Feasibility study of an optical radiometer for determining the composition of the Mars atmosphere from shock layer radiation during entry, volume II Final report

Optical radiometer feasibility study for determining composition of Mars atmosphere from shock layer radiation during entry - instrumentatio

Hospital Reimbursement in the Presence of Cherry Picking and Upcoding

Hospitals throughout the developed world are reimbursed on the basis of diagnosis-related groups (DRGs). Under this scheme, patients are divided into clinically meaningful groups, and hospitals receive a fixed fee per patient episode tied to the patient DRG. The fee is based on the average cost of providing care to patients who belong to the same DRG across all hospitals. This scheme, sometimes referred to as ‘yardstick competition’, provides incentives for cost reduction, as no hospital wants to operate at a higher cost than average, and can be implemented using accounting data alone. Nevertheless, if costs within a DRG are heterogeneous, this scheme may give rise to cherry-picking incentives, where providers ‘drop’ patients who are more expensive to treat than average. To address this problem, regulators have tried to reduce within DRG cost heterogeneity by expanding the number of DRG classes. In this paper, we show that even if cost heterogeneity is eliminated, such expansion will fail to completely eliminate patient cherry picking. In equilibrium, the market will bifurcate into two groups, one of which will continue to cherry-pick patients and underinvest in cost reduction, while the other group treats all patients. Furthermore, we show that DRG expansion is particularly problematic if hospitals are also able to ‘upcode’ patients, i.e., intentionally assign patients to a more resource-intensive DRG than needed to increase income. Upcoding increases within DRG cost heterogeneity and amplifies cherry-picking incentives. We examine potential solutions involving yardstick competition based on input statistics

Impact of Arrivals on Departure Taxi Operations at Airports

Aircraft taxi operations are a major source of fuel burn and emissions on the ground. Given rising fuel prices and growing concerns about the contributions of aviation to air pollution and greenhouse gas emissions, recent research aims to develop strategies to reduce fuel burn at airports. In order to develop such strategies, an understanding of taxi operations and the factors that affect taxi-out times is required. This paper describes an analysis of taxi-out times at two major U.S. airports in order to identify the primary causal factors affecting the duration of taxi-out operations. Through an analysis of departures out of John F. Kennedy International Airport and Boston Logan International Airport, several variables affecting taxi-out times were identified, including primarily the number of arrivals and number of departures during the taxi-out operation of an aircraft. Previous literature suggests that the number of arrivals on the surface has limited influence on taxi-out times; however, this analysis demonstrates that the number of arrivals is in fact significantly correlated with taxi-out times. Furthermore, we find that arrivals have a greater impact on taxi-out times under runway configurations where there is increased interaction between arrivals and departures

Обоснование конструктивных параметров горизонтального роторного агрегата для дробления фуражного зерна

