Purchase Cost Research Articles

Reactive power optimization in distribution systems considering load levels for economic benefit maximization

Introduction. The need for electrical energy has been increased sharply due to hasty growth in industrials, social and economic improvements. From the previous studies, it has been agreed that almost 13 % of the total power generated is wasted as heat loss at distribution level. It has been extensively recognized that the node voltage profile along the distribution system can be enhanced under steady state power transfer controlled by proper reactive power compensation. Capacitors have been acknowledged as reactive power compensating device in distribution systems to achieve technical and economical benefits. Novelty of this work is the application of Archimedes optimization algorithm for reactive power optimization in distribution systems so as to obtain an improved solution and also a real 94-bus Portuguese network and modified 12-bus network has been taken and validated for three different load levels which are totally new. Purpose of the proposed work is to maximize the economic benefit by reducing the power loss and capacitor purchase cost at three different load conditions subject to satisfaction of equality and inequality constraints. Methods. The economic benefit has been validated using Archimedes optimization algorithm for three load levels considering three distribution systems. Results. The computational outcomes indicated the competence of the proposed methodology in comparison with the previously published works in power loss minimization, bus voltage enhancement and more economical benefit and proved that the proposed methodology performs well compared to other methods in the literature.

Pareto Optimal Solution of a Fuzzy Newsboy Problem

In this paper, a multi-item classical newsboy problem is formulated, occurring both fuzziness and randomness with floor space constraint. Here, the demand is considered as a random variable in fuzzy sense and also the purchase cost, salvage value, and selling price are fuzzy numbers. Initially, a method is explained for solving such a problem by using the minimization of a FN by Buckley [Buckley, JJ (2003). Fuzzy probabilities: New approach and applications]. Then the fuzzy programming technique, [Formula: see text]-constraint, and the weighted sum methods are applied to handle the multiobjective programming problem. The basic idea for transforming the fuzzy stochastic programming problem into a deterministic equivalent has been discussed. Finally, the deterministic model is solved by the LINGO package and is illustrated numerically.

Low-carbon optimal operation of electricity–heat–gas​ systems based on bi-directional tiered-pricing carbon trading

In the context of carbon peak and carbon neutrality target of China, multi-energy systems have become a key way to meet the needs of a low-carbon economy in the energy sector, and can achieve optimization and integration of multi-energy sources. For the purpose of maximize the low-carbon and economic of multi-energy systems, this paper proposes an optimization operation strategy of electricity–heat–gas integrated energy systems (EHGIES) based on bi-directional tiered-pricing carbon trading. The paper first establishes a multi-energy system model with CHP system and P2G conversion, introduces a bi-directional tiered-pricing carbon trading mechanism. Subsequently, an optimization model with objective function of the lowest carbon trading cost and energy purchase cost is established. The nonlinear optimization model is converted to a linear model by the CPLEX solver. Finally, this paper analyzes the trading mechanism, the interval length of tiered-pricing and carbon trading price on carbon emissions and carbon trading cost of EHGIES. The results show that different carbon trading price ranges and price growth rates have different impacts on carbon emissions and carbon trading costs. At the same time, the bi-directional tiered-pricing carbon trading mechanism established can reduce the overall carbon emissions effectively and is conducive to the low-carbon operation, and the low-carbon and economic nature of system operation can effectively be taken into account.

District Heating System Optimisation: A Three-Phase Thermo-Hydraulic Linear Model

Investments in the development of the district heating system require a thorough analysis of the technical, economic, and legal aspects. Regarding the technical and economic context, a mathematical model of the district heating system has been proposed. It optimizes both the technical and economic aspects of the function and development of a district heating system. To deal with non-linearities, the developed linear programming model is divided into three phases: flow, thermal, and pressure. Therein, non-linear dependencies are calculated between the linear optimization phases. This paper presents the main assumptions and equations that were used to calculate the parameters of the heating system, along with the optimal level of heat production, the flow rate of the heating medium in the heat nodes and edges of the network graph, the heat, power, and temperature losses at each edge, and the purchase costs of heat and its transmission. The operation of the model was tested on a real-world district heating system. The case study results confirm that the model is effective and can be used in decision support. The economic results of the model, before the calibration process, were 3.6% different from historical values. After the calibration process, they were very similar to the real data—all percentage deviations were within 1%.

