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1.
Cross‐docking replaces traditional warehousing, enabling continuous flow of items without storage. Here we model location‐distribution networks, that include cross‐docking facilities, to obtain the latter's impact on the supply chain. We formulate optimization models to minimize total cost in three multi‐echelon networks, each model generalizing the preceding one. The first includes a single manufacturer, one product type, and multiple customers. Cross‐docks are to be located between origin and destinations. Besides solving optimally, a tool for quantitative analysis of direct‐shipment decisions is developed. The second model considers more than one product: We determine a cost‐effective sequence of items for indirect shipment (via cross‐docks). Finally, in a network with multiple origins, optimal solutions are obtained for 40 medium‐sized and larger examples.  相似文献   
2.
Construction project scheduling is one of the most critical factors for project success measurement.Not only for the project planning but for construction process management,the scheduling is the basic tool for communication between the owner and the project manager.By developing the schedule before the project starts,the owner knows in advance that the expected timeline of the project.By preparing construction process scheduling,the owner and general contractor can better manage the subcontractors,sub-trades progress,materials storage and deliveries,labors schedule and equipment set up which will eventually save time,money and hassle.Basically,Critical Path Method(CPM) is commonly used in the construction industry.CPM is a deterministic method that assumes that through the network,there is at least one path that determines the project duration and that the path is the critical path.CPM does not consider the uncertainty in the activities;rather it assumes that each activity can be finished in the given situation.Program Evaluation and Review Technique(PERT) is a stochastic technique which is based on the assumption that the duration of a single activity can be described by a probability density function.PERT takes into account the uncertainty during the construction process and has been created out of the need to plan,schedule and control complex projects with many uncertainties.The PERT approach is stated in some books and papers,but there is no deep investigation on the application in the schedule risk assessment.This paper investigates the PERT work process and takes a valuable try on the construction schedule risk assessment by using case studies.The utilization in the estimate the construction liquidated damage with the uncertainties is performed,which also can be used in the insurance company to calculate the insurance premium.  相似文献   
3.
随着全球经济的快速发展和陆地自然资源的日趋紧缺,海洋开发利用已成为许多国家重要的经济战略。我国是海洋大国,丰富的岛屿资源是我国海洋开发的重要依托。开发海岛资源,主要从发展海洋渔业入手,但不同的发展模式显示出不同的发展前景。在对山东省长岛县和辽宁省长海县的经济发展模式做简要对比分析后,探寻海岛经济可持续发展规律,并对相关问题进行思考。  相似文献   
4.
This study presents how Hydro-Quebec manages its short-term financial risks. The quantitative hedging model is articulated over forward and volatility premia and constrained by a yearly risk limit provided by the firm's Finance Committee. The hedging solutions provide the optimal linear hedging parameters and option strike levels. The second part of the paper is devoted to a theoretical analysis of the sensitivity of the optimal solutions to changes in the premia, by means of the general implicit function theorem.  相似文献   
5.
    
We examine the impact of COVID-19 pandemic crisis on the pricing efficiency and asymmetric multifractality of major asset classes (S&P500, US Treasury bond, US dollar index, Bitcoin, Brent oil, and gold) within a dynamic framework. Applying permutation entropy on intraday data that covers between April 30, 2019 and May 13, 2020, we show that efficiency of all sample asset classes is deteriorated with the outbreak, and in most cases this deterioration is significant. Results are found to be robust under different analysis schemes. Brent oil is the highest efficient market before and during crisis. The degree of efficiency is heterogeneous among all markets. The analysis by an asymmetric multifractal detrended fluctuation analysis (A-MF-DFA) approach shows evidence of asymmetric multifractality in all markets which rise with the scales. The inefficiency is higher during downward trends before the pandemic crisis as well as during COVID-19 except for gold and Bitcoin. Moreover, the pandemic intensifies the inefficiency of all markets except Bitcoin. Findings reveal increased opportunities for price predictions and abnormal returns gains during the COVID-19 outbreak.  相似文献   
6.
Abstract

Background:

Tiotropium has been shown to reduce exacerbations and improve quality of life for patients with chronic obstructive pulmonary disease (COPD), a lung disease characterized by a persistent and progressive airflow limitation.

Objectives:

To present a systematic literature review of the cost effectiveness of treatment with tiotropium compared with other currently used treatments for COPD.

Methods:

A systematic search was performed via PubMed, the Cochrane database, and EMBASE from 2002 to 2009. Methods and results by study design and by country were compared.

