Alenka Baggia

Data Envelopment Analysis - Basic Models and their Utilization

Data Envelopment Analysis - Basic Models and their Utilization Data Envelopment Analysis (DEA) is a decision making tool based on linear programming for measuring the relative efficiency of a set of comparable units. Besides the identification of relatively efficient and inefficient units, DEA identifies the sources and level of inefficiency for each of the inputs and outputs. This paper is a survey of the basic DEA models. A comparison of DEA models is given. The effect of model orientation (input or output) on the efficiency frontier and the effect of the convexity requirements on returns to scale are examined. The paper also explains how DEA models can be used to assess efficiency.

Optimization of a Call Centre Performance Using the Stochastic Queueing Models

Abstract Background A call centre usually represents the first contact of a customer with a given company. Therefore, the quality of its service is of key importance. An essential factor of the call centre optimization is the determination of the proper number of operators considering the selected performance measure. Results of previous research show that this can be done using the queueing theory approach. Objectives: The paper presents the practical application of the stochastic queueing models aimed at optimizing a Slovenian telecommunication provider’s call centre. Methods/Approach: The arrival and the service patterns were analysed, and it was concluded that the call centre under consideration can be described using the M/M/r {infinity/infinity/FIFO} queueing model. Results: An appropriate number of operators were determined for different peak periods of the working day, taking into consideration the following four performance measures: the expected waiting time, the expected number of waiting customers, the probability that a calling customer will have to wait, and the call centre service level. Conclusions: The obtained results prove the usefulness and applicability of the queueing models as a tool for a call centre performance optimization. In practice, all the data needed for such a mathematical analysis are usually provided. This paper is aimed at illustrating how such data can be efficiently exploited.

Awareness and attitude towards Green IS in Slovenian enterprises

Abstract Background: This study draws upon the use of Information Systems in support of achieving sustainability, known as Green IS. Furthermore, this study builds on the premise that Green IS offers the opportunity for organizations to act proactively in terms of environmental preservation as well as to mitigate the effects of global climate change and other environmental problems. Aim: In particular, this study aims to assess the extent of awareness among managers regarding the use and the acceptance of Green IS in Slovenian enterprises. Method: Using empirical data based on a large-scale survey among senior managers within Slovenian enterprises this study utilized several statistical methods (such as t-test, analysis of variance and multiple linear regression) to analyse the research questions. Results: In general, findings seem to suggest that institutional mechanisms might be a plausible explanation for differences regarding the attitude towards Green IS adoption. For instance, enterprises with at least one implemented sustainability related certificate expressed higher levels of willingness to use Green IS in order to facilitate the achievement of sustainable development. Moreover, the results of the regression analysis revealed that both Institutional Mimetic pressure and Internal Environment Impact has positive impact on Green IS adoption. Conclusion: The main conclusion is that the internal environmental impact is considered the most influential factor of the attitude towards Green IS adoption. The culture or individual perception of managers and employees play an important role in the Green IS adoption. Indeed, enterprises that have no intention of improving their environmental performance, but adopt Green IS by the means of seeking legitimacy among external stakeholders, cannot provide a sustainable improvement in environmental management.

Discrete event simulation of administrative and medical processes.

Background: Medical processes are often obstructed by administrative ones. The main issue in administrative processes is uneven workload resulting in an increased possibility of human errors. The system approach assures that medical and administrative processes are integrated. According to research reports and best practices, discrete event simulation is a proper method to implement the system approach. Methods: A detailed analysis of the administrative processes was performed using interviews, UML diagrams and flowcharts. Based on the data gathered from the information system and measurements on the site, the distribution of patient arrivals and service times were modelled. The aim of discrete event simulation models was to replicate the behaviour of the existing system (separate administration) and to simulate the changes proposed (joint administration). Results: Average utilizations of administrative personnel in 100 simulation runs for specific clinical departments are: 83.8 % at the Department of Rheumatology, 61.9 % at the Department of Hypertension, and 47.2 % at the Veteran’s Medical Unit. Should joint administration be applied, the average utilization of administrative personnel would be 74.3 %. Conclusions: Discrete event simulation provedthat joint administration would contribute to a more even workload distribution among administrative personnel, higher quality of service and easier human resource management. The presented approach can be efficiently applied to large-scale systems e.g. organizational changes of processes in Specialist Outpatient Clinics.

