• Korean Journal of Computational Design and Engineering
• /
• v.11 no.1
• /
• pp.1-10
• /
• 2006

This paper addresses B-spline curve approximation of a set of ordered points to a specified toterance. The important issue in this problem is to reduce the number of control points while keeping the desired accuracy in the resulting B-spline curve. In this paper we propose a new method for error-bounded B-spline curve approximation based on adaptive selection of dominant points. The method first selects from the given points initial dominant points that govern the overall shape of the point set. It then computes a knot vector using the dominant points and performs B-spline curve fitting to all the given points. If the fitted B-spline curve cannot approximate the points within the tolerance, the method selects more points as dominant points and repeats the curve fitting process. The knots are determined in each step by averaging the parameters of the dominant points. The resulting curve is a piecewise B-spline curve of order (degree+1) p with $C^{(p-2)}$ continuity at each knot. The shape index of a point set is introduced to facilitate the dominant point selection during the iterative curve fitting process. Compared with previous methods for error-bounded B-spline curve approximation, the proposed method requires much less control points to approximate the given point set with the desired shape fidelity. Some experimental results demonstrate its usefulness and quality.

• Journal of the Society of Naval Architects of Korea
• /
• v.47 no.4
• /
• pp.525-532
• /
• 2010

In this paper, wave breakers which occur in two dimensional coasts are simulated using a SPH(Smoothed Particle Hydrodynamics) method which represents the movement of fluidic physical volume with particles. As continuative fluid is approximated to the particles, the simulations are performed using fully Lagrangian method without any grid system. Two-dimensional Navier-Stokes equations and continuity equation are used for the numerical simulations. To generate incident waves, a piston type wavemaker is employed. The accuracy of the wave which is numerically generated by the wavemaker is verified by comparing with analytical results. The computations are carried out with various wave heights and slopes. The wave patterns generated through the numerical simulations are compared with several existing experimental and computational results. Agreement between the experimental data and the computation results is comparatively good. Also, the breaker depth index and the breaker height index from the present calculations are compared with the existing experimental results, and the tendency is very similar.

• Journal of the Korean Home Economics Association
• /
• v.48 no.6
• /
• pp.1-8
• /
• 2010

The purpose of this study is to classify body type by BMI and to inquire about body satisfaction and fitness apparel depending on body type among women 20-50years of age. As a result, body types are classified into three groups: lean, normal, and obese figures. On front silhouette, the normal type occupies most in women belonged to lean figure group, the obese lower part of the bodytype in normal figure group, and the obese upper part of the body type in obese figure group. On the other, in side silhouette, the slender type is prevalent in lean figure group, hip obesity in normal figure group, and trunk obesity in obese figure group. In particular, women in the obese figure group were distributed among the various body types. The obese figure group had a lower fitness apparel in the measurement of circumference(e.g., chest, waist, and hip) related to obesity in comparison with measurement of length. Therefore, the development of an optimal sizing system in response to the various body types in the obese figure group is needed to provide more diversity in aesthetic design and continuity among various sizing systems.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.21 no.5
• /
• pp.850-858
• /
• 1997

A new a posteriori error estimator is introduced and applied to variational inequalities occurring in problems of flow through porous media. In order to construct element-wise a posteriori error estimates the global error is localized by a special mixed formulation in which continuity conditions at interfaces are treated as constraints. This approach leads to error indicators which provide rigorous upper bounds of the element errors. A discussion of a compatibility condition for the well-posedness of the local error analysis problem is given. Two numerical examples are solved to check the compatibility of the local problems and convergence of the effectivity index both in a local and a global sense with respect to local refinements.

• Proceedings of the KIEE Conference
• /
• 1999.11b
• /
• pp.267-269
• /
• 1999

One of the main jobs of the operators is to make it sure to have a service continuity in a fault situation. This paper proposes a restoration index which indicates the restoration capability of the feeder in case of a fault. A necessary and sufficient condition for a feeder to have 100% restoration of the outage is also described.

• Journal of Ocean Engineering and Technology
• /
• v.30 no.4
• /
• pp.320-326
• /
• 2016

Rip current forecasts, based on intensity, are marked in four levels—notice, watch, warning, and danger. However, numerical results are represented by current vectors, whose magnitudes are then converted into predictive levels. In the present study, the rose diagram is adapted as a determinative forecasting index and examined for the case of an ideal rip channel consisting of surface, bottom, and averaged currents. Further, it is employed in the sensitivity analysis of wave-induced currents generated by wave conditions at the Haeundae Beach. The simulation of surface onshore and bottom undertow currents is accomplished by including a mass flux term in the wave-averaged continuity equation.

