• Composites Research
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• v.33 no.2
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• pp.68-75
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• 2020

Recently, the use of TiO₂ as a phtocatalyst has been diversely investigated due to its excellent durability performance and high photocatalytic reaction efficiency. Active researches have particularly focused on the development of TiO₂-incorporated cementitious composites in order to remove the atmospheric pollutants. Furthermore, the potential utilization of TiO₂-incorporated cementitious composites as road accessories such as tunnels, road median separators and soundproof walls in the form of tiles, blocks and structural components has been widely examined. In this regard, a thorough understanding on the material characteristics of TiO₂-incorporated cementitious composites should be preceded. The present overview article, therefore, revisits previous studies of TiO₂-incorporated cementitious composites and summarizes their various physicochemical properties and atmospheric pollutants removal performance.

• Journal of the Society of Naval Architects of Korea
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• v.28 no.2
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• pp.1-11
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• 1991

A hull form for an Aframax tanker whore form parameters cover the values of $C_B{\simeq}0.8,\;L/B{\simeq}5.5\;and\;B/d{\simeq}3.5$ has been developed by applying a composite stern frameline concept and its excellent performance has been evaluated through a series of model tests at the Korea Research Institute of Ships and Ocean Engineering. The tests showed that this concept was very much promising in the cases of wide breadth and shallow draught vessels and suitably applicable to the stern frameline shape. For the comparison, a hull form developed by Japanese 'H' yard has been selected and the performances of two hull forms were evaluated by model tests and theoretical calculations. The comparison shows that Daewoo hull form requires less effective power by 10% and less delevered power by 5-6% at both full load and ballast conditions. In addition, it is suggested that Hushes method can give better correlationthan Froude method because the full scale resistance extrapolated by Froude method would be very much optimistic in case of the hull form with very low value of form factor.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.11
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• pp.221-228
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• 2014

The color and shape of the tongue reflect the physiological and clinico-pathological condition of the body. Recently, various tongue image acquisition devices have been developed for accurate diagnosis based on quantitative and objective tongue features. Since a color information is essential for tongue diagnosis, the performance of an illuminator is very important for the tongue image acquisition device. In this study, we developed an indirect illumination, which is possible to improve a homogeneity of light intensities on the tongue surface, and evaluated its performances. In order to realize the indirect illumination (II), a semi-ellipsoidal solid structure (SESS) for the light reflex was located in the system, and two high-brightness white LEDs were placed for illuminating the areas under frontal camera in the SESS. The tongue surface was illuminated by reflected light from the SESS. The light homogeneity induced by three different illuminations including the II was evaluated by calculating coefficient of variation (CV) of illuminance of five regions. The II showed less than 0.01 of CV and the direct illumination (DI) and the direct illumination with a light diffusion plate (DILDP) showed 0.16 and 0.13, respectively. The reflexed pixel ratios of tongue phantom images show 5.76%, 4.22%, 1.79% for the DI, the DILDP and the II, respectively. The homogeneity of a tongue phantom was evaluated by calculating CV of mean pixel values of six different tongue regions, and showed less than 0.06 in the II. If the II technique apply to tongue diagnosis system, it is expected to improve diagnostic accuracy in clinic.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.32 no.2
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• pp.163-171
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• 2014

Based on the GPS/IMU integration, the car navigation has unstable conditions as well as drastically reduces accuracies in urban region. Nowadays, many cars mounted the camera to record driving states. If the ground coordinates of street furniture are known, the position and attitude of camera can be determined through SPR(Single Photo Resection). Therefore, an estimated position and attitude from SPR can be applied measurements in Kalman filter for updating errors of navigation solutions from GPS/IMU integration. In this study, the GPS/IMU/SPR integration algorithm was developed in loosely coupled modes through extended Kalman filters. Also, in order to analyze performances of GPS/IMU/SPR, simulation tests were conducted in GPS signal reception environments and the GCPs (Ground Control Points) distributions. In fact, the position and attitude gathered from GPS/IMU/SPR integration are more precise than the position and attitude from GPS/IMU integration. When IPs (image points), corresponded to GCPs, were concentrated in the center of image, the position error in the optical axis respectively increased. To understand effects from SPR, we plan to carry additional test on the magnitude of GCP, IP and initial exterior orientation errors.

