• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• 2012.06a
• /
• pp.59-61
• /
• 2012

TDOA 기법은 위치추정 기법의 하나로 간단한 구조와 높은 정확도를 가지는 장점으로 인해 실내측위, 군사, 의료 분야 등에 자주 사용된다. 본 논문에서는 MPM(Matrix Pencil Method)를 이용한 고분해능 TDOA 추정 기법을 제안한다. 제안된 기법은 기존의 교차상관을 이용한 TDOA 기법에 비교하여 높은 정확도를 가지며 CW(Continuous Wave)와 같은 협대역 신호에 적용이 가능하다. 또한 잘 알려진 고분해능 기법 중 하나인 MUSIC(Multiple Signal Classification)에서 공분산 행렬을 사용하는 것과 달리 수집된 데이터를 바로 행렬로 만들어 사용하므로 복잡성이 낮은 특징이 있다. 제안된 기법의 성능을 검증하기 위해 소프트웨어 시뮬레이션 통해 SNR에 따른 오차와 연산량 측면에서 MUSIC 기법과 비교하였다.

• Journal of Electrochemical Science and Technology
• /
• v.11 no.3
• /
• pp.248-256
• /
• 2020

In this study, pyrocatechol violet (Pcv) is proposed for the first time as an efficient electrocatalyst for oxidation of sulfide and flow injection analysis (FIA) of sulfide. A graphite pencil electrode (GPE) was modified with Pcv via immersion of the GPE into 0.01 M Pcv solution for 15 min. Cyclic voltammograms (CVs) demonstrated that Pcv/GPE exhibits a good electrocatalytic performance due to shift in the potential from +400 at bare GPE to +70 mV at Pcv/GPE and obtaining an enhancement in the peak current compared with the bare GPE. A linear range between 0.25 and 250 μM sulfide with a detection limit of 0.07 μM was obtained from the recorded current-time curves in Flow Injection Analysis (FIA) of sulfide. Sulfide in water samples was also successfully determined using the proposed FI amperometric methods.

• Journal of the Korean Data and Information Science Society
• /
• v.18 no.4
• /
• pp.1073-1079
• /
• 2007

The purpose of this study is to present the relationship between the computer learning and the paper and pencil learning through the math learning (simple computation and complex computation) and the cartoon learning and text learning. The canonical correlation and pairwise t-test of the SMR asymmetry brainwaves of the left and the right brain show the brainwaves with the respect to the manner in which they process information during the specified task by identifying the relative activity of the brainwaves of the left and the right brain. SMR brainwave which known as the scientific measure tool for the activity and the function of the neuronal cell were found to predict the level of the awakening to check the readiness of study preparation. Computer education as a medium of the individualized and the repetitive education shows the difference from the paper and the pencil test in the respect of the differences and the relationship of the SMR brainwave of the learning process.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 1997.04a
• /
• pp.782-787
• /
• 1997

This paper proposes methods for pencil machining and uncut area machining. Based on Z-map represented by triangular facets, self-intersection-free offset surface is generated with K-offset method in case of ball mill and flat mill Pencil machining can elliminate overload area before main machining rough, semi-finish and finish cutting,preventing fluctuations of cutting forces in concave regions form causing bad machining condition. Low productivity is caused by uncut area which has excessive or irreguar finishing allowance. Uncut area machining has the finishing allowance keep uniformly on part surface. This paper deals with two types of uncaut area, machining detection of excessive area and user-defined area.

• Journal of Korean Foot and Ankle Society
• /
• v.21 no.1
• /
• pp.33-38
• /
• 2017

Purpose: The patient-reported outcome measure (PROM) is used to quantify the subjective state of patients before and after the treatment. The electronic method was recently developed and used for the completion of PROM, in addition to the conventional paper and pencil method. This study identified whether the results of Foot Function Index (FFI) and Foot and Ankle Outcome Score (FAOS) using the paper and pencil method was different from those using the electronic method. Materials and Methods: Between May 2016 and August 2016, 42 patients who were admitted to the Seoul Foot and Ankle Center two days before surgery were included for evaluation. The mean age was 46 years (range, 21~72 years). There were 29 males and 13 females. To use the electronic method, the PADAS software (PADAS, Seoul, Korea) was implemented using a touch pad. The primary trial of FFI and FAOS was performed using either the paper-and-pencil method or the electronic method. At 24 hours after the primary test, a secondary trial of FFI and FAOS was performed using the other method. Then, we identified the reliability of FFI and FAOS between the two methods by calculating the intraclass coefficient. Results: Twenty-two patients underwent the first trial using the paper-and-pencil method, and 20 patients underwent the first trial using the electronic method. Of the 42 patients, 8 patients were excluded from this study and only 34 patients were included in this study. The reliability of FFI was excellent with an intraclass coefficient of 0.957, and the reliability of FAOS was also excellent with an intraclass coefficient of 0.840. Conclusion: The paper-and-pencil method and the electronic method have the same result for the completion of FFI and FAOS in this study. Therefore, it is commonly considered that the completion of FFI and FAOS using the electronic method can be applied in practice.

