• International Journal of Computer Science & Network Security
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• v.23 no.4
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• pp.156-165
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• 2023

IEEE 802.15.4e-TSCH is recognized as a wireless industrial sensor network standard used in IoT systems. To ensure both power savings and reliable communications, the TSCH standard uses techniques including channel hopping and bandwidth reserve. In TSCH mode, scheduling is crucial because it allows sensor nodes to select when data should be delivered or received. Because a wide range of applications may necessitate energy economy and transmission dependability, we present a distributed approach that uses a cluster tree topology to forecast scheduling requirements for the following slotframe, concentrating on the Poisson model. The proposed Optimized Minimal Scheduling Function (OMSF) is interested in the details of the scheduling time intervals, something that was not supported by the Minimal Scheduling Function (MSF) proposed by the 6TSCH group. Our contribution helps to deduce the number of cells needed in the following slotframe by reducing the number of negotiation operations between the pairs of nodes in each cluster to settle on a schedule. As a result, the cluster tree network's error rate, traffic load, latency, and queue size have all decreased.

• Journal of the Korea Institute of Building Construction
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• v.14 no.5
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• pp.467-476
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• 2014

According to the expanding of construction machinery works, the number of civil complaints demanding compensations are increasing continuously from surrounding residents due to the noise from construction fields. However, the noise is usually managed restrictedly during the construction phase rather than prevented in advance. So, the efforts to solve the noise problem are occurring only after complaints have been made. Also, excessive cost and time consuming in order to solve the complaints negatively affects to construction companies. Therefore, the purpose of this study is to develop an optimized scheduling process model for controlling the noise in construction field by considering the planned time, cost, and the number of equipment before construction. In addition, this process model is expected to provide a useful information about the cost comparison between the original planned cost plus compensation and the optimized cost considering noise limitation so that the site managers can manage their projects effectively.

• Korean Journal of Construction Engineering and Management
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• v.16 no.5
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• pp.54-64
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• 2015

The modular construction has several advantages such as high quality of product, safe work condition and short construction duration. The manufacturing planning of modular construction should consider time frame of manufacturing, transport and erection process with limited resources (e.g., modular units, transporter and workers). The manufacturing planning of multi modular construction project manages the modular construction's characteristics and diversity of projects, as a type of modular unit, modular unit quantities, and date for delivery. However, current modular manufacturing planning techniques are weak in dealing with resource interactions and each project requirement in multi modular construction project environments. Inefficient allocation of resources during multi modular construction project may cause delays and cost overruns to construction operation. In this circumstance, this research suggest a manufacturing planning model for schedule optimization of multi project of modular construction, using genetic algorithm as one of the powerful method for schedule optimization with multiple constrained resources. Comparing to the result of the existed schedule of case study, setting optimized scheduling for multi project decrease the total factory producing schedule. By using proposed optimization tool, efficient allocation of resource and saving project time is expected.

• Proceedings of the KSME Conference
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• 2004.11a
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• pp.522-527
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• 2004

Resealed Simulated Annealing (RSA) has been devised for improving the disadvantage of Simulated Annealing (SA) which require tremendous amount of computation time. RSA and SA have been for optimization of satellite structures and for comparison of results from two algorithms. As a practical application, a satellite structure is optimized by the two algorithms. Weights of satellite upper platform and propulsion module are minimized. MSC/NASTRAN is used for the static and dynamic analysis. The optimization results of the RSA are compared with results of the classical SA. The numbers of optimization iterations could be effectively reduced by the RSA.

• Journal of the Korean Society of Combustion
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• v.17 no.3
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• pp.30-45
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• 2012

An existing unit of power plant is considered to refurbish it for possible application of carbon capture and storage(CCS). Conceptual design of the plant includes basic considerations on the national and international situation of energy use, environmental concerns, required budget, and time schedule as well as the engineering concept of the plant. While major equipment of the recently upgraded power plant is going to be reused, a new boiler for air-oxy fired dual mode operation is to be designed. Cryogenic air separation unit is considered for optimized capacity, and combustion system accommodates flue gas recirculation with multiple cleaning and humidity removal units. The flue gas is purified for carbon dioxide separation and treatment. This paper presents the background of the project, participants, and industrial background. Proposed concept of the plant operation is discussed for the possible considerations on the engineering designs.