Results:

Seventeen studies were included in the review. Study designs were characterized as follows: modeling based on clinical trial data, and empirical analysis based on either clinical trial or observational data. Comparing monotherapy regimens (12 studies), all study designs found that treatment with tiotropium was associated with lower costs for hospitalisation and other non-drug services. Total costs, including the costs of maintenance drugs, were lower with tiotropium in some, but not all, of the studies. Tiotropium was shown to be cost effective based on commonly accepted benchmark values. Limitations of the review included the wide variety of outcome measures used in different studies, the limited number of observational database studies for monotherapy, and limited data for combination therapy regimens.

Conclusions:

The main conclusions of the economic evaluations derived from clinical trial data at the time of product approval and from later observational data reflecting clinical use are similar: use of tiotropium monotherapy is associated with lower hospital and other non-drug costs and better health outcomes and is either cost saving or cost effective compared with other maintenance monotherapies.  相似文献   
7.
Indicative bidding is a practice commonly used in sales of complex and very expensive assets. Theoretical analysis shows that efficient entry is not guaranteed under indicative bidding, since there is no equilibrium in which more qualified bidders are more likely to be selected for the final sale. Furthermore, there exist alternative bid procedures that, in theory at least, guarantee 100% efficiency and higher revenue for the seller. We employ experiments to compare actual performance between indicative bidding and one of these alternative procedures. The data shows that indicative bidding performs as well as the alternative procedure in terms of entry efficiency, while having other characteristics that favor it over the alternative procedure. Our results provide an explanation for the widespread use of indicative bidding despite the potential problem identified in the equilibrium analysis.  相似文献   
8.
    
This paper investigates market efficiency of the Jamaica Stock Exchange (JSE). Together, weak and semi-strong form efficiency claim that historical and newly released public information do not predict future stock price movement. We test both forms of market efficiency by analyzing stock price behavior during times of abnormal trading volume and around the release dates of earnings information. Abnormal trading volume may be driven by liquidity demand or reflect new or private information flow to the market. Using JSE data over the period 2000 to 2021, we find price dynamics consistent with price pressure as firms experience negative abnormal returns on the day of abnormal trading activity but offsetting positive abnormal stock returns on the following day. Further findings show post earnings announcement drift on the JSE. Taken as a whole, the evidence suggests violations of market efficiency and has implications for capital allocation in this emerging market.  相似文献   
9.
Objective:

The objective for the research was to evaluate the direct healthcare costs for Crohn’s disease (CD) patients categorized by adherence status.

Methods:

Adult patients with ≥1 claim for infliximab and ≥2 claims for CD who were continuously insured for 12 months before and after their first infliximab infusion (index date) were identified in a 2006–2009 US managed care database. Patients were excluded if they had rheumatoid arthritis claims, received infliximab billed as a pharmacy benefit, or received another biologic drug. Patients were categorized as being either adherent or intermittently adherent to infliximab using a pre-defined algorithm. Total and component direct costs, CD-related costs, rates of surgery, and days of hospitalization were estimated for the 360-day post-index period. Propensity weighted generalized linear models were used to adjust the cost estimates for potential confounding variables.

Results:

The total propensity weighted cost for infliximab adherent patients was $40,425 (95% CI?=?[$38,686, $42,242]), compared to $41,082 (95% CI?=?[$38,163, $44,223]) for the intermittently adherent (p?=?0.71). However, adherent patients had lower total direct medical costs, exclusive of infliximab, that were $13,097 (95% CI?=?[$12,141, $14,127]) compared with $20,068 (95% CI?=?[$17,676, $22,784]) for intermittently adherent patients as a result of substantially lower hospital and outpatient costs (p?Conclusions:

Greater drug-related costs for infliximab adherent patients were offset by lower costs from hospitalization and outpatient visits. These findings indicate that adherent patients have improved clinical outcomes, at a similar aggregate cost, than patients who are only intermittently adherent to therapy.  相似文献   
10.
同生辉 《当代经济科学》2012,1(1):66-74,126
本文考察了当兼并交易具有哪些特征时,收购方公司更可能会在兼并交易中雇用投资银行作为其兼并交易的财务顾问。研究结果表明,在下列情况下,收购方公司更有可能雇用投资银行作为其兼并交易的财务顾问:兼并交易较复杂,收购方公司的兼并交易经验不足,收购方公司仅收购目标公司部分资产或股权,兼并交易价格较高,兼并交易为敌意收购,收购方公司在金融行业运营,目标公司在很多行业经营。  相似文献   
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