Discharge Scheme Research Articles

Charge structure of a summer thunderstorm in North China: Simulation using a Regional Atmospheric Model System

Electrification and simple discharge schemes are coupled into a 3D Regional Atmospheric Model System (RAMS) as microphysical parameterizations, in accordance with electrical experiment results. The dynamics, microphysics, and electrification components are fully integrated into the RAMS model, and the inductive and non-inductive electrification mechanisms are considered in the charging process. The results indicate that the thunderstorm mainly had a normal tripole charge structure. The simulated charge structure and lightning frequency are basically consistent with observations of the lightning radiation source distribution. The non-inductive charging mechanism contributed to the electrification during the whole lifetime of the thunderstorm, while the inductive electrification mechanism played a significant role in the development period and the mature stage when the electric field reached a large value. The charge structure in the convective region and the rearward region are analyzed, showing that the charge density in the convective region was double that in the rearward region.

Simulation of the electrification of a tropical cyclone using the WRF-ARW model: An idealized case

Evolution of the electrification of an idealized tropical cyclone (TC) is simulated by using the Advanced Weather Research and Forecasting (WRF-ARW) model. The model was modified by addition of explicit electrification and a new bulk discharge scheme. The characteristics of TC lightning is further examined by analyses of the electrification and the charge structure of the TC. The findings thus obtained are able to unify most of the previous inconsisitent observational and simulation studies. The results indicate that the TC eyewall generally exhibits an inverted dipole charge structure with negative charge above the positive. In the intensification stage, however, the extremely tall towers of the eyewall may exhibit a normal tripole structure with a main negative region between two regions of positive charge. The outer spiral rainband cells display a simple normal dipole structure during all the stages. It is further found that the differences in the charge structure are associated with different updrafts and particle distributions. Weak updrafts, together with a coexistence region of different particles at lower levels in the eyewall, result in charging processes that occur mainly in the positive graupel charging zone (PGCZ). In the intensification stage, the occurrence of charging processes in both positive and negative graupel charging zones is associated with strong updraft in the extremely tall towers. In addition, the coexistence region of graupel and ice crystals is mainly situated at upper levels in the outer rainband, so the charging processes mainly occur in the negative graupel charging zone (NGCZ).

Feasibility study for early supported discharge in adults with respiratory infection in the UK

BackgroundMany patients with pneumonia and lower respiratory tract infection that could be treated as outpatients according to their clinical severity score, are in fact admitted to hospital. We investigated whether, with medical and social input, these patients could be discharged early and treated at home.Objectives: (1) To assess the feasibility of providing an early supported discharge scheme for patients with pneumonia and lower respiratory tract infection (2) To assess the patient acceptability of a study comprising of randomisation to standard hospital care or early supported discharge scheme.MethodsDesign: Randomised controlled trial.Setting: Liverpool, UK. Two University Teaching hospitals; one city-centre, 1 suburban in Liverpool, a city with high deprivation scores and unemployment rates.Participants: 200 patients screened: 14 community-dwelling patients requiring an acute hospital stay for pneumonia or lower respiratory tract infection were recruited.Intervention: Early supported discharge scheme to provide specialist respiratory care in a patient’s own home as a substitute to acute hospital care.Main outcome measures: Primary - patient acceptability. Secondary – safety/mortality, length of hospital stay, readmission, patient/carer (or next of kin) satisfaction, functional status and symptom improvement.Results42 of the 200 patients screened were eligible for early supported discharge; 10 were only identified at the point of discharge, 18 declined participation and 14 were randomised to either early supported discharge or standard hospital care. The total hospital length of hospital stay was 8.33 (1–31) days in standard hospital care and 3.4 (1–7) days in the early supported discharge scheme arm. In the early supported discharge scheme arm patient carers reported higher satisfaction with care and there were less readmissions and hospital-acquired infections.Limitations: A small study in a single city. This was a feasibility study and therefore not intended to compare outcome data.ConclusionsAn early supported discharge scheme for patients with pneumonia and lower respiratory tract infection was feasible. Larger numbers of patients would be eligible if future work included patients with dementia and those residing in care homes.Trial registrationISRCTN25542492.

