• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.37 no.4
• /
• pp.569-579
• /
• 2013

Robot control and image processing using a smartphone and Wi-Fi communication is introduced. The robot has a wheel and quadruped mechanism that is transformed according to the environment and is mainly used for drug bottle delivery. The captured image on the camera is transmitted to the smartphone in the form of stream data, and the image data is processed in the smartphone to enable the robot to identify an object and to control the robot itself. A network was constructed so that only image data from the stream data was used, and an image processing scheme to identify the drug bottle and deliver it to a person using a robot arm is also presented. In this study, image processing techniques and algorithms were purely implemented on a smartphone with considerable computational power and multiple functions rather than a computer, which contributes to the intelligence and miniaturization of the robot system.

• Journal of the Computational Structural Engineering Institute of Korea
• /
• v.20 no.6
• /
• pp.751-759
• /
• 2007

We have developed several methods for the optimization problem having large-scale and highly nonlinear system. First, step by step method in optimization process was employed to improve the convergence. In addition, techniques of furnishing good initial guesses for analysis using sensitivity information acquired from optimization iteration, and of manipulating analysis/optimization convergency criterion motivated from simultaneous technique were used. We applied them to flow control problem and verified their efficiency and robustness. However, they are based on quasi-Newton method that approximate the Hessian matrix using exact first derivatives. However solution of the Navier-Stokes equations are very cost, so we want to improve the efficiency of the optimization algorithm as much as possible. Thus we develop a true Newton method that uses exact Hessian matrix. And we apply that to the three-dimensional problem of flow around a sphere. This problem is certainly intractable with existing methods for optimal flow control. However, we can attack such problems with the methods that we developed previously and true Newton method.

• Journal of Conservation Science
• /
• v.26 no.3
• /
• pp.229-245
• /
• 2010

The pupose of this study was to identify the material characteristics, firing environments and making techniques for the jar coffins from the Oryangdong kiln site and the Ungokdong tomb site in Naju. All jar coffins had very similar physical, mineralogical and geochemical characteristics, although it was excavated from the different sites. The wall thickness of the jar coffins was about 2.3 to 5.3 cm. Under the microscopy, the jar coffins include a large quantity of various quartz with some microcrystalline and showed partly orthoclase and biotite. It is presumed that the mineral sherds added to maintain the thick wall and to control the percentage of contraction during drying and firing of jar coffins and it has contained about 11.4 to 19.8 %. Firing temperature of the jar coffins is estimated as 1,000 to $1,150^{\circ}C$. Also, all jar coffins and soils show similar geochemical behavior of elements and clay-mineralization degree within the site. This indicates making that the soil is probable to be a raw material of the jar coffins. But it shows different characteristics in major elements of soils which is collected at the kiln floor and the trench region of the Oryangdong kiln site because of the lack of quartz and feldspar in the soils. Therefore, it can use of the jar coffins making clay, if it goes through a simple special process such as mixing temper.

• Korean Journal of Construction Engineering and Management
• /
• v.8 no.4
• /
• pp.128-136
• /
• 2007

As the international-level concern has been focused on the environmental sustainability in recent years, many researches emphasized the needs for methods and techniques that would facilitate sustainability assessment at the various project level interfaces. As part of methods and techniques to facilitate sustainability assessment, this paper provides 'Computerized Waste Management Performance Evaluation Tool' for the purpose of assessing the level of management system in dealing with the onsite construction wastes. This tool applies twenty-three waste management performance factors for the purpose of evaluating the level of waste management performance by scoring those factors which were identified in the previous research. These twenty-three factors are classified into four categories: manpower, material, method, and management based on their characteristics. In order to quantitatively evaluate the effectiveness of waste management performance, the levels of actions executed in a site by each waste management performance factor were identified and their weight were analyzed throughout the expert interview and survey. Furthermore, an excel-based computerized tool was developed in order to facilitate the evaluation process. If this tool can be developed in more detail and be used as the method to control waste management at a project level for the future, it is expected that this tool can play an important role in the body of knowledge of environmental management in construction industry.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.28 no.spc
• /
• pp.1-10
• /
• 2022

As the volume of marine hazardous and noxious substances (HNSs) transported in domestic and overseas seas increases, the risk of HNS spill accidents is gradually increasing. HNS leaked into the sea causes destruction of marine ecosystems, pollution of the marine environment, and human casualties. Secondary accidents accompanied by fire and explosion are possible. Therefore, various types of HNSs must be rapidly detected, and a control strategy suitable for the characteristics of each substance must be established. In this study, the ground HNS spill experiment process and application result of detection algorithms were presented based on hyperspectral remote sensing. For this, styrene was spilled in an outdoor pool in Brest, France, and simultaneous observation was performed through a hyperspectral sensor. Pure styrene and seawater spectra were extracted by applying principal component analysis (PCA) and the N-Findr method. In addition, pixels in hyperspectral image were classified with styrene and seawater by applying spectral matching techniques such as spectral distance similarity (SDS), spectral correlation similarity (SCS), spectral similarity value (SSV), and spectral angle mapper (SAM). As a result, the SDS and SSV techniques showed good styrene detection results, and the total extent of styrene was estimated to be approximately 1.03 m². The study is expected to play a major role in marine HNS monitoring.

