A New Model for Evaluating the Future Options of Integrating Ground Source Heat Pumps in Building Construction

Decision-making for effective infrastructure integration is challenging because the performances of long-lasting objects often depends on conditions which are either outside the control of the designer or difficult to foresee at the design stage. In this paper we examine a new approach to estimating the range of cost-effective solutions for integrating the construction/retrofit of two or more different types of infrastructure. Infrastructure integration has many perceived benefits, but also faces serious new challenges and doubts from practitioners, particularly in sectors with complex construction process, long asset lives, uncertain cost parameters, and slow and unwieldy decision-making, such as is common with civil engineering works. We test all main options in integrating a ground source heat pump (GSHP) system with the construction and retrofit of an archetypal, office building. A new simulation model is developed and parameterized using actual data in the UK. We incorporate unavoidable uncertainties and randomness in how the decisions are triggered, and test the effectiveness of proactive measures to embed future options. The model highlights how sensitive the range of cost-effective solutions is to the setting of renewable energy incentives, discount rates, technical performance and life-cycle asset management of interdependent infrastructure. This points to a clear need for establishing appropriate regulatory standards. We expect this model to find increasing applications in the planning and designing of integrated complexes of buildings, transport facilities, renewable energy supply, water supply and waste management in dense urban areas, which are an increasingly key part of sustainable urban development

Dichroic atomic vapor laser lock with multi-gigahertz stabilization range

A dichroic atomic vapor laser lock (DAVLL) system exploiting buffer-gas-filled millimeter-scale vapor cells is presented. This system offers similar stability as achievable with conventional DAVLL system using bulk vapor cells, but has several important advantages. In addition to its compactness, it may provide continuous stabilization in a multi-gigahertz range around the optical transition. This range may be controlled either by changing the temperature of the vapor or by application of a buffer gas under an appropriate pressure. In particular, we experimentally demonstrate the ability of the system to lock the laser frequency between two hyperfine components of the $^{85}$Rb ground state or as far as 16 GHz away from the closest optical transition.Comment: 11 pages, 7 figures. Published in Review of Scientific Instruments 201

The health care utility model: a novel approach to doing business

The growth of the Civica Rx health care utility model of addressing shortages of pharmaceutical supplies for hospitals has been gathering momentum since its launch in 2018. The concept is to bypass the major drug makers and to manufacture or subcontract for generic pharmaceuticals that its 1,400-plus member hospitals need. What’s unique about the venture is that it is established as a nonstock, nonprofit 501(c)(4) social welfare organization. The money to run the operation comes from the customers (the hospitals) and philanthropic organizations, not banks or investors in need of a healthy return. The aim is to combine the efficiency of a pro-competitive private enterprise with the equitable mission of a pro–social welfare organization. This new organizational construct represents an opportunity that could be adapted and implemented in other areas of the health care landscape

Gatekeeping, fast and slow: an empirical study of referral errors in the emergency department

Using data from over 300,000 visits to an emergency department (ED), we study the accuracy of gatekeeping decisions - the choices that physicians make regarding patient discharge or admission to the hospital. In our study context, we focus specifically on the effectiveness of a second gatekeeping stage in the ED - a clinical decision unit (CDU). While only 9.9% of patients in our sample are routed through the CDU, we find that had the unit not been in place during the observation period, the rates of unnecessary hospitalization and wrongful patient discharge from the ED would have increased by 14.3% and 29.6%, respectively. We also find that the CDU is especially beneficial for patients with a high ex ante risk of experiencing unnecessary hospitalization, with the rate for the most high-risk patients reduced from 14.0% without the CDU to just 4.8% had all such patients been routed through the CDU. The appropriateness of referrals is therefore a key contributor to the CDU's effectiveness: We estimate that random allocation of patients in our study hospital to the CDU would have reduced the unit's effectiveness by more than half. Finally, we investigate a critical trade-off in designing a two-stage gatekeeping system: Resources must be split between the two stages, increasing congestion in the first stage when the second stage is enlarged. We demonstrate that in the study hospital, the combination of an ED and CDU performs better than a pooled system that combines the capacity of both stages to enlarge the ED but does not have a designated CDU. In fact, we estimate that in this specific case, reducing the size of the first-stage ED in order to expand CDU capacity from the current 9.9% of ED patients to 25% would further reduce unnecessary hospitalizations by up to 33%. We discuss the insights that these results provide as to the circumstances under which it may be advantageous to add a second stage to a gatekeeping system