Implementation of the Scheduling Domain Description Model

Implementation of the Scheduling Domain Description Model This paper presents the problem of auniform scheduling domain description. It was established that the algorithm used for scheduling is general, disregarding the type of scheduling domain. On the basis of five different scheduling domains, a general description model was developed. The research is focused on the programming application of the resource scheduling model, presented as a UML class diagram. Diverse meta-languages for the model description were considered. Of these XML, an EAV model and object oriented languages have shown to be the most effective. Even though Java is not widely used as a description language, it has proved effective as a meta-language for the description of the extensible scheduling model. Implementacija modela za opis domene razporejanja V članku je predstavljen problem splošnega opisa domene razporejanja. Ugotovljeno je bilo, da je algoritem razporejanja splošen ne glede na tip problema razporejanja. Na osnovi petih različnih domen razporejanja je bil razvit splošni model opisa. Raziskava se osredotoča na programsko aplikacijo modela razporejanja virov, ki je predstavljen kot UML diagram razreda. Za opis modela so bili preučeni različni meta jeziki. Med njimi so se XML, EAV model in objektno orientirani jeziki pokazali kot najbolj uporabni. Čeprav se Java ne uporablja pogosto kot opisni jezik, se je izkazala kot najbolj učinkovit meta jezik za opis razširljivega modela razporejanja.

Factors Affecting the Intentions to Use RFID Subcutaneous Microchip Implants for Healthcare Purposes

Abstract Background and Purpose: While there are many studies regarding the adoption of Radio Frequency Identification Devices (RFID), only a few of them deal with RFID subcutaneous microchip (RFID-SM) usage by individuals. After the first in vivo tests conducted on volunteers from 1998 to 2000, the use of RFID-SM in healthcare remains limited. This study examines the likelihood of adopting RFID-SM in healthcare from the end user’s point of view. Design/Methodology/Approach: The aim of this paper is to develop and evaluate the model for analysing the acceptance of RFID-SM adoption. An extended Technology Acceptance Model (TAM) for RFID-SM adoption is proposed and empirically tested in a cross-sectional study. Online survey was conducted using a convenience sample of 531 respondents. In addition to the three original components of TAM (Perceived Usefulness, Perceived Ease of Use, and Behavioural Intentions to Use), three external variables (Health Concerns, Perceived Trust, and Age) were also included in the model. The model was validated with confirmatory factor analysis and structural equation modeling techniques. Results: Perceived Usefulness has a significant impact on behavioural intentions to adopt RFID-SM in the future, while the influence of Perceived Ease of Use is not significant. The most influential external variable is Perceived Trust, indicating the lack of confidence in personal data security ensured by the state and other institutions. As expected, Health Concerns factor has a negative effect on the Perceived Trust and Perceived Usefulness of RFID-SM. Conclusion: The results of the empirical study prove that all external variables considered in the model significantly influence the RFID-SM adoption. The Perceived Ease of Use is irrelevant to the attitude towards the RFID-SM adoption. In addition to the proposed model, the analysis of gathered data shows that the positive attitude toward the use of RFID-SM in healthcare is rising.

