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Cognitive radio (CR) is a promising technique to improve spectrum efficiency for wireless communications. This thesis focuses on the resource allocation in two kinds of CR networks (CRNs), traditional CRNs (TCRNs) and cooperative CRNs (CCRNs). In TCRNs, CR sources and destinations communicate directly. By exploring the heterogeneity among CRs, a prioritized CSMA/CA is proposed for demand-matching spectrum allocation. A distributed game is formulated and no-regret learning is adopted to solve the game. Simulation results indicate increase on the number of satisfied CRs. In CCRNs, some nodes are selected as relays to assist the communication. A two-layer auction game is proposed with the first layer performing spectrum allocation and relay formation, and the second layer performing relay allocation. These two layers interact and jointly solve the resource allocation problem. Simulation results show that, compared to counterparts, both the network throughput and convergence time can be improved.

Hybrid physiological models are being increasingly used to assess productivity, carbon sequestration, water and nutrient use and environmental impacts of management decisions. Users include forest managers, politicians, environmental agencies and scientists. However a wider use of these models has been prevented as a result of an incomplete understanding of the mechanisms regulating carbon allocation, nutrient availability in soils and nutrient uptake by trees. On-going innovation in clonal forestry, genetic improvement and vegetation management techniques is also poorly represented in hybrid models. This thesis examines means to represent nutrition and genotype-nutrition interactions in productivity physiological hybrid models. Nutrient limitations and growth differences between genotypes were hypothesized to operate through key physiological processes: photosynthesis, carbon allocation and nutrient internal cycling. In order to accomplish the aims of the study both greenhouse and field experimentation were carried out. In a first experiment, responses of photosynthesis (A) to intercellular CO₂ concentration (Ci) were measured in a fast- and a slow-growing clone of Pinus radiata D. Don cultivated in a greenhouse in a factorial combination of nitrogen and phosphorus supply, and analyzed using the biochemical model of leaf photosynthesis described by Farquhar et al. (1980). There were significant positive linear relationships between the parameters, Vcmax, Jmax, Tp and both foliar nitrogen (Na) and phosphorus (Pa) concentration on an area basis. The study showed that the effects of nitrogen and phosphorus supply on photosynthesis were statistically independent and that the photosynthetic behaviour of the two clones was equivalent. In a similar study, gas exchange and chlorophyll fluorescence were simultaneously measured to determine internal transfer conductance (gm) based on the "constant J method". Transfer conductance may pose significant limitations to photosynthesis which may be differentially affected by nutrition and genotype in Pinus radiata. Values of gm were similar to those of stomatal conductance (gs) and their ratio (gm / gs) was not influenced by nutrient supply or clone being on average (±1 SE) 1.22 ±0.04. Relative mesophyll limitations (LM, 16%) to photosynthesis were marginally greater than those imposed by stomata (LS, 13%), and together smaller than the relative limitations posed to photosynthesis by biochemical processes (LB, 71%). The CO₂ concentration in the intercellular air spaces (Ci) was (±1 SE) 53 ±3 µmol mol-1 lower than in the atmosphere (Ca) while CO₂ concentration in the chloroplasts (Cc) was (±1 SE) 48 ±2 µmol mol-1 less than Ci. Values of LS, LM and LB and CO₂ diffusion gradients posed by gs (Ca-Ci) and gm (Ci-Cc) did not change with nutrient supply or clone. In a third experiment, one-year old Pinus radiata cuttings from four genotypes were cultivated in silica sand with a factorial combination of nitrogen (N0=1.43 and N1=7.14 mM) and phosphorus (P0=0.084 and P1=0.420 mM) supply for 24 months. N supply was enriched with ¹⁵N to 2.5⁰/₀₀ (labelled N) during the first year, then plants transferred to clean sand and cultivated for another year with ¹⁵N at levels close to natural abundance (0.3664899 atom percent ¹⁵N, δ¹⁵N 0.5115 ⁰/₀₀) provided by the source of N in nutrient solution applied during the second year. Recovery of labelled and unlabelled N was used to estimate N remobilization. N remobilization scaled