• International Journal of Highway Engineering
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• v.18 no.6
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• pp.161-171
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• 2016

OBJECTIVES : Many roadway departure crashes on the freeway interchange are due to the running speed being greater than the design speed. This study aims to ensure a safe and pleasant driving experience for the driver by increasing the superelevation based on the running speed on the highway interchange ramp. METHODS : The mean running speed for each type of ramp is calculated on site survey more than 10 interchanges. Using the mean running speed, we calculated the superelevation and the side friction using the method given in "A Policy on Geometric Design of Highways and Street" (Pages 145-166, 2001). Then, we applied the modified method to the superelevation range. Finally, we ensured safety using the Degree of Safety that is proven by the centrifugal acceleration ratio as suggested by Joseph Craus (1978). RESULTS : The mean running speeds are 50 km/h and 65 km/h when the design speeds are 40 km/h and 50 km/h, respectively. After the application of the new method used in this study, the superelevation will be increased by 9.0% and 10.0% when the mean running speeds are 50 km/h and 65 km/h, respectively. CONCLUSIONS : A higher superelevation can give the driver a more comfortable and safe driving environment. However, the driver needs to be aware of snow and low-temperature conditions.

• Transactions of the Korean Society of Mechanical Engineers
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• v.15 no.1
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• pp.69-77
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• 1991

A collision-free trajectory planning algorithm using an iterative learning concept is proposed for dual robot arms in a 3-D common workspace to accurately follow their specified paths with constant velocities. Specifically, a collision-free trajectory minimizing the trajectory error is obtained first by employing the linear programming technique. Then the total operating time is iteratively adjusted based on the maximum trajectory error of the previous iteration so that the collision-free trajectory has no deviation from the specified path and also that the operating time is near-minimal. To show the validity of the proposed algorithm, a numerical example is presented based on two planar robots.

• 한국생물공학회:학술대회논문집
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• 2003.04a
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• pp.393-397
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• 2003

P. aeruginosa F722 produces biosurfactant (BS) while degrading hydrocarbons. BS production was 0.78 $g/{\ell}$ on the C-medium. However, BS production increased by 1.66 $g/{\ell}$ on the condition of 0.05% (w/v) $NH_4Cl+0.1%$ (w/v) yeast extract and 3.0% (w/v) glucose, which was proved to be advantageous to BS production. In the condition of aeration of 1.0 liter per minute (LPM), BS production was increased 20% (1.94 $g/{\ell}$)more than 1.66 $g/{\ell}$ produced when the air was not supplied. Moreover, the velocity of glucose degradation at both of log and stationary growth phases increased from 0.25 and 0.18 $h^{-1}$ to 0.33 and 0.29 $h^{-1}$ respectively when the air was supplied. Besides, BS activity was more stabilized on the condition of air supply.

• Korean Journal of Food Science and Technology
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• v.24 no.3
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• pp.221-225
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• 1992

The possibility of using Chinese cabbage juice as a substrate for the production of Candida utilis cell mass was explored. Dry cell weight production and cell yield coefficient were 1.35-1.45 g/100 ml undiluted juice and 47-50%, respectively, when C. utilis was grown by shake flask culture at $30^{\circ}C$ for 24 hr on more than three-fold diluted Chinese cabbage juice to make the final sugar content be equal to or less than 1.0%. Supplementation of glucose(2%), $KH_2PO_4(0.2%)$ and $(NH_4)_2SO_4(0.2%)$ to three-fold diluted Chinese cabbage juice did not enhance the dry cell weight yield or the protein content of the yeast cell, while supplementation of yeast extract(0.2%) and peptone(0.2%) increased dry cell weight production and protein content but not as much as the amount of each nutrient added. It was found that Chinese cabbage juice was an excellent substrate for the cultivation of C. utilis.

• Journal of radiological science and technology
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• v.26 no.3
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• pp.19-24
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• 2003

We carried out studies on development and characteristic of ultrasound brast training biopsy phantom. the major finding were of follow ; (1) C type TMM was shown good homogeneity, brightness and attenuation as like human soft tissue. (2) $TiO_2$ 4.10%w/v TMM was shown good homogeneous echo texture and propagated speed as like the human Tissue. (3) $TiO_2$ type TMM was appeared lower brightness and higher penetration rate than C type TMM. Therefor, Breast TM phantom and target material TMM will be useful $TiO_2$ 4.10 %w/v TMM and C 2.09 %w/v TMM.

