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BACKGROUND The Michigan Hand Outcomes Questionnaire is a patient-reported outcome measure that has been validated in many upper extremity disorders using classic test theory. Rasch measurement analysis is a rigorous method of questionnaire validation that offers several advantages over classic test theory and was used to assess the psychometric properties of the Michigan Hand Outcomes Questionnaire. This study used Rasch analysis to evaluate the questionnaire for distal radius fractures in older adults. The incidence and costs of distal radius fractures are rising, and reliable assessment tools are needed to measure outcomes in this growing concern. METHODS Rasch analysis was performed using 6-month assessment data from the Wrist and Radius Injury Surgical Trial. Each domain in the Michigan Hand Outcomes Questionnaire was independently analyzed for threshold ordering, person-item targeting, item fit, differential-item functioning, response dependency, unidimensionality, and internal consistency. RESULTS After collapsing disordered thresholds and removing any misfitting items from the model, five domains (Function, Activities of Daily Living, Work, Pain, and Satisfaction) demonstrated excellent fit to the Rasch model. The Aesthetics domain demonstrated high reliability and internal consistency but had poor fit to the Rasch model. CONCLUSIONS Rasch analysis further supports the reliability and validity of using the Michigan Hand Outcomes Questionnaire to assess hand outcomes in older adults following treatment for distal radius fractures. Results from this study suggest that questionnaire scores should be interpreted in a condition-specific manner, with more emphasis placed on interpreting individual domain scores, rather than the summary Michigan Hand Outcomes Questionnaire score.

In order to maintain a balance between the generation and laod during service restoration, it is important to have mathematical voluminous feeder load measurement data collected duing larg-sclae reotating interruptions is presented in theis paper. REgression voluminous feeder load measurement data collected during large-scale rotating interruptions is presented in this paper. Regression models are proposed to estimate the feeder and substation cold load pickups after scheduled outages.

Scheduling of pumped-storage units at the Taiwan Power Company (TPC) is investigated in this work. In addition to economic considerations, oscillatory stability of the power system as affected by the operation of pumped-storage units is of major concern. To achieve a secure as well as economical dispatching schedule for the pumped-storage units, differential dynamic programming is first employed to reach a preliminary schedule in which total fuel cost of the thermal units over the study period is minimized. Oscillatory stability analysis of the power system under the preliminary schedule is then performed by computing the eigenvalues and eigenvectors for all electromechanical modes. Sensitivities of the eigenvalues for the poorly-damped inter-area mode with respect to individual generator outputs are evaluated. Then a systematic approach based on linear programming is presented to refine the preliminary schedule in order to improve the damping for the inter-area mode. The effectiveness of the proposed approach is demonstrated by short term operational planning of the Taiwan power system.

GaN epitaxial films on (0001) sapphire substrates were fabricated by laser ablation, An ArF excimer laser (193 nm, 25 ns) with an energy of 140 ml/pulse was used for ablating cold-pressed GaN targets made from high-purity GaN powders. Just before the deposition, thermal cleaning of the substrate surface at 1073 K was essential. The substrate temperature was varied between 873 and 1073 K, Above 973 K, the epitaxial layers were obtained, When a buffer layer of GaN was deposited at lower temperatures before the epitaxial growth, the crystalline quality and surface morphology were greatly improved.

The blackout event of July 29, 1999 in Taiwan power system has led to a thorough review of the current Taiwan power service reliability. An in-depth discussion of the incident causes through the analyses of load flow, transient stability (time domain), dynamic stability (frequency domain) and voltage stability is given in this paper. In order to avoid the wide spread incident to occur again, Taiwan Power Company (TPC) has designed and implemented a safety net for preventing extreme contingencies and unplanned events. This paper gives an overview of the safety net, including the design philosophy, action logic and Communication structure.

The accuracy of state estimation determines the usefulness of real-time power system operation and control applications. To have an accurate state estimation it is essential to have the capability of detecting bad measurement data and topology errors in the model. While analogue measurement errors have received considerable attention, relatively little effort has been given to detection of topology errors. A procedure that combines numerical computation and various consistency checks is proposed to detect topology errors in the state estimation model. Tests based on real-time measurement data collected in an energy control centre have indicated that the proposed method can be used to detect branch inclusion, exclusion and bus configuration errors.