• The KSFM Journal of Fluid Machinery
• /
• v.8 no.4 s.31
• /
• pp.27-38
• /
• 2005

The present study investigated the effect of relative position of the blade on blade surface heat transfer. The experiments were conducted in a low speed wind tunnel with a stationary annular turbine cascade. The test section has a single turbine stage composed of sixteen guide vanes and blades. The chord length of the blade is 150 mm and the mean tip clearance of the blade is $2.5\%$ of the blade chord. The Reynolds number based on blade inlet velocity and chord length is $1.5{\times}105$ and mean turbulence intensity is about $3\%$. To investigate the effect of relative position of blade, the blade at six different positions in a pitch was examined. For the detailed mass transfer measurements, a naphthalene sublimation technique was used. In general, complex heat transfer characteristics are observed on the blade surface due to various flow characteristics, such as a laminar flow separation, relaminarization, flow acceleration, transition to turbulence and tip leakage vortices. The results show that the blade relative position affects those heat transfer characteristics because the distributions of incoming flow velocity and turbulence intensity are changed. Especially, the heat transfer pattern on the near-tip region is significantly affected by the relative position of the blade because the effect of tip leakage vortex is strongly dependent on the blade position. On the pressure side, the effect of blade position is not so significant as on the suction side surface although the position and the size of the separation bubble are changed.

• Journal of the Korean Institute of Intelligent Systems
• /
• v.21 no.4
• /
• pp.481-486
• /
• 2011

Recently, most presentations have been presented on the screen using the computer. This paper suggests that the computer can be controlled by the gesturing recognition, without the help of any person or tools. If we use only information in the form of images, we should have a high-resolution camera for capturing the images and a computer that can treat high-resolution images. However, this paper will present a solution whereby a low-resolution camera can be used at the stage. It uses the supersonic sensor to trace the presenter's location and a low-resolution camera for capturing the necessary limited and small area. The gesture is defined by the number of fingers and one's hand positions which are recognized by the Erosion / Dilation and Subtraction algorithm. The system this paper addresses has improved 13%, when comparing tests between the image-only data system and this paper's system. The gesture recognition tests have a 98% success rate.

• Journal of the Korean Institute of Intelligent Systems
• /
• v.19 no.4
• /
• pp.478-484
• /
• 2009

Automatic speech recognition(ASR) is attractive technique in trend these day that seek convenient life. Although many approaches have been proposed for ASR but the performance is still not good in noisy environment. Now-a-days in the state of art in speech recognition, ASR uses not only the audio information but also the visual information. In this paper, We present a novel lip detection method for visual speech recognition in mobile environment. In order to apply visual information to speech recognition, we need to extract exact lip regions. Because eye-detection is more easy than lip-detection, we firstly detect positions of left and right eyes, then locate lip region roughly. After that we apply K-means clustering technique to devide that region into groups, than two lip corners and lip center are detected by choosing biggest one among clustered groups. Finally, we have shown the effectiveness of the proposed method through the experiments based on samsung AVSR database.

• Journal of Powder Materials
• /
• v.24 no.6
• /
• pp.477-482
• /
• 2017

Nitrogen-doped titanium dioxide (N-doped $TiO_2$) is attracting continuously increasing attention as a material for environmental photocatalysis. The N-atoms can occupy both interstitial and substitutional positions in the solid, with some evidence of a preference for interstitial sites. In this study, N-doped $TiO_2$ is prepared by the sol-gel method using $NH_4OH$ and $NH_4Cl$ as N ion doping agents, and the physical and photocatalytic properties with changes in the synthesis temperature and amount of agent are analyzed. The photocatalytic activities of the N-doped $TiO_2$ samples are evaluated based on the decomposition of methylene blue (MB) under visible-light irradiation. The addition of 5 wt% $NH_4Cl$ produces the best physical properties. As per the UV-vis analysis results, the N-doped $TiO_2$ exhibits a higher visible-light activity than the undoped $TiO_2$. The wavelength of the N-doped $TiO_2$ shifts to the visible-light region up to 412 nm. In addition, this sample shows MB removal of approximately 81%, with the whiteness increasing to +97 when the synthesis temperature is $600^{\circ}C$. The coloration and phase structure of the N-doped $TiO_2$ are characterized in detail using UV-vis, CIE Lab color parameter measurements, and powder X-ray diffraction (XRD).

• Journal of Conservation Science
• /
• v.12 no.1 s.15
• /
• pp.1-14
• /
• 2003

Chemical characteristics of whitewares excavated from the of official kiln of the Choseon Dynasty period in Gwangju, Gyeonggido have been stuied using x-ray diffraction, inductively coupled plasma atomic absorption spectrometry and energy dispersive spectrometry. This study shows that most of whitewares excavated from the kiln site are similar in chemistry to each other regardless of their excavated positions and that the their bodies were not made of feldspar minerals. However, the whiteware from sedimentation 1 of waste articles shows mineralogical characters different from those of other sites. This result is in accordance with the report that the whitewares from sedimentation 1 of waste articles have characters different from other sites. The whiteware glaze was produced from raw minerals of both lime and alkali-lime system resulting in wide variation in chemical composition.