with plant growth, N content and N and P supply. In relative terms, 65% of all stored N was remobilized in the high-nutrient supply regime compared to 42-48% at lower N and P addition rates. Most N remobilization occurred during spring-summer (77%), coincidently with the largest proportion of needle development (80%), indicating that N remobilization was driven by sink-strength. Foliage was by far the main source for internal cycling while roots were the main sink (40%). Clones exhibited differences in N remobilization capacity, but these differences were completely explained by the size of the N pool before remobilization took place, indicating that N remobilization performance was similar among clones. In a fourth study, four clones were cultivated in silica sand with a factorial combination of nitrogen and phosphorus supply for ten months, and patterns of carbon allocation examined using a carbon balance approach. Gross-primary productivity (GPP) scaled mainly with nitrogen but also with phosphorus supply. The fraction of GPP (GPP = ANPP + APR + TBCA) allocated to above-ground components (ANPP) increased with N and P supply at the expense of total-below ground C allocation (TBCA) with no apparent effect on the fraction of GPP partitioned to above-ground plant respiration (APR). Carbon use efficiency (NPP:GPP) scaled with nutrient supply, being 0.42 in the low-nutrient supply regime compared to 0.51 in the high-nutrient supply regime, suggesting that in poor fertility environments a larger proportion of the C budget is respired compared to the net productivity. Fast-growing clones allocated about 2-4% more carbon to above-ground components (ANPP) at the expense of carbon allocated below-ground (TBCA) with no effect on carbon respired above-ground (APR), indicating that faster-growing genotypes allocate more carbon to leaf area which may compound and increase overall GPP over time. The field component of this thesis was conducted in a subset of locations where ENSIS (formerly New Zealand Forest Research Institute) had established trials to test the influence of species, soil disturbance and plant nutrition on sustainability indicators. Plots were small in size (3 m × 3 m) with trees spaced at 0.5 m × 0.5 m (40 000 trees ha-1) with nine measurement trees surrounded by a two-row buffer. All sites were planted in winter 2001 and harvested in spring 2005. The aim of this pilot study was to examine patterns of carbon allocation during the fourth year after planting in control and fertilized mini-plots of Pinus radiata in five sites with contrasting climate and soil conditions in the South Island of New Zealand. The study showed that the fraction of gross-primary productivity allocated belowground increased as the soil C:N ratio increased. However, these results should be interpreted with caution due to the unusual nature of the trial and the reduced number of sites studied. Two existing physiological models were selected for the discussion in this thesis (3-PG, Landsberg and Waring 1997; canopy net carbon exchange model, Whitehead et al. 2002). Potential improvements for the nutritional component of 3-PG comprise: accounting for reductions in carbon use efficiency (NPP:GPP) in poor-fertility environments, adding a preliminary fertility modifier (FN, 0-1) driven by soil C : N ratio and soil N, adding a preliminary relationship between carbon allocation to roots and the soil C : N ratio and representing faster-growing genotypes by increasing their leaf area but not their photosynthetic performance. The canopy net carbon exchange model (NCE) combines the coupled model of leaf photosynthesis - stomatal conductance described by Leuning (1995) with canopy structure and a water balance model to scale carbon assimilation from leaves to canopies. Potential improvements to account for nutrient deficiencies in the leaf model by Leuning (1995), comprise using nutrient ratios to discriminate nitrogen (Na/Pa < 23 mol mol-1) from phosphorus deficiencies (Na/Pa > 23 mol mol-1), adding relationships between photosynthetic model parameters Vcmax and Jmax to Pa, and correcting the estimation of photosynthetic parameters Vcmax and Jmax by accounting for transfer conductance (gm). The canopy net carbon exchange model may be also modified to account for carbon-use efficiency, carbon allocation to roots and genotype in a similar form to that proposed for 3-PG. The results previously outlined provide a preliminary framework to represent tree and soil nutrition in physiological hybrid productivity models.

