• 전자통신동향분석
• /
• 제36권5호
• /
• pp.92-102
• /
• 2021

Owing to various restrictions in-field application, the low-speed, low-power-based industrial Internet-of-Things (IoT) network built in extremely harsh industrial environment sites requires multi-hop, channel hopping, and low-latency transmission characteristics. In the past, wired networks were used in industrial facilities; however, network technologies based on the Industrial IoT Network standard standardized for industrial applications, such as WirelessIO link, WirelessHART, SmartMesh, and eStar Link satisfy industrial requirements. Recently, the use of industrial IoT networks in industrial facilities has rapidly expanded. This paper covers the developments in industrial IoT network technologies and summarizes the major industrial IoT standard technologies that meets the requirements of industrial sites.

• 안전기술
• /
• 50호
• /
• pp.64-69
• /
• 2002

• 안전기술
• /
• 53호
• /
• pp.64-69
• /
• 2002

• 안전기술
• /
• 49호
• /
• pp.72-75
• /
• 2002

• 안전기술
• /
• 51호
• /
• pp.64-69
• /
• 2002

• 안전기술
• /
• 52호
• /
• pp.68-73
• /
• 2002

• Journal of Communications and Networks
• /
• 제15권1호
• /
• pp.87-101
• /
• 2013

In industrial applications, sensor networks have to satisfy specified time requirements of exchanged messages. IEEE 802.15.4 defines the communication protocol of the physical and medium access control layers for wireless sensor networks, which support real-time transmission through guaranteed time slots (GTSs). In order to improve the performance of IEEE 802.15.4 in industrial applications, this paper proposes a new traffic scheduling algorithm for GTS. This algorithm concentrates on time-critical industrial periodic messages and determines the values of network and node parameters for GTS. It guarantees real-time requirements of periodic messages for industrial automation systems up to the order of tens to hundreds of milliseconds depending on the traffic condition of the network system. A series of simulation results are obtained to examine the validity of the scheduling algorithm proposed in this study. The simulation results show that this scheduling algorithm not only guarantees real-time requirements for periodic message but also improves the scalability, bandwidth utilization, and energy efficiency of the network with a slight modification of the existing IEEE 802.15.4 protocol.

• 산업경영시스템학회지
• /
• 제40권3호
• /
• pp.49-58
• /
• 2017

The DQMS (Defence Quality Management System) is a certification system that manages participating companies to improve the quality of munitions. Since Korean Defense Specification (KDS) for DQMS certification that was established by adding military requirements based on the ISO quality standard, many companies complain that they should pay too much effort into the preparation process. However, it is hard to find helpful information on the preparation process because we have been only interested in the effect of DQMS acquisition. The purpose of this paper is to provide helpful information to companies preparing for DQMS certification. We surveyed the degree of difficulty and importance of the DQMS requirements from the companies with certification experience, and performed IDA (Importance-Difficulty analysis) by dividing the companies into the main contractor and the subcontractor. The result of IDA shows that there is a different recognition to the DQMS certification between main-contracting and sub-contracting companies. Subcontractor has more difficulties than main contractor in preparing the DQMS certification. In addition, we are able to identify the difficult and important requirements in the preparation process to the DQMS certification. Both main contractor and subcontractor have difficulty to the requirements related to configuration or validation such as 'customer controls configuration', 'configuration review shall be implemented' and 'design and development validation documentation.' The requirements related to customers are important to main contractor but the subcontractor regards difficult requirements as important ones. The result of this paper would be helpful to both the company preparing for DQMS and the munitions quality assurance agency.

• 대한산업공학회지
• /
• 제41권1호
• /
• pp.17-24
• /
• 2015

Mixed acceptance sampling plans for quantity of products in prepackages are widely used for compliance testing. To pass testing, random samples jointly comply with two legal requirements: (i) the average net content of an inspection lot shall be not less than the labelled quantity and (ii) the numbers of under-filled prepackages in a sample are less than or equal to permitted numbers. This paper discusses some drawbacks of the acceptance sampling plans and requirements recommended in OIML R87 (KS A 50087 translated by Korean) developed by the International Organization of Legal Metrology and evaluates the producer's and consumer's risks. In addition, problem of determining a target value in filling processes of prepackages under the OIML R87 requirements is addressed and illustrated with a numerical example.

• Industrial Engineering and Management Systems
• /
• 제15권3호
• /
• pp.215-223
• /
• 2016

Design of personnel teams has been studied from diverse perspectives; the most common are the people and systems requirements perspectives. All these point of view are linked, which is the reason why it is necessary to study them simultaneously. Considering this gap, a decision making model is developed based on factors, models, and requirements mentioned in the literature. The model is applied to a real case. The findings indicate that the Personnel Behavior Based Lean model (PBBL) can be converted into a decision making model for the selection of team members. The study is focused not only on the individual candidates' knowledge, skills, and aptitudes, but also on how the model considers the company requirements, conflicts, and the importance of each person to the project.