Search results

The purpose of this study was to create an air movement operations planning model to rapidly generate air mission request (AMR) assignment and routing courses of action (COA) in order to minimize unsupported AMRs, aircraft utilization and routing cost.

In this paper, the US Army Aviation air movement operations planning problem is modeled as a mixed integer linear program (MILP) as an extension of the dial-a-ride problem (DARP). The paper also introduces a heuristic as an extension of a single-vehicle DARP demand insertion algorithm to generate feasible solutions in a tactically useful time period.

The MILP model generates optimal solutions for small problems (low numbers of AMRs and small helicopter fleets). The heuristic generates near-optimal feasible solutions for problems of various sizes (up to 100 AMRs and 10 helicopter team fleet size) in near real time.

Due to the inability of the MILP to produce optimal solutions for mid- and large-sized problems, this research is limited in commenting on the heuristic solution quality beyond the numerical experimentation. Additionally, the authors make several simplifying assumptions to generalize the average performance and capabilities of aircraft throughout a flight.

This research is the first to solve the US Army Aviation air movement operations planning problem via a single formulation that incorporates multiple refuel nodes, minimization of unsupported demand by priority level, demand time windows, aircraft team utilization penalties, aircraft team time windows and maximum duration and passenger ride time limits.

Demonstrate proof-of-concept for conducting NFL Draft trades on a blockchain network using smart contracts.

Using Ethereum smart contracts, the authors model several types of draft trades between teams. An example scenario is used to demonstrate contract interaction and draft results.

The authors show the feasibility of conducting draft-day trades using smart contracts. The entire negotiation process, including side deals, can be conducted digitally.

Further work is required to incorporate the full-scale depth required to integrate the draft trading process into a decentralized user platform and experience.

Cutting time for the trade negotiation process buys decision time for team decision-makers. Gains are also made with accuracy and cost.

Full-scale adoption may find resistance due to the level of fan involvement; the draft has evolved into an interactive experience for both fans and teams.

This research demonstrates the new application of smart contracts in the inter-section of sports management and blockchain technology.

The study aims to investigate the impact of additive manufacturing (AM) on the performance of a spare parts supply chain with a particular focus on underlying spare part demand patterns.

This work evaluates various AM-enabled supply chain configurations through Monte Carlo simulation. Historical demand simulation and intermittent demand forecasting are used in conjunction with a mixed integer linear program to determine optimal network nodal inventory policies. By varying demand characteristics and AM capacity this work assesses how to best employ AM capability within the network.

This research assesses the preferred AM-enabled supply chain configuration for varying levels of intermittent demand patterns and AM production capacity. The research shows that variation in demand patterns alone directly affects the preferred network configuration. The relationship between the demand volume and relative AM production capacity affects the regions of superior network configuration performance.

This research makes several simplifying assumptions regarding AM technical capabilities. AM production time is assumed to be deterministic and does not consider build failure probability, build chamber capacity, part size, part complexity and post-processing requirements.

This research is the first study to link realistic spare part demand characterization to AM supply chain design using quantitative modeling.

The purpose of this paper is to investigate US noncombatant evacuation operations (NEO) in South Korea and devise planning and management procedures that improve the efficiency of those missions.

It formulates a time-staged network model of the South Korean noncombatant evacuation system as a mixed integer linear program to determine an optimal flow configuration that minimizes the time required to complete an evacuation. This solution considers the capacity and resource constraints of multiple transportation modes and effectively allocates the limited assets across a time-staged network to create a feasible evacuation plan. That solution is post-processed and a vehicle routing procedure then produces a high resolution schedule for each individual asset throughout the entire duration of the NEO.

This work makes a clear improvement in the decision-making and resource allocation methodology currently used in a NEO on the Korea peninsula. It immediately provides previously unidentifiable information regarding the scope and requirements of a particular evacuation scenario and then produces an executable schedule for assets to facilitate mission accomplishment.

The significance of this work is not relegated only to evacuation operations on the Korean peninsula; there are numerous other NEO and natural disaster related scenarios that can benefit from this approach.

This paper aims to clarify the relationship between corporate capital investments and business cycles. Specifically, a major purpose of this paper is to investigate whether there are inherent differences in corporate investment patterns and whether the stock market exhibits different reactions to the value relevance of capital expenditures across different business conditions.

The authors use pooled ordinary least square regressions with archival stock price data and financial data from CRSP and Compustat. The authors regress buy and hold returns on the main test variables and control variables that are identified to be related to the investment literature.

This paper provides empirical evidence that US firms’ capital expenditures are more value relevant to capital market participants during expansionary business cycles and, conversely, less value relevant during contractionary business cycles. This evidence validates previous literature that has found the information content of capital expenditures to be uncertain and cyclical in nature.

The main limitation of this paper, as with other work dealing with stock returns and archived financial data, is that the authors try to match stock returns with contemporaneous financial data in an association study context. The precise mapping in this methodology is always challenging and has been questioned in the literature.

This paper has various implications for capital market participants. Capital expenditures are good news for investors, but they will make a better investment when firms make capital investments during an expansionary period. Creditors deciding whether to extend credit to firms would benefit from more accurate information on the viability of long-term investment. The results also suggest to creditors that an excessive number of loans during the contractionary period may be suboptimal because firms’ returns on capital investment are smaller in that period than in the expansionary period.