Recent research results have shown that the MIMO wireless communication architecture is a promising approach to achieve high bandwidth efficiencies. MIMO wireless channels can be simply defined as a link for which both the transmitting and receiving ends are equipped with multiple antenna elements. Adaptive modulation and power allocation could be used to further improve the performance of MIMO systems. This thesis focuses on developing a fast and high performance power allocation algorithm. Three power allocation algorithms are proposed in this thesis and their performances are compared in various system sizes and transceiver architectures. Among the three algorithms proposed in this thesis, the fast algorithm may be considered as the best power allocation algorithm since the performance of the fast algorithm is almost as good as the fullsearch (optimal)algorithm and the mean processing time is considerably less than the fullsearch algorithm. The fast algorithm achieves about 97.6% agreement with the optimal throughput on average. In addition, the time taken to find the power scaling factors using the fullsearch algorithm is about 2300 times longer than the processing time of the fast algorithm in a 6 x 6 system when the SNR is 20dB. As an extension to the power allocation process, excess power allocation methods are introduced. Excess power is the unused power during the power allocation process. The power allocation algorithm allocates power to each received SNR to maximize the throughput of the system whereas the excesspower allocation distributes the excess power to each SNR to improve both the instantaneous and temporal behavior of the system. Five different excess power allocation methods are proposed in this thesis. These methods were simulated in the Rayleigh fading channel with different Doppler frequencies, fD = 10Hz,50Hz and 100Hz, where the ACF of the channel coefficients are given by the Jakes' model. The equal BER improvement method showed a slightly better performance than the other methods. The equal BER improvement method enables the system to maintain the power scaling factors without sacrificing QoS for 19.6 ms on average when the maximum Doppler shift is 10Hz.

Next generation wireless communication networks are expected to provide ubiquitous high data rate coverage and support heterogeneous wireless services with diverse quality-of-service (QoS) requirements. This translates into a heavy demand for the spectral resources. In order to meet these requirements, Orthogonal Frequency Division Multiple Access (OFDMA) has been regarded as a promising air-interface for the emerging fourth generation (4G) networks due to its capability to combat the channel impairments and support high data rate. In addition, OFDMA offers flexibility in radio resource allocation and provides multiuser diversity by allowing subcarriers to be shared among multiple users. One of the main challenges for the 4G networks is to achieve high throughput throughout the entire cell. Cooperative relaying is a very promising solution to tackle this problem as it provides throughput gains as well as coverage extension. The combination of OFDMA and cooperative relaying assures high throughput requirements, particularly for users at the cell edge. However, to fully exploit the benefits of relaying, efficient relay selection as well as resource allocation are critical in such kind of network when multiple users and multiple relays are considered. Moreover, the consideration of heterogeneous QoS requirements further complicate the optimal allocation of resources in a relay enhanced OFDMA network. Furthermore, the computational complexity and signalling overhead are also needed to be considered in the design of practical resource allocation schemes. In this dissertation, we conduct a comprehensive research study on the topic of radio resource management for relay-based cooperative OFDMA networks supporting heterogeneous QoS requirements. Specifically, this dissertation investigates how to effectively and efficiently allocate resources to satisfy QoS requirements of 4G users, improve spectrum utilization and reduce computational complexity at the base station. The problems and our research achievements are briefly outlined as follows. Firstly, a QoS aware optimal joint relay selection, power allocation and subcarrier assignment scheme for uplink OFDMA system considering heterogeneous services under a total power constraint is proposed. The relay selection, power allocation and subcarrier assignment problem is formulated as a joint optimization problem with the objective of maximizing the system throughput, which is solved by means of a two level dual decomposition and subgradient method. The computational complexity is finally reduced via the introduction of two suboptimal schemes. The performance of the proposed schemes is demonstrated through computer simulations based on OFDMA network. Numerical results show that our schemes support heterogeneous services while guaranteeing each user's QoS requirements with slight total system throughput degradation. Secondly, we investigate the resource allocation problem subject to