Short Return Times Research Articles

How to design subsidy policies to better encourage travelers to use car-sharing instead of private cars? An evolutionary game study

Car-sharing is a travel mode that can serve as an alternative to private cars, helping to reduce urban pollution. However, currently, there is a low willingness among travelers to use car-sharing, which is reflected in both low market penetration and user frequency. Therefore, it is essential for the government to encourage the use of car-sharing by providing subsidies. To better encourage the usage of car-sharing, this paper applies a two-fold evolutionary game model involving travelers and the government to explore the impact of subsidies on travelers’ choices, and the factors that could affect the subsidies’ efficiency. A simulation, using data from Beijing, was conducted to determine the implications of subsidy policies. The results show that a mileage-based subsidy and a fixed subsidy are applicable to travel of high and low mileages respectively, and under both subsidy modes, subsidies for trips with short duration or short pick-up and return time are more effective. Furthermore, we find that the efficiency of subsidies increases as the scale of car-sharing users, demand elasticity, or total number of travelers increases. Additionally, the subsidy levels should be lower than the environmental benefits of car-sharing but higher than the difference in travel costs between private cars and car-sharing. Future work will involve other game players such as car-sharing operators in order to draw deeper conclusions, and will involve the collection of data from more countries and cities to develop the robustness of the conclusions.

Pathways to exploit the multi-spot scanning strategy in electron beam additive manufacturing for control of microstructure and defect density

The goal of this study is to investigate the impact of beam deflection pattern characteristics on microstructure and porosity formation during Powder Bed Fusion Electron Beam Melting (PBF-EB/M) processing of Inconel 718. Specifically, the complex interplay between “beam return time” and “beam jump distance” and their influence on heat accumulation, porosity, and grain formation is explored. The findings reveal that beam jump distance plays a critical role in the transition from columnar to equiaxed solidification, while beam return time is essential for achieving optimal heat accumulation and minimizing porosity. By controlling these two universal beam deflection pattern characteristics, a novel multi-spot scanning strategy was developed, enabling the formation of a fine-grained equiaxed microstructure. It is demonstrated that sufficient heat accumulation is essential for a pore-free bulk material and can be achieved by short beam return times or small beam jump distances. However, for equiaxed grain formation, a large beam jump distance, i.e., a wide distribution of melt pools, is required. Therefore, heat accumulation must be controlled by means of the beam return time if equiaxed grains are aimed for. Additionally, it is found that higher beam currents are beneficial for equiaxed grain formation, but the strongest impact on the columnar to equiaxed transition is attributed to the beam movement pattern itself. This approach offers insights into microstructure control and process reliability, regardless of the specific PBF technique employed, and enables application-specific microstructure design of Inconel 718.

Factors Influencing the Uptake of Cervical Cancer Screening Services among Women Attending Gynecological OPD at KIUTH, Ishaka-Bushenyi, South Western Uganda

This work aimed to determine the factors influencing uptake of cervical cancer screening services among women attending gynecologic OPD at KIUTH, Ishaka-Bushenyi, South-western Uganda. A cross sectional study design and Quantitative approach was used. 100 women attending gynecologic OPD at KIUTH were selected using Kish Leslie formular. Data collected using a questionnaire was entered and analyzed using SPSS, presented in frequency, percentage and P-values tables. 41.2% were aged 25-31 years and the minority 2.0% being >45 years. 65.7% coming away from Ishaka; married 73.7% for 1-5 or 11-20 years each accounting for 32.5%. 37.4% while 30(30.3%) reached tertiary education level. 42.4% were unemployed whereas 7.1% were simply housewives. 50.0% had 2-4 children, and only 18.3% had <2 children. 86.9% were aware while 13.1% who weren’t. 56.8% got their information concerning cervical cancer and its screening from health facility compared to 3.7% from press. 34.7% had knowledge on screening recommendation among adult women who specified it being 22.1% every three years and 12.6% yearly. 88.4% specified it to be treatable if detected early with a P-value=<0.01*, 73.5% knows a local health facility offering the services; p-value=0.05, 53(62.4%) of 62.2% claim that results return time could influence the testing uptake, pvalue=0.18, also, 89.2% agreed that Recommendation/counseling affects the uptake of cervical cancer screening/testing p-Value=0.05, as well as having tested before 43.4% already tested had a p-value=0.05. Long distance to HF affects 75.9% aware of screening of 77.1% p-value=0.49, cervical test cost affect with 75.6% aware of the services p-value=0.55, and Gender of HW where 39.5% who were aware of the services out of 47.5% agreed that it affects uptake p-value=<0.001. According to the study findings, awareness/knowledge of cervical cancer screening/testing services among women attending KIUTH stands at 86.9%; whose info is mostly from health facility and Television/Radio. Early detection; availing of local health facility, short results return time, Recommendation/counselling and having tested before increases uptake whereas the long distance to the health facility, cervical test cost and longest distances reduces uptake of cervical cancer and screening services/testing. Keywords: Cervical cancer, Screening services, Healthy facility, Women, OPD.

