Capacity Of Providers Research Articles

Cross-Border Capacity Planning in Air Traffic Management Under Uncertainty

In European air traffic management (ATM), it is an important decision how much capacity to provide for each airspace, and it has to be made weeks or even months in advance of the day of operation. Given the uncertainty in demand that may materialize until then along with variability in capacity provision (e.g., due to weather), Airspace Users could face high costs of displacements (i.e., delays and reroutings) if capacity is not provided where and when needed. We propose a new capacity sharing scheme in which some proportion of overall capacities can be flexibly deployed in any of the airspaces of the same alliance (at an increased unit cost). This allows us to hedge against the risk of capacity underprovision. Given this scheme, we seek to determine the optimum budget for capacities provided both locally and in cross-border sharing that results in the lowest expected network costs (i.e., capacity and displacement costs). To determine optimum capacity levels, we need to solve a two-stage newsvendor problem: We first decide on capacities to be provided for each airspace, and after uncertain demand and capacity provision disruptions have materialized, we need to decide on the routings of flights (including delays) as well as the sector opening scheme of each airspace to minimize costs. We propose a simulation optimization approach for searching the most cost-efficient capacity levels (in the first stage), and a heuristic to solve the routing and sector opening problem (in the second stage), which is [Formula: see text]-hard. We test our approach in a large-sized simulation study based on real data covering around 3,000 flights across Western European airspace. We find that our stochastic approach significantly reduces network costs against a deterministic benchmark while using less computational resources. Experiments on different setups for capacity sharing show that total variable costs can be reduced by more than 8% if capacity is shared across borders: even though we require that no airspace can operate lower capacities under capacity sharing than without (this is to avoid substitution of expensive air traffic controllers with those in countries with a lower wage level). We also find that the use of different technology providers is a major obstacle to reap the benefits from capacity sharing and that sharing capacities across airspaces of the same country may instead be preferred. History: This paper has been accepted for the Transportation Science Special Issue on Emerging Topics in Transportation Science and Logistics. Funding: This work was supported by the Horizon 2020 Framework Programme [893380]. Supplemental Material: The online appendix is available at https://doi.org/10.1287/trsc.2023.1210 .

Service availability and readiness assessment of COVID-19 disease management at different tiers of health service delivery in Bangladesh

Background: The world is passing through a hard time due to the highly infectious COVID-19 pandemic. Like other countries in the world, the Bangladesh government has taken various preventive measures. As part of this, the availability and readiness of different health facilities is crucial. Objective: The study aimed to assess availability and readiness based on logistics, workforce, clinical management, and IPC. Methods: A cross-sectional quantitative study was conducted from August 20 to September 30, 2021, which comprised a health facility survey with a sample of 210. The health facilities included all three tiers of hospitals, covering 24 districts of eight divisions. All COVID-19 dedicated hospitals were included in this survey. The questionnaire consisted of a standard checklist developed by WHO, DGHS, and CDC. Results: The overall scores for ICU, HDU, and ventilation service were 76.8%, 87.5%, and 85.7%, respectively, but they were almost missing in Upazila health complex and below the average in non-dedicated hospitals. All (100%) secondary and tertiary level hospitals had a 24-hour staffed emergency unit, with dedicated hospitals outperforming non-dedicated hospitals (99.2% vs 98.7%). Above 90% of hospitals in different tiers had hand hygiene supplies and respiratory hygiene supplies for staff and patients, 98% of the primary level hospitals displayed instructions on hand and respiratory hygiene practices. On the other hand, 94.9% of secondary level hospitals had clearly identified and separated COVID-19 isolation areas from non-COVID-19 areas; 82.1% of secondary level hospitals had service providers (MOs) who used PPE; 97.4% had routine cleaning and disinfection of ambulances done according to IPC guidelines; and 64.1% had staff of laboratory, laundry, food services, and waste management teams who used appropriate PPE. Secondary level hospitals had a better availability of PPE compared to primary and tertiary level hospitals, which consisted of protective gowns (87.8%), disposable latex gloves (examination) (92.5%), goggles, protective (82.9%), face shields (72.5%), respirator masks (N95 or FFP2) (75.0%), and masks, medical/surgical (97.6%) available for all health service providers. Almost 26.2% facility have PCR testing lab and almost all (96.7%) the facilities have specimen collection system in their facility. Conclusion: The service availability and readiness regarding COVID-19 among different tiers of health facilities in Bangladesh are not adequate. We need more support for disease detection capacities through provision of technical expertise, laboratory equipment and increase capacity of the secondary and primary health care tier along with national capacity for covid-19 testing. Bangladesh Medical Res Counc Bull 2022; 48: 160-171