• Progress in Medical Physics
• /
• v.25 no.3
• /
• pp.185-192
• /
• 2014

The purpose of this study is to evaluate the results for the quality assurance through a statistical analysis on the output characteristics of linear accelerators belonging to Yeungnam University Medical Center by using the Shewhart-type chart, Exponentially weighted moving average chart (EWMA) chart, and process capability indices $C_p$ and $C_{pk}$. To achieve this, we used the output values measured using respective treatment devices (21EX, 21EX-S, and Novalis Tx) by medical physicists every month from September, 2012 to April, 2014. The output characteristics of treatment devices followed the IAEA TRS-398 guidelines, and the measurements included photon beams of 6 MV, 10 MV, and 15 MV and electron beams of 4 MeV, 6 MeV, 9 MeV, 12 MeV, 16MeV, and 20 MeV. The statistical analysis was done for the output characteristics measured, and was corrected every month. The width of control limit of weighting factors and measurement values were calculated as ${\lambda}=0.10$ and L=2.703, respectively; and the process capability indices $C_p$ and $C_{pk}$ were greater than or equal to 1 for all energies of the linear accelerators (21EX, 21EX-S, and Novalis Tx). Measured values of output doses with drastic and minor changes were found through the Shewhart-type chart and EWMA chart, respectively. The process capability indices $C_p$ and $C_{pk}$ of the treatment devices in our institution were, respectively, 2.384 and 2.136 for 21EX, 1.917 and 1.682 for 21EX-S, and 2.895 and 2.473 for Novalis Tx, proving that Novalis Tx has the most stable and accurate output characteristics.

• Journal of KIISE:Databases
• /
• v.30 no.6
• /
• pp.641-650
• /
• 2003

The eXtensible Markup Language(XML) is emerging as a standard format of data representation and exchange on the Internet. There have been researches about storing and retrieving XML documents using the relational database which has techniques in full growth about large data processing, recovery, concurrency control and so on. Since in previous systems same structure information and fundamental operation are used for processing of various kinds of XML queries, only some specific query can be efficiently processed not all types of query. In this paper, we propose a flexible query processing system. To process query efficiently, the proposed system analyzes regular path expression queries, and uses $\theta$-join operation using region numbering values to check ancestor-descendent relationship and equi-join operation using parent's region start value to check parent-child relationship. Thus, the proposed system processes efficiently XML regular path expressions. From the experimental results, we show that proposed XML query processing system is more efficient than previous systems.

• The Transactions of the Korea Information Processing Society
• /
• v.4 no.4
• /
• pp.1106-1120
• /
• 1997

In this paper,we prosent a new run-time support system for SR usitn POSIX threads (Pthreads),called SR/RTS +.SR supports a rich set of concurent programming techniques with multiple cincurrency control primit-ives Since the original RTS for SR uses its own thread management facility,it should be modifide to work on different computer systems.Furthermore,the run-time efficiency of the RTS should be considered in association with those different sytems.Thus,to portability and to guarantee the predictable run-time ef-ficiency,SR/RTS + is designed on the pthreads(POSIX Threads )which supports multiple threads of con-trol within a single POSIX process.Also, the SR compiler is modified to generate the codes appropriate for pthreads interface.SR/RTS + has been develped on Spare Workstation using pthreads library announced by Florida State University and tested with the SR verification suite distribute by the University of Arizona.

• 제어로봇시스템학회:학술대회논문집
• /
• 2003.10a
• /
• pp.174-179
• /
• 2003

Through the simultaneous localization and map building (SLAM) technique, a robot can create maps about its unknown environment while it continuously localizes its position. Grid maps and feature maps have been widely used for SLAM together with application of probability methods and POMDP (partially observed Markov decision process). But this approach based on grid maps suffers from enormous computational burden. Topological maps, however, have drawn more attention these days because they are compact, provide natural interfaces, and are easily applicable to path planning in comparison with grid maps. Some topological SLAM techniques like GVG (generalized Voronoi diagram) were introduced, but it enables the robot to decide only whether the current position is part of GVG branch or not in the GVG algorithm. In this paper, therefore, to overcome these problems, we present a method for updating a global topological map from the local topological maps. These local topological maps are created through a labeled Voronoi diagram algorithm from the local grid map built based on the sensor information at the current robot position. And the nodes of a local topological map can be utilized as the features of the environment because it is robust in light of visibility problem. The geometric information of the feature is applied to the extended Kalman filter and the SLAM in the indoor environment is accomplished. A series of simulations have been conducted using a two-wheeled mobile robot equipped with a laser scanner. It is shown that the proposed scheme can be applied relatively well.

• 제어로봇시스템학회:학술대회논문집
• /
• 2003.10a
• /
• pp.2087-2089
• /
• 2003

The presence of narrowband interference (NBI) in Direct-sequence code division multiple access (DS/CDMA) systems is an inevitable problem when the interference is strong enough. The improvement in the system performance employs by adaptive narrowband interference suppression techniques. Basically there have been two types of method for narrowband interference suppression estimator/subtracter approaches and transform domain approaches. In this paper the focus is on the type of estimator/subtracter approaches. However, the binary direct sequence (DS) signal, that acts as noise in the prediction process is highly non-Gaussian. The case of a Gaussian interferer with known in an autoregressive (AR) signal or a digital signal and also in a sinusoidal signal (Tone) that included in is paper. The proposed NBI suppression is presence in an adaptive IIR notch filter for lattice structure and more powerful by using a variable step-size algorithm. The simulation results show that the proposed algorithm can significantly increase the convergence rate and improved system performance when compare with adaptive least mean square algorithm (LMS).