Gotowa bibliografia na temat „Fixed Waiting Costs”

Understanding mechanism of users in responding determinant variables to use mode of transport is beneficial to anticipate the effect of policy. This study aims to identify the elasticity value of travel time and travel cost of the users of private vehicles and public transportation. Using data from users of private vehicles and public transport in Bandung, Indonesia, the elasticity of travel time and travel cost was calculated based on estimated multinomial logit model (MNL) logit. The elasticity was calculated based on gasoline prices, parking fees, transfer fees, access times, travel times, and waiting times. Based on the results of the elasticity values for travel attribute, it was found that in access time and travel time, Trans Metro Bandung (TMB) Bus had the largest elasticity of -0,564 and -5,001, respectively, so TMB Bus was the most sensitive to changes in access time and travel time. In terms of waiting times and fixed costs/gasoline, conventional taxi has the highest elasticity values of -2,630 and -1,604, respectively, so conventional taxi is the most sensitive to changes in waiting time and fixed costs/gasoline.

Background: Continuous oral targeted therapies (OTT) represent a major economic burden on the Canadian healthcare system, due to their high cost and administration until disease progression/toxicity. The recent introduction of venetoclax-based fixed-duration combination therapies has the potential to reduce such costs. This study aims to estimate the prevalence and the cost of CLL in Canada with the introduction of fixed OTT. Methods: A state transition Markov model was developed and included five health states: watchful waiting, first-line treatment, relapsed/refractory treatment, and death. The number of CLL patients and total cost associated with CLL management in Canada for both continuous- and fixed-treatment-duration OTT were projected from 2020 to 2025. Costs included drug acquisition, follow-up/monitoring, adverse event, and palliative care. Results: The CLL prevalence in Canada is projected to increase from 15,512 to 19,517 between 2020 and 2025. Annual costs were projected at C$880.7 and C$703.1 million in 2025, for continuous and fixed OTT scenarios, respectively. Correspondingly, fixed OTT would provide a total cost reduction of C$213.8 million (5.94%) from 2020 to 2025, compared to continuous OTT. Conclusions: Fixed OTT is expected to result in major reductions in cost burden over the 5-year projection, compared to continuous OTT.

Before shared automated vehicles (SAVs) can be widely adopted, they are anticipated to be implemented commercially in confined regions or fixed routes where the benefits of automation can be realized. SAVs have the potential to operate in a traditional transit corridor, replacing conventional transit vehicles, and have frequent interactions with riders and other vehicles sharing the same right of way. This paper microsimulates SAVs’ operation on a 6.5-mile corridor to understand how vehicle size and attributes of such SAV-based transit affect traffic, transit riders, and system costs. The SUMO (Simulation of Urban MObility) platform is employed to model microscopic interactions among SAVs, transit passengers, and other traffic. Results show that the use of smaller, but more frequent, SAVs leads to reduced passenger waiting times but increased vehicle travel times. More frequent services of smaller SAVs do not, in general, significantly affect general traffic due to shorter dwell times. Overall, using smaller SAVs instead of the large 40-seat SAVs can reduce system costs by up to 4% while also reducing passenger waiting times, under various demand levels and passenger loading factors. However, the use of 5-seat SAVs does not always have the lowest system costs.

In today's competitive environment, having the best sequence of operations for production and distribution activities is a basic need for survival. As a result, one of the major challenges in fixed supply chain systems is unnecessary transportation costs and the inability to meet customer demand as quickly as possible. In order to meet these challenges, factories and mobile equipment have been considered in this study, and have recently been used in several industries, including pharmaceutical, chemical, and dairy. In the course of this study, a novel mathematical model was put forward for an integrated production and distribution scheduling problem taking into account some real-world features, focusing on reducing customer waiting time and also reducing production costs. A small-scale problem was resolved to check the model’s accuracy. The accuracy of the model is affirmed given the example and its solution acquired from GAMS software. The results of the study prove the effectiveness of this model in reducing customer waiting time and production costs and also demonstrate that the model has the capacity to be utilized by all organizations that produce and distribute perishable products, including dairy and pharmaceutical products, chemical compounds and masks during the Coronavirus pandemic.

We study the multiserver queue with Poisson arrivals and identical independent servers with exponentially distributed service times. Customers arriving at the system are admitted or rejected according to a fixed threshold policy. Moreover, the system is subject to holding, waiting, and rejection costs. We give a closed-form expression for the average costs and the value function for this multiserver queue. The result will then be used in a single step of policy iteration in the model where a controller has to route to several finite-buffer queues with multiple servers. We numerically show that the improved policy has a close to optimal value.