A conceptual model for enabling sustainable management of soil-sediment-water ecosystems in support of European policy

Abstract The health of soil-sediment-water ecosystems is under pressure from economic activities and a changing climate. This decreases health and hampers the service provision capacity of these ecosystems and thus impacts human well-being. Protecting and where feasible restoring of ecosystem health has currently become the key European environmental policy objective and for this it is needed to take an entire system approach and engage stakeholders. ‘Entire’ means that soil, sediment and water are regarded as closely interlinked environmental matrices that need to be managed by taking a ‘river (or mountain) to sea’ perspective, crossing spatial, discipline, political and cultural boundaries. This paper presents a conceptual model to support that purpose. Essentially, the conceptual model presents an approach for ecosystem-based management aimed to achieve healthy ecosystems, i.e. soil-sediment-water ecosystems that have the continued capacity to support ecosystem services to the benefit of their users. The model proposes a cyclic (iterative, learning-by-doing) approach and integrates soil-sediment-water, ecosystems, ecosystem services, users (stakeholders), pressures, information, management strategy and program of measures as building blocks. To successfully apply the model, it is above all needed to take an entrepreneurial approach, i.e. leave comfort zones, take an adventurous road, learn together to manage together, be adaptive and consider other than only command-and-control solutions. Furthermore, authorities should become facilitative leaders to engage users in co-creation of an ecosystem-based management strategy. Real live and place-based experimenting with multiple stakeholders, such as in the Living Labs and Lighthouses that are proposed in the EU soil mission, may provide an ideal instrument for such application, i.e. where the conceptual model can be used and support the achievement of European environmental policy objectives.

Investigating rapid diagnostic testing in Kenya’s health system, 2018–2020: validating non-reporting in routine data using a health facility service assessment survey

BackgroundUnderstanding the availability of rapid diagnostic tests (RDTs) is essential for attaining universal health care and reducing health inequalities. Although routine data helps measure RDT coverage and health access gaps, many healthcare facilities fail to report their monthly diagnostic test data to routine health systems, impacting routine data quality. This study sought to understand whether non-reporting by facilities is due to a lack of diagnostic and/or service provision capacity by triangulating routine and health service assessment survey data in Kenya.MethodsRoutine facility-level data on RDT administration were sourced from the Kenya health information system for the years 2018–2020. Data on diagnostic capacity (RDT availability) and service provision (screening, diagnosis, and treatment) were obtained from a national health facility assessment conducted in 2018. The two sources were linked and compared obtaining information on 10 RDTs from both sources. The study then assessed reporting in the routine system among facilities with (i) diagnostic capacity only, (ii) both confirmed diagnostic capacity and service provision and (iii) without diagnostic capacity. Analyses were conducted nationally, disaggregated by RDT, facility level and ownership.ResultsTwenty-one per cent (2821) of all facilities expected to report routine diagnostic data in Kenya were included in the triangulation. Most (86%) were primary-level facilities under public ownership (70%). Overall, survey response rates on diagnostic capacity were high (> 70%). Malaria and HIV had the highest response rate (> 96%) and the broadest coverage in diagnostic capacity across facilities (> 76%). Reporting among facilities with diagnostic capacity varied by test, with HIV and malaria having the lowest reporting rates, 58% and 52%, respectively, while the rest ranged between 69% and 85%. Among facilities with both service provision and diagnostic capacity, reporting ranged between 52% and 83% across tests. Public and secondary facilities had the highest reporting rates across all tests. A small proportion of health facilities without diagnostic capacity submitted testing reports in 2018, most of which were primary facilities.ConclusionNon-reporting in routine health systems is not always due to a lack of capacity. Further analyses are required to inform other drivers of non-reporting to ensure reliable routine health data.

