• International conference on construction engineering and project management
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• 2022.06a
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• pp.196-203
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• 2022

The resource constrained scheduling problem (RCSP) constitutes one of the most challenging problems in Project Management, as it combines multiple parameters, contradicting objectives (project completion within certain deadlines, resource allocation within resource availability margins and with reduced fluctuations), strict constraints (precedence constraints between activities), while its complexity grows with the increase in the number of activities being executed. Due to the large solution space size, this work investigates the application of Genetic Algorithms to approximate the optimal resource alolocation and obtain optimal trade-offs between different project goals. This analysis uses the cost of exceeding the daily resource availability, the cost from the day-by-day resource movement in and out of the site and the cost for using resources day-by-day, to form the objective cost function. The model is applied in different case studies: 1 project consisting of 10 activities, 4 repetitive projects consisting of 40 activities in total and 16 repetitive projects consisting of 160 activities in total, in order to evaluate the effectiveness of the algorithm in different-size solution spaces and under alternative optimization criteria by examining the quality of the solution and the required computational time. The case studies 2 & 3 have been developed by building upon the recurrence of the unit/sub-project (10 activities), meaning that the initial problem is multiplied four and sixteen times respectively. The evaluation results indicate that the proposed model can efficiently provide reliable solutions with respect to the individual goals assigned in every case study regardless of the project scale.

• Journal of Communications and Networks
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• v.8 no.4
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• pp.401-409
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• 2006

Orthogonal frequency division multiplexing (OFDM) and multiple input multiple output (MIMO) technologies provide additional dimensions of freedom with spectral and spatial resources for radio resource management. Multi-dimensional radio resource management has recently been identified to exploit the full dimensions of freedom for more flexible and efficient utilization of scarce radio spectrum while provide diverse quality of service (QoS) guarantees. In this work, a multi-dimensional radio resource scheduling scheme is proposed to achieve above goals in hybrid orthogonal frequency division multiple access (OFDMA) and space division multiple access (SDMA) systems. Cochannel interference (CCI) introduced by frequency reuse under SDMA is eliminated by frequency division and time division between highly interfered users. This scheme maximizes system throughput subjected to the minimum data rate guarantee. for heterogeneous users and transmit power constraint. By numerical examples, system throughput and fairness superiority of the our scheduling scheme are verified.

• Journal of Family Resource Management and Policy Review
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• v.22 no.3
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• pp.1-19
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• 2018

This study was aimed at exploring gender differences in time use and time famine between single-parent families. Data were obtained from the time use surveys, that were conducted by the Korea National Statistical Office in 2014. A total of 500 time diaries (168 from fathers, 332 from mothers) from single-parents aged between 20 and 59 were analyzed. Descriptive statistics, chi-square test, and t-test were used for the statistical analyses. Results indicated that the single-parent families exhibit gender differences in time use and subjective time famine. The single-mothers spend a significantly longer amount of time on housework and less time on leisure than do the single-fathers. The single fathers and mothers also differ in time use and time famine according to employment status and working days on/off.

• Journal of Information Processing Systems
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• v.19 no.4
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• pp.450-464
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• 2023

To address the problems of large system overhead and low timeliness when dealing with task scheduling in mobile edge cloud computing, a task scheduling and resource management strategy for edge cloud computing based on an improved genetic algorithm was proposed. First, a user task scheduling system model based on edge cloud computing was constructed using the Shannon theorem, including calculation, communication, and network models. In addition, a multi-objective optimization model, including delay and energy consumption, was constructed to minimize the sum of two weights. Finally, the selection, crossover, and mutation operations of the genetic algorithm were improved using the best reservation selection algorithm and normal distribution crossover operator. Furthermore, an improved legacy algorithm was selected to deal with the multi-objective problem and acquire the optimal solution, that is, the best computing task scheduling scheme. The experimental analysis of the proposed strategy based on the MATLAB simulation platform shows that its energy loss does not exceed 50 J, and the time delay is 23.2 ms, which are better than those of other comparison strategies.