A Review of the Digitalization of Agriculture in Nigeria

It has become difficult to articulate the impacts, needs and challenges of digitalization of agriculture due to the extensive nature of publications relating to the digitalization of the agricultural sector. This review evaluated the effect of digitalization of agriculture on improved food production and standard of living, identified the training needs of extension staff and clientele for digitalization of agriculture, and highlighted the challenges of digitalization of agriculture. From an initial search of 208 articles, only 87 articles met the inclusion criteria using the PRISMA guidelines. Most articles were published between 2016 and 2020; more studies were carried out in the South Western region of the country. Digitalization of agriculture has reduced the role of middlemen, provided opportunities for farmers to expand their markets, and improved the linkage between extension and research centers, and productivity and livelihood of small-scale farmers. Training needs for effective digitalization of agriculture were in skills, use of relevant digital services, digital privacy and security risks. Challenges of digitalization of agriculture were lack of technical skill, poor infrastructure and high cost of purchase and maintenance. The government should focus on initiating agricultural technology transfer programs and provide the necessary rural infrastructure to support the sector's digitalisation.

A Study of a Two Storage Single Product Inventory System with Ramp Type Demand, N-Phase Prepayment and Purchase for Exigency

This model considers a two-warehouse inventory system of deteriorated items with ramp-type demand and a constant rate of deterioration. It is maintained a rental warehouse (RW) of infinite capacity to load the excess items of replenished goods after filling the items of finite capacity in the own warehouse (OW). Retailers are encouraged to opt for the prepayment option of paying their purchase cost in equal installments prior to the delivery of the ordered items with a considerable discount, which will ensure the purchase guarantee of their orders. The slotted backlog interval of the stock out period is handled in two different ways to retain the customers and ease their impatience. Customers in the first slot of the stock out period are satisfied by the emergency purchases from local suppliers with high purchasing costs to avoid losing customers. Customers in the next slot are satisfied immediately after the next replenishment point. Essential measures of the system are derived: optimal ordering quantities from both regular and local suppliers; replenishment cycle length; and a partitioned backlog interval. A numerical example is given along with the optimal solutions for a particular environment with sensitive analysis in order to validate the model’s efficacy.

Development of a Constant Temperature Hot and Cold-Water Supply System (CT50WS) for Laboratory Application

Over 95% of Nigeria undergraduate students enrolled in public universities. Public universities in Nigeria are however poorly funded and lack adequate facilities. The recent rise in the foreign currency against the Nigerian Naira has further increase the cost of purchasing and maintaining foreign equipment. In this work, a constant temperature hot and cold-water supply system (CT50WS) for laboratory application was developed. This is to explore the production of equipment locally. The developed system was tested on a load and no-load conditions. A shell and tube heat exchanger were used to simulate the load on the component. The system was designed to heat and cool 50 liters of water independently. Results of the tests carried out on the constructed CT50WS on no load condition showed that the actual rate of heat loss from the hot water system is 34.4W. The actual rate of heat gain from the cold-water tank is 16.03W, far lower than the designed heat gain rate of 74.9 W (10%) heat gain rate. When tested on-load condition, the CT50WS was able to continuously supply 100 litre/hr of hot and cold water at a temperature of 50 and 18oC respectively to the heat exchanger. The open market cost of a similar foreign equipment is about 25 times the cost of CT50WS. Its acceptability will further open opportunities in local production of teaching and research equipment, thereby serving as source of job creation and saving the scarce foreign currencies.