Hybrid Learning based Radio Resource Management in 5G Heterogeneous Networks

Ultradensification using different types of small cells (SCs) is one of the key enabling solutions to meet the multiple stringent requirements of 5G cellular networks. However, radio resource management (RRM) in ultra-dense heterogeneous networks (HetNets) is not easy due to interferences in multi-tiered architecture and dynamic network conditions. Interferences in 5G HetNets can be efficiently managed only through the techniques which are adaptive and self-organizing to handle dynamic conditions in 5G HetNets. In this article, a machine learning (ML) based self-adaptive resource allocation scheme is proposed based on the combination of independent and cooperative learning and evaluated for ultra-dense 5G HetNets. The proposed scheme aims to improve the QoS of all users associated with different network tiers in ultra-dense HetNets simultaneously. The proposed solution adaptively optimizes the SCs transmit power either through independent learning or cooperative learning based on the varying density of small cells to minimize the interferences and ensure minimum QoS requirements for all users in different network tiers. The proposed scheme not only maintains the minimum required capacities for QoS provision to all users simultaneously but has also shown a significant improvement in the capacities of users in different network tiers in high interference scenarios as compared to the use of a single learning scheme.

Implementing criteria-led discharge for acute admissions to facilitate the elective recovery from COVID-19: an example in acute tonsillitis

BackgroundHealthcare systems face unprecedented numbers of patients waiting for elective treatments in the wake of the COVID-19 pandemic. Hospitals must urgently optimise patient pathways and build capacity to meet the...

Land Administration As-A-Service: Relevance, Applications, and Models

The ‘as-a-Service’ (aaS) concept of the IT sector is suggested to reduce upfront and ongoing costs, enable easier scaling, and make for simpler system upgrades. The concept is explored in relation to the domain of land administration, with a view to examining its relevance, application, and potential adaptation. Specifically, these aspects are analysed against the long-standing problem of land administration system maintenance. Two discrete literature reviews, a comparative analysis, and final modelling work constitute the research design. Of the 35 underlying land administration maintenance issues identified, aaS is found to directly respond to 15, indirectly support another 15, and provide no immediate benefit to 5. Most prominent are the ability of aaS to support issues relating to financial sustainability, continuous innovation, and human capacity provision. The approach is found to be already in use in various country contexts. It is articulated by the UNECE as one of four scenarios for future land administration development. In terms of adaptation, the 4-tier framework from Enterprise Architecture—consisting of Business, Application, Information, and Technology layers—is used to model and describe five specific aaS approaches: (i) On Premises; (ii) Basic Outsourcing; (iii) Public Private Partnership; (iv) Fully Privatised; and (v) Subscription. Several are more theoretical in nature but may see future adoption. Each requires further development, including case analyses, to support more detailed definitions of the required underlying legal frameworks, financial models, partnerships arrangements, data responsibilities, and so on. Decisions on the appropriate aaS model, and the application of aaS more generally, are entirely dependent on the specific country context. Overall, this work provides a platform for land administration researchers and practitioners to analyse the relevance and implementation options of the aaS concept.

Correlation between Soil Carbon Potential and Soil Quality Index in Various Types of Dry Land Use in Aceh Besar District

