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Improving hospital efficiency is a critical concern for health care managers and policy makers. Hospital technical efficiency is measured as the ratio of what quantity and quality of care is produced to what could be produced given the level of resources available to the hospital (its budget). What a hospital should produce given the resources at its disposal is called the “production frontier”. In order to improve hospital performance, health policy makers need knowledge and information about how well the hospitals they fund are utilizing the resources they receive. Data Envelopment Analysis, a non-parametric technique, is applied to administrative data on hospitals in Canada to produce the “technical frontier” and get insight into the variation of technical efficiency of acute hospitals at the Pan-Canadian level (except for the province of Quebec, which does not report its data on hospitals in a way that would make them comparable to the rest of Canada). DEA is preferred to the alternative method of stochastic frontier for the following reasons: DEA does not require to impose a specification on the production function of hospitals (for which theory is clearly lacking), and it allows the analyst to estimate a multi-output frontier (a stochastic frontier would have to weight arbitrarily the value of quantity versus that of quality of care in hospitals, whereas the DEA approach generates these weights from the data). Efficiency scores are serially de-correlated using a bootstrap technique and then entered as the dependent variable in regressions to identify the main factors of efficiency or inefficiency. Specifically, this thesis aims to: 1) estimate the level of technical efficiency of acute inpatient care in 35 teaching hospitals, 54 large hospitals and 90 medium-size hospitals respectively in Canada and identify the potential factors that have influence on technical efficiency; 2) uncover and measure the existence of possible spatial spillovers of hospital efficiency in Canada and examine its potential determinants while taking into account the interaction between hospitals by means of spatial regression; and 3) examine the technical and scale efficiency of the 229 small and rural hospitals across Canada (outside Quebec), as well as estimate the impact of institutional and contextual variables on hospital technical and scale efficiency respectively. The major findings are: 1) hospital output (combination of number and quality of stays; quality being measured as the inverse of in-hospital mortality) in Canada could be increased by 24 percent with the same resources by eliminating inefficiency. Highly efficient teaching hospitals benefit from producing care under favourable environments. Higher efficiency could be achieved by increasing cooperation within the health system and making more post- acute care beds available to both large and medium hospitals; 2) There is a substantial and significantly positive spatial spillover effect on the efficiency of acute inpatient care (elasticity of 0.3): Canadian hospitals are clearly complements to each other and work in networks much more than in competition. The hospital size (the number of beds), the percent of transfers between acute hospitals, and the percent of patient transfers to home care are the main drivers of efficiency among acute hospitals in Canada while controlling of the dependence between hospitals; and 3) Among small hospitals, the average output orientation technical efficiency on all types of services is 54% at the current input-output mix. To improve their technical efficiency, small hospitals should provide with more home care facilities to discharge their patients to (so-called Alternative Level of Care patients) and strengthen their cooperation with larger, urban hospitals. Small hospitals are scale inefficient, specifically, rural hospitals could reduce their size by 34% on average (around 6 acute beds) to achieve the optimal size. The study also found that the spending on diagnosis tests and the nursing as the percentages of total hospital spending (cost shares) are positively and significantly related to the scale efficiency. / Thesis / Doctor of Philosophy (PhD) / A hospital is technically efficient if it uses its resources (its budget) to get the most in terms of quantity (number of stays) and quality of care it can. A hospital can be more or less technically efficient for reasons independent of its control (typically, because of the environment in which the hospital operates) and efficiency is a value-neutral measure. This thesis aims to: 1) estimate the technical efficiency of acute inpatient care in Canada and identify the potential factors that influence the level of efficiency achieved by a given hospital; 2) uncover the existence of possible geographic clusters of efficiency (hospitals that are close geographically are also close in the efficiency scale, something called spatial spillovers in the literature) in Canada.; and 3) examine the role that size plays in the variation of technical efficiency among small and rural hospitals across Canada. The major findings are: 1) hospital output could be increased by 24 percent with the same resources by eliminating technical inefficiency; 2) There is a substantial and significantly positive spatial spillover effect on the efficiency of acute inpatient care: being close to an efficient hospital increases the efficiency score of a hospital, everything else being the same; and 3) The level of technical efficiency of small and rural hospitals across Canada is low overall and, perhaps surprisingly, larger rural hospitals are among the least efficient: among small hospitals, scale does not yield economies of resources.

