• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.22 no.9
• /
• pp.1220-1227
• /
• 2018

Avionics electronic equipment refers to the electronic equipment installed on an aircraft. Failure of avionics equipment can have a significant impact on aircraft operations as well as threaten the safety of pilots and passengers. Therefore, avionics electronic equipment is required to have higher reliability and safety than electronic equipment used for other purposes. Avionics equipment must consider various component selection and system design to meet reliability and safety-related requirements from the initial design stage. In this paper, we describe safety, reliability performance analysis method of avionics equipment, and introduce various design improvement methods that can be performed to meet safety requirement performance. Finally, the safety performance of the improved avionics equipment was reanalyzed and compared with the value before the improvement, the validity of the proposed design change was verified.

• Journal of the Korean Society for Precision Engineering
• /
• v.20 no.2
• /
• pp.94-103
• /
• 2003

In case of environment requiring safety such as human body and requiring flexible shape, a conventional mechanical actuator system does not satisfy requirements. Therefore, in order to solve these problems. a research of various smart material such as EAP (Electro Active Polymer), EAC (Electro Active Ceramic) and SMA (Shape Memory Alloy) is in progress. Recently, the highest preferring material among various smart material is EP (Electrostictive Polymer), because it has very fast response time, powerful force and large displacement. The previous researches have been studied properties of polymer and simple control, but present researches are studied a polymer actuator. An EP (Electostrictive Polymer) actuator has properties which change variably ils shape and environmental condition. Therefore, in order to coincide with a user's purpose, it is important not only to decide a shape of actuator and mechanical design but also to investigate a efficient controller. In this paper, we constructed the control logic with an adaptive fuzzy algorithm which depends on the physical properties of EP that has a dielectric constant depending on time. It caused for a sub-actuator to operate at the same time that a sub-actuator system operation increase with a functional improvement and control efficiency improvement in each actuator, hence it becomes very important to manage it effectively and to control the sub-system which Is operated effectively. There is a limitation on the management of Main-host system which has multiple sub-system, hence it brings out the Multi-Vehicle Control process that disperse the task efficiently. Controlling the multi-dispersion system efficiently, it needs the research of Main-host system's scheduling, data interchange between sub-actuators, data interchange between Main-host system and sub-actuator system, and data communication process. Therefore in this papers, we compared the fuzzy controller with the adaptive fuzzy controller. also, we applied the scheduling method for efficient multi-control in EP Actuator and the algorithm with interchanging data, protocol design.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.12 no.3
• /
• pp.401-408
• /
• 2001

This paper shows the design, fabrication and performance analysis of VCO which plays a major role in 5.8 GHz RF module for ITS. The design specifications of the VCO are determined on the basis of 5.8 GHz RF modul performance requirements. The design parameters are optimized through ADS simulation tool. The operating characteristic and performance analysis of the implemented VCO based on the design parameters are accomplished. The frequency variations according to the voltage change(0 ~5 V) of varactor diode are from 5.42 GHz to 5.518 GHz and the power level is 6.5 dBm. The second harmonic suppression are -21.5 dBc at 5.51 GHz and the phase noise characteristics are -83.81 dBc at 10 kHz offset frequency. The implemented VCO is available to not only DSRC and also, 5.8 GHz other systems.

• The Journal of Information Technology
• /
• v.1 no.1
• /
• pp.155-172
• /
• 1998

Electronic commerce is more than just handling purchase transactions and funds transfers over the internet. Despite electronic commerce's past roots in transactions between large corporations, banks, and other financial institutions, the use of the internet as a way to bring electronic commerce to the individual consumer has led to a shift in viewpoint. Over the past few years, both the press and the business community have increased their focus on electronic commerce involving the consumer Electronic commerce includes the tasks that support the buying and selling of goods and services, and interactions among those tasks. Electronic commerce enables companies to close stores, reduce inventory requirements, and distribute products over the internet. Electronic commerce can simplify communication and change relationships The economics of electonic commerce is concernec with a new market whose delivery and communication infrastructure happens to be the internet. The economics of electronic commerce focuses on markets whose transactions are facilitated by communications networks and delivery systems. However, any digital communications media will soon be capable of supporting virtual transactions In the electronic marketplace, including telephone wires, cables, microwaves, and satellites. Thus, electronic commerce can offer your company both short-term and long-term befits. moving business practices, such as ordering, invoicing, and consumer support, to network-based systems can also reduce the paperwork involved in business-to-business transactions. This study conducted a study on economic effects of electronic commerce

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.44 no.1
• /
• pp.70-79
• /
• 2016

Satrec Initiative successfully developed a high-resolution electro-optical camera system, EOS-D Ver.1.0. EOS-D Ver.1.0 is the main payload of DubaiSat-2 and Deimos-2, which are developed based on the SI-300 platform of Satrec Initiative. After the launch and early operation (LEOP) of DubaiSat-2 and Deimos-2, we performed refocusing for the telescope of EOS-D Ver.1.0 to compensate for the dimensional change of its metering structure by moisture out-gassing. Before and after refocusing, we conducted the performance evaluation of thermal control system(TCS) for EOS-D Ver.1.0 using the in-orbit telemetry data. The evaluation showed EOS-D Ver.1.0 was under well-controlled thermal environment, which demonstrates TCS was designed and developed to meet all requirements.