Behaviour Intentions to Use RFID Subcutaneous Microchips: A Cross-sectional Slovenian Perspective

This paper presents the second iteration results of a study investigating the possibility of radio frequency identification device subcutaneous microchip (RFID-SM) usage as a substitute for personal identification, healthcare issues, shopping or payments, and home usage. Our aim was to investigate the readiness to use SM-RFID in everyday life. In the study, we used an extended Technology Acceptance Model (TAM) to verify the main concerns regarding the use of RFID-SM among Slovenian people. The survey responses were gathered from October until December 2016. After evaluating the model, it can be concluded that the fit of the model is good and the significant path of dependence are similar as in the first study from 2014. Similar to previous results, the Health Concerns have a negative effect on the Perceived Trust and Perceived Usefulness of SM-RFID adoption. On the other hand, the Perceived Trust and Perceived Usefulness have a positive effect on the Behaviour Intention to use SM-RFID.

Airport Operations Modelling: Agent Based Modelling of Ground Crews

Contribution presents the results of design research project aimed at the development of a simulation model for regional airports ground crew operations using a novel hybrid DES-ABM approach. We have used DES methodology to model the aspects of airport operations that are static or outside the main scope of our model, e.g. flight traffic, and ABM methodology to model the operation of ground crews, where the scheduling and work processes are variable. Use of ABM allows us to model the dynamic aspects of ground crew operations, such as dynamic scheduling and assignment of crews to flights, making the model more realistic and more flexible than when using DES alone. The hybrid DES-ABM simulation model is to be used in a ground crew scheduling system development for validation and optimization of heuristic scheduling algorithms. The resulting model contributes to the knowledge of domain experts with measurable improvements of ground crew scheduling solutions.

Markov Analysis of Students’ Performance and Academic Progress in Higher Education

Abstract Background: The students’ progression towards completing their higher education degrees possesses stochastic characteristics, and can therefore be modelled as an absorbing Markov chain. Such application would have a high practical value and offer great opportunities for implementation in practice. Objectives: The aim of the paper is to develop a stochastic model for estimation and continuous monitoring of various quality and effectiveness indicators of a given higher education study programme. Method: The study programme is modelled by a finite Markov chain with five transient and two absorbing states. The probability transition matrix is constructed. The quantitative characteristics of the absorbing Markov chain, like the expected time until absorption and the probabilities of absorption, are used to determine chosen indicators of the programme. Results: The model is applied to investigate the pattern of students’ enrolment and their academic performance in a Slovenian higher education institution. Based on the students’ intake records, the transition matrix was developed considering eight consecutive academic seasons from 2008/09 until 2016/17. The students’ progression towards the next stage of the study programme was estimated. The expected time that a student spends at a particular stage as well as the expected duration of the study is determined. The graduation and withdrawal probabilities were obtained. Besides, a prediction on the students’ enrolment for the next three academic years was made. The results were interpreted and discussed. Conclusion: The analysis presented is applicable for all higher education stakeholders. It is especially useful for a higher education institution’s managers seeing that it provides useful information to plan improvements regarding the quality and effectiveness of their study programmes to achieve better position in the educational market.

Airport Ground Crew Scheduling Using Heuristics and Simulation

International airports are complex systems that require efficient operation and coordination of all their departments. Therefore, suitable personnel and equipment scheduling solutions are vital for efficient operation of an airport as a system. Many general solutions for fleet scheduling are available; however, there is a lack of scheduling solutions for airport ground crews, especially for work groups with overlapping skills. In the presented case, a scheduling solution for airport ground crew and equipment in a small international airport is described. As analytical methods are unsuitable for the system in question, the proposed scheduling solution is based on heuristics. A combined agent based and discrete event simulation model was developed to validate and improve the heuristic algorithms until they produced acceptable schedules and shifts. The algorithms first compute the requirements for workforce and equipment based on flight schedules and stored heuristic criteria. Workforce requirements are then optimized using time shifting of tasks and task reassignments, which smooth the peaks in workforce requirements, and finally the simulation model is used to verify the generated schedule. The scheduling procedure is considerably faster than manual scheduling and allows dynamic rescheduling in case of disruptions. The presented schedule generation and optimization solution is flexible and adaptable to other similar sized airports.