Cambridgeshire cataract shared care model: community optometrist-delivered postoperative discharge scheme

Background/aimsTo evaluate a community optometrist-delivered postoperative discharge scheme in patients who underwent same day discharge from the hospital eye service (HES) following cataract surgery.MethodsA service-level agreement (SLA) was agreed between...

P137 Internal validation of the DECAF score as a predictor of inpatient mortality in acute exacerbations of COPD

IntroductionIn patients presenting with an acute exacerbation of COPD (AECOPD), accurate prediction of in-hospital mortality may help inform the most appropriate place and level of care. The DECAF score was...

Study on the Characteristics of Different Plasma Ignition Schemes

Plasma ignition mechanisms have always been the central issue in the electrothermal-chemical (ETC) launch technology. Generally, there are two types of ignition schemes, namely, the axial discharge scheme and the radial discharge scheme, and the two schemes are supposed to have different ignition characteristics. This work is devoted to study the features of different plasma ignition schemes in the ETC launch devices. A capillary discharge setup and a gap discharge setup are utilized in the experiments to represent the axial and radial discharge ignition schemes, respectively, and three types of propellants are used in the study. Using the measured data in the experiments, plasma heat fluxes are solved by a plasma-propellant interaction model. In addition, the propellant surface conditions are investigated by a scanning electron microscope after the plasma ignition experiments. The surface conditions of propellants in different ignition schemes display distinct features, which are analyzed to shed light on the characteristics of different ignition schemes and the responses of different propellants. Results are supposed to help in interpreting the plasma-propellant interaction mechanisms in different ignition schemes and provide references for the optimization design of plasma ignition installations in the ETC launch devices.

Resolving Trans-jurisdictional Water Conflicts by the Nash Bargaining Method: A Case Study in Zhangweinan Canal Basin in North China

Trans-jurisdictional conflict in both water quantity and quality is a general concern in large river basins. In this paper, the relative utility function combined with the asymmetric Nash bargaining method was established to analyze the trans-jurisdictional conflict between water quantity and water quality in the Zhangweinan Canal Basin in China. The basin was divided into four conflict stakeholders, namely, Shanxi, Hebei, Henan, and Shandong Provinces, based on administrative unit. The water usage and pollutant discharge scheme for multiple stakeholders was optimized using the established model to satisfy the environmental flow and water quality objectives at the identified conflict sections. The results indicated that the total water consumption was reduced from 4.38 × 109 m3 in 2007 to 1.97 × 109 m3, and that the allowable COD and NH3-N discharged into the river was less than 3.8 × 104 t and 4.3 × 103 t, respectively. About 81.1 % of COD and 76.1 % of NH3-N should be further reduced compared with the values in 2007.

Study on nutrient distribution and interaction with sediments in a macro-tidal estuary

An integrated hydro-environmental model has been developed for predicting the distribution of nutrients in estuarine and coastal waters. This paper also reports on an application of the model to the Loughor Estuary in the UK, which has a high tidal range. The horizontal two-dimensional model considers the hydrodynamic, sediment transport, dissolved oxygen and nutrient cycling processes. In particular, the effect of sediment suspension and deposition on the nutrient distribution in the water column has been included in the model. A TVD-MacCormack scheme has been adopted to numerically solve the coupled partial differential equations. Field surveys and laboratory experiments in connection with the Loughor Estuary were conducted to obtain measured data for model calibration and verification. It was found that the linear isotherm model gave a good approximation of the adsorption/desorption processes over the range of nitrogen and phosphorus concentrations measured in the natural estuary. Through experiments on the collected soil samples, the salinity-dependent partition ratios between the adsorbed and dissolved nutrients were determined. The results of the established model showed good agreement with the measured data. Finally, the model was used to examine the implications of changing the sewage effluent discharge scheme on the nutrient distributions in the estuary.