• Journal of Family Resource Management and Policy Review
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• v.15 no.2
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• pp.63-84
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• 2011

This qualitative case study focused on the workers' flexibility needs. We selected eight full-time workers from one 2009 family friendly certified firm for observation and in-depth interview. The workers are categorized into three groups; male employees with housewives, double income family workers depending on extended family, and double income family workers depending on paid babysitter. The spouse's work status and informal extended familial support to child care were crucial factors to influence their work family life styles and flexibility needs. The flex time is the most desirable everyday needs for the dual working child caring parents depending on the paid help. And the female workers' concerned about the stigma effect of the institutionalized flexibility use of the inferior labors.

• Journal of Family Resource Management and Policy Review
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• v.19 no.1
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• pp.163-180
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• 2015

The purpose of this study was to explore a typology of time allocation, investigate determinants of time allocation types, and analyze differences in time use satisfaction by the types of time use of the elderly. The data source for this research was the 2009 Time Use Survey conducted by the Korea National Statistical office (KNSO). The 4,699 time diaries (3,552 for weekday, 1,147 for Sunday) completed by the elderly over the age of 60 were analyzed using mean, standard deviation, chi-square, cluster analysis, ANOVA analysis, Duncan test, and multinomial logistic regression analysis. Time allocation of the elderly was classified into four types: personal care oriented, work oriented, leisure oriented, and balanced type. Gender, age, education, employment status, income, and the presence of spouse were identified as determinants for each type. According to the types of time allocation, time use satisfaction was different on week days.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.12
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• pp.204-209
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• 2014

This paper has described a QoS mechanism and management for multimedia object transport protocol. Resource manager reports the system resource information to the QoS manager. Based on the combination of two informations, the more effective QoS management can be achieved by organic combination between them on the protocol time domain. Therefore, it is possible for QoS manager to decide call admission control quickly and detect and react the performance fluctuations in protocol time domain.

• Journal of Communications and Networks
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• v.15 no.5
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• pp.469-475
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• 2013

In this paper, we propose an efficient interference management technique which controls the number of resource blocks (or subcarriers) shared with other cells based on statistical interference levels among cells. The proposed technique tries to maximize average throughput of a femto cell user under a constraint on non-real time control of a femto cell network while guaranteeing a target throughput value of a macro cell user. In our proposed scheme, femto cells opportunistically use resource blocks allocated to other cells if the required average user throughput is not attained with the primarily allocated resource blocks. The proposed method is similar to the underlay approach in cognitive radio systems, but resource block sharing among cells is statistically controlled. For the statistical control, a femto cell sever constructs a table storing average mutual interference among cells and periodically updates the table. This statistical approach fully satisfies the constraint of non-real time control for femto cell networks. Our simulation results show that the proposed scheme achieves higher average femto user throughput than conventional frequency reuse schemes for time varying number of users.

• International conference on construction engineering and project management
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• 2015.10a
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• pp.158-160
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• 2015

Efficient scheduling and resource management are the key factor to reduce construction project budget (e.g., labor cost, equipment cost, material cost, etc.). Resource-based line of balance (LOB) technique has been used to complement the limitations of existing time-driven scheduling techniques (e.g., critical-path method). Optimizing construction alternatives contributes to cost savings while honoring the project deadline. However, existing LOB scheduling is lack of identifying optimal resource combination. This study presents a method which identifies the optimal construction alternatives, hence achieving resource minimization in a repetitive construction by using genetic algorithm (GA). The method provides efficient planning tool that enhances the usability of the system.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.13 no.9
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• pp.4349-4371
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• 2019

Moldable parallel tasks are widely used in different areas, such as weather forecast, biocomputing, mechanical calculation, and so on. Considering the deadline and the speedup, scheduling moldable parallel tasks becomes a difficulty. Past work majorly focuses on the LA (List Algorithms) or OMA (Optimizing the Middle Algorithms). Different from prior work, our work normalizes execution time and makes all tasks have the same scope in normalized execution time: [0,1], and then according to the normalized execution time, a method is used to search for the reference execution time without considering the deadline of tasks. According to the reference execution time, we get an initial scheduling result based on AFCFS (Adaptive First Comes First Served) policy. Finally, a heuristic approach is used to improve the performance of the initial scheduling result. We call our method HSRET (a Heuristic Scheduling method based on Reference Execution Time). Comparisons to other methods show that HSRET has good performance in AWT (Average Waiting Time), AET (Average Execution Time), and PUT (Percentages of Unfinished Tasks).