A horizontal impact crusher provides for high­quality grinding of grain materials and getting the finished product equalized by particle size distribution to 98 percent. The effectiveness of the crusher is determined by the following parameters: rotor speed, operating clearance, intensity and full filling of the crushing chamber, the duration of impact on the original product, the design features of the working bodies and the geometric design of their corrugated surfaces. (Research purpose) To determine the design parameters of a horizontal rotary crusher for feed grains. (Materials and methods) The influence of the stator flute number on the quality of the crushed product has been studied by three indicators: the grinding degree, the grinding module, the actual effectiveness of the grinding process. It has been found that as the flute number increases, the grinding module and the degree of grinding change insignificantly, and the actual effectiveness of grinding decreases. In this case, the finished product corresponds to coarse grinding. A comparative experiment has been conducted with two design variants of the working surfaces with one stator contradiction to check the effectiveness of changing the shape of the rotor and stator flutes. (Results and discussion) It has been determined that the geometrical parameters of flute working elements of a horizontal rotary crusher can be calculated using the proposed model of theoretical calculation based on the type of material crushed and zootechnic requirements. An angular shape of the rotor grooves also has a positive effect on the overall performance of the grinding process. (Conclusions) The authors present theoretical substantiation of the design features of cutting flute working surfaces of a horizontal rotary crusher and the calculation of the rotor diameter. They have proposed a model for calculating these parameters basing on the type of crushed grain crops. They have experimentally compared various design forms and the number of stator contradictions with respect to the quality of the products obtained. The main manufacturing parameters of rotor grooves have been calculated for the most common grain crops (wheat, barley, oats, and corn) and their optimal values have been theoretically substantiated.Горизонтальная роторная дробилка позволяет качественно измельчать зерновые материалы и получать готовый продукт, выравненный по гранулометрическому составу до 98 процентов. Эффективность работы дробилки определяют следующие параметры: частота вращения ротора, рабочий зазор, интенсивность и плотность заполнения дробильной камеры, длительность воздействия на исходный продукт, конструктивные особенности рабочих органов и геометрическое исполнение их рифленых поверхностей. (Цель исследования) Обосновать конструктивные параметры горизонтальной роторной дробилки фуражного зерна. (Материалы и методы) Исследовали влияние количества рифлей статора на качество измельченного продукта по трем показателям: степень измельчения, модуль помола, фактическая результативность процесса измельчения. Выявили, что при увеличении количества рифлей модуль помола и степень измельчения меняются незначительно, а фактическая результативность измельчения снижается. При этом готовый продукт соответствует грубому помолу. Провели сравнительный эксперимент двух конструктивных вариантов исполнения рабочих поверхностей при одном противорезе статора для проверки эффективности изменения формы рифлей ротора и статора. (Результаты и обсуждение) Определили, что геометрические параметры рифлей рабочих органов горизонтальной роторной дробилки можно вычислить, используя предложенную модель теоретического расчета, исходя из вида измельчаемого материала и зоотехнических требований. Придание угловой формы пазам ротора также оказывает положительное влияние на общие показатели процесса измельчения. (Выводы) Представили теоретическое обоснование конструктивных особенностей нарезки рифлей рабочих поверхностей горизонтальной роторной дробилки и расчет диаметра ротора. Предложили модель определения этих параметров исходя из вида измельчаемой зерновой культуры. Провели экспериментальное сравнение различных форм исполнения и количества противорезов статора относительно качества получаемой продукции. Основные параметры изготовления пазов ротора рассчитали для наиболее распространенных зерновых культур (пшеница, ячмень, овес, кукуруза) и теоретически обосновали их оптимальные значения

Health Industries in the Twentieth Century. Introduction

This article is the introduction to the special issue' Health Industries in the Twentieth Century'. It offers a broad literature review of scholarly works about the history of health and medicine, and stresses the opportunities for business historians to tackle the field of healthcare

The future for follow-up of gynaecological cancer in Europe. Summary of available data and overview of ongoing trials

After completing treatment, most patients follow a pre-determined schedule of regular hospital outpatient appointments, which includes clinical examinations, consultations and routine tests. After several years of surveillance, patients are transferred back to primary care. However, there is limited evidence to support the effectiveness and efficiency of this approach. This paper examines the current rationale and evidence base for hospital-based follow-up after treatment for gynaecological cancer. We investigate what alternative models of care have been formally evaluated and what research is currently in progress in Europe, in order to make tentative recommendations for a model of follow-up. The evidence base for traditional hospital based follow-up is limited. Alternative models have been reported for other cancer types but there are few evaluations of alternative approaches for gynaecological cancers. We identified five ongoing European studies; four were focused on endometrial cancer patients and one feasibility study included all gynaecological cancers. Only one study had reached the reporting stage. Alternative models included nurse-led telephone follow-up and comparisons of more intensive versus less intensive regimes. Outcomes included survival, quality of life, psychological morbidity, patient satisfaction and cost effectiveness of service. More work is needed on alternative strategies for all gynaecological cancer types. New models will be likely to include risk stratification with early discharge from secondary care for early stage disease with fast track access to specialist services for suspected cancer recurrence or other problems

Managing the outsourcing of two-level service processes: Literature review and integration

The outsourcing of service processes presents several complex management challenges. Services typically have variability in both the pattern of customer arrivals and service times, which make capacity planning challenging. Workers also have discretion over the workflow, and therefore each worker can affect the workload passed to other parts of the system. When a service process is outsourced, this discretion may be in the hands of a vendor who then makes choices that influence the customer experience. A firm must decide upon the design of the process, which parts of the process to outsource, and how to contract with the vendor to overcome issues related to information asymmetry. This paper addresses these questions within the context of a two-level service process where the first level serves as a gatekeeper for experts in the second level. We integrate the results from several papers in the literature to give a comprehensive perspective on how to approach service outsourcing. © 2010 IEEE.link_to_subscribed_fulltex