P283 Relationship Between the Ranking of COPD Outcome Measures (Re-Admissions and Emergency Bed Days) and Respiratory Service Provision Across the 13 PCTs in the East of England (EOE)

The White Paper “Equity and Excellence. Liberating the NHS” stated that the health service must be focused on two key parameters i) outcomes and ii) the quality standards that deliver...

The Charge and Discharge Scheme of the Battery in the Solar Lighting System

This article gives the description of the scheme of solar lighting control system. Solar energy is accepted commonly as a green energy because of its unique advantages. In the strong support of the government, the Photovoltaic (PV) generation system gains a rapid development. The stand-alone and grid-connected PV generation systems will be the trend among PV applications. Based on the solar lighting control system, the scheme includes using intelligent control to complete charging and discharging to prevent the battery from being over-charged and over-discharged. Meanwhile the constant current technology is used to drive LED, and the integrated circuit technology is used to implement the solar energy lighting optically controlled self extinguishing.

Packaging and testing of a hydrogen safety sensor prototype

In this article, testing of an electrochemical, potentiometric hydrogen safety sensor is reported within a proposed packaging scheme. Device packaging under static and flow testing conditions are presented. During the static volume sensor testing, the sensors response is compared against a calibrated Gas Chromatography (GC) measurement. Also, a commercial H2 sensor is incorporated into the test chamber to act as a benchmark for the sensor prototype. In the testing phase, H2 selectivity is demonstrated using pulsed discharge technique.The packaging schemes for static and flow condition testing permit easy handling and exchange of the laboratory prototype sensors with other agencies for independent testing/performance validation. Upon testing, for a fixed inlet concentration of 2% (20,000 ppm) H2 and within the duration of the typical experiment conducted within a non-sealed test chamber, the sensor sees only around 6200 ppm as confirmed by the GC measurements. The sensitivity is around 105 mV for 6200 ppm of H2. While a logarithmic correlation of the sensor output with H2 concentration is observed in laboratory based H2 sensor, the commercial device suffered from an elevated baseline (due to reduced barometric pressure conditions of 2195 m elevation), humidity and uncorrelated sensor output for different H2 concentrations. The pulsed discharge scheme for achieving hydrogen selectivity holds a great potential for tackling cross-sensitivity problems that affect many H2 sensor technologies.

Early Supported Discharge after Stroke in Bergen (ESD Stroke Bergen): A Randomized Controlled Trial Comparing Rehabilitation in a Day Unit or in the Patients' Homes with Conventional Treatment

As a result of demographic changes with a presumed rapidly increasing number of older people during the coming decades, a strong increase in the incidence and prevalence of stroke should be expected. Early supported discharge implies that the patients are discharged to their homes as soon as feasible and that rehabilitative treatment is offered after the discharge, with the patients being home-dwelling. This has proved beneficial in previous studies. The main objective of this study is to further characterize the important components of early supported discharge and to confirm superiority of early supported discharge over conventional treatment. The secondary aim will be to compare two different early supported discharge schemes. These early supported discharge schemes are composed of intensive rehabilitation treatment given by a multidisciplinary team in a day unit and, alternatively, the same treatment given in the patients' homes. The study is conducted as a randomized controlled trial with three arms: two different forms of early supported discharge and a control arm with conventional treatment. Patients with acute stroke admitted to our hospital's stroke unit and living in the Municipality of Bergen are considered for inclusion. A total of 350 stroke patients are expected. Primary outcome is modified Rankin Scale six-months after inclusion. Secondary outcomes include Barthel Index and National Institute of Health Stroke Scale at several points in time after inclusion, as well as many other schemes, questionnaires and physical tests. The study is registered in ClinicalTrials.gov registration number NCT00771771.