Soil quality is a useful concept when assessing the sustainability of an agricultural business and demonstrating the ability of soil to maintain plant and animal productivity, improve water and air quality, and protect human health. SQI is a soil variable with the following characteristics: 1) well correlated with ecosystem processes; 2) integration of physical, chemical, and biological soil properties; 3) good sensitivity to human-induced soil changes; 4) simple measurement and interpretation; and 5) Reproducibility Soil quality index (SQI) is a diagnostic procedure to evaluate soil function and overall health. This research was carried out on a unit of land in a dry area in Aceh Besar District with a study area of 239,439.63 ha. Analysis of biomass samples and soil samples was carried out at the Laboratory of Soil and Plant Sciences and Soil Physics Laboratory, Faculty of Agriculture, University of Syiah Kuala. The tools used in this study include a set of computers with the Microsoft Windows 10 operating system that are equipped with several software for analysis, writing instruments, and other supporting tools. The main materials used in this study were soil samples, tree diameter measurement data, and land use maps, including geology, climate, slope class, soil, and topography. The results of the correlation analysis test showed a value of 0.6358. This shows that the relationship between soil C potential and soil quality index is a strong correlation. The distribution of carbon in the soil also has a close relationship with the soil quality index and is an effort to maintain carbon stocks in the soil. C - organic content is a very important parameter in compiling soil quality index criteria. Soil quality can be affected by many factors, such as parent material, environmental factors, land use type, and human activities. The percentage of soil organic C is an indicator of the percentage of soil organic matter (BOT), and BOT is able to improve soil structure and aggregates. Soil organic carbon (SOC) concentration is closely related to soil quality and vegetation productivity. This relationship occurs because of the many contributions of soil carbon to soil properties such as the improvement of soil structure and water retention, provision of cation exchange capacity, and supply of plant nutrients through mineralization. This effect is especially important in small-scale tropical farming systems where the use of external inputs is often limited, and SOC concentrations have been positively correlated with yield levels for a variety of tropical soils.

Анализ эффективности различных схем организации неортогонального множественного доступа NOMA

Sixth generation 6G (Sixth Generation) wireless communication systems are the most popular direction of articles and literature. The main interest is the future standard of the 3GPP project, which defines the key technologies that will be used in the new generation of wireless communication systems. NOMA (Non-orthogonal multiple access) technology is one of the fundamental technologies for 6G systems. Using NOMA technology, it is possible to implement the concept of "Massive connectivity" for 6G systems, which assumes the provision of high capacity of future communication systems and more efficient use of the radio frequency spectrum. There are several schemes for organizing multiple NOMA access. The most promising of them are SCMA (Sparse Code Multiple Access) –and WSMA (Welch-bound equality Spread Multiple Access). The main goal of this article is to compare the performance of non-orthogonal SCMA and WSMA schemes.

Generation Capacity Expansion Considering Hydrogen Power Plants and Energy Storage Systems

The design of decarbonized power systems is one of the most relevant and challenging problems that power system planners are facing nowadays. In this sense, the replacement of natural gas turbines by H2-fired gas turbines in future power systems may constitute a solution to reduce greenhouse gas emissions maintaining the dispatchability of the system. This work develops a novel generation capacity expansion formulation that considers the possibility of installing new H <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> -fired gas turbines, as well as renewable generation and different storage technologies. The proposed model also determines the investment decisions related to the installation of electrolyzers to produce H <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> , as well as H <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> storage facilities. The provision of reserve capacity by generating units, storage and electrolyzers is also considered to determine the optimal investment decisions. The uncertainty related to the demand growth and the capital costs of electrolyzers and H <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> storage is explicitly considered by using a stochastic programming formulation. A realistic case study based on an actual isolated power system is solved to test the proposed formulation. The obtained results indicate that H <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> power plants are installed in all cases in which this technology is available. Additionally, the capacity installed of electrolyzers is over 2.5 times higher than that of H <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> power units.

