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Objective: To determine the effect of lifetime maxillofacial changes on dental implants placed in adults, analyze the clinical implications of these changes, identify prognostic factors, and offer possible solutions. Overview: The relationship between implant placement and maxillofacial changes, occurring during not only the active growth period but also the entire span of adulthood, has not been extensively examined. Vertical differences between implants and adjacent teeth due to the ankylotic behavior of the former might be observed at any age and endanger restoration biologically, functionally, and esthetically. Regarding interproximal contacts, firm contact loss may occur within a few months after restoration, resulting in food impaction. Many prognostic factors have been reported, but most do not exhibit a statistically significant association with implant infraocclusion and interproximal contact loss. Incorporation of alternative solutions, accurate treatment planning, strict recall protocols, and retrievability of implant‐supported restorations can facilitate efficient management of complications. Conclusion: Maxillomandibular changes throughout adulthood may lead to complications such as implant infraocclusion and interproximal contact loss. Rehabilitation of edentulism should be characterized by well‐designed and flexible treatment plans to resolve long‐term complications efficiently. Further long‐term clinical studies are needed to identify other risk factors. Clinical Significance: Treatment plans for implant therapy should be reconsidered for adults. Careful patient monitoring and early intervention are essential for securing treatment outcomes. [ABSTRACT FROM AUTHOR]

ABSTRACT Objective Materials and Methods Results Conclusions Clinical Significance The aim of the present study was to investigate the relation of the implant position to the implant crown and analyze the location and magnitude of bite force.The dimensions of 49 posterior implant‐supported restorations were recorded in terms of: 1. implant diameter, 2. crown length, 3. crown width, 4. crown height, 5. occlusal surface of the restoration. The crown/implant height was measured and the distance between the implant center and the restoration center revealed the size of intra‐coronal cantilevers. The occlusal force analysis determined the point and magnitude of loading. Correlation coefficient r was used for the statistical process and statistical control was carried out with the aid of t‐test with minimum level of significance p < 0.05. ‐ The mean crown‐to‐implant ratio was 0.9 and in short implants (< 10mm) the ratio was 1.28. ‐ Intra‐coronal cantilever extensions ranged from 2.1 mm to 6.35 mm depending on crown size. ‐ Occlusal loading was identified in cantilever areas of the crown. The mean crown‐to‐implant ratio was 0.9 and in short implants (< 10mm) the ratio was 1.28.Intra‐coronal cantilever extensions ranged from 2.1 mm to 6.35 mm depending on crown size.Occlusal loading was identified in cantilever areas of the crown. ‐ Implant center deviates from crown center in 71%–82% of the cases depending on site location. ‐ Implants with non‐ideal position may support a functionally occluding crown. Implant center deviates from crown center in 71%–82% of the cases depending on site location.Implants with non‐ideal position may support a functionally occluding crown.Intra‐coronal cantilevers are a critical factor to avoid clinical complications and should be taken under consideration both in the planning and fabrication phase of implant restorations. [ABSTRACT FROM AUTHOR]

The emergence of high penetration of renewable energy sources in the energy mix of power systems has substantially increased the need for faster-ramping resources participating in the frequency regulation service procured via market mechanisms by the system operators. However, current market mechanisms do not properly align the incentives for participation since resources are not compensated for the actual frequency regulation they provide nor for the accuracy with which they follow the automatic generation control (AGC) dispatch signal. In this paper, we evaluate the current mechanisms for procuring, dispatching and compensating resources for the frequency regulation service. We also propose a comprehensive approach for calculating the performance payment that includes the actual service they provide and the accuracy with which they follow the AGC signal. Finally, we perform a study by deploying actual operational AGC data for analyzing the proposed methodology. [ABSTRACT FROM PUBLISHER]

Provides information on a study which focused on the competitive procurement of Ancillary Services by an Independent System Operator (ISO). Procurement of Ancillary Services; Discussion on electric power reserves auction; Market power and regulation; Conclusion of the study.

Discusses the characteristics of reactive power that must be considered in order to develop a framework for reactive power pricing and management. Technical and economic issues of the reactive power service; Requirement concept of reactive power; Methods of reactive power pricing; Pricing structure based on local reactive power markets; Conclusions.

• Produce DLMP for all phases/nodes of the distribution grid down to feeder level. • Test on an actual large-scale system without approximations and loss of optimality. • Design a DAM and a RTM to enable the optimization of offers and bids by DERs. • Implement a MIP SCUC and a SCED integrated with an unbalanced three-phased DPF. • Coordinate DSO/TSO markets in a multi-level hierarchical energy market design. In this paper we propose a market design for implementing organized nodal electricity markets for the distribution grid. Distribution System Operators (DSOs) are expected to manage a massive penetration of Distributed Energy Resources (DERs), such as Renewable Energy Resources (RES), Electric Vehicles (EVs), Storage and Demand response. A Day Ahead Market (DAM) and a Real-Time Market (RTM) is proposed to optimize and clear offers and bids submitted by the DERs. A Mixed Integer Programming (MIP) Security Constrained Unit Commitment (SCUC) and a Security Constrained Economic Dispatch (SCED) iterates with a detailed asymmetric and unbalanced three-phased Distribution Power Flow (DPF) to enforce all constraints in the distribution grid. The solution produces Distribution Locational Marginal Prices (DLMPs) for all phases at every node of the distribution grid. A general framework for the coordination of the DSO with the ISO/TSO markets is also presented as an integral part of the proposed multi-level energy market design. The proposed new methodology has been applied to an actual large-scale distribution system. Numerous simulation scenarios have been executed to prove the validity of the proposed approach. In this paper a simple small subset of the actual distribution system is selected to illustrate the proposed methodology. [ABSTRACT FROM AUTHOR]