A group of 35 loggers located across the southeastern United States provided 192 logger years of productivity and cost information. Information, including logger demographics, business, and operational data, was also collected through an interview process with the participants. Indicators of the overall economic health of the southeastern U.S. logging industry was determined by measuring technical efficiency, and by analyzing the demographic, organizational, business, productivity and cost information with a variety of quality control tools. Data Envelopment Analysis, a non-parametric statistical tool, was used to measure the technical efficiency associated with each logger year. Demographic information, including age, experience, and education, appeared to have only minimal impacts on contractor efficiency, indicating that business, operational, and environmental factors have greater influence on efficiency. Groups of observations with low proportions of total cost relating to equipment and consumables tended to have the highest median efficiency scores. Observations with lower median efficiency tended to have higher proportions of their costs associated with equipment and/or consumables. These trends indicate that efficiency, or operating in the area of least costs, is not necessarily in the best interest of the logging contractors or the wood supply system as a whole. These contractors are not in the process of building equity, which is important in order to maintain a productive supplier force. There was an upward trend in yearly production and costs during the period. Production and cost levels generally increased from 1990 through 1995, before dropping off in 1996. Yearly efficiency was cyclical, but appeared to be in a general state of decline for the period. The Wilcoxon signed rank test ruled that 1996 was statistically lower than the previous 6 years at the 90% confidence level. The efficiency decline was due in part to the inability of productivity increases to keep pace with inflation throughout the 1990's, influence of fixed costs, and the period of pulp an paper market oversupply in the mid 1990's. The relationship between efficiency and profitability was examined using marginal cost and revenue analysis. Profits were not collected as part of this study, therefore an arbitrary rate of $12 per ton was assumed. These analyses served to point out the approximate scale size associated with maximum efficiency and revenue. Efficiency is an important prerequisite of profitability, but when green tons of wood is considered the output of the process, the point of maximum efficiency is not always where efficiency is maximized. / Master of Science

Planning is the act of determining the steps necessary for an organization to obtain goals in the future. Planning takes on even more importance as competition increases and additional efficiency is needed. In today's competitive business environment, any method that can be utilized to maintain an advantage over an organization's competitors must be investigated. Organizations allocate time and resources dedicated to planning differently. Differences are directly related to the goal that is being planned for and the amount of time before the goal is to be met. This study was undertaken to determine what levels of planning and communication were present in the wood supply industry and to determine how information that was being exchanged was being used in these processes. During 2001, Virginia Tech Forestry Operations researchers completed a study to assess the current state of planning and communication in the industrial wood supply process and to identify opportunities for improvement. Researchers performed interviews with 169 individuals representing all segments of the wood supply system. Interviews were performed during the summer of 2001 in the southeast and northeast regions of the United States. The overall findings of this study showed that current planning in the wood supply system is primarily "reactive" rather than proactive, resulting in extremely short planning horizons for all segments of the wood supply chain. This is due in some part to the high degree of uncertainty facing the forest and logging industries in today's business climate, but is also a result of a continuation of traditional business practices that promote inefficiencies in the wood supply chain. Frequent, short term changes in mill requirements, including delivery schedules, inventories, and specifications, drive many of the constraints to planning in the wood supply system. Thirty-five percent of the wood procurement organizations interviewed reported that the consumption mix at their mill often changed on a weekly basis, and 65% reported they typically receive only one or two week's notice in advance of significant changes in mill wood requirements. Advances in communication technology, such as cell phones, are facilitating frequent verbal communications between all segments of the wood supply chain. These communication improvements are also a factor in reducing the planning horizons for suppliers. As consumers adopt and use these communications technologies they are being used to actively manage daily (rather than weekly, monthly) wood flows as "just-in-time" inventory management goals. While 60% of the loggers interviewed reported they communicated at least twice a week or more with their wood dealer or procurement forester, 70% reported that these communications were only "somewhat" or "not helpful" in planning their production goals. More than 75% of the contract loggers interviewed know the location and characteristics of the next tract they will harvest less than one week before they move their equipment and begin harvesting operations. This common and wide-spread industry practice of delaying critical information to loggers with regard to tract allocation creates a barrier to effective operational harvest planning, and provides one of the greatest opportunities for substantial cost savings through improved planning and communications. Compensation rates for logging contractors are primarily determined (70%) through the application of consumer's logging cost models or dealer's "market" rates which facilitate little if any true negotiation