• Proceedings of the KOSOMBE Conference
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• v.1996 no.05
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• pp.315-319
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• 1996

We have developed a prototype patient monitoring system including module-based bedside units, interbed network, and central stations. A bedside unit consists of a color monitor and a main CPU unit with peripherals including a module controller. It can also include up to 3 module cases and 21 different modules. In addition to the 3-channel recorder module, six different physiological parameters of ECG, respiration, invasive blood pressure, noninvasive blood pressure, body temperature, and arterial pulse oximetry with plethysmogaph are provided as parameter modules. Modules and a module controller communicate with up to 1Mbps data rate through an intrabed network based on RS-485 and HDLC protocol. Bedside units can display up to 12 channels of waveforms with any related numeric informations simultaneously. At the same time, it communicates with other bedside units and central stations through interbed network based on 10Mbps Ethernet and TCP/IP protocol. Software far bedside units and central stations fully utilizes gaphical user interface techniques and all functions are controlled by a rotate/push button on bedside unit and a mouse on central station. The entire system satisfies the requirements of AAMI and ANSI standards in terms of electrical safety and performances. In order to accommodate more advanced data management capabilities such as 24-hour full disclosure, we are developing a relational database server dedicated to the patient monitoring system. We are also developing a clinical workstation with which physicians can review and examine the data from patients through various kinds of computer networks far diagnosis and report generation. Portable bedside units with LCD display and wired or wireless data communication capability will be developed in the near future. New parameter modules including cardiac output, capnograph, and other gas analysis functions will be added.

• Journal of Korea Technology Innovation Society
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• v.20 no.4
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• pp.1122-1158
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• 2017

Government-funded research institutes in the field of science and technology of Korea have contributed to the growth of the national economy and industrial development since the 1960s. However, those institutes recently have faced with criticism over the R&D performance on investment. Accordingly, we suggest two analytical approaches that estimate the economic benefit of the R&D performance of those institutes, (1) 'bottom-up' approach that aggregates the economic benefits of individual performances, e.g., technology transfer, technology support for small and medium enterprises, and the supply of researcher manpower and (2) 'top-down' one that estimates the contribution of those institutes on the economic growth of the industries that the R&D performance of those institutes is mainly utilized. In addition, by applying two approaches, we computed the economic benefit of the performance of the K institute in the 1996-2014 periods at 12.3 trillion won and 29.5 trillion won, respectively. Lastly, we suggest the feasibility of two approaches from the perspective of complementarity. Our study provides analytical approaches that estimate the economic benefit of the R&D performance from government funded research institutes in Korea. Lastly, our study contributes to the understanding of public on science and technology as well as the enhancement of legitimacy on those institutes among the public.

• Journal of the Society of Disaster Information
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• v.8 no.2
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• pp.158-170
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• 2012

Citizens'income has been increased along with the trend of rapid changes in society, and the quality of their lives has been improved as well. As much as the degree of increase of quality of life, the number of spectators for performing art events, etc. who desire to fulfill their needs for enjoyment of varied cultural performances have been increasing, and also a large number of spectators enjoys a variety of festivals being held in each provincial area as well as international events: we still remember such frantic rooting shown by citizens during 2002 World Cup drawing attention and interest of entire nation. There are always risks of loss of human lives if accidents occur as there sult of close-packed crowd gathered at the same time. Therefore, it is required to prepare adequate security measures in order to prevent various accidents before hand. It is hoped that this research work would be of help for further efficient and systematic security management for the performing arts centers or public theaters encouraging the event organizer and the private security firm and the Korea Private Security Association to exert great effort and investments in further projects for development of security technology. Also, it is required to build a performance culture to consider audience's safety first from the beginning to the end of the event on the basis of efficient security management. Furthermore, spect at or sare required to recognize the fact that safety in the site for performing arts should be guaranteed for everyone's sake, and, to achieve this, they are obliged to be more cooperative with the event organizer and the private security firm, forming a trinity all together, in order not to have safety threatening situations in the site of performing arts events.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.289-289
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• 2013