• The Korean Journal of Community Living Science
• /
• v.20 no.3
• /
• pp.437-448
• /
• 2009

The purpose of this study was to examine the effect of individual and interpersonal variables on early childhood teachers' efficacy of problem behavior guidance. Individual variables consisted of teachers' socio-demographic characteristics, experience of training course on problem behavior guidance and warm-hearted attitude. Interpersonal variables consisted of intimacy with colleagues, support from the principal of a kindergarten, parental partnerships. Subjects were 122 early childhood teachers in Busan. Major findings were as follows. There were significant differences in teachers' efficacy of problem behavior guidance with respect to teachers' age, teaching experience, position, marriage status, experience of training course on problem behavior guidance, warm-hearted attitude, intimacy with colleagues, and support from the principal of a kindergarten. In other words, a higher level of teachers' efficacy of problem behavior guidance was shown in the teachers who were older, highly experienced, or in higher positions. In addition, teachers who were married, had completed a training course on problem behavior guidance, had a higher warm-hearted attitude, had a intimacy with colleagues, or had a support from the principal of a kindergarten were found to have higher efficacy of problem behavior guidance. As results of examining relative effects of individual and interpersonal variables on efficacy of problem behavior guidance, the influential variables are teaching experience, warm-hearted attitude, support from the principal of a kindergarten, and position in that order.

• The Journal of Churna Manual Medicine for Spine and Nerves
• /
• v.8 no.1
• /
• pp.15-26
• /
• 2013

Objectives: The purpose of this study is to find out the relationship between lumbar lordotic angle and low back pain patterns. Methods: We randomly selected the 1191 patients (595 males, 596 females) who have visited Bu-Chun Jaseng Hospital of Korean Medicine with low back pain. We have taken lumbar x-ray films and measured their lumbar lordotic angle, the angle formed between L1 superior margin and S1 superior margin. We investigated 1191 patients' low back pain patterns(date of occurence, existence of radiating pain, trend of increasing pain with lumbar extention and flexion, trend of increasing pain with standing and sitting positions) and analysed the relationship between lumbar lordotic angle and low back pain patterns. Results: 1. The lumbar lordotic angle of the acute phase patient is more straight than the chronic one. 2. The lumbar lordotic angle of the patients with radiating pain is more straight than the patients without radiating pain. 3. At acute phase, the lumbar lordotic angle of the patients with increasing pain from lumbar extention is more straight than those with increasing pain from lumbar flexion. 4. At chronic phase, the lumbar lordotic angle of the patients with increasing pain from lumbar flexion is more straight than those with increasing pain from lumbar extention. Conclusions: There was a significant correlation between lumbar lordotic angle and low back pain.

• Journal of Korean Society of Coastal and Ocean Engineers
• /
• v.19 no.5
• /
• pp.457-466
• /
• 2007

The effect of depth correction in the coastal sea has been investigated through a series of tide simulations in the area of $115{\sim}150^{\circ}E,\;20{\sim}52^{\circ}N$ of northwestern Pacific with $1/12^{\circ}$ resolution. Comparison of the solutions varying the minimum depth from 10m to 35 m with the 5m interval shows that the amplitude accuracies of $M_2,\;S_2,\;K_1$ tide using the minimum depth of 25 m have been improved up to 42%, 32%, 26%, respectively, comparing to those using the minimum depth of 10m. The discrepancy between model results using different minimum depth is found to be up to 20 cm for $M_2$ tidal amplitude around Cheju Islands and the positions of amphidromes are dramatically changed in the Bohai Sea. The calculated ARE(Averaged Relative Error) values have been minimized when the bottom frictional coefficient and the minimum depth is 0.0015 and 25 m, respectively.

• The Journal of the Korea Contents Association
• /
• v.6 no.1
• /
• pp.80-84
• /
• 2006

Motivated by the fact that cluster reduction strategies such as inserting a vowel or deleting a consonant in resolving English complex clusters differ depending on studies, this paper investigates the repair strategies employed by Korean EFL students. A total of 60 college students participated in the present study and the participants' production of English voiceless word-initial and word-final clusters was measured using the materials designed for this study. It has been shown that prosodic positions such as onset and coda and the number of cluster sequences influenced cluster reduction strategies. The error rates of both insertion and deletion were noticeably higher in the coda position than in the onset position and both insertion and deletion error rates were higher in triconsonatal cluster than in biconsonantal cluster sequences. Overall, the insertion rate was higher than the deletion rate. However, the deletion rate was significantly higher than the insertion rate in triconsonantal coda cluster sequences. Because of this, the deletion rate was higher than the insertion rate for triconsonantal cluster sequences across onset and coda. Also, the high deletion rate of triconsonantal coda clusters contributed to the high deletion rate for the coda clusters in general.

• The Journal of the Korea Contents Association
• /
• v.6 no.12
• /
• pp.128-135
• /
• 2006

RTLS(Real Time Location System) is the system to provide information and real-time location of tagged objects by using RTLS tag. In this paper, in order to enhance the performance of the port operation system, and efficient operation method of yard is suggested by applying RFID(Radio Frequency Identification)-based RTLS that provides real-time accurate positions of containers. In the group-based loading sequence system, the containers in the same group should have the similar characteristics such as POD(Port of Destination), size, weight, etc. In order to run this system, we propose the scheme using the parameters to the unspecified N bytes of RFID tag specified in ISO 18000-7. According to simulation result, the group-based system reduces the re-handling ratio of TC(Transfer Crane) in yard. It will reduce the whole lead-time in the process of port pogistics.