for harvesting system cost items. These models are generally based on projected "average" production rates that do not reflect consumer-imposed constraints such as quota reductions, additional mandated moves, or tract allocation "mismatches". Efficient and predictable wood flow is critical to a stable and profitable forest and logging industry. Mill management and wood procurement personnel should plan their wood requirements, inventory and delivery schedules on an annual basis and effectively communicate these plans to the appropriate suppliers to facilitate their (suppliers') ability to conduct meaningful long-term strategic and tactical planning. Without adequate planning all participants of a system lose control and generate inefficiency. Proper planning reduces the likelihood that obstacles will dramatically affect the efficiency and corresponding productivity of these participants. The results are improved productivity and increased return on capital employed. / Master of Science

ITC/USA 2007 Conference Proceedings / The Forty-Third Annual International Telemetering Conference and Technical Exhibition / October 22-25, 2007 / Riviera Hotel & Convention Center, Las Vegas, Nevada / Shaped Offset Quadrature Shift Keying (SOQPSK) is a spectrally efficient modulation that has been promoted in the airborne telemetry community as a more spectrally efficient alternative for legacy PCM/FM. First generation demodulators for SOQPSK use coherent detectors which achieve good bit error rates at the expense of long synchronization times. This paper examines the performance of a noncoherent SOQPSK detector which significantly improves the signal acquisition times without impacting BER performance in the AWGN environment. The two detection methods are also compared in their ability to combat other channel impairments, such as adjacent and on-channel interference.

The widespread application of wireless services and the requirements of ubiquitous access have recently triggered rapidly booming energy consumption in wireless communications networks. Such escalation of energy consumption in wireless networks causes high operational expenditure from electricity bills for operators, unsatisfactory user experience due to limited battery capacity of wireless devices, and a large amount of greenhouse gas emission. Green radio (GR), which emphasizes both energy efficiency (EE) and spectral efficiency (SE), has been proposed as an effective solution and is becoming the mainstream for future wireless network design. Unfortunately, EE and SE do not always coincide and may even sometimes conflict. In this dissertation, we focus on energy-efficient transmission and resource allocation techniques for orthogonal frequency division multiple access (OFDMA) networks and the joint energy-efficient design of OFDMA and other promising wireless communications techniques, such as cognitive radio (CR) and two-way relay. Firstly, we investigate the principles of energy-efficient design for pure OFDMA networks. As the first step, we study the fundamental interrelationship between EE and SE in downlink OFDMA networks and analyze the impacts of channel gain and circuit power on the EE-SE relationship. We establish a general EE-SE optimization framework, where the overall EE, SE and per-user quality-of-service (QoS) are all considered. Under this framework, we find that EE is quasiconcave in SE and decreases with SE when SE is large enough. These findings are very helpful guidelines for designing energy- and spectral-efficient OFDMA. To facilitate the application of energy-efficient resource allocation, we then investigate the energy-efficient resource allocation in both downlink and uplink OFDMA networks. For the downlink transmission, the generalized EE is maximized while for the uplink case the minimum individual EE is maximized, both under prescribed per-user minimum data rate requirements. For both transmission scenarios, we first provide the optimal solution and then develop an computationally efficient suboptimal approach by exploring the inherent structure and property of the energy-efficient design. Then we study energy-efficient design in downlink OFDMA networks with effective capacity-based delay provisioning for delay-sensitive traffic. By integrating information theory with the concept of effective capacity, we formulate and solve an EE optimization problem with statistical delay provisioning. We also analyze the tradeoff between EE and delay, the relationship between spectral-efficient and energy-efficient designs, and the impact of system parameters, including circuit power and delay exponents, on the overall performance. Secondly, we consider joint energy-efficient design of OFDMA and CR and two-way relay, respectively, to further enhance the EE and SE of wireless networks. We study energy-efficient opportunistic spectrum access strategies for an OFDMA-based CR network with multiple secondary users (SUs). Both worst EE and average EE of the SUs are considered and optimized subject to constraints including maximum transmit power and maximum interference to primary user (PU) system. For both cases, we first find the optimal solution and then propose a low-complexity suboptimal alternative. The results show that the energy-efficient CR strategies significantly boost EE compared with the conventional spectral-efficient CR ones while the low-complexity suboptimal approaches can well balance the performance and complexity. Then we study energy-efficient resource allocation for OFDMA-based two-way relay, which aims at maximizing the aggregated EE utility while provisioning proportional fairness in EE among different terminal pairs. Different from most exist energy-efficient design, we consider a new circuit power model, where the dynamic circuit power is proportional to the number of active subcarrier. For low-complexity solution, we propose an EE-oriented sequential subchannel assignment policy and discover the sufficient condition for early termination of the sequential subchannel assignment without losing the EE optimality. It is found that the energy-efficient transmission does not necessarily make all the subcarriers active, which is another useful principle for practical energy-efficient system design.