The shape of the Himalayan “Arc”: An ellipse pinned by syntaxial strike-slip fault tips

Trans-Himalayan geodetic data show that, between both syntaxes, India/Asia convergence is steadily oriented ≈ N20°E. However, surface faulting near both syntaxes, along the 2005 and 1950 earthquake ruptures, imply long-term thrusting directed ≈ 130° apart, and post-LGM (last Glacial Maximum) shortening rates of ≈ 5 to 6 mm/y, ≈ 2 to 3 times slower than in Nepal (≈ 15 to 20 mm/y). Syntaxial earthquakes' return-time are also ≈ 3 times longer (>2,000 y) than in Nepal (≈ 700 y). In a structural frame centered halfway between the syntaxial cusps, the tectonic features of the range show remarkable symmetry. In map view, the overall shapes of the Main Front Thrust (MFT) and the Main Central Thrust (MCT) closely fit ellipses, with major-to-minor axis ratios of ≈ 2.5 to 3. This suggests that the range growth atop subducting India is "pinned" by the strike-slip faults that bound it to the east and west. Discrete Element Modeling corroborates a late-Tertiary elliptical range growth. This accounts for the ≈ 65° angles and twofold to threefold decrease in active thrusting between Nepal and the syntaxes, for the maximum Himalayan heights (≥8,000 m), larger magnitudes (≥8), and shorter return-time (≈ 700 y) of great earthquakes in Nepal, for the existence of two 500- to 600 km-long, south-concave mountain ranges north of both syntaxes and for the ≈ 9 mm/y, N100 to 110°E extension across southern Tibet. It also suggests that predictions of impending or frequent great earthquakes in the eastern- and westernmost Himalayas may be overstated.

Green algae monitoring via ground-based GNSS-R observations

Outbreaks of harmful algal blooms (HABs) exhibit high frequency, large range and damage aggravation characteristics, but existing monitoring methods, such as artificial and optical near-infrared remote sensing, cannot accommodate these characteristics. We propose a new method for monitoring green algae using Global Navigation Satellite System Reflectometry (GNSS-R) observations. The basic principle states that changes in the seawater dielectric constant and sea surface roughness due to the emergence of green algae lead to an increase in brightness temperature, which can be inverted based on the reflection time delay waveform. Shipboard reflection waveform data collected during an Enteromorpha prolifera outbreak in the Qingdao sea area were used for model development and validation of the detection and estimation performance. The results indicated that the root mean square error of GNSS-R-based inversion of the green algae density was 6.74%, indicating the potential of GNSS-R technology for rapid preliminary monitoring of green algae. Moreover, the advantages of a low cost, short return time and no climatic limitations support GNSS-R technology as a new and efficient means of green algae monitoring.

Economic and thermodynamic comparison of enhanced recycle split vapor processes for ethane recovery under different rich feed compositions

Based on the recycle split vapor (RSV) process for ethane recovery, this paper proposes three primary improved processes, and in China, five rich feed compositions are selected as preliminary data. We use economic and thermodynamic analysis methods to compare and analyze RSV and its improved processes comprehensively. The comparative analysis results show that: ①The enhanced techniques all show a certain energy-saving effect, especially it is evident for the modified recycle split vapor with liquid flashing (RSVF) process to save energy; ②The geometric structure of the plate-fin heat exchanger inside the cold box significantly affects its capital cost, the design of the plate-fin heat exchanger in the corresponding cold box is basically the same, with slight differences under different feed conditions; ③The compressors and expander are the most prominent investment types of equipment, and their purchase costs accounting for about 70% of the total purchased equipment costs. The values of financial net present value (FNPV) of the improved processes are all greater than zero under the operating conditions in this study, which can meet the profitability required by the benchmark rate of return. The project has a more significant return on investment and shorter return time; ④The improved processes under five feeds show excellent performance and adaptability: the larger GPM (gallons per thousand cubic feet) values of feed compositions, the more apparent the energy saving. The main contributors to the exergy destruction are towers, compressors, expander, and cold boxes; ⑤Compared with the improved recycle split vapor with gas extraction (RSVG) and supplemental rectification with compression and recycle split vapor (SRCR) processes, the improved RSVF process has a better pre-separation effect for heavy hydrocarbons by adding a flash separator, which makes this process have less exergy destruction and enormous energy-saving potential.