Optimal Algorithms for Right-sizing Data Centers

Electricity cost is a dominant and rapidly growing expense in data centers. Unfortunately, much of the consumed energy is wasted, because servers are idle for extended periods of time. We study a capacity management problem that dynamically right-sizes a data center, matching the number of active servers with the varying demand for computing capacity. We resort to a data-center optimization problem introduced by Lin, Wierman, Andrew, and Thereska [ 25 , 27 ] that, over a time horizon, minimizes a combined objective function consisting of operating cost, modeled by a sequence of convex functions, and server switching cost. All prior work addresses a continuous setting in which the number of active servers, at any time, may take a fractional value. In this article, we investigate for the first time the discrete data-center optimization problem where the number of active servers, at any time, must be integer valued. Thereby, we seek truly feasible solutions. First, we show that the offline problem can be solved in polynomial time. Our algorithm relies on a new, yet intuitive graph theoretic model of the optimization problem and performs binary search in a layered graph. Second, we study the online problem and extend the algorithm Lazy Capacity Provisioning (LCP) by Lin et al. [ 25 , 27 ] to the discrete setting. We prove that LCP is 3-competitive. Moreover, we show that no deterministic online algorithm can achieve a competitive ratio smaller than 3. Hence, while LCP does not attain an optimal competitiveness in the continuous setting, it does so in the discrete problem examined here. We prove that the lower bound of 3 also holds in a problem variant with more restricted operating cost functions, introduced by Lin et al. [ 25 ]. In addition, we develop a randomized online algorithm that is 2-competitive against an oblivious adversary. It is based on the algorithm of Bansal et al. [ 7 ] (a deterministic, 2-competitive algorithm for the continuous setting) and uses randomized rounding to obtain an integral solution. Moreover, we prove that 2 is a lower bound for the competitive ratio of randomized online algorithms, so our algorithm is optimal. We prove that the lower bound still holds for the more restricted model. Finally, we address the continuous setting and give a lower bound of 2 on the best competitiveness of online algorithms. This matches an upper bound by Bansal et al. [ 7 ]. A lower bound of 2 was also shown by Antoniadis and Schewior [ 4 ]. We develop an independent proof that extends to the scenario with more restricted operating cost.

Mental health mobile application self-help for adolescents exhibiting psychological distress: A single case experimental design.

The present demand for child and adolescent mental health services exceeds the capacity for service provision. Greater research is required to understand the utility of accessible self-help interventions, such as mobile apps. This study sought to investigate whether use of a mental health app, underpinned by CBT, led to changes in psychological distress amongst adolescents. Mechanisms of change were examined, specifically whether changes are attributable to cognitive strategies. This study utilised a multiple-baseline single-case experimental design, tracking variables across baseline and intervention phases. Surveys assessing participant experience were also administered. Five participants with moderate-to-severe levels of psychological distress engaged with a CBT-based app over five weeks. Participants were recruited from both a well-being service and the general population. Supplementary weekly calls to participants offered clarification of app content. A small overall effect of the intervention of psychological distress was evident; however, outcomes were dependent on the analysis conducted. The intervention appeared to promote an increase in use of adaptive cognitive strategies but not negative thinking styles. The CBT app did not promote changes in participant well-being. Participant feedback highlighted practical challenges of utilising the app. The clinical benefits of app-based CBT were small, and a range of barriers to engagement were recognised. While further research is required, caution should be exercised in the interpretation of studies reporting on app effectiveness.

Implementing proposed reforms of the Mental Health Act for people with intellectual disability and autism: the perspective of multidisciplinary professionals in intellectual disability teams.

A recent government white paper sets out proposals for reforms to the Mental Health Act 1983 (MHA). Some of these proposals affect people with intellectual disabilities and/or autism. To explore both positive and unintended negative effects of the proposed reforms by gathering the perspectives of healthcare workers from multiple disciplines, working with intellectual disability and/or autism in community and in-patient settings. A 14-question electronic questionnaire, comprising free-text, multiple choice and five-point Likert scale responses, was sent out via email between April and July 2021, to all multidisciplinary team professionals working in specialist intellectual disability community and in-patient teams in Hertfordshire Partnership University NHS Foundation Trust. There were 45 responders, of whom 53% worked in in-patient settings and 47% in out-patient teams. Respondents comprised healthcare professionals from multiple disciplines, 80% of which were non-medical. Most responders agreed with the general principles of the proposed reforms. However, 80% felt there would be potentially unintended consequences, and 76% thought that substantial investment in community services was required in advance of the proposed reforms. The proposed MHA reforms may have unintended consequences for people with intellectual disabilities and/or autism. The findings of this study raised key concerns that need to be explored further and addressed before the MHA reforms are implemented. These include community provision, safeguards and use of the Mental Capacity Act, the potential for under or overdiagnosis of mental illness, and effects associated with the criminal justice system.