MP23-20 A SINGLE CENTER COMPARATIVE STUDY OF TWO SINGLE USE DIGITAL FLEXIBLE URETEROSCOPY IN THE MANAGEMENT OF RENAL STONES LESS THAN 2 CM

You have accessJournal of UrologyCME1 Apr 2023MP23-20 A SINGLE CENTER COMPARATIVE STUDY OF TWO SINGLE USE DIGITAL FLEXIBLE URETEROSCOPY IN THE MANAGEMENT OF RENAL STONES LESS THAN 2 CM Fouad Zanaty, Mohamed Elshazly, Hossam Kandeel, and Baher Salman Fouad ZanatyFouad Zanaty More articles by this author , Mohamed ElshazlyMohamed Elshazly More articles by this author , Hossam KandeelHossam Kandeel More articles by this author , and Baher SalmanBaher Salman More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000003248.20AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: For renal stones <2 cm, guidelines recommend the use of retrograde intrarenal surgery as a first line treatment option. Many available single use flexible ureteroscopy were found. We aim to compare the effectiveness of two single use flexible ureteroscopy; Pusen uscope 3011 versus LithoVue in the management of renal stones less than 2 cm. METHODS: Our study prospectively included 60 patients equally divided in to 2 groups; Pusen group and LithoVue group during the period from June 2020 to June 2021. The included patients were above 18 years old. Perioperative details as operative time, fluoroscopy time, hospital stay and complications were recorded. Stone free rate was assessed. Base purchase cost was also compared. RESULTS: There was no statistically significant difference between the 2 groups regarding age, gender and body mass index (BMI), stones size, side, number and location. The perioperative evaluation and outcome had no statistically significant differences between the 2 groups regarding the operative time, hospital stay, access sheath use, and stone free rate or radiation exposure. Among all cases we had 49 cases (81.6%) with no postoperative complications (21 cases for Pusen group and 28 cases for Lithovue group). The incidence of postoperative complications was significantly higher among Pusen group than lithoVue group (p=0.02). Initial purchase cost for both FURS had no significant difference (p=0.86). CONCLUSIONS: RIRS can be performed effectively with Pusen 3011 and LithoVue single use flexible ureteroscopy in patients diagnosed with renal calculi <2 cm with superior outcomes with LithoVue. Source of Funding: None © 2023 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 209Issue Supplement 4April 2023Page: e314 Advertisement Copyright & Permissions© 2023 by American Urological Association Education and Research, Inc.MetricsAuthor Information Fouad Zanaty More articles by this author Mohamed Elshazly More articles by this author Hossam Kandeel More articles by this author Baher Salman More articles by this author Expand All Advertisement PDF downloadLoading ...

A Note on Recommendation of Cooking Recipes Considering Healthcare

Many recommendation methods for cooking recipes are proposed in previous research. There are many studies on maximizing evaluation score on healthcare, but few studies on maximization under the limits on the cost of purchasing additional ingredients and food loss. In this research new recommendation and purchase methods are proposed. Dynamic programming is applied in the proposed methods. The basic proposed method maximizes the evaluation score on healthcare under the limits on the cost of purchasing additional ingredients and food loss. It is possible that there are multiple optimal solutions. To address this issue, two improvements of the basic proposed method are implemented. The two improved proposed methods minimize the additional purchase cost and the food loss in addition to the maximization of the healthcare score when there are multiple optimal solutions. The minimization of the additional purchase cost takes priority over the minimization of the food loss in the first improved proposed method. The minimization of the food loss takes priority over the minimization of the additional purchase cost in the second improved proposed method. The effectiveness of the proposed methods is shown by some computational examples.

Optimal reactive power pricing with transformer variable taps using genetic algorithm

&lt;span lang="EN-US"&gt;Ancillary services in interconnected networks are crucial to secure real power transfers, maintaining network reliability, improving power quality as well as network stability. Reactive power has always been of special importance as one of the most substantial ancillary services required to control the voltage in power grid. This paper presents a fresh reactive power pricing approach by embedding variable transformer taps into voltage ampere reactive (var) pricing method. To carry out the resultant optimization problem with a set of complicating constraints, the genetic algorithm takes part and guarantees the global optimal solution. The simulation results show that when transformer tap works as a control variable, the total cost of reactive power can be decreased. However, the incorporation of transformer taps in the pricing model can slightly complicates voltage profiles as the sensitivity of bus voltages to the reactive power variations in the system is increased. Further, the findings reiterate that by optimal position of transformer taps, technically, the security index of the system can be enhanced while the var price for end-users (lowest purchase cost for independent system operator) being more reasonable. To simulate the proposed reactive pricing method, the standard IEEE 30-bus system is employed to analyze the proposed method.&lt;/span&gt;