the satisfaction of user QoS requirements and individual total power constraints of the users and relays. The throughput of each end-to-end link is modeled considering both the direct and relay links. Due to non-convex nature of the original resource allocation problem, the optimal solution is obtained by solving a relaxed problem via two level dual decomposition. Numerical results reveal that the proposed scheme is effective in provisioning QoS of each user's over the conventional resource allocation counterpart under individual total power constraints of the users and relays . Lastly, decentralized resource allocation schemes are proposed to reduce the computational complexity and CSI feedback overhead at the BS. A user centric distributed (UCD) scheme and a relay centric distributed (RCD) scheme are proposed, where the computation of the centralized scheme is distributed among the users and relays, respectively. We also proposed suboptimal schemes based on simplified relay selection. The suboptimal schemes can be combined with the distributed schemes to further reduce of signalling overhead and computational complexity. Numerical results show that our schemes guarantee user's satisfaction with low computational complexity and signalling overhead, leading to preferred candidates for practical implementation. The research results obtained in this dissertation can improve the resource utilization and QoS assurance of the emerging OFDMA networks.

Cognitive radio (CR) is a promising technique to improve spectrum efficiency for wireless communications. This thesis focuses on the resource allocation in two kinds of CR networks (CRNs), traditional CRNs (TCRNs) and cooperative CRNs (CCRNs). In TCRNs, CR sources and destinations communicate directly. By exploring the heterogeneity among CRs, a prioritized CSMA/CA is proposed for demand-matching spectrum allocation. A distributed game is formulated and no-regret learning is adopted to solve the game. Simulation results indicate increase on the number of satisfied CRs. In CCRNs, some nodes are selected as relays to assist the communication. A two-layer auction game is proposed with the first layer performing spectrum allocation and relay formation, and the second layer performing relay allocation. These two layers interact and jointly solve the resource allocation problem. Simulation results show that, compared to counterparts, both the network throughput and convergence time can be improved.

Due to rapid advancements in sensing and computation technology, multiple types of sensors have been embedded in various applications, on-line automatically collecting massive production information. Although this data-rich environment provides great opportunity for more effective process control, it also raises new research challenges on data analysis and decision making due to the complex data structures, such as heterogeneous data dependency, and large-volume and high-dimensional characteristics. This thesis contributes to the area of System Informatics and Control (SIAC) to develop systematic data fusion methodologies for effective quality control and performance improvement in complex systems. These advanced methodologies enable (1) a better handling of the rich data environment communicated by complex engineering systems, (2) a closer monitoring of the system status, and (3) a more accurate forecasting of future trends and behaviors. The research bridges the gaps in methodologies among advanced statistics, engineering domain knowledge and operation research. It also forms close linkage to various application areas such as manufacturing, health care, energy and service systems. This thesis started from investigating the optimal sensor system design and conducting multiple sensor data fusion analysis for process monitoring and diagnosis in different applications. In Chapter 2, we first studied the couplings or interactions between the optimal design of a sensor system in a Bayesian Network and quality management of a manufacturing system, which can improve cost-effectiveness and production yield by considering sensor cost, process change detection speed, and fault diagnosis accuracy in an integrated manner. An algorithm named “Best Allocation Subsets by Intelligent Search” (BASIS) with optimality proof is developed to obtain the optimal sensor allocation design at minimum cost under different user specified detection requirements. Chapter 3 extended this line of research by proposing a novel adaptive sensor allocation framework, which can greatly improve the monitoring and diagnosis capabilities of the previous method. A max-min criterion is developed to manage sensor reallocation and process change detection in an integrated manner. The methodology was tested and validated based on a hot forming process and a cap alignment process. Next in Chapter 4, we proposed a Scalable-Robust-Efficient Adaptive (SERA) sensor allocation strategy for online high-dimensional process monitoring in a general network. A monitoring scheme of using the sum of top-r local detection statistics is developed, which is scalable, effective and robust in detecting a wide range of possible