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Recently, corporations around the world have been making numerous efforts to innovate manufacturing due to intensified competition. These innovations in manufacturing can be characterized as “smart” manufacturing technology, and include Cyber Physical System(CPS), Internet of Things(IoT), big data, and cloud computing as applications of diverse information technologies. This study introduces research that has focused on Material Flow Cost Accounting(MFCA) in consideration of sustainability, targeting vehicle recycling factories, using an Modeling and Simulation(M&S) technique, which is one of the core elements of actualizing CPS among the core technologies in smart factory manufacturing. Specifically, this study describes the process from entering necessary data for a simulation to model creation to MFCA analysis, and verifies the applicability of the system using test examples.

To overcome limitations of existing single robots in search and rescue missions, a multi-scale cooperative robot system which consists of multiple robots of various sizes is developed. The resultant system is a hierarchical multi-scale cooperative robot which has a communication infrastructure based on an ACK packet scheduling method and a variant of the MapReduce framework. They effectively solve a network congestion problem during communication between robots.

This paper presents the application of M2M communication technology for automated intelligent manufacturing system. M2M technology allows exchanging and gathering information between sensors and controllers during collaborative machining process and motion control.

In this paper, for the usefulness to the performance improvement of the photovoltaic (PV) array and inverter and their design, construction, and post-operation and management, which can become the key elements for the future PV system, the performance characteristics of the 50kW grid-connection PV system in Korea was evaluated and analyzed.

Micromachining of internal features by electrochemical machining (ECM) is investigated. By controlling pulse conditions and using a customized tool electrode, micro features were machined on the side wall of a micro hole. In micro ECM, longer pulse on-time enlarges the side gap. A reverse tapered hole and a barrel-shape hole were fabricated through pulse duration control. Micro cavity was machined by controlling the pulse duration and machining time in similar manner. A micro disk-shape electrode was used to machine microgroove inside the hole, which is similar to turning lathe process.

Carbon nanomaterials such as carbon nanotubes and carbon nanofibers (CNFs) have been intensively investigated for various nanoelectronic applications due to their superb properties, good stability, and high aspect ratio. There have been many efforts to develop flat panel displays, light sources, and backlight units by using carbon nanomaterials. For wider applications, carbon nanomaterials often need to be cut, leveled, patterned, and figured. A reliable and precise micro-machining process, electrical discharge machining (EDM), was investigated in depth as a very neat method for the effective and multifunctional engineering of carbon nanomaterials. In the present study, the mechanisms of the EDM engineering of carbon nanomaterials are systematically examined, and the advanced field emission applications derived from the EDM method are presented.

Carbon nanotubes (CNTs) were synthesized in atmospheric pressure microwave plasma torch in the mixture of argon, methane and hydrogen on the silicon substrate with SiO2 overlayer and a thin top iron film serving as a catalyst. This deposition technique is unique because of its simplicity and high CNT growth rate but it is still under investigation as concerns exits around its reproducibility. CNTs were deposited with the future prospect of their applications or further characterization that might require CNTs in the form of suspension or powder. One of the research directions includes measurements of CNT electrical properties such as their current-voltage (I-V) characteristics. Preparation of solutions with well dispersed CNTs was studied using various liquids (distilled water, ethyl alcohol) and ultrasonication. Dried drops of these solutions were investigated by scanning electron microscopy (SEM) and atomic force microscopy (AFM) in order to assess CNT appearance and dispersion. Electrical measurement chips with gold electrodes were prepared by electron lithography. CNTs were placed on the chips by dropping their solution and the I-V characteristics may be measured by contacting the electrodes bridged by CNTs.

The amount of oxygen, which is used as an additive gas in preparing ZnO films by RF magnetron sputtering, has been changed during deposition in the range of O/sub 2//(Ar+O/sub 2/) = 10-90 % and its influence on film properties has been examined. X-ray diffraction (XRD) and atomic force microscope (AFM) studies present an optimal condition for oxygen addition at which ZnO films with desirable properties, such as highly preferred [002] orientation, excellent crystallinity, and smooth film surface, can be grown. The effect of electric bias (DC) applied to the substrate (from -80 V to +80 V) has also been analyzed in terms of the crystal quality and surface roughness of ZnO films. In addition, film bulk acoustic resonators (FBARs) with configuration of Al/ZnO/Al/Si(111) are fabricated and the influence of electric bias on their frequency response characteristics. The result shows that DC substrate biasing may improve the crystal quality of deposited ZnO films, and consequently enhance the electromechanical coupling capability of ZnO-based FBARs.

A two-step deposition method using RF reactive magnetron sputtering is proposed to obtain AlN thin films of high quality for film bulk acoustic resonators (FBARs). The 1/sup st/ deposition step is focused on lowering the surface roughness of the AlN films. In the 2/sup nd/ deposition step, the RF power and the working pressure are controlled to enhance the c-axis preferred growth of the AlN films. It is seen by monitoring the X-ray diffraction (XRD) spectra that the films deposited by the two-step method reveal an improved c-axis preferred orientation. Atomic force microscopy (AFM) images show that the surface roughness of the films is drastically reduced by adopting two-step deposition. It is also found, from the measurement of the frequency response characteristics of the AlN-FBARs, that the devices based on AlN films prepared using the two-step method reveal better device performance in return loss and electro-mechanical coupling coefficient (k/sub t//sup 2/).

To control the production schedule for mold making, it is important to collect the actual results of machining operations, yet machine operators seldom record the results. Some die and mold shops have constructed a system which interfaces with NC controllers and which identifies the status of the machining operation from signals. This method depends totally on the NC controller and requires higher installation cost. We propose a method that is independent of the NC controller. This method uses a low-cost PC camera and image processing technology; and it has one algorithm for tracking moving objects and another for detecting scene changes. To demonstrate the validity of the proposed method, we applied it to both attended and unattended NC machining.

In this paper, the localization of a mobile robot using images of a moving target is introduced. Typical objects are stored in the database for the localization of the mobile robot. With a fixed camera, a perspective camera model and a given object database, an image frame can provide the pose (distance and orientation) of the object with respect to the camera. Utilizing the consecutive image frames and motion estimation technology, the relative pose of the object with respect to the camera can be obtained accurately; and during the process, calibration of camera with respect to the world frame, i.e. localization of a mobile robot, is gradually performed. This localization scheme is demonstrated by the experiments.