Solve the Problem of Expensive Drugs in Hospitals by Blockchain

Effective treatment of major diseases has always been one of the key research topics for doctors. Some researchers have found that the lack of drugs and the proliferation of counterfeit drugs have a great impact on disease treatment, especially in developing countries. However, there is still a gap in research on drug cost control and hospital official drug pricing. As we all know, blockchain technology has been used in securities trading and other fields to reduce the costs of both parties. Therefore, the research topic of this paper is how to reduce the cost price of drugs purchased by hospitals nationwide or even globally, so that the price of drugs can be reduced to a win-win situation for hospital patients. The structure of this article is as follows: First, it introduces the current status of the application of blockchain technology at home and abroad, so that people can more clearly understand which transactions around them have used this technology. Later, this article will describe the working mechanism of blockchain technology, and finally introduce how to use this technology in drug trading. Through research, it is found that the point-to-point transaction of blockchain technology can greatly reduce the cost and time for hospitals to purchase drugs, reduce the price of expensive drugs in hospitals, enable more patients to get effective and rapid treatment of diseases, and reduce the phenomenon of family decline caused by illness. This shows that the effective reduction of drug purchase costs through blockchain technology is conducive to overcoming the problems of diseases and maintaining the stable income of hospitals.

Management and control optimization based on deep learning model

Microgrid technology is a key solution to improve distributed power consumption, complementary utilization of multiple energy sources, and power supply reliability. To guarantee the reliability of the microgrid system, a realistic strategy must be created. This work takes the microgrid as an object and uses simulation technology to construct a microgrid system. Then, using this simulation system and the double deep Q-learning, the goal is to minimize the 24-hour electricity consumption cost from the external power grid to meet the requirements of voltage deviation. Power balancing and energy storage loads for microgrid systems. Under the constraints of the electrical state and other constraints, the control variable is the energy storage's capacity for charging and discharging, and the optimization strategy of energy storage control is obtained through training. The results demonstrate that the DDQN algorithm will save 26.95% of the electricity purchase cost, which is significantly more than the MPPT algorithm's 12.43% savings. As a result, this work examines the efficacy of the charging and releasing approach for energy storage and confirms the potential of the suggested approach to reduce the cost of purchasing electricity.

Optimal pricing and sourcing strategies in a symbiotic supply chain under supply uncertainty

Uncertainty around the amount of recycled material is common in symbiotic supply chains. However, there are few studies in the field of operational decision-making that focus on this uncertainty. Considering the uncertainty and supply-side competition in a symbiotic supply chain, this paper focuses on decision-making among symbiotic supply chain stakeholders. We derive the analytical forms of the equilibrium solution for order quantities and the wholesale prices of recycled materials. By comparing different decisions, we obtain the conditions for various degrees of symbiosis. In general, a partial symbiosis mode is incurred when the effective purchase cost of recycled materials is higher than that of raw materials. Otherwise, a complete symbiosis mode occurred. Furthermore, the research results show that the decisions of all stakeholders in the symbiotic supply chain are influenced by a union of internal and external enterprise factors. In the partial symbiosis model, the decisions of all parties are influenced by a combination of technical and market factors, while in the complete symbiosis model, the decision-making of all parties is influenced only by a threshold formed by the above factors. In addition, the impact exerted by government policies (subsidies or taxes) on the symbiotic supply chain is studied through numerical experiments. The results of these experiments show that infrastructure subsidies are effective in certain scenarios. In some cases, the waste extraction cost subsidy is effective, while in other cases, the waste disposal tax increases the waste utilized.