Laparoscopic Totally Extraperitoneal Hernia Repairs: a Case Series Analysis

Traditionally, inguinal hernias have been treated with open Lichtenstein hernioplasty. But in the last 2 decades, the trends have changed with the introduction of laparoscopic inguinal hernia repair techniques mainly by totally extraperitoneal herniorrhaphy. This was a case series analysis of 160 consecutive patients who underwent totally extraperitoneal repair and were included accrual between January 2015 and August 2018 in our single tertiary center. Patient demographics, details of the surgery, postoperative Visual Analogue Scale, return time to work, early and late postoperative complications, recurrence, and chronic pain were evaluated. A hundred seventy-eight repairs were performed in the study cohort (median age, 46.3 years; range, 22–84 years; men, 93%). The mean follow-up was 15 months (range = 12–30). Mean hospital stay time was 22.6 h (range 15–27). The mean surgery time was 55 min (range 35–110). Second day postoperative mean Visual Analogue Scale was 2.3 (range 1–5). The mean return time to their routine work was 8.3 days (range 5–17). Seroma (10%), scrotal pain (9%), scrotal paresthesia (6%), and hydrocele (6%) were the most commonly noted complications. Recurrence was detected in 4 (2.5%) patients. Recurrences were noted at 1st week and 6th month following surgery. Chronic groin pain was reported by 4 (2.5%) patients. Totally extraperitoneal hernia repair has become increasingly applicable among surgeons due to less postoperative pain, short return time to routine work, acceptably few complications, and recurrence rates compared with the other inguinal herniorrhaphy techniques.

Thermal and economic analysis of preinsulated and twin-pipe heat network operation

This study focuses on the economic analysis of the heating network modernization by using preinsulated pipes and twin-pipes. The cost analysis is based on different type, diameter, and technological diagrams of different heating network pipe variants (from DN25to DN100) and various types of insulation. Net present value (NPV) analysis comparing a five variants of the heating network pipes (Case 0: Pipes with insulation PUR standard; Case 1: Pipes with insulation PUR plus; Case 2: Pipes with insulation PEX standard; Case 3: Twin-Pipes with insulation PUR; Case 4: Twin-Pipes with insulation PEX). The value of NPV, which is the highest (NPV = 7000 €, DN65, case 2 and NPV = 5200 €, DN50, case 4) among presented variants is the best choose to consider during the investment. Despite the higher prices of Twin Pipe system, they are more profitable due to shallow heat transfer losses. Heat losses are calculated for various heating networks, including preinsulated and twin-pipe heating networks. The remaining heat loss calculation is based merely on temperature levels and thermal resistance factors (in the ground), determined using the pipe dimensions and materials. It is found that the most cost-effective from an economic point of view is the use of TwinPipe system. These pipes are more expensive, but the heat losses that occurs during their use are much smaller compared to preinsulated pipes. Short return time of such an investment (6–7 years) with 100 m of pipe installed and positive NPV causes that this type of pipes is the best investment in the case of district heating networks. The results shown that Case 3 (PEX insulation) is more economicaly beneficial than Case 4 (PUR insulation).

A CYGNSS‐Based Algorithm for the Detection of Inland Waterbodies

AbstractThe Cyclone Global Navigation Satellite System (CYGNSS) is a new constellation of eight low Earth orbiting spacecrafts that receive both direct and reflected signals from GPS satellites. Coherent reflection of the GPS signal from standing water over land results in a high surface reflectivity signal in the CYGNSS data. An image processing algorithm is presented, which leverages the surface reflectivity signal to produce a watermask of inland waterbodies at 0.01° × 0.01° spatial resolution. The watermask is compared to hand‐drawn maps of inland waterbodies, as well as to the MODIS watermask product. We find that the CYGNSS watermask provides accurate, time‐varying maps that are able to resolve changes in lake and river position and extent. With CYGNSS' short return time, watermasks can be generated using as little as half a month of data to produce near‐real‐time maps of flooding events.