Optimization-based investigation of different repurposing concepts for Austrian coal-fired power plants

Even though the current war in Ukraine has led to a short-time renaissance of coal-fired power plants, the age of coal-based power generation is about to end. Nevertheless, the coal-fired power plants no longer needed for their original purpose are still valuable assets. In this paper, we consider three technological approaches for repurposing them: gas-to-power (operation of combined cycle gas turbine plants), power-to-gas (operation of electrolysis plants for feeding hydrogen into the gas grid), and a combination of the two technologies mentioned above. Our aim is to find optimal operating modes in terms of profit for the three approaches. For this, we use a mixed-integer linear multi-variable optimization model and time-resolved price forecasts for electricity and gas for 2030 and 2040. Our results show that, also in future energy systems, gas-to-power plants allow for economic benefits: In times of district heat demand, they operate in the spot market and profit from dual revenues. Balance and ancillary markets allow for additional revenues from the capacity provision. Power-to-gas plants do not show the same good economic performance. However, they allow for an economically sound operation and gain most of their profits in the spot market. Compared to the others, combined plants do not offer economic advantages. In our paper, we also investigate the currently high energy price situation. It allows for payback periods of power-to-gas plants as anticipated for 2040. For this reason, long-term high prices may accelerate the deployment of such future technologies.

Multifaceted land use change and varied responses of ecological carrying capacity: A case study of Chongqing, China

The sustainability of land use is a key issue for ecological conservation; therefore, it is imperative to understand how land use change (LUC) impacts the ecological carrying capacity (ECC). We developed a “direction-speed-pattern” tri-dimensional framework for characterizing LUC and assessed ECC by incorporating the resource provision capacity and environmental support capacity. GTWR model was further employed to examine the impacts of LUC on ECC. Afterwards, an empirical study was conducted in Chongqing city in Southwest China during the period of 2000–2018. The results indicate that the multifaceted LUC exerted spatial-temporally varying impacts on the ECC: (i) Among various LUC directions, afforesting cropland positively affected ECC and this effect was more significant in south-eastern Chongqing, while both encroaching on forest/cropland through urban expansion and converting forests/grass to cropland caused far-reaching negative impacts; (ii) Regarding the relationship between LUC speed and ECC, there was a negative-positive shift in Chongqing from 2010 to 2018; (iii) In terms of LUC pattern, we found various landscape metrics played a significant and heterogeneous role in ECC performance. Accordingly, by synthesizing the lens of direction, speed, and pattern, tailored land use strategies are recommended for Chongqing's ECC improvement, which also provides heuristic experiences for other regions worldwide.

Pendekatan Special Perkebunan Kelapa Sawit terhadap Daya Dukung Lingkungan di Kecamatan Anggaberi Kabupaten Konawe

The objectives of this study were (1) to identify the existing conditions of oil palm plantations in Anggaberi District, Konawe Regency (2) to analyze the condition of the carrying capacity of the environment in Anggaberi District, Konawe Regency (3) to formulate the concept of controlling environmental carrying capacity in Anggaberi District, Konawe Regency . This research was carried out through the stages of research methods including conducting studies on primary data and secondary data, namely the availability of geospatial information on the research area, D3TLH information, in the formulation of the concept of carrying capacity control. Based on the results of spatial identification, it shows that there are 2 villages and 1 sub-district that are the location for developing oil palm plantations in Anggaberi District, namely Andabia Village, Lerehoma Village, Wunduongohi Village, with a total area of 2500 Ha. The results of the analysis of environmental service index performance in Anggaberi District are divided into 5 (five) index classes, namely very low class, low, medium, high and very high class. The average carrying capacity index value of the provision, regulation and support ecosystem services in Konawe Regency, where the provision of environmental services ranges from 2.38 to 3.44 (low - high class), the regulatory environmental service index is in the range of 2.12 to 3.18 (low to medium class) and supporting environmental services index values ranging from 2.55 to 2.95 (low to medium class). In detail, the distribution of the index of carrying capacity for environmental services provision, regulation and support in Anggaberi District. The carrying capacity and carrying capacity of the region are highly dependent on the ability of the ecosystem to produce provision, maintenance and protection services. The ability of ecosystems to produce the services mentioned above is very dependent on the condition/state of the landscape or ecoregion conditions, the condition of the distribution of natural vegetation and the condition of land cover throughout the mainland of Konawe Regency. The combination of these three variables greatly determines the ability of ecosystems to produce services, both provisioning services, regulatory services and protection services.