Charging Forward: Investigating Consumer Attitudes and Perceptions on Electric Vehicles

The adoption of electric vehicles (EVs) is a crucial step towards achieving sustainable transportation. However, the success of EVs is heavily dependent on the consumers' perception and acceptance of this technology. This paper presents a systematic review of research articles published on the topic of consumer perception of electric vehicles. The review includes articles published between 2015 and 2021 and encompasses a wide range of perspectives, including consumer attitudes, preferences, and barriers to adoption. The findings suggest that consumers have positive perceptions of EVs in terms of environmental benefits, but also express concerns regarding the range, charging infrastructure, and higher purchase cost. Additionally, several studies have found that socio-demographic factors, such as income, age, and education, play a significant role in shaping consumer perceptions of EVs. This paper provides valuable insights into the current state of research on consumer perception of EVs and highlights areas for future research. The results of this review can be useful for policymakers, manufacturers, and other stakeholders in developing effective strategies to promote the adoption of EVs.

Mechanism for loading wheelchairs in the car – a review of technical solutions and a new concept

. One of the main difficulties for wheelchair users is the change of transportation mode, such as from a wheelchair to a car, and especially the subsequent loading the wheelchair to or unloading from the car. The rapid development of mechanics and mechatronics in numerous industries is also being recognised in the transportation industry dedicated for people with motor disabilities. The article presents an overview of solutions to assist in loading or unloading a wheelchair from a car. The latest solutions available on the market and among those under patent protection were demonstrated. Prominent structures include lifts and cranes. The available solutions may differ in terms of: the level of muscle power use, the energy intensity of the loading process, the occupied space in the car, the convenience of loading and unloading, the need for third-party assistance, versatility in mounting to the car, purchase cost, weight, etc. The aim of the review presented here is to raise awareness in terms of choosing a device that assists in loading a wheelchair to and unloading from a car.

Wychowawcza rola orkiestr szkolnych w gimnazjach autonomicznej Galicji

Orchestras existed in most high schools. They were composed of either wind or string instruments but rarely were they mixed. Sometimes interest circles of music lovers or mandolin players cooperated with the orchestras. In general, the activity of the orchestras developed successfully. The students were actively interested in music and developed their skills in the orchestra. In most cases, they were hampered by financial issues related to the cost of purchasing and maintaining their instruments. The orchestras were supervised by teachers, professors, and sometimes professional musicians who had enthusiasm for this kind of work, but often worked for small fees. The orchestras mostly performed during school celebrations. In practically all the junior high schools, they performed separate soirées in honor of each of the Three Bards (Adam Mickiewicz, Juliusz Słowacki, and Zygmunt Krasiński). Other celebratory performances included the following themes: the anniversaries of the November and January Uprisings, the May 3rd Constitution, anniversaries of the reign of the Habsburg dynasty, anniversaries of the death or birthday of Maria Konopnicka, Piotr Skarga, Reverand Jozef Poniatowski, and the anniversaries of Polish victories at Vienna, or Grunwald, and other events important to national history. School orchestras also played in student marches and parades, during games, excursions, and religious events. Additionally, they often played during events for the wider public by participating in official ceremonies, festivals, and picnics. For this reason, they garnered public sympathy and social support which was very important, especially when buying instruments. The orchestras had a powerful influence on the students’ interests in music because being part of the orchestras taught them sensitivity to aesthetics and beauty. Their participation in the ceremonies related to the cultivation of national traditions and customs contributed to the formation of patriotic feelings among the students.

Distributed hierarchical economic optimization approach of microgrid based on multi-agent leader-following consensus

Considering the higher generation operation cost of distributed generations (DGs) and power purchase cost in microgrid, the discrete-time mean consensus protocol (DMCP) is improved by bringing in the power offset elimination term in this paper. Then an improved multi-agent leader-following consensus algorithm (IMLCA) is proposed. The total power balance can be realized by the algorithm, which make the incremental cost (IC) of DGs converge to the consensus value quickly. Besides, the active power output objective of DGs is optimized and the overall generation operation cost of the AC microgrid is lessened. Afterwards, the distributed hierarchical economic optimization approach of microgrid based on multi-agent leader-following consensus is studied. In this approach, a distributed hierarchical framework is constructed. The economic optimization management level emits the optimal active power output objective of DGs to the droop control level. Meantime, the optimal active power output objective computed by IMLCA is carried out by using the droop control level. Thus, the active power output of DGs is apportioned reasonably. Finally, the simulation model of five-DG operation is constructed for research. The simulation results suggest that the approach can achieve the economic cost optimization goal of the grid-connected microgrid and the IMLCA possesses the better transient response performance and steady-state computation accuracy.