We study the multiserver queue with Poisson arrivals and identical independent servers with exponentially distributed service times. Customers arriving at the system are admitted or rejected according to a fixed threshold policy. Moreover, the system is subject to holding, waiting, and rejection costs. We give a closed-form expression for the average costs and the value function for this multiserver queue. The result will then be used in a single step of policy iteration in the model where a controller has to route to several finite-buffer queues with multiple servers. We numerically show that the improved policy has a close to optimal value.

Firm size has been empirically found to be strongly positively related to capital structure. This paper investigates whether a dynamic capital structure model can explain the cross-sectional size–leverage relationship. The driving force that we consider is the presence of fixed costs of external financing that lead to infrequent restructuring and create a wedge between small and large firms. We find four firm-size effects on leverage. Small firms choose higher leverage at the moment of refinancing to compensate for less frequent rebalancings. Their longer waiting times between refinancings lead to lower levels of leverage at the end of restructuring periods. Within one refinancing cycle, the intertemporal relationship between leverage and firm size is negative. Finally, there is a mass of firms opting for no leverage. The analysis of dynamic economy demonstrates that in cross-section, the relationship between leverage and size is positive and thus fixed costs of financing contribute to the explanation of the stylized size–leverage relationship. However, the relationship changes sign when we control for the presence of unlevered firms.

Abstract Multimodal transportation is getting more and more attention due to its economical and efficient characteristics. Choosing a reasonable transportation plan can effectively control transportation costs. Considering that there are fixed schedules for railway and waterway transportation in real life, this article will establish a multimodal transportation route optimization model with the goal of minimizing the total transportation cost consisting of transportation cost, transit cost, waiting cost and carbon emission cost. The genetic algorithm based on preservation strategy and immigration strategy is used to solve the model. The effectiveness of the model is proved by the case study, and it can provide decision support for the choice of multimodal transportation scheme.

Problem definition: We study a dynamic market over a finite horizon for a single product or service in which buyers with private valuations and sellers with private supply costs arrive following Poisson processes. A single market-making intermediary decides dynamically on the ask and bid prices that will be posted to buyers and sellers, respectively, and on the matching decisions after buyers and sellers agree to buy and sell. Buyers and sellers can wait strategically for better prices after they arrive. Academic/practical relevance: This problem is motivated by the emerging sharing economy and directly speaks to the core of operations management that is about matching supply with demand. Methodology: The dynamic, stochastic, and game-theoretic nature makes the problem intractable. We employ the mechanism-design methodology to establish a tractable upper bound on the optimal profit, which motivates a simple heuristic policy. Results: Our heuristic policy is: fixed ask and bid prices plus price adjustments as compensation for waiting costs, in conjunction with the greedy matching policy on a first-come-first-served basis. These fixed base prices balance demand and supply in expectation and can be computed efficiently. The waiting-compensated price processes are time-dependent and tend to have opposite trends at the beginning and end of the horizon. Under this heuristic policy, forward-looking buyers and sellers behave myopically. This policy is shown to be asymptotically optimal. Managerial implications: Our results suggest that the intermediary might not lose much optimality by maintaining stable prices unless the underlying market conditions have significantly changed, not to mention that frequent surge pricing may antagonize riders and induce riders and drivers to behave strategically in ways that are hard to account for with traditional pricing models.

The problem of determining the optimal selling price and lot size for an inventory system with non-instantaneous deteriorating item is considered in this chapter. In order to provide general framework, the pricing and lot sizing problem is modeled assuming a general price and time dependent demand function. The model allows for backlogging of demand which is characterized by decreasing function of waiting time. As the problem involves revenue and costs, a natural objective function for the model is profit per period. First, the sub problem in which price is fixed is solved to determine the optimal inventory policy. To broaden the problem, a procedure is developed for obtaining the optimal selling price and order size. To investigate the characteristics of the proposed model, numerical illustrations are presented.