International Telemetering Conference Proceedings / October 27-30, 1997 / Riviera Hotel and Convention Center, Las Vegas, Nevada / A simple, low cost radio frequency (RF) power and spectrally efficient integrated transceiver/modem architecture employing Feher’s patented Quadrature Phase Shift Keying (FQPSK) is described. The FQPSK signals presented in this paper are obtained by using additional post low-pass filters in the FQPSK architecture. This implementation significantly improves the spectral efficiency of the worldwide commercially standardized Gaussian Minimum Shift Keying (GMSK) systems. The Bit Error Rate (BER) performance of FQPSK in additive white Gaussian noise (AWGN) channel has been investigated by means of computer simulation and hardware prototype measurements. The results of the hardware and software simulations are compared to GMSK and QPSK/OQPSK performance. These results show that the filtered FQPSK modulated signal passing through a non-linear amplifier (NLA) can achieve a spectral efficiency improvement of about 60% over NLA filtered OQPSK and an integrated spectral efficiency improvement of 50% over GMSK and a better BER performance. In particular, 100 kb/s to 34 Mb/s hardware experimental results over 2.4 GHz NLA (saturated) 1 Watt system confirmed that FQPSK hardware systems attain a BER=f(Eb/N0) performance within 1 dB to 2 dB of predicted theoretical results.

Doctor of Philosophy / Department of Agricultural Economics / Michael Langemeier / This study focused on the inclusion of risk in efficiency measures to determine its impact on traditional efficiency scores. Previous research and theory suggests efficiency scores will be lower under risk and for risk averse individuals. Risk aversion may deter use of new production technologies and production levels may not be as high as under other risk preferences. Two data sets were used in the analysis. A panel data set of 256 farms from 1993-2010 was used to address the impact of risk measured as variability in outputs and downside risk on efficiency. A separate data set of 258 farms for 2008 was used with a corresponding risk preference score to determine the impact of risk preference on efficiency. The risk preference scores in the sample ranged from 5 to 86 where a smaller value represents stronger risk aversion. Data envelopment analysis was used to construct a nonparametric efficiency frontier and calculate cost- and revenue-based economic, overall, technical, allocative, and scale efficiency measures. Five inputs: labor, crop input, fuel, livestock input, and capital; and two outputs: crops and livestock were used in the analysis. The results focused on cost- and revenue-based economic efficiency. They showed that risk did affect average efficiency scores and is necessary to include in efficiency analysis. The average cost efficiency without risk was 0.6763. It increased to 0.7200 and 0.7018 respectively when cost efficiency was adjusted to recognize variability in outputs and downside risk. The average portion of cost inefficiency explained by variability in outputs was 28.06 percent. Downside risk explained 22.66 percent of cost inefficiency. The average revenue efficiency without risk was 0.7611 and increased to 0.8372 and 0.7811 when revenue efficiency was adjusted for variability in outputs and downside risk, respectively. Variability in outputs explained 42.53 percent and downside risk explained 30.58 percent of revenue inefficiency. The average cost efficiency for the 258 farms was 0.5691 and increased to 0.6043 with the consideration of risk preference scores. The average revenue efficiency was 0.6735 and increased to 0.6987 with risk preference scores. The efficient farms varied across cost and revenue efficiency, and the risk measures used. This lends support to the use of both input-oriented (cost) and output-oriented (revenue) efficiency measures as well as the use of multiple measures of risk.