The Impact of Price Perception and Brand Image on Attitudinal Loyalty of Innisfree Skincare Consumers

Price perception and brand image are considered as two prominent factors that influence..consumers..intention..to..buy…a skincare. However, those factors do not guarantee consumers’ commitment to a brand. Makes the Innisfree as the research context, researchers want to study whether price..perception..and..brand..image..affect attitudinal loyalty. This research reconstructs the research model of Adawiah (2015) by adding attitudinal loyalty as an endogenous construct and using price perception and brand image as an exogenous construct. The object of this study is Innisfree Skincare. Data..was..collected..by.distributing.google forms.to 150 respondents using purposive sampling. The..data..analysis..technique used..is..Structural.Equation.Modeling.with WarpPLS.7.0. Research shows that..price.perception..and...brand….image have a positive and significant effect on the attitudinal loyalty of Innisfree consumers. Companies are advised to reduce purchase costs, add variants for acne-prone skin, and increase Innisfree’s…advantage….over competitors. Researchers are advised to discuss the effect of..price.perception..on brand..image..and add behavioral loyalty as an endogenous construct.

Computer Assisted Audit Tools and Techniques Adoption: A Systematic Literature Review

Computer Assisted Audit Techniques and Tools (CAATTs) are a form of innovation in the field of technology in the world of accounting, CAATTs have become fundamental in many audit methodologies. However, there is still very little information regarding these CAATTs. This research is based on increasing knowledge about the success of CAATTs, this is useful for analyzing implementation and operational problems with a broader understanding of the practices contained in internal audit departments that use CAATTs technology. Therefore, we present a systematic literature review on the factors that determine an auditee to use CAATTs technology. This research was conducted using a qualitative analysis of the things that influence an audit to use CAATTs in the auditing process based on previous studies. The findings from this study indicate that what influences an audit to use CAATTs is time efficiency, work effectiveness, auditor confidence, company partners, processing accuracy, techniques and services, purchase costs, understanding of using CAATTs, background of the audit itself, motivation to learning, performance expectations, characteristics of the audit team, support or coercion, and facilities.

Two-Stage Participation of Grid-Connected Energy Hubs in Day-Ahead and Real-Time Energy Markets Based on Robust Modeling of Uncertainties

Optimal management of sources, storage, and responsive loads in the energy network leads to improvement of economic and technical situation of the network. However, note that single-layer energy management requires to provide the network operator with more amounts of information. This results in the increase in the processing speed for the network operator. Also, coordination of sources, storage, and responsive loads in the form of an aggregator such as an energy hub can play an important role for them in promoting the economic situation and energy efficiency. So, this paper presents the participation of grid-connected energy hubs (EHs) in the day-ahead (DA) and real-time (RT) energy markets. Scheme has a two-stage optimization framework. In the first stage, participation of EHs in the hourly DA energy market is executed based on a two-layer energy management system that is modeled as bilevel problem. EH model in DA market is formulated in upper-level problem aimed at maximizing their profit subject to meeting the linearized constraints of the EH’s operation. Lower-level problem deals with the operation of energy networks to minimize cost of energy purchase from the upstream network constrained to linearized optimal power flow equations. The second stage of participation of EHs in a 5 min RT market has an objective function to minimize the unbalance between the EHs’ profits in the mentioned two markets. This stage is subject to the upper-level constraints and the lower-level formulation in the first stage. Robust optimization models the uncertainties of load, renewable power, energy price, and energy demand of mobile storage to achieve an optimal robust solution. Benders decomposition algorithm solves bilevel formulation in two-stage scheme. Numerical results confirm capabilities of the scheme in enhancing operation status of the networks and economic situation of EHs. Hence, the Benders decomposition algorithm is able to extract the optimal solution in shorter computation time. Two-layer energy management needs shorter computation time than the single-layer management. Simultaneous modeling of two real-time and day-ahead energy markets reduces the unbalance cost between these markets. The proposed scheme can enhance the operating and economic indicators of the network by up to around 18% and 26% compared to power flow studies of energy networks.