Storage and demand response contribution to firm capacity: Analysis of the Spanish electricity system

Provision of firm capacity will become a challenge in power systems dominated by renewable generation. This paper analyzes the competitiveness and role of battery storage, six types of pumped-hydro storage, open cycle gas turbine (OCGT), and demand response (DR) technologies in providing the firm capacity required to guarantee the security of supply in a real-size power system such as the Spanish one in horizon 2030. The paper contributes with detailed and realistic modeling of the DR capabilities. Demand is disaggregated by sector and activities and projected towards 2030, applying a growth rate by activity. The load flexibility constraints are considered to ensure the validity of the results. A generation operation planning and expansion model, SPLODER, is conveniently upgraded to properly represent the different storage alternatives addressed in the paper. The results highlight the importance of considering demand response for evaluating long-term firm capacity requirements, showing a non-negligible impact on the investment decisions on the amount of firm capacity required in the system and the optimal shares of wind and solar PV renewable generation. Results also show the dominance of cost-competitiveness of pumped hydro and OCGTs over batteries. Additionally, capacity payments are required to support firm capacity providers’ investments.

PowerMorph: QoS-Aware Server Power Reshaping for Data Center Regulation Service

Adoption of renewable energy in power grids introduces stability challenges in regulating the operation frequency of the electricity grid. Thus, electrical grid operators call for provisioning of frequency regulation services from end-user customers, such as data centers, to help balance the power grid’s stability by dynamically adjusting their energy consumption based on the power grid’s need. As renewable energy adoption grows, the average reward price of frequency regulation services has become much higher than that of the electricity cost. Therefore, there is a great cost incentive for data centers to provide frequency regulation service. Many existing techniques modulating data center power result in significant performance slowdown or provide a low amount of frequency regulation provision. We present PowerMorph , a tight QoS-aware data center power-reshaping framework, which enables commodity servers to provide practical frequency regulation service. The key behind PowerMorph is using “complementary workload” as an additional knob to modulate server power, which provides high provision capacity while satisfying tight QoS constraints of latency-critical workloads. We achieve up to 58% improvement to TCO under common conditions, and in certain cases can even completely eliminate the data center electricity bill and provide a net profit.

Study on the Construction Method and Effects of Ipsilateral, Multi-Nozzle, High-Pressure Jet Grouting Cut-Off Wall

High-pressure jet grouting is widely used in the construction of cut-off wall in hydraulic engineering. Compared to the high-pressure jet grouting used for foundation improvement, the high-pressure jet grouting cut-off wall of hydraulic engineering has lower requirements for the advance consolidation and provision of bearing capacity, and more focus on providing an anti-seepage effect and ensuring the continuous integrity of the wall. In the past, the research on high-pressure jet grouting focused more on the application to foundation treatments, and the research on the construction efficiency of cut-off wall is relatively insufficient. Therefore, in this study, a self-developed ipsilateral multi-nozzle jet grouting machine with a large drill diameter and construction method are proposed according to the construction characteristics of the embankment cut-off wall in hydraulic engineering. Based on the dyke protection projects, Jinggangshan navigation hydropower and Xingan navigation hydropower, the large-diameter, multi-nozzle, high-pressure jet cut-off wall test is carried out, and the wall forming effect of the cut-off wall is verified through the combination of indoor and outdoor tests. The results show that the proposed construction method can adapt to the formation conditions in which it is difficult to implement conventional high-pressure jet grouting, and obtains good construction efficiency. A favorable wall quality can be obtained by using more efficient large-diameter and ipsilateral multi-nozzle jet grouting in the construction of high-pressure jet cut-off wall.

Seasonality in European and North American Air Transport Markets: Network Structures and Implications for Airline Performance and Recovery

Abstract This industry note focuses on the seasonal variability in air traffic services and highlights the differences between air service capacity provision in Europe and North America. We explore the manifestations and measurement of seasonality, looking at the trends across airport communities and among airlines in the two continental regions. The relationship between airline network structure and seasonality is also explored in the study. We argue that there are a complex set of drivers of the observed differences in air traffic seasonality and set out a research agenda for further investigation.