• Journal of international Conference on Electrical Machines and Systems
• /
• v.1 no.2
• /
• pp.46-52
• /
• 2012

This paper proposes a novel single-phase ac-ac converter topology based on the Z-source concept. The converter provides buck-boost function and plays the role of frequency changer. Compared to the traditional ac-dc-ac converter, it uses fewer devices, realizes direct ac-ac power conversion, and has a simpler circuit structure, so as to have higher efficiency and better circuit characteristics. Compared to the traditional matrix converter, it provides a wider voltage regulation range. The circuit topology, operating principle, control method and simulation results are given in this paper, and the rationality and feasibility is verified.

• Particle and aerosol research
• /
• v.6 no.3
• /
• pp.123-129
• /
• 2010

As the indoor activity increases in recent years, the indoor air quality becomes more important. One of the major contaminants in office space is the copy machines and the laser based printers. These devices usually emit nano-particles and chemical species that may give some health effect. The amount of particles generated by the printers and copy machines depend on printer models, printing speed, toners, papers, humidity and so on. To evaluate the emission rate of nano-particles from Laser Printers, the mass concentration measurement method has been used (BAM, 2004). However, the mass concentration measurement method for nano-particles is tedious and time consuming. Therefore, for the development of a new nano-particle counting method, the nano-particle emission characteristics and size distributions are evaluated.

• Journal of international Conference on Electrical Machines and Systems
• /
• v.2 no.4
• /
• pp.454-459
• /
• 2013

The authors study a novel type of elevator emergency stop device which enables to soften impact force at an emergency halt. A new structure of emergency stop devices has been already proposed by our laboratory and also its characteristics has been already proposed by our laboratory and also its characteristics has been shown by digital simulations[1]. In order to confirm the actual effects of our proposed emergency stop device, we have made up a simulator having the same characteristics as the conventional emergency stop device to accomplish the experiments from now on. In this paper, this process is introduced.

• IE interfaces
• /
• v.15 no.4
• /
• pp.364-373
• /
• 2002

This paper developed an operating software for the manufacturing cell of a model plant. The model plant, which was manufactured by Fishertechnik, consists of an assembly cell, a machining cell, and supplementary material handling equipments. Each I/O module of the model plant communicates with the INTERBUS controller devices via High-level Language Interface(HLI). The machining center has two machining cells, which consists of 4 machines respectively, two 3-axis portal transporters, and a rail guided vehicle(RGV). The Petri-Net was used to investigate the dynamics of each machining cell, e.g., the relation of material handling equipments and machines. The operating software was analyzed and designed by Object Oriented Technique. The software was implemented using Delphi 3.0 under Windows 95/NT operating system.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.17 no.12
• /
• pp.3398-3415
• /
• 2023

Internet-of-Things (IoT) is an emerging technology that interconnects millions of small devices to enable communication between the devices. It is heavily deployed across small scale to large scale industries because of its wide range of applications. These devices are very capable of transferring data over the internet including critical data in few applications. Such data is exposed to various security threats and thereby raises privacy-related concerns. Even devices can be compromised by the attacker. Modern cryptographic algorithms running on traditional machines provide authentication, confidentiality, integrity, and non-repudiation in an easy manner. IoT devices have numerous constraints related to memory, storage, processors, operating systems and power. Researchers have proposed several hardware and software implementations for addressing security attacks in lightweight encryption mechanism. Several works have made on lightweight block ciphers for improving the confidentiality by means of providing security level against cryptanalysis techniques. With the advances in the cipher breaking techniques, it is important to increase the security level to much higher. This paper, focuses on securing the critical data that is being transmitted over the internet by PRESENT using key-based dynamic S-Box. Security analysis of the proposed algorithm against other lightweight block cipher shows a significant improvement against linear and differential attacks, biclique attack and avalanche effect. A novel key-based dynamic S-Box approach for PRESENT strongly withstands cryptanalytic attacks in the IoT Network.

• Journal of Biosystems Engineering
• /
• v.21 no.3
• /
• pp.306-314
• /
• 1996

A seeder monitoring system was developed to solve the problems of mis-sowing and tube clogging in direct seeding machines, which have been one of the factors that reduce the performance of sowing operations. The system consisted of photo sensors, air nozzles, an air compressor, and a one-chip micro-computer based controller. The system was also equipped with the devices that perform the functions of self-checking and intermittent air injection for cleaning seed tubes. The performance of the system was tested in the laboratory and field. Using the well-cleaned rice seed, the average time for checking the mis-sowing was 1.37 seconds in the field and 1.2 seconds in the laboratory without any malfunction. Overall evaluation of the system indicated that the system can be utilized for seeding machines not only for paddies but beans and corns.

• Proceedings of the Korean Society for Agricultural Machinery Conference
• /
• 1993.10a
• /
• pp.1302-1311
• /
• 1993

In the 90 years or so since the beginning of the 20 th century , orchard growing and agricultural fields in Japan have undergone considerable change in terms of production volume, a seen in Fig. 1. as this change in volume progressed, sorting and packing machines have also grown from the first wooden tools, almost too simple to be called " machines" into sophisticated devices that bring together diverse technologies such as machinery , electronics, and optics. Nowadays, Japan/s agricultural industry is facing unprecedentedly serious labor shortage and the rapid aging of its experienced growers and producers, In additions, Japan has changed from a society oriented towards high-volume production and consumption to a more selective society which prefers smaller volume with the tastes of naturally ripended produce. With consumer trends changing there is a new demand on the part of growers for equipment that can not only measure the external quality of produce , but can measure inte nal quality as well.

• Journal of international Conference on Electrical Machines and Systems
• /
• v.1 no.2
• /
• pp.98-104
• /
• 2012

This paper presents a novel transformer isolated parallel connected full-bridge dc-dc converter using recently developed trans-Z-source network. Unlike the traditional voltage -fed or current-fed converters, the proposed converter can be open- and short-circuited without damaging switching devices. Therefore, the desired buck and boost function can be achieved and the converter reliability can be greatly improved. A 6 kW prototype dc-dc converter is built and tested to verify performances of the proposed converter.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.6 no.1
• /
• pp.13-19
• /
• 2007

The spring is an important mechanical parts to improve the functions of precision machines, automobiles, ships, industrial machines, and IT devices etc.. The hinge mechanism for LCD monitors is very important to support and maintain the proper position of monitor panel, and the tension spring which is a major parts of hinge mechanism plays a significant roll to provide the supporting force positioning the monitor panel. In this paper, an analysis and experiment were carried out to investigate the fatigue characteristics of the tension spring of hinge mechanism, such as hardness test, fatigue test and fractography analysis. As a result of this study the SWPB with heat treatment and shot peening was found to have the optimal design conditions of tension spring for LCD monitor hinge mechanism.

• Journal of international Conference on Electrical Machines and Systems
• /
• v.3 no.3
• /
• pp.248-251
• /
• 2014

As more vehicles become equipped with advanced electronic control systems, more consideration is needed with regards to automotive safety issues related to the effects of electromagnetic waves. Unwanted electromagnetic waves from the antenna, electricity and other electronic devices cause the performance and safety problem of automotive components. In general, Power Integrity and Signal Integrity analysis have been widely used, but these analyses have stayed PCB level. PCB base analysis is different from radiated emission TEST condition so its results are used just for reference. This paper proposes EMC optimization technology using module level 3-dimensional radiation simulation process closed to fundamental test conditions. If module level EMC analysis, which is proposed in this study, is applied to all automotive electronics systems, unexpected EMC noise will be prevented.