Separate and concentrate: accounting for patient complexity in general hospitals

Scholars have recently suggested the reorganization of general hospitals into organizationally separate divisions for routine and non-routine services to overcome operational misalignments between the two types of services. We provide empirical evidence for this proposal from a quality perspective, using over 250,000 patient discharge records from 60 German hospitals across 39 high-mortality disease segments, and focusing on in-hospital mortality as outcome. Disentangling the effects of high absolute and relative hospital volumes in a disease group, our analysis suggests that both routine and complex patients would benefit from a hospital organization with a multi-specialty hub for emergency and non-routine elective services at its core, complemented by organizationally separate disease-focused hospitals-within-hospitals for routine services. We also provide evidence that the hub hospital can further improve service quality for complex patients by adopting a disease-based rather than medical specialty-based departmental routing strategy for newly arriving patients. A counterfactual analysis, based on a simultaneous equations probit model that controls simultaneously for endogeneity of volume, focus, and routing strategy, suggests that the proposed reorganization could have reduced mortality in the sample by 13.43% (95% CI [6.87%; 18.95%]) for routine patients and by 11.67% (95% CI [6.13%; 16.86%]) for the most complex patients

Numerical algorithms for dynamic traffic demand estimation between zones in a network

This paper presents numerical methods for dynamic traffic demand estimation between N zones in a network, where the zones are disjoint subsets of nodes of the network. Traffic is assumed to be generated or absorbed only in the zones and nowhere else in the network. Traffic volumes between zones over a fixed period of time are modeled as independent random variables with unknown means which it is desired to estimate. For each zone, the volume of all incoming and outgoing traffic is counted on a regular basis but no information about the origin or destination of the observed traffic is used. Procedures are suggested for a regular update of estimates of the N(N - 1) mean traffic demands between the zones on the basis of an incoming stream of the 2N traffic counts. The procedures are based on an exponential smoothing scheme and are reminiscent of the expectation maximization (EM) algorithm if smoothing is removed. Fast and reliable numerical algorithms, based on the conjugate gradient method, are presented for normal as well as for Poisson traffic demands. The Poisson case is linked with entropy maximization. Computational tests based on simulated data demonstrate both the numerical and statistical efficiency of the procedures.preprin

Economies of scale and scope in hospitals: an empirical study of volume spillovers

General hospitals across the world are becoming larger (i.e. admitting more patients each year) and more complex (i.e. offering a wider range of services to patients with more diverse care needs). Prior work suggests that an increase in patient volume in a hospital service is associated with reduced costs per patient in that service. However, it is unclear how volume changes in one service affect the costs of the other services in the same hospital. This paper investigates such volume-cost spillover effects between elective and emergency admissions and across specialties, using condition-level panel data comprising all acute hospital trusts in England over a period of ten years. We provide evidence that increased elective volume at a hospital is associated with an increase in the cost of emergency care (a negative spillover). Furthermore, for emergency admissions, we find evidence that increased emergency activity in one specialty is associated with lower costs of emergency care in other specialties (a positive spillover). By contrast, we find no evidence of spillover effects across specialties for elective admissions. We discuss the implications of these findings for individual hospital growth strategies and for the regional organization of hospital systems

Empirical research in healthcare operations: past research, present understanding, and future opportunities

We examine the published empirical literature in healthcare operations management over the last 20 years. We note several unique characteristics of the research in healthcare operations, including a focus on operational and organizational variables, an interest in the underlying mechanisms that explain operational causal pathways, and an interest in economic and managerial implications. We organize the prior findings under five distinct themes: importance of operational variables, importance of volume, routing patients through healthcare systems, to err is human, and managing the improvement process. We also identify several key areas of future research, including personalized medicine, value based healthcare, and connected health. We conclude with a call to action for greater engagement with the medical community in areas where tools and insights of operations management can bring about improvements in healthcare delivery

Screening of healthcare workers for tuberculosis: development and validation of a new health economic model to inform practice

Methods for determining cost-effectiveness of different treatments are well established, unlike appraisal of non-drug interventions, including novel diagnostics and biomarkers

Predicting semantic labels of text regions in heterogeneous document images

Contains fulltext : 214639.pdf (publisher's version ) (Open Access)KONVENS 2019: 15th Conference on Natural Language Processing, Erlangen, Germany, October 9-11, 201