While there are plenty of studies on synthesizing semiconducting germanium nanowires (Ge NWs) by vapor-liquid-solid (VLS) process, it is difficult to inject dopants into them with uniform dopants distribution due to vapor-solid (VS) deposition. In particular, as precursors and dopants such as germane ($GeH_4$), phosphine ($PH_3$) or diborane ($B_2H_6$) incorporate through sidewall of nanowire, it is hard to obtain the structural and electrical uniformity of Ge NWs. Moreover, the drastic tapered structure of Ge NWs is observed when it is synthesized at high temperature over $400^{\circ}C$ because of excessive VS deposition. In 2006, Emanuel Tutuc et al. demonstrated Ge NW pn junction using p-type shell as depleted layer. However, it could not be prevented from undesirable VS deposition and it still kept the tapered structures of Ge NWs as a result. Herein, we adopt $C_2H_2$ gas in order to passivate Ge NWs with carbon sheath, which makes the entire Ge NWs uniform at even higher temperature over $450^{\circ}C$. We can also synthesize non-tapered and uniformly doped Ge NWs, restricting incorporation of excess germanium on the surface. The Ge NWs with carbon sheath are grown via VLS process on a $Si/SiO_2$ substrate coated 2 nm Au film. Thin Au film is thermally evaporated on a $Si/SiO_2$ substrate. The NW is grown flowing $GeH_4$, HCl, $C_2H_2$ and PH3 for n-type, $B_2H_6$ for p-type at a total pressure of 15 Torr and temperatures of $480{\sim}500^{\circ}C$. Scanning electron microscopy (SEM) reveals clear surface of the Ge NWs synthesized at $500^{\circ}C$. Raman spectroscopy peaked at about ~300 $cm^{-1}$ indicates it is comprised of single crystalline germanium in the core of Ge NWs and it is proved to be covered by thin amorphous carbon by two peaks of 1330 $cm^{-1}$ (D-band) and 1590 $cm^{-1}$ (G-band). Furthermore, the electrical performances of Ge NWs doped with boron and phosphorus are measured by field effect transistor (FET) and they shows typical curves of p-type and n-type FET. It is expected to have general potentials for development of logic devices and solar cells using p-type and n-type Ge NWs with carbon sheath.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.9
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• pp.543-551
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• 2016

Recently, the cultural industry has become an attractive industry which is having a dramatic effect with the rise of Hallyu offering many possibilities for development. Specially, the marketing techniques employed by the performing arts industry started to change to respond to consumer tastes and demands like other commodity markets, as the popular performing arts industry began to receive attention as a promising industry. It is important to identify the behavior of consumers in order to actively deal with the demands and tastes of consumers that are becoming increasingly diverse and individualized. The performing arts market needs to recognize the importance of its audience and to apply appropriate marketing techniques. This study attempted to empirically identify the value of performing arts perceived by the audience and to investigate the influence of the relationship between the perceived value, attitude formation and satisfaction with performing arts. In order to examine the influence of the value of performing arts on attitude and customer satisfaction, a reliability analysis and factor analysis were conducted to investigate the dependability and validity of the measured variables. In order to achieve the study's intended purpose, the structural equation model (SEM) was utilized as the core analysis method. As a result, it was found that the perceived value and attitude towards performing arts have a positive effect on customer satisfaction. The results of this study are expected to be used as the basic data for organizations that plan performances to improve their marketing and promotion around the audience and for more specific and detailed research in the future.

• Journal of Navigation and Port Research
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• v.32 no.6
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• pp.459-464
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• 2008

In this paper, we present the model-based fuzzy controller for container cranes which effectively performs set-point tracking control of trolley and anti-swaying control under system parameter and disturbance changes. The first part of this paper focuses on the development of Takagi-Sugeno (T-S) fuzzy modeling in a nonlinear container crane system. Parameters of the membership functions are adjusted by a RCGA to have same dynamic characteristics with nonlinear model of a container crane. In the second part, we present a design methodology of the model-based fuzzy controller. Sub-controllers are designed using LQ control theory for each subsystem in fuzzy model and then the proposed controller is performed with the combination of these sub-controllers by fuzzy IF-THEN rules. In the results of simulation, the fuzzy model showed almost similar dynamic characteristics compared to the outputs of the nonlinear container crane model. Also, the model-based fuzzy controller showed not only the fast settling time for the change in parameter and disturbance, but also stable and robust control performances without any steady-state error.