Energy saving and user satisfaction for a new advanced public lighting system

The retrofit of urban lighting systems is often an advantageous means of achieving notable energy savings and improvements in the quality of light. User habits, expectations and lifestyle can contribute to the design of these systems, for example in deciding on the most appropriate control strategies or the light quality. The influence of such variables can be extended to the overall system performance. This paper presents a method of street lighting design based on two kinds of analysis carried out in a defined test area: measurements (by means of a monitoring study) and user preferences (by means of a survey). The results of this data analysis create the basis for the final design step. The proposed method is applied in a case study: the lighting system of the outdoor areas of the University of Palermo campus (Italy). The results show that the proposed method can be used to optimise the performance of a lighting plant in terms of energy saving and quality of light, while also taking into account the opinions of local users. Indeed, the results of the survey show that 81% of the users feel safe in test areas, 80% declare very good satisfaction with the project, and the totality of the sample would like the implementation of new features embedded in the lighting infrastructure. Expected results of energy savings in the entire campus will be about 70% with a short investment return time (3–4 years).

On the linkage between runoff generation, land drainage, soil properties, and temporal patterns of precipitation in agricultural floodplains

Accurate awareness of how rainfall, land use changes, and soil types control water fluxes in agricultural floodplains remains a crucial challenge in water resource research. This study examines soil moisture conditions, soil texture and rainfall characteristics, together with different artificial drainage network structures covering a time-span of 100 years (1924–2010), as drivers for runoff production in an agricultural floodplain. The research incorporates a multiple-layer generalised Green-Ampt approach to simulate water infiltration into the ground. Once the storage offered by the soil is saturated, a portion of the surface storage provided by the drainage network satisfies the infiltration capacity, thus delaying runoff. The watershed response is defined by the uNSI (updated Network Saturated index, (Sofia and Tarolli, 2017), that indicates the moment the available storage (soil + network) is 100% saturated. The results highlighted how interlocking relations between soil properties, the geometry of the network and temporal variations of precipitation determine runoff generation timing. For short return times, intense rainfalls tend to produce a quicker response in areas with soils prone to saturation, and with decreased network complexity. However, when the event magnitude increases, this combination of soil and network structure produces the fastest response when rainfall is more regular. Intense events in zones with soils with higher permeability produce a quicker response the simpler the network is. When soils are prone to runoff, and the network efficiency increases, runoff production is delayed in time. When soils have elevated permeability, and the network has a reduced efficiency and path heterogeneity, increasing the network simplicity would result in similar outcomes. Moreover, if the path heterogeneity and network efficiency increases, for a given network sinuosity, runoff generation would be delayed. Quantifying these effects is indeed crucial for many environmental problems, including the prediction of impacts of a changing climate and land use and the associated pressures.

L'intermittenza delle sorgenti del Torbidone nella Piana di Norcia: analisi delle fonti storiche a partire dal XIV secolo

In the Norcia plain (Umbria, Central Italy) the springs of Torbidone are characterized by a peculiar behavior, i.e. the periodical appearing and vanishing for years. The reasons of this peculiarity are not yet well defined.In the popular opinion, the springs has a periodicity of 7 years, at least until 1859 afterward the Norcia earthquake that was described in detail by Father Angelo Secchi, when started a more detailed collection of hydrologic data.Many authors described the prodigious of this springs and their periodically appearance. The first citations was in the half of XIV century by Fazio degli Uberti, that in his Dittamondo wrote about the seven years periodicity of the springs.Hereafter, many authors deal with this argument, whether by a scientific or juridical point of view.In recent time, some established a correlation between the seismicity of this part of the Central Apennine and these extraordinary springs; without a doubt, they re-appeared after the extremely intense seismic period that shaked this area in the August - October 2016. In fact, after these events the springs resurfaced again with a very high flow rate of about 1,500 l/s draining the Sibillini Mounts reservoir feed by the Castelluccio Plain hydrogeologic system.The springs disappeared after the 1979 Valnerina earthquake, evoking the correlation between the water flow and seismicity. To limit the increased water volume has been necessary to reshape the original fluvial bed reworked, over the time, by agriculture.This event highlight how the anthropization processes often forget the occurrence of natural events, even if they have short return times or a regular periodic.It is so necessary to understand that the historical research on the original bibliographic sources is essential to reconstruct in the right way the natural events effect, above all for those having a recurrent character.