For the past 100 years, film has been almost the exclusive medium for capturing, storing, and displaying radiographic images. Film is a fixed medium with usually only one set of images available. Today, the radiologic sciences are on the brink of a new age. In particular, Picture Archiving and Communication System (PACS) technology allows for a near filmless process with all of the flexibility of digital systems. PACS consists of image acquisition devices, storage archiving units, display stations, computer processors, and database management systems. These components are integrated by a communications network system. Filmless radiology is a method of digitizing traditional films into electronic files that can be viewed and saved on a computer. This technology generates clearer and easier-to-read images, allowing the patient the chance of a faster evaluation and diagnosis. The time saved may prove to be a crucial element in facilitating the patient’s treatment process. With filmless radiology, images taken from various medical sources can be manipulated to enhance resolution, increasing the clarity of the image. Images can also be transferred internally within hospital departments and externally to other locations such as the office of the patient’s doctor or medical specialist in other parts of the world. This is made possible through the picture-archiving and communication system (Dreyer, Mehta, & Thrall, 2001), which electronically captures, transmits, displays, and saves images into digital archives for use at any given time. The PACS functions as a state-of-the-art repository for long-term archiving of digital images, and includes the backup and bandwidth to safeguard uninterrupted network availability. The objective of the picture-archiving and communications system is to improve the speed and quality of clinical care by streamlining radiological service and consultation. With instant access to images from virtually anywhere, hospital doctors and clinicians can improve their work processes and speed up the delivery of patient care. Besides making film a thing of the past, the likely benefits would include reduced waiting times for images and reports, and the augmented ability of clinicians since they can get patient information and act upon it much more quickly. It also removes all the costs associated with hard film and releases valuable space currently used for storage. According to Dr. Lillian Leong, Chairman of the Radiology IT Steering Group of the Hong Kong Medical Authroity, a single hospital can typically save up to 2.5 million Hong Kong dollars (approximately US$321,000) a year in film processing cost (Intel, 2007). The growing importance of PACS on the fight against highly infectious disease such as Severe Acute Respiratory Syndrome (SARS) is also identified (Zhang & Xue, 2003). In Hong Kong, there was no PACS-related project until the establishment of Tseung Kwan O Hospital (TKOH) in 1998. The TKOH is a 600-bed acute hospital with a hospital PACS installed for the provision of filmless radiological service. The design and management of the PACS for patient care was discussed in the first edition of this encyclopedia (Tong & Wong, 2005). The TKOH was opened in 1999 with PACS installed. At the beginning, due to immature PACS technologies, the radiology service was operating with film printing. A major upgrade was done in 2003 for the implementation of server clustering, network resilience, liquid crystal display (LCD), smart card, and storage-area-network (SAN) technologies. This upgrade has greatly improved the reliability of the system. Since November 2003, TKOH has started filmless radiology service for the whole hospital. It has become one of the first filmless hospitals in the Greater China region (Seto, Tsang, Yung, Ching, Ng, & Ho, 2003; Tsou, Goh, Kaw, & Chee, 2003).

Abstract The number of decommissioning activities in the offshore wind industry will increase in the coming years as many wind turbines reach their planned service lifetimes. Cost-effective solutions for decommissioning are important considering the levelized cost of energy of offshore wind farms. In addition to the existing challenges in marine operations such as waiting for suitable weather window, logistics and availability of the vessels, the limited experience in offshore wind decommissioning makes the process more challenging regarding the fact that the size of current installations of offshore wind turbines is growing considerably and more preparation and competence are required in association with new projects. In this paper, a review of existing decommissioning methods for offshore bottom-fixed wind turbines is provided first. The removal of wind turbines’ foundation and transition piece, on which significant duration of decommissioning operation is spent, is identified as a critical element, and is focused on. The decommissioning challenges and the decommissioning techniques implemented in previous projects are studied. These include partial and complete removals of foundations. These techniques and methods will be investigated thoroughly.

Possible changes to F404 turbofan engine test procedures have been investigated to reduce cost and time. The current procedures specify either fixed waiting times or stable conditions before acquiring data for performance checks. These stabilization times can account for several thousand litres of fuel. A literature-supported, experimental study is described to quantify stabilized operation. A set of derived stabilization indices are compared to measured data. Possible reductions in single tests ranged from 30 to 200 seconds. Variations are presented resulting from ambient conditions, and the extent of throttle movement Fuel savings of 300 to 700 litres are estimated depending on the maintenance test and are projected to about $100K on an annual, fleet-wide basis. Heat transfer modelling and validation issues are also discussed.

The waterway is the necessary passage for ships to enter and leave the port. From the perspective of cost, many coastal port channels are one-way channels, it alternates as an inbound channel and an outbound channel. The oneway channel conversion strategy refers to when it is used as an inbound channel and when it is used as an outbound channel. By constructing a simulation model, this paper simulates the one-way channel conversion strategy that uses a fixed time period conversion, a conversion considering a certain number of outbound ships, and a conversion with the combination of time and number of outbound ships to achieve the best state of the port's overall operations. By comparing the port service level, traffic capacity of waterway, ships waiting time and other indicators, a one-way channel conversion strategy suitable for port operations is recommended.