Flow Classification of Negatively Buoyant Surface Discharge in an Ambient Current

Abstract Surface discharge of negatively buoyant effluents into moving waterbodies creates a range of complex flow behavior. These complexities in the hydrodynamic phenomena develop through the interplay between a discharge's initial fluxes and the motion of the ambient current, which advects the discharge fluid downstream. In the present study, experiments were conducted for a comprehensive range of initial fluxes for negatively buoyant discharges in an ocean current through rectangular and semicircular channels. From this data, three flow regimes—the free surface jet, the shore-attached surface jet, and the plunging plume—and their range of occurrences were identified. These observations provide the basis for developing a revised flow classification diagram, which differs significantly from the positively buoyant discharge scheme as expected. A major difference is in the transition from the free surface jet regime to the shore-attached surface jet, whereas the plume-like regime has the same transition c...

S65 Early supported discharge scheme (ESDS) for pneumonia & lower respiratory tract infection (LRTI): are there enough suitable patients?

BackgroundDespite the fact that ∼75% of community acquired pneumonia (CAP) is managed in the community, admissions for pneumonia, influenza & LRTI account for more than 2.3 million bed days/yr in...

Analysis of alternate discharge schemes for arterial crude-oil pumps based on numerical solution of hydrodynamics equations

Numerical calculations are performed for various alternate discharge schemes for an arterial crude-oil pump with an interchangeable flow-through spiral casing. Possible design solutions are analyzed for an increase in pump efficiency in cases of necessity.

Changes in NHS organization of care and management of hospital admissions with COPD exacerbations between the national COPD audits of 2003 and 2008

The 2003 UK Chronic Obstructive Pulmonary Disease (COPD) audit revealed wide variability between hospital units in care delivered. To assess whether processes of care, patient outcomes and organization of care have improved since 2003. A UK national audit was performed in 2008 to survey the organization and delivery of clinical care provided to patients admitted to hospital with COPD. All UK acute hospital Trusts (units) were invited to participate. Each unit completed cross-sectional resource and organization questionnaires and a prospective clinical audit comprising up to 60 consecutively admitted cases of COPD exacerbation. Comparison between 2003 and 2008 includes aggregated statistics for units participating in both audit rounds. A total of 192 units participated in both audit rounds (6197 admissions in 2003 and 8170 in 2008). In 2008, patients were older and of a poorer functional class. Overall mortality was unchanged but adjusting for age and performance status, inpatient mortality (P = 0.05) and 90-day mortality (P = 0.001) were both reduced in 2008. More patients were discharged under a respiratory specialist (P < 0.01), treated with non-invasive ventilation if acidotic (P < 0.001) and accepted onto early discharge schemes (P < 0.01) while median length of stay fell from 6 to 5 days (P < 0.001). Within these mean data, however, there remains considerable inter-unit variation in organization, resources and outcomes. Overall improvements in resources and organization are accompanied by reduced mortality, shorter admissions and greater access to specialist services. There remains, however, considerable variation in the quality of secondary care provided between units.

Optimisation design for EEPROM embedded in UHF-RFID passive transponders

Low cost and low power are the major requirements for radio-frequency identification (RFID) applications. In this article, optimisation techniques on ultra-high frequency (UHF) RFID passive transponders are proposed to achieve low power without loss of area. The optimisations cover the key sub-circuits, such as the charge pump, discharge scheme and sense amplifier in the embedded electrically erasable programmable read-only memory (EEPROM) of UHF RFID-passive transponders. A 256-byte EEPROM for UHF RFID application with an 0.8 mm × 0.7 mm chip area was designed and manufactured based on an SMIC 0.18 μm EEPROM process. The simulations and measurements show that, compared to the conventional design, a reduced power loss of more than 20% is achieved without a loss in the chip area.