• The Korean Journal of Nuclear Medicine Technology
• /
• v.27 no.1
• /
• pp.55-61
• /
• 2023

Purpose In this study, the monthly population distribution was calculated for statistical verification of 10 tests (CA19-9, CA15-3, testosterone, PTH, calcitonin, AFP, CEA, CA72-4, PSA, estradiol) with changed reagents, and the trend of change By comparing and analyzing the results, we want to verify the accuracy of the results and improve the reliability of the test. Materials and Methods From June 2021 to February 2023, for the 10 items in which the reagent was changed, the monthly percentage and standard deviation index before and after the reagent change were compared, respectively. At this time, the reference value was arbitrarily set for the comparison group in consideration of the reference value of the test item, and the groups were subdivided and compared, and the standard deviation index allowed range was -2.0 or more and 2.0 or less. Results For CA19-9, CA15-3, AFP, CEA, and calcitonin 5 test items, the change in monthly ratio in all test sections before and after the reagent change was kept constant. On the other hand, for CA72-4, PSA, testosterone, PTH, and estradiol items, the standard deviation index exceeded the acceptable standard after changing the reagent. CA72-4 test items showed an increasing trend in standard deviation index in the test section exceeding the reference value. In the case of the PSA test item, the maintenance ratio of 0.04 ng/mL was significantly decreased after changing the reagent. The testosterone test item had a standard deviation index of -2.5 in the test section exceeding 10.1 ng/mL after changing the reagent, and the standard deviation index of the PTH test item was out of the acceptable range in all test sections. It was confirmed that the estradiol test item showed an overall increase in the result value. Conclusion Through this study, the continuity and accuracy of the test results could be verified. It is considered that the stability of the test can be secured by analyzing the factors affecting the test result and solving the cause for the test item whose standard deviation index is out of the acceptable standard.

• KIPS Transactions on Software and Data Engineering
• /
• v.5 no.2
• /
• pp.95-106
• /
• 2016

Biometric data may appear different depending on the person and sasang Medicine has a close relationship with the Department. Biometric data not only mean a human heart rate, a blood pressure, a heart rate, and the past medical history, degree of aging, body mass index, but also is used as a reference measure for determining the state of health of the person. So biometric data should be reproduced for the application purposes, depending on their applications. In previous studies, because the biometric data is changed in real time and applies only to snap shut at the time of the continuity of the current time is excluded. Therefore, in this study in order to solve this problem, we propose a biometric data patton analysis model comprising a continuity of time in the big data environment consisting of biometric data. The proposed model can help determine the choice of needle position carefully when using the electronic acupuncture for care and health promotion.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.15 no.8
• /
• pp.2900-2922
• /
• 2021

In this paper, the power spectral density(PSD) for Multilevel Minimum Shift Keyed signal with modulation index h = 1/2 (M-ary MSK) are derived using the mathematical method of the Markov Chain model. At first, according to an essential requirement of the phase continuity characteristics of MSK signals, a complete model of the whole process of signal generation is built. Then, the derivations for autocorrelation functions are carried out precisely. After that, we verified the correctness and accuracy of the theoretical derivation by comparing the derived results with numerical simulations using MATLAB. We also divided the spectrum into four components according to the derivation. By analyzing these figures in the graphic, each component determines the characteristics of the spectrum. It is vital for enhanced spectral characteristics. To more visually represent the energy concentration of the main flap and the roll-down speed of the side flap, the specific out-of-band power of M-ary MSK is given. OMLCD(Optimum Maximum Likelihood Coherent Detection) of M-ary MSK is adopted to compare the signal received with prepared in advance in a code element T to go for the best. And M-ary MSK BER(Bit Error Rate) is compared with the same ary PSK (Phase Shift Keying) with M=2,4,6,8. The results show the detection method could improve performance by increasing the length of L(memory inherent) in the phase continuity.

• Journal of the Society of Disaster Information
• /
• v.15 no.2
• /
• pp.282-291
• /
• 2019

Purpose: In recent, mobile technology, as an axis of the fourth industry paradigm, is evolving into our daily life, economic activities and disaster safety management. However, since the location information service is insufficient, it is difficult to response the emergency situation adequately in the golden time. The purpose of this study is to propose a method to fine precisely the location of people who are in need of an emergency in the event of accidents and disasters. Method: This study investigates and compares existing literature and safety apps for national index number NFC application development. In addition, the system structure and the design method through the element technology through analysis of necessary function of the demander were carried out. Results: The results of this study were developed as a design and system that can be implemented in both direction and function to inform the location for emergency situation or disaster reporting in mobile. Conclution: It is possible to provide the disaster safety location service which can be utilized by the citizens in case of crisis by unifying the address system and integrating the location information using NFC.