Given the valuation of implications of long-term capital investments across different business conditions, this paper sheds light on asset allocations for mutual funds, institutional investors who are entrusted with investors’ investments including retirement funds.

This paper fulfils an identified need to study how capital investments are valued differently across different business conditions.

The purpose of this paper is to develop a consolidated framework for government e-procurement (e-GP) performance measurement based on the importance internal stakeholders attach to performance measures and metrics, providing in-depth understanding of their interest in e-GP performance.

This study is divided into two main phases: internal stakeholder identification and consolidation of performance measures and metrics. The mixed-methods approach follows semi-structured expert interviews with questionnaires collected from 413 internal stakeholders.

Five internal stakeholder groups were identified: management, auditors, financial officers, service users, and service support staff. Eight measures and 44 corresponding metrics were consolidated, and 21 significantly distinct performance metrics were identified from stakeholders’ perceptions. As expected, financial measures were most important to financial officers, while contract management was most important to service support staff.

Although e-GP processes can vary by country, this study’s approach to developing an e-GP performance measurement framework is adaptable, offering beneficial guidelines for designing e-GP performance measurement systems.

This paper goes beyond the existing literature by magnifying the internal stakeholder roles and perceptions of importance, as reflected in the consolidated e-GP performance measurement framework. The consolidation approach with theoretical references (new public management, transaction cost economics, and institutional theory) yielded comprehensive e-GP-specific performance measures and metrics, providing a rigorous approach to measuring e-GP performance.

The primary aim of the research presented in this paper is to address the gap in the literature with regard to the factors that affect the uptake and application of e‐procurement within the public sector.

This analysis was achieved through five in‐depth case studies – based upon extensive interviews, observation and documentation reviews ‐ conducted within central and local government organisations.

The study shows that despite being very different in terms of their form and function, each of the five case study organisations had achieved similar levels of progress in terms of their adoption of e‐procurement technologies. In short every organisation had already adopted BACS, all five were also actively planning to implement: e‐tendering; e‐award; e‐contract and e‐catalogue systems, but none had any intention of adopting e‐marketplaces or e‐auctions.

The results of this study will help individual organisations to better understand their current situations and the barriers that will need to be overcome before they can significantly expand their adoption of e‐procurement technologies.

In addition to presenting one of the first detailed studies of the adoption of e‐procurement technologies, this study also breaks new ground through its use of the lens of “Institutional theory” to help interpret the findings.

This chapter explores queer theory as a “thought of a method” in educational ethnography by sharing stories of two third grade boys and situating them in a discussion of Britzman’s ideas about reading and Butler’s notion of fantasy. The stories are presented as a possible queer educational ethnography, in which the ethnographer writes the fantastic narrative of the boys as they read creatively to reveal and unsettle gender and reading as sites of constraint to which other constraints adhere. The boys’ reading itself is a queer reading of these constraints and as such makes alterity visible and possible. The study and the methodological framework suggest that educational ethnographers and other adults who work in schools should become attuned to the markers of constraint and alterity, so as to recognize, shelter, and maintain the alterity that children make possible. The chapter asserts children must be allowed to read for alterity, and shows how fantastic narratives that emerge from such readings are limited by the hushing of individuals who disallow alterity in classrooms. Ultimately, this chapter is relevant to ethnographers of education in that it suggests that queer theory not only is necessary to narrate and thus shelter the ways that gender can and should be unsettled in classrooms, but also allows us to narrate and shelter other queer urgencies related to fear, violence, and vulnerability that children experience or share in classrooms. Implications for the current climate of school reform based on standardization of curriculum are also discussed.

As a consequence of the global financial and economic crisis, the European Commission recently reformed the audit market. One objective was to restore public trust in the auditing profession and thus to enhance the audit function. This study investigates whether perceptions of auditor independence and audit quality are influenced by audit firm rotation, auditor retention and joint audits, because regulators argue that these instruments can improve auditor independence and audit quality. Therefore, we conduct an experiment with bank directors and institutional investors in Germany. The results indicate a negative main effect for joint audits on perceived auditor independence, and that a rotation cycle of 24 years marginally significantly impairs participant perceptions of audit quality, compared to a rotation cycle of only ten years. Besides the main effects, planned contrast tests suggest a negative interaction between rotation and joint audit on participant perceptions of auditor independence. Moreover, a negative interaction effect is revealed between rotation after 24 years and retention on perceptions of audit quality. It is particularly noteworthy that we failed to identify a positive impact of the regulatory measures taken or supported by the European Commission on perceptions of auditor independence and audit quality.

The prevalence, correlates (child behaviour problems and negative parenting) and determinants (risk and protective factors) of parental need for support were examined in a community sample of 177 mothers with a child aged 1.5‐3.5 years, in order to draw a profile of families that need parenting support. A substantial number of the mothers reported needing support (40% reported need for information, 10% reported family and social support needs). This need was related to child behaviour problems and to negative parenting. Maternal depression, difficult temperament of the child and negative life events, as well as total number of risk factors, significantly predicted the need for support. Satisfaction with support (but not number of support sources) acted as a protective factor.