPP simulation assumptions show that a hybrid allocation strategy with a well-designed resource split ratio enjoys the best cell-edge user performance, with minimal degradation in the sum throughput of macrocell users when compared with that of co-channel operation.

A Market Study of Organic and Fair Trade Coffee in Bolivia

The purpose of this research is to study the commercialization of Fairtrade and Organic coffee in the Bolivia. Fairtrade and Organic coffee are alternative trade systems designed to promote the equitable and environmentally sustainable production of coffee. However, these alternative trading systems often fail to meet these goals. The producers and environment these systems are intended to protect remain marginalized. These failures are due to a number of local institutions. In order to better understand these institutions, this research conducted interviews of various stakeholders including producers, cooperative leaders, organic/Fair Trade certifiers, government agencies and private buyers. All these stakeholders influence the success of the alternative trade systems. By better understanding how these stakeholders impact the commercialization of coffee in Bolivia; new policies can be develop to improve the outcomes of alternative trade, to benefit both producers and the environment. This is especially critical in Bolivia because of the environmentally sensitive area in which coffee is grown, the potentially damaging impact of coca on the region and, the devastating economic impact to farmers.