• Transactions of the Korean Society of Automotive Engineers
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• v.22 no.2
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• pp.76-82
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• 2014

In this paper, an optimal power distribution algorithm is proposed for the small electric vehicle with front in-line and rear in-wheel motors. First, it is assumed that the vehicle driving torque and velocity are given conditions. And, an optimal problem is defined that finding the front and rear motor torques which minimizes the battery power. From the above optimization problem, the optimized front-rear motor torque distribution map is obtained. And, the vehicle simulations are performed to verify the performance of the optimal power distribution algorithm which is proposed in this study. The simulations are performed based on the federal urban driving schedule for two cases which are constant ratio power distribution, and optimal power distribution. From the simulation results, it is found that the optimal power distribution shows the 6.3% smaller battery energy consumption than the constant ratio power distribution.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.416-416
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• 2000

The Systems Engineering, as a methodology for engineering and management of today's ever-growing complex system, is a comprehensive and iterative problem-solving process. The process centers on the analysis and management of the stakeholders'needs throughout the entire Life-cycle of a system and searches for an optimized system architecture. There are many essential needs and requirements to be met when a system development task is carried out. Systems Engineering Management PLan(SEMP), as a specification for system development process, must be established to satisfy constraints and requirements of stakeholders successfully and to prevent cost overrun and schedule delay. The paper suggests a systematic SEMP development process and demonstrates a data model and schema for computer-aided systems engineering software, RDD-100, for use in the development and management of SEMP These are being applied to the systems engineering technology development task for the next-generation high-speed railway systems in progress.

• IE interfaces
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• v.22 no.4
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• pp.302-311
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• 2009

It's very important to make an effective and optimized production schedule for the small-to-medium-sized factory which have high-variety low-volume manufacturing properties. And now people say that MES is very useful to make scheduling more effectively. But for small-to-medium-sized factory, it is very difficult to build MES system because of fewer infrastructures in the factory, and more to keep it's continuous maintenance and improvement. Therefore it is more important to systematize the production scheduling generation using simpler and easier tools like EXCEL sheet. And it will be needed a new method to make simple MES construction for more efficient production scheduling. This paper proposes the method which can build simple MES easily using a tool of EXCEL VBA for a small-to-medium-sized factory, and introduces an applied case by the proposed method and EXCEL VBA.

• Journal of the Korea Society of Computer and Information
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• v.25 no.3
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• pp.57-64
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• 2020

Today, with the development of information technology, hospitals are actively researching hospital information systems that are not limited by time and space to integrate mobile computing technology into the medical field to manage the bulk data of medical information. Nevertheless, most hospitals still spend a lot of time and effort creating manual schedules. In this paper, we studied an optimization model for organizing nurses' shift work and constructed an automated nurse-type job organization system. For nurses working in S hospital, information data, requirements and constraints of nurses were constructed. By applying this, we proposed an optimized scheduling method and built a web-based platform used by head nurses and a mobile app platform used by general nurses to enable real-time interchange and sharing around web servers. Therefore, through the developed nurse needs type automated system, the head nurses will increase the convenience of the nurses to organize the work every month, and general nurses will help them to work more accurately through personal schedule management. It is also expected to increase work efficiency by sharing work schedules among nurses.

• Journal of Aerospace System Engineering
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• v.12 no.4
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• pp.35-48
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• 2018

The space qualification has to be conducted by a high level of screening to ensure the design margin of devices, materials, manufacturing processes, units, modules, and subsystem or system. The space qualification according to traditional test standards proposed by US military, NASA and ESA involve high cost and tight schedule due to their conservative requirements. It is necessary to develop a space qualification guideline that is cost-efficient and schedule-optimized for the development of domestic satellites. In this study, as a basic research to develop the space qualification guideline, the articles related to space qualification in test standards document released from military and space agency have been investigated. We are planning to utilize the results as a basic database for establishing the independent tailored space qualification guideline.