Effectiveness and cost-effectiveness of early assisted discharge for Chronic Obstructive Pulmonary Disease exacerbations: the design of a randomised controlled trial

BackgroundExacerbations of Chronic Obstructive Pulmonary Disease (COPD) are the main cause for hospitalisation. These hospitalisations result in a high pressure on hospital beds and high health care costs. Because of the increasing prevalence of COPD this will only become worse. Hospital at home is one of the alternatives that has been proved to be a safe alternative for hospitalisation in COPD. Most schemes are early assisted discharge schemes with specialised respiratory nurses providing care at home. Whether this type of service is cost-effective depends on the setting in which it is delivered and the way in which it is organised.Methods/DesignGO AHEAD (Assessment Of Going Home under Early Assisted Discharge) is a 3-months, randomised controlled, multi-centre clinical trial. Patients admitted to hospital for a COPD exacerbation are either discharged on the fourth day of admission and further treated at home, or receive usual inpatient hospital care. Home treatment is supervised by general nurses. Primary outcome is the effectiveness and cost effectiveness of an early assisted discharge intervention in comparison with usual inpatient hospital care for patients hospitalised with a COPD exacerbation. Secondary outcomes include effects on quality of life, primary informal caregiver burden and patient and primary caregiver satisfaction. Additionally, a discrete choice experiment is performed to provide insight in patient and informal caregiver preferences for different treatment characteristics. Measurements are performed on the first day of admission and 3 days, 7 days, 1 month and 3 months thereafter. Ethical approval has been obtained and the study has been registered.DiscussionThis article describes the study protocol of the GO AHEAD study. Early assisted discharge could be an effective and cost-effective method to reduce length of hospital stay in the Netherlands which is beneficial for patients and society. If effectiveness and cost-effectiveness can be proven, implementation in the Dutch health care system should be considered.Trial registrationNetherlands Trial Register NTR1129.

Introducing the national COPD resources and outcomes project.

BackgroundWe report baseline data on the organisation of COPD care in UK NHS hospitals participating in the National COPD Resources and Outcomes Project (NCROP).MethodsWe undertook an initial survey of participating hospitals in 2007, looking at organisation and performance indicators in relation to general aspects of care, provision of non-invasive ventilation (NIV), pulmonary rehabilitation, early discharge schemes, and oxygen. We compare, where possible, against the national 2003 audit.Results100 hospitals participated. These were typically larger sized Units. Many aspects of COPD care had improved since 2003. Areas for further improvement include organisation of acute care, staff training, end-of-life care, organisation of oxygen services and continuation of pulmonary rehabilitation.ConclusionKey Points: positive change occurs over time and repeated audit seems to deliver some improvement in services. It is necessary to assess interventions such as the Peer Review used in the NCROP to achieve more comprehensive and rapid change.

Theoretical prediction on the wavelength–temperature shift in pulsed TE CO 2 lasers

The wavelength–temperature shift observed in pulsed TE CO 2 lasers is discussed theoretically by means of Six-temperature model rate equations for tunable TE CO 2 lasers. Numerical calculations of the temperature–wavelength shift in a pulsed TE CO 2 laser with a simple plano-concave stable resonator, whether excited by conventional low-inductance fast-discharge scheme or by a long-pulse Pulser/sustainer discharge scheme, show that the laser output wavelengths are within the 10P branch as the ambient temperature varies from 228 to 338 K, but will change as the ambient temperature varies. The laser output wavelengths will move to the transition lines with longer wavelengths in the 10P branch as the ambient temperature increases and vice versa. The calculated results also illustrate that near the ambient temperature of 310 K, the laser is more likely to operate on multi-transition lines. Considering this wavelength–temperature shift, the chilling device adopted in high-power high repetition rate TE CO 2 lasers is important in maintaining a stable laser output spectra as well as a stable laser output power. The numerical results also suggest that a frequency agile resonator is highly recommended if stable laser output spectra are required in TE CO 2 lasers.