Electricity price forecasting (EPF) has become an essential part of decision-making for energy companies to participate in power markets. As the energy mix becomes more uncertain and stochastic, this process has also become important for industrial companies, as their production schedules are greatly impacted by energy costs. Although various approaches have been tested with varying degrees of success, this study focuses on predicting day-ahead market (DAM) prices in different European markets and how this directly affects the optimal production scheduling for various industrial loads. We propose a fuzzy-based architecture that incorporates the results of two forecasting algorithms; a random forest (RF) and a long short-term memory (LSTM). To enhance the accuracy of the proposed model for a specific country, electricity market data from neighboring countries are also included. The developed DAM price forecaster can then be utilized by energy-intensive industries to optimize their production processes to reduce energy costs and improve energy-efficiency. Specifically, the tool is important for industries with multi-site production facilities in neighboring countries, which could reschedule the production processes depending on the forecasted electricity market price. [ABSTRACT FROM AUTHOR]

Studies the management of costs associated with transmission constraints in a competitive electricity market. Examination of the two approaches for dealing with these costs; Basis of the first approach and second approach; Provision of an analysis of the proposed financial instruments; Explanation of the basis for this model.

In practice, locational marginal prices (LMPs) are usually calculated by assembling their three components: the reference price, the congestion price, and the loss price. Explicit formulas for calculating the three components based on the single-slack power-flow formulation can be found in the literature. This letter presents the formulas for calculating the three components based on a distributed-slack power-flow formulation. [ABSTRACT FROM AUTHOR]

The stated aim of the European Commission has been the unbounded flow of energy across Europe and the effective functioning of a single European power market so as to achieve secure, sustainable and affordable energy supplies, as well as to foster competition and increase the utilization of electricity networks and generation capacity. Most countries have already adapted or are gradually adapting their wholesale markets to the provisions of the so called Target Model for the internal electricity market in Europe, however Greece still lies behind in this binding target. In this paper, the basic design variables and respective options for the integration of the Greek wholesale electricity market with the other European markets under the Target Model paradigm are presented. The design variables refer to all market instances and mechanisms. The proposed choices are justified in terms of effectiveness and market power mitigation, considering the current market structure in Greece. A transitional phase for the full integration of the Greek Intraday and Balancing Markets is proposed, considering the relevant evolutions in the wholesale markets of Greece’s neighboring countries. Finally, a simulation analysis is performed in order to highlight the implications on schedules of utilizing European-based order formats in the restructured Greek electricity market. [ABSTRACT FROM AUTHOR]

In centralized day-ahead electricity markets with marginal pricing, unit commitment costs and capacity constraints give rise to non-convexities which may result in losses to some of the participating generating units. To compensate them for these losses, a recovery mechanism is required. In Part I of this two-part paper, we present certain recovery mechanisms that result in recovery payments after the market is cleared. We also propose a methodology for evaluating the bidding strategy behavior of the participating units for each mechanism. In this paper (Part II), we apply this methodology to evaluate the performance and incentive compatibility properties of each recovery mechanism on a test case model representing the Greek joint energy/reserve day-ahead electricity market. Lastly, we perform sensitivity analysis with respect to key parameters and assumptions and we provide directions for further research. [ABSTRACT FROM PUBLISHER]

In centralized day-ahead electricity markets with marginal pricing, unit commitment costs and capacity constraints give rise to non-convexities which may result in losses to some of the participating generating units. Therefore, a recovery mechanism is required to compensate them. In this paper, we present and analyze several recovery mechanisms that result in recovery payments after the market is cleared. Each of these mechanisms results in a different type and/or amount of payments for each participating unit that exhibits losses. We also propose a methodology for evaluating the bidding strategy behavior of the participating units for each mechanism. This methodology is based on the execution of a numerical procedure aimed at finding joint optimal bidding strategies of the profit-maximizing units. In a companion follow-up paper (Part II), we apply this methodology to evaluate the performance and incentive compatibility of the suggested recovery mechanisms on a simplified test case model of the Greek electricity market. [ABSTRACT FROM PUBLISHER]

A detailed AC OPF-based formulation for procuring, pricing, and settling energy and ancillay service in simultaneous auctions by integrated market systems is presented. The paper provides clear definitions of locational marginal prices for energy and ancillary service marginal prices in terms of Lagrange multipliers. The characteristics of the prices are analyzed especially when economic substitution among ancillary services is required. The paper also evaluates the conditions under which opportunity costs are incurred to units that provide ancillary services. It is particularly shown that the intuitive belief that the provision of regulation down service does not incur opportunity cost to the provider, in general, is not true. [ABSTRACT FROM AUTHOR]

Presents a methodology for calculating optimal generation schedules that minimize energy payments by power pool consumers. Issues addressed related to market structure and power pool operation; Integration of the generator scheduling periods in the evaluation process; Formulation of the Consumer Payment Minimization problem.