Landscape selection by migratory geese: implications for hunting organisation

Over the last decades, many wild goose populations have increased significantly and are now causing conflicts with socioeconomic and biological interests. To mitigate impacts of rapid population increases, population control by increasing harvest has been attempted. In this study we seek to guide the design of a regional autumn goose hunting organisation in agricultural landscapes by identifying areas suitable for hunting, which have high probability of occurrence of pink‐footed geese Anser brachyrhynchus and/or a short return time by geese to fields subject to hunting. To identify areas suitable for hunting in Nord‐Trøndelag County, mid‐Norway, we used species distributions models (SDMs), a broadly accepted tool in conservation planning for spatial refuge organisation. The prediction was that the highest probability of goose occurrence exists for large fields, away from small roads and near water bodies serving as safe roosting sites. Additionally, return time was predicted to be shortest for large fields near roosting sites and away from big roads. A combined map of goose occurrence and return time showed similar prediction for high goose occurrence and short return time; hence areas most suitable for hunting are large fields, close to roost sites and away from roads. If hunters and landowners are willing to coordinate goose hunting at a landscape level, they can use the prediction maps as guidance, with the likely benefit that they collectively can shoot more geese. Such local and regional organisation can become a powerful tool in the harvest management of geese.

Anaerobic Digestion of Spoiled Milk in Batch Reactors: Technical and Economic Feasibility

The economic feasibility of the energy conversion through anaerobic digestion of spoiled milk was assessed for the microscale biogas production and heating value was determined experimentally on a pilot plant with a mixture of spoiled milk and an inoculum previously optimized with Anaerobic Biomethanation Potential tests. Results shows that the feasibility of a 100 kWel plant is characterized by a quite short return time of the investment. Considering a discount rate of 5% and a timespan of investment equal to 20 years, payback period is equal to 8-9 years, Net Present Value is equal to 806,903 € and Internal Rate of Return is equal to 16%.

Return to Sport After Tibial Shaft Fractures: A Systematic Review.

Context:Acute tibial shaft fractures represent one of the most severe injuries in sports. Return rates and return-to-sport times after these injuries are limited, particularly with regard to the outcomes of different treatment methods.Objective:To determine the current evidence for the treatment of and return to sport after tibial shaft fractures.Data Sources:OVID/MEDLINE (PubMed), EMBASE, CINAHL, Cochrane Collaboration Database, Web of Science, PEDro, SPORTDiscus, Scopus, and Google Scholar were all searched for articles published from 1988 to 2014.Study Selection:Inclusion criteria comprised studies of level 1 to 4 evidence, written in the English language, that reported on the management and outcome of tibial shaft fractures and included data on either return-to-sport rate or time. Studies that failed to report on sporting outcomes, those of level 5 evidence, and those in non–English language were excluded.Study Design:Systematic review.Level of Evidence:Level 4.Data Extraction:The search used combinations of the terms tibial, tibia, acute, fracture, athletes, sports, nonoperative, conservative, operative, and return to sport. Two authors independently reviewed the selected articles and created separate data sets, which were subsequently combined for final analysis.Results:A total of 16 studies (10 retrospective, 3 prospective, 3 randomized controlled trials) were included (n = 889 patients). Seventy-six percent (672/889) of the patients were men, with a mean age of 27.7 years. Surgical management was assessed in 14 studies, and nonsurgical management was assessed in 8 studies. Return to sport ranged from 12 to 54 weeks after surgical intervention and from 28 to 182 weeks after nonsurgical management (mean difference, 69.5 weeks; 95% CI, –83.36 to −55.64; P < 0.01). Fractures treated surgically had a return-to-sport rate of 92%, whereas those treated nonsurgically had a return rate of 67% (risk ratio, 1.37; 95% CI, 1.20 to 1.57; P < 0.01).Conclusion:The general principles are to undertake surgical management for displaced fractures and to attempt nonsurgical management for undisplaced fractures. Primary surgical intervention of undisplaced fractures, however, may result in higher return rates and shorter return times, though this exposes the patient to the risk of surgical complications, which include surgical site infection and compartment syndrome.

Predicting time to emergency department return for anxiety disorders and acute stress reactions in children and adolescents: a cohort study.