shifts in all directions. This research provides a generic guideline for practitioners on determining (1) the appropriate sensor layout; (2) the “ON” and “OFF” states of different sensors; and (3) which part of the acquired data should be transmitted to and analyzed at the fusion center, when only limited resources are available. To improve the accuracy of remaining lifetime prediction, Chapter 5 proposed a data-level fusion methodology for degradation modeling and prognostics. When multiple sensors are available to measure the degradation mechanism of a same system, it becomes a high dimensional and challenging problem to determine which sensors to use and how to combine them together for better data analysis. To address this issue, we first defined two essential properties if present in a degradation signal, can enhance the effectiveness for prognostics. Then, we proposed a generic data-level fusion algorithm to construct a composite health index to achieve those two identified properties. The methodology was tested using the degradation signals of aircraft gas turbine engine, which demonstrated a much better prognostic result compared to relying solely on the data from an individual sensor. In summary, this thesis is the research drawing attention to the area of data fusion for effective employment of the underlying data gathering capabilities for system modeling, performance assessment and improvement. The fundamental data fusion methodologies are developed and further applied to various applications, which can facilitate resources planning, real-time monitoring, diagnosis and prognostics.

Abstract: Provision of three basic infrastructure services (namely education, health and transport) in Rohtak and Bhiwani Districts (India) is examined using three types of data: 1. 507 households spreading in 8 villages, 2. Informal discussion with villagers and services providers in both districts, and 3. Secondary data for 921 villages and 14 towns and cities. These data were analysed using both statistical and GIS techniques. The analysis reveals that quantitatively there has been considerable expansion of education and health services over a period of fifteen years (1981 to 1996), and the average distance people have to travel to access these services has also declined significantly. But little evidence was found of any logical criterion being followed for the location of new services and the upgrading of existing services. Consequently, there was no improvement in the efficiency level (measured in terms of demand and geographical distance) of existing infrastructure services (both public and private); moreover, the efficiency level of private services was significantly lower than that of public services. It was further observed that the poor and women had relatively poor access to education, health and transport; and income, caste, gender, education level and village location had significant impact on access to and utilisation of basic services. In the study area, public services were functioning sub-optimally and service users were not satisfied with the quality of services; a significant proportion of clients had to rely on private services. Although public services may not be available in all the villages, the main focus should now be on improving the quality of existing services. Therefore, a solid transport network is needed in rural areas so that the availability of frequent and reliable transport services facilitate villagers' access to quality services even if located at distant places. Thus far, the role of the public in service provision has been minimal, which may be one of the reasons for poor quality of public services. Therefore, the active involvement of clients (service users) is essential in the operation, maintenance and monitoring of basic services in order to improve their quality and efficient functioning, and to effectively cater for people's needs in general and deprived sections of the society in particular.

This thesis provides an empirical indication of how the objectives of official development assistance (ODA), granted by the top five donors, affects the aid policy in the MENA region during the period 1990-2012, and how these objectives have changed during the period 2005-2012. As a first result, alleviation of poverty, commercial interests and the democratic status of the recipient altogether influence aid policy in the region. Recipients’ need and commercial interest are both important objectives for the donors but they have both lost some of its impact in recent times. Historical ties with France affect the aid policy in the region and strategic interests of the donors appear to have an unexpected effect on aid allocation behavior e.g. oil rich countries receive less aid, ceteris paribus. The democratic status of the recipient has a positive significant effect on received aid for the average recipient and the impact has increased with time in the MENA region. Moreover, donors react differently to recipients’ needs, commercial interest and democracy and there are also several differences among recipients with abundant oil resources and those with insignificant oil resources.