• Journal of Korea Society of Industrial Information Systems
• /
• v.24 no.2
• /
• pp.65-80
• /
• 2019

With the advent of the ICT-based 4th industrial revolution, the convergence of the manufacturing industry and ICT seems to be the new breakthrough for achieving the company's competitiveness and play a role on the key element for accelerating the revival of the manufacturing industry. When the smart factory is implemented, each plant can analyze the quantity of data collected, build the data-driven operation systems which can make decisions, and ultimately discover the correlation among many events in the manufacturing sites. As the customers' needs become diversified more and more, it is required for the company to change its operating method from large quantity batch production systems to customizable and flexible manufacturing systems. For performing this requirements, it is essential for the company to adopt the smart factory. Based on technology acceptance model (TAM), this study investigates the factors influencing continuous use intention and switching intention of the smart factory. To do so, a questionnaire survey is conducted both online and offline. 122 samples are used for the study analysis. The results of this study will provide many implications with many researchers and practitioners relevant smart factories.

• Membrane and Water Treatment
• /
• v.14 no.2
• /
• pp.85-93
• /
• 2023

Membrane separation is widely used for several applications such as water treatment, membrane reactors and climate change. Cross-linked organic-inorganic hybrid polyvinylidene fluoride (PVDF) / Tetraethyl orthosilicate (TEOS) was adopted for the preparation of optimized hollow membrane (HFM) for membrane distillation or other low pressure separators for mechanical properties and permeability under varying pretreatment schemes. HFMs were prepared on semi-pilot membrane fabrication system. Novel adopted post-treatment schemes involved soaking in glycerol, magnesium sulphate (MgSO₄), sodium hypochlorite (NaOCl), and isopropanol for different durations. All fibers were characterized for morphology using a scanning electron microscope (SEM), surface roughness using atomic force microscope (AFM), elemental composition by examining Energy Dispersive Spectroscopy (EDS), water contact angle (CA°) and porosity. The performance of the fibers was evaluated for pure water permeation flux (PWF). Post-treatment with MgSO₄ gave the highest both tensile modulus and flux. Assessment of properties and performance revealed comparable results with other organic-inorganic separators, HF or flat. In spite of few reported data on post treatment using MgSO₄ in presence of TEOS, this proves the potential of low cost treatment without negative impact on other membrane properties. The flux is also comparable with hypochlorite which manifests substantial precaution requirements in actual industrial use.The relatively high values of flux/bar for sample treated with TEOS, post treated with MgSO₄ and hypochlorite are 88 and 82 LMH/bar respectively.

• The Korean Journal of Archival Studies
• /
• no.18
• /
• pp.3-36
• /
• 2008

Despite the institutional, organizational, and technological advances in the level of national records management that has occurred during the past several years, there has been no significant change in the condition of records management within individual public institutions, which may be an outset for records management. In order to begin the advance in national records management with overall innovation in records management by public institutions, it is necessary to distinctly set up the direction of innovation and a project to carry out. Also, a person in charge of records management, who is supposed to lead records management in each institution, should share the directions and projects. Against this backdrop, this study aims to define "the evaluation of records management" as a vehicle to establish a common goal for the innovation of records management and the role of a person in charge of records management as well as to develop evaluation indicators that might be applicable to all public institutions. With this aim, the study drew requirements of records management from domestic and overseas cases in the evaluation of records management conditions as well as the laws and standards of records management, and a roadmap for national records management innovation. Then, the study developed evaluation indicators by classifying the requirements according to three areas involving an organizational environment, records management job, and records management in the offices that create and file their own documents. The organizational environment area is concerned with the evaluation of the records management policy and the responsibility of an institution, and the evaluation of human resources and physical environment. The records management business area includes the measurement of the level of jobs, such as the records creation control conducted by the records management authority of each institution, the management of records schedules, the accession, preservation, and appraisal of records and their service, and the monitoring of records management. The area of records management in the offices is composed of the creation, registration, arrangement, and transfer of records as they are intended to be used during the monitoring of records management conditions. The study made it possible to measure all evaluation indicators with a quantitative evaluation method by clearly proposing the standard for objective and accurate evaluation.

• Journal of Engineering Education Research
• /
• v.9 no.3
• /
• pp.49-61
• /
• 2006

The objective of this study was to propose a new framework for the creative engineering in the product family design coursework. The idea of product family design is a good solution to fulfill customer's requirements and to respond quickly for the technology change. Mass customization based on product family and product platform is a new paradigm with variety and customization through flexibility and quick responsiveness. In this study, the subjects of product family, product platform, product family map, platform leveraging strategy, morphological matrix and module based product family design were reviewed and presented. A new idea generation scheme utilizing SCAMPER method was combined with the morphological matrix approach. For the effective product family and platform design, creative efforts and approaches were utilized and implemented in the coursework process. This will help students to develop creative thinking and approaches in the engineering problem solving.

• Journal of the Korean Society of Hazard Mitigation
• /
• v.8 no.4
• /
• pp.17-22
• /
• 2008

Including heat wave, Climate change caused 150,000 casualty in 2000 and heat waves are meteorological events that pose a serious threat to human health. A heat wave is defined as "a period of abnormally and uncomfortably hot and usually humid weather". There is a need for the prevention of health effects due to weather and climate extremes. This study intends to propose the necessity of Response System to correspond to extreme heat. And this research focused on Cooling Center manual of facility and maintenance for extreme heat disaster. It would be useful to be planned based on community and to be taken a role as an E.O.C.(Emergency Operating Center). As a conclusion elderly watching system and the requirements regional cooling center facility was proposed.