• Fire Science and Engineering
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• v.25 no.1
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• pp.63-71
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• 2011

When it comes to slim floor using asymmetric H-beam, it was designed that the steel member is embedded in concrete with relatively low thermal conductivity so as to minimize the deterioration of rigidity of steel member in fire. But given the bottom flange of asymmetric H-beam is directly exposed to the fire, the measure of applying the fireproof coating to improve the fire rate performance of slim floor beam was sought. The test was aimed at comparing the fireproof performance by adjusting the load ratio of 0.4 and 0.3, and The test was carried out to identify the 3-hour fire performance by reinforcing the beam as well as applying the fireproof coat, In the wake of comparing the specimen depending on variation of load ratio, lowering load ratio by 0.1 resulted in difference of 12 minutes and deflection was 39 mm. It was able to improve 12 minutes by reinforcing the beam and up to 102.4 mm in deflection.

• Journal of Korea Multimedia Society
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• v.14 no.2
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• pp.288-294
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• 2011

In this paper we define the probability models for determining the disparity map given stereo images and derive the methods for solving the problem, which is proven to be equivalent to an energy-based stereo matching. Under the assumptions the difference between the pixel on the left image and the corresponding pixel on the right image and the difference between the disparities of the neighboring pixels are exponentially distributed, a recursive approach for estimating the MRF regularizing parameter is proposed. The proposed method alternates between estimating the parameters with the intermediate disparity map and estimating the disparity map with the estimated parameters, after computing it with random initial parameters. Our algorithm is applied to the stereo matching algorithms based on the dynamic programming and belief propagation to verify its operation and measure its performance.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• autumn
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• pp.422-425
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• 2003

The purpose of this study is using a TACT planning and scheduling for apartment houses construction that have many of same units. Because using a TACT planning and scheduling is concluded time reduction at same units as apartment plan. The main contents of this study are 1) window and door work through the field study, 2) adjust worker assignment to minimize work time variation, and 3) an effect of working time through a case study. As a result, the total working time can be improved $21.2\%$ by using the TACT planning and scheduling. The stu요 recommends that 1) establish an accurate data between work period and resource, and 2) preparation to measures minimization of waiting time before using a TACT planning and scheduling.

• Journal of Korea Multimedia Society
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• v.4 no.3
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• pp.230-237
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• 2001

Adaptive filters are widely used for acoustic echo canceler, adaptive equalizer and adaptive noise canceler. Coefficients of adaptive filters are updated by NLMS algorithm. However, Coefficients are misaligned by ambient noises when they are adapted by NLMS algorithm. In this Paper, a method determined the adaptation constant by low-pass filtered instantaneous gradient vector of LMS algorithm using orthognality principles of optimal filter is proposed. At initial states, instantaneous gradient vector, that is the cross-correlation of input signals and estimation error signals, has large value because input signals are remained in estimation error signals. When an adaptive filter is conversed, the cross-correlation will be close to zero. It isn's affected by ambient noises because ambient noises are uncorrelated with input signals. Determining adaptation constant with the cross-correlation, adaptive filters can be robust to ambient noises and the convergence rate doesn't slower As results of computer simulations, it is shown that the performance of proposed algorithm is betted than that of conventional algorithms.

• Journal of Korea Multimedia Society
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• v.10 no.1
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• pp.26-35
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• 2007

We present a robust face tracking system from the sequence of video images based on effective detector and Kalman filter. To construct the effective face detector, we extract the face features using the five types of simple Haar-like features. Extracted features are reinterpreted using Principal Component Analysis (PCA), and interpreted principal components are used for Support Vector Machine (SVM) that classifies the faces and non-faces. We trace the moving face with Kalman filter, which uses the static information of the detected faces and the dynamic information of changes between previous and current frames. To make a real-time tracking system, we reduce processing time by adjusting the frequency of face detection. In this experiment, the proposed system showed an average tracking rate of 95.5% and processed at 15 frames per second. This means the system is robust enough to track faces in real-time.