While studies indicate that few children with anxiety disorders receive specialized mental health care, significant knowledge gaps exist for the mental health care trajectory outside of specialized care. We examined whether physician-based care after an emergency department (ED) visit for mental health care predicted time to ED return. We conducted a retrospective cohort study using administrative data from Alberta, Canada. Included in the cohort were 8075 children <18 years discharged from an ED (104 EDs in total), April 2002-September 2010, following a visit for an anxiety disorder or acute stress reaction. We used a multivariable Cox proportional hazards model to estimate time to ED return for mental health care (censored at 90 days). The variables of interest were: number and type of physician visits 30 days after index visit. We adjusted for sociodemographics, clinical acuity, comorbidity, and recent history of ED mental health care in the model. Within 30 days of ED discharge, multiple physician follow-up visits were associated with shorter return time (adjusted HR 1.24, 95 % CI 1.08-1.43). A single physician follow-up visit was associated with longer return time (adjusted HR 0.68, 95 % CI 0.58-0.79). Physician follow-up visits for mental health care were associated with shorter return time (adjusted HR 2.5, 95 % CI 2.21-2.83). Following an index visit, ED return by children with anxiety disorders or acute stress reactions is associated with specific characteristics of subsequent physician visits. Improving physician use of evidence-based treatment and family access to coordinated services may reduce costly hospital-based care.

피부의 탄성변화에 따른 피부 가압과 복귀시간 측정을 통한 정량적 림프부종 진단 시스템 개발

Abstract: Lymphedema is a phenomenon in which fluid is accumulated inside tissues due to the damaged lymphaticsystems. Lymphedema can cause complications such as lymphangitis, infection, changes in skin texture, fibrosis, andlymphangiosarcoma. In this study, a lymphedema screening system based on the elasticity of the skin is proposedto easily quantify lymphedema. The developed probe consists of touch sensors, a load cell and hall-effect sensorsto measure the indentation force on the skin and the return time of the skin. The developed system can be usedto estimate the change in the elasticity of the skin to quantify lymphedema. The system was tested with a thyroidphantom and gelatin phantoms of different concentrations and the resulting force and the time were recorded. It wasfound that the increase in the elasticity leads to a higher indentation force and shorter return time. This shows thatthe developed system can monitor the change in the skin elasticity by measuring the return time and the indentationforce. The feasibility of the system in clinical applications will be evaluated in the future study.Key words: edema, lymphedema, skin elasticity, lymphedema screening, lymphedema examination

Observations and modelling of 1/&amp;lt;i&amp;gt;f&amp;lt;/i&amp;gt;-noise in weather and climate

Abstract. Data with power spectra close to S(f)~1/f is denoted as 1/f or flicker noise. High resolution measurements during TOGA/COARE for temperature, humidity, and wind speed (1\\,min resolution) reveal 1/f spectra while precipitation shows no power-law scaling during the same period. However, a binary time series indicating the precipitation events (1 for precipitation, 0 for no precipitation) shows a clear 1/f spectrum in line with the remaining boundary layer data. For extreme events in time series with 1/f spectra the return time distribution is well approximated by a Weibull-distribution for short and long return times. The daily discharge of the Yangtze river shows high volatility which is linked to the intra-annual 1/f spectrum. The discharge fluctuations detected in different time windows are represented by a single function (a so-called data collapse) similar to the universal behavior found for turbulence and various physical systems at criticality. The collapse is well described by the Gumbel distribution.

Revamping, Energy Efficiency, and Exergy Analysis of an Existing Upstream Gas Treatment Facility

Surface oil and gas treatment facilities in service for decades are likely to be oversized due to the natural depletion of their reservoirs. Despite these plants might have been designed modularly, meaning they comprise multiple identical units serving the same task, such units operate often in conditions far from the design. This work analyzes the revamping options of an existing upstream gas facility, chosen because representative of a wide set of plants. It presents a flexible process simulation model, implemented in the HYSYS environment and dynamically linked to an Excel spreadsheet, which includes the performance maps of all turbomachineries and the main characteristics of the investigated modifications. The model may be used to run simulations for various gas input conditions and to predict the performance over 1 year of operation and for different possible future scenarios. The first objective is to assess economically the considered options, which shall be applied only if yielding short return times of the investment since the reservoir is mature. Moreover, all options are appreciated adopting a figure of merit, here defined, that compares the overall energy consumption to the one calculated with state-of-the-art technologies. In addition, exergy and environmental analyses are executed.

A Perpetually Running ENSO in the Pliocene?

AbstractDifficulties remain with theoretical explanations of the apparent reduced zonal sea surface temperature gradient in the tropical Pacific of the Pliocene. One favored hypothesis is that it was a “permanent El Niño” state, with the warm phase of ENSO remaining fixed over millions of years. Here, an alternative is suggested—that there was a “perpetually running ENSO” with a shorter return time than is observed today, and that the apparently reduced zonal gradient is an alias–rectification of a high-frequency signal governed by the growth patterns of the foraminifera used to provide proxy temperatures. The hypothesis is probably testable in the modern ocean with comparatively modest measurements of foraminifera behavior in time.