• Journal of the Korean Mathematical Society
• /
• v.36 no.3
• /
• pp.567-580
• /
• 1999

We prove two variants of a base-point-free pencil trick, which are similar in the spirit of the proof, and apply them to the study of special divisors on a smooth plane curve involving a theorem of Max Noether.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.66 no.8
• /
• pp.1242-1249
• /
• 2017

In this paper, we propose a new algorithm for the performance analysis of the sidelobe blanker (SLB) in radar system, which is based on the matrix pencil method (MPM). In general, the SLB in radar is composed of the main antenna, the auxiliary antenna, and the processing unit. The auxiliary antenna with wide beamwidth receives interference signals such as jamming or clutter signals. The main antenna with high gain receives the target signal in the main beam and the interference signals in the sidelobe. In this paper the Swerling model is used as the target echo signal by considering a probabilistic radar cross section (RCS) of the target. To estimate the SLB performance it needs to calculate the probability of target detection and the probability of blanking the interference by using the signals received from the main and auxiliary antennas. The detection probability and the blanking probability include multiple summations of infinite series with infinite integrations, of which convergence rate is very slow. Increase of summation range to improve the calculation accuracy may lead to an overflow error in computer simulations. In this paper, to resolve the above problems, we used the MPM to calculate a summation of infinite series and improved the calculation accuracy and the convergence rate.

• Proceedings of the Korean Society of Medical Physics Conference
• /
• 2002.09a
• /
• pp.291-293
• /
• 2002

Accurate dose calculation in radiation treatment planning is most important for successful treatment. Since human body is composed of various materials and not an ideal shape, it is not easy to calculate the accurate effective dose in the patients. Many methods have been proposed to solve the inhomogeneity and surface contour problems. Monte Carlo simulations are regarded as the most accurate method, but it is not appropriate for routine planning because it takes so much time. Pencil beam kernel based convolution/superposition methods were also proposed to correct those effects. Nowadays, many commercial treatment planning systems, including Pinnacle and Helax-TMS, have adopted this algorithm as a dose calculation engine. The purpose of this study is to verify the accuracy of the dose calculated from pencil beam kernel based treatment planning system Helax-TMS comparing to Monte Carlo simulations and measurements especially in inhomogeneous region. Home-made inhomogeneous phantom, Helax-TMS ver. 6.0 and Monte Carlo code BEAMnrc and DOSXYZnrc were used in this study. Dose calculation results from TPS and Monte Carlo simulation were verified by measurements. In homogeneous media, the accuracy was acceptable but in inhomogeneous media, the errors were more significant.

• Journal of the Korean Chemical Society
• /
• v.50 no.3
• /
• pp.208-215
• /
• 2006

A simply prepared graphite, pencil-type working electrode was utilized to monitor fenitrothion concentrations, using the cyclic voltammetry (CV) and square-wave (SW) stripping voltammetry methods. The optimum conditions for analysis were sought. A very low detection limit was obtained compared to that obtained when other common voltammetry methods are used. The optimal parameters of the pencil-type electrode were found to be as follows: a pH of 3.7, a frequency of 500 Hz, an SW amplitude of 0.1 V, an increment potential of 0.005 V, an initial potential of -0.9V, and a deposition time of 500 sec. The analytical detection limit was determined to be 6.0 ngL-1 (2.16410-11 molL-1) fenitrothion at SW anodic and CV, and the relative standard deviation at the fenitrothion concentration of SW anodic 10 ugL-1 was 0.30% (n = 15) under the optimum conditions. Analysis was directly conducted through in-vivo real-time assay.

• Journal of Elementary Mathematics Education in Korea
• /
• v.6 no.1
• /
• pp.59-76
• /
• 2002

This study, through the cases occurred in mathematics pencil-paper test, after analyzing the types and the factors of misunderstanding, was to seek to pursue the alternatives to diminish the misunderstanding caused in paper test. When classifying misunderstanding shown in pencil-paper test, four types are found - unsuitable edit, unsuitable organization, formal/typical habits, and unsuitable question situation. One Way, considering accomplishment rate based on existence and nonexistence of misunderstanding factors, the testing paper, that is, type A with misunderstanding factors, showed that the accomplishment rate is 10 percent below the testing paper, type B excluding misunderstanding factors. Also, after distinguishing only items including misunderstanding factors, in comparison with the accomplishment rate, the results showed about 22% difference. And in the type of misunderstanding factor, when system was unsuitable, the degree of misunderstanding appeared seriously. The more complicated many types were, the higher the number of misunderstanding cases appeared. Based on these study results, the conclusions are the followings : First, teachers should try to develop examination papers for exact evaluation. Second, teachers, while students are solving the questions, misunderstanding recognize what are the misunderstanding factors they feel. Third, in the pencil-paper evaluation, the work that teachers should consider importantly, is to analyze students' thought process. Fourth, teachers should try for smooth communications with students.