• Journal of Wetlands Research
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• v.4 no.2
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• pp.1-11
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• 2002

The morphology, seed germination, and life history of Salix nipponica were investigated in the wetland of the Nam-River, Jinju, Gyeongsangnam-do, Korea from 2000 to 2001 to provide the basic data necessary for riverine ecosystem restoration through understanding the growth characteristics of Salix nipponica. Salix nipponica had stomata on only lower side and stomata type was paracytic. Salix nipponica produced many small and light seeds. The seed number per mature ament was 1599.4, seed mass of 0.04 mg, and fertilization rate of 66.1%. Seed germination was little affected by light. Germination rate was high and mean germination time was short Under flooding condition, seeds were germinated normally and were viable after as much as 14 days of flooding. But there were no differences under various water depths on germination rates. Tree age was closely correlated with more stem diameter than tree height and there was no difference of growth rate between male and female tree. Growth rate was most rapid for 2 to 3 years after germination, and length growth was almost stopped for more than 11 years even though mass growth was done. Besides even a second-year indivisual was flowered.

• Journal of Magnetics
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• v.19 no.4
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• pp.315-322
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• 2014

In this work, Artificial Neural Network (ANN) was used to model the dynamic behavior of ferromagnetic hysteresis derived from performing the mean-field analysis on the Ising model. The effect of field parameters and system structure (via coordination number) on dynamic critical points was elucidated. The Ising magnetization equation was drawn from mean-field picture where the steady hysteresis loops were extracted, and series of the dynamic critical points for constructing dynamic phase-diagram were depicted. From the dynamic critical points, the field parameters and the coordination number were treated as inputs whereas the dynamic critical temperature was considered as the output of the ANN. The input-output datasets were divided into training, validating and testing datasets. The number of neurons in hidden layer was varied in structuring ANN network with highest accuracy. The network was then used to predict dynamic critical points of the untrained input. The predicted and the targeted outputs were found to match well over an extensive range even for systems with different structures and field parameters. This therefore confirms the ANN capabilities and indicates the ANN ability in modeling the ferromagnetic dynamic hysteresis behavior for establishing the dynamic-phase-diagram.

• The Journal of Korean Medicine
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• v.31 no.4
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• pp.164-170
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• 2010

Objective: This study aimed to produce an overview of RCT for treatments of diabetic peripheral neuropathy. Method: All RCT studies for treatments of diabetic peripheral neuropathy were selected via PubMed. The general trend of RCT number, subject and result, including Oriental medicine, were analyzed. Result: A total 147 RCT studies were found. The number of RCT has rapidly increased since 2003. 114 RCTs were conducted with western drugs, while RCTs with electrical stimulation and Oriental medicine were eight and ten respectively. All RCTs with acupuncture, moxibustion and herbal drugs showed positive results. Conclusion: Oriental medicine-derived RCTs for diabetic peripheral neuropathy are very rare, even their potential was sufficient. This study may provide valuable information for development of Oriental medicine against diabetic peripheral neuropathy in the future.

• Journal of IKEEE
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• v.11 no.4
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• pp.297-306
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• 2007

A sensor network is composed of a large number of sensor nodes that are densely deployed in a field. Each sensor performs a sensing task for detection specific events. After detecting this event, location information of the sensor node is very important. Range-based scheme of the proposed approaches typically achieve high accuracy on either node-to-node distances or angles, but this scheme have a drawback because all sensor nodes have the special hardware. On the other hand, range-free scheme provides economic advantage because of no needed hardware even if that leads to coarse positioning accuracy. In this paper, we propose a range-free localization algorithm without range information in wireless sensor networks. This is a range-free approach and uses a small number of anchor nodes and known sensor nodes. This paper develops a localization mechanism using the geometry conjecture (perpendicular bisector of a chord). The conjecture states that a perpendicular bisector of a chord passes through the center of the circle.

• Journal of Magnetics
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• v.3 no.4
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• pp.120-122
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• 1998

The higher order harmonic components of magnetostriction during ac magnetization in 3% SiFe are measured as a function of the magnetizing angle respect to [001] axis using a constructed laser interferometry. The magnetostriction with magnetizing angle from [001] axis agrees ith the calculation based on domain reorientation. The relative amplitudes of odd and even harmonics respectively for magnetic induction and magnetostriction decrease with the order of harmonics, accompanying the contraction of the amplitudes. The contraction of harmonics order of magnetostriction harmonics is shown to be the even number times of that of magnetic induction.

• Bulletin of the Korean Mathematical Society
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• v.53 no.4
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• pp.1197-1211
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• 2016

Let R be a finite commutative ring with nonzero identity. We define ${\Gamma}(R)$ to be the graph with vertex set R in which two distinct vertices x and y are adjacent if and only if there exists a unit element u of R such that x + uy is a unit of R. This graph provides a refinement of the unit and unitary Cayley graphs. In this paper, basic properties of ${\Gamma}(R)$ are obtained and the vertex connectivity and the edge connectivity of ${\Gamma}(R)$ are given. Finally, by a constructive way, we determine when the graph ${\Gamma}(R)$ is Hamiltonian. As a consequence, we show that ${\Gamma}(R)$ has a perfect matching if and only if ${\mid}R{\mid}$ is an even number.

• The Journal of the Acoustical Society of Korea
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• v.15 no.4E
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• pp.9-13
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• 1996

We developed an iterative algorithm which could improve the resolution of reconstructed tomograms having random attenuation patterns and analyzed the limitation of this algorithm. The simple back-and forth propagation algorithm has depth resolution about four wavelengths. An iterative algorithm, based on back-and-forth propagation, can be used to improve the resolution of reconstructed tomograms. We analyzed the wavefield for multi-layered specimen and programmed iterative algorithm using Clanguage. Simulation results show that the images get clearer as the number of iterations increases. Also, unambiguous images can be reconstructed using this algorithm even when the layer separation is only two wavelengths. However, this iteration algorithm comes up with an incorrect solution for the number of projections less than five.

• Journal of Preventive Medicine and Public Health
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• v.31 no.4 s.63
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• pp.814-827
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• 1998

In this study we analyzed the insurance claims data to investigate the medical care utilization pattern of tuberculosis patients in private sector. We selected the claims of principal or secondary diagnosis with tuberculosis from claims database of National federation of Medical Insurance, from December 1995 to November 1996. Both spell-based analysis and person-based analysis were carried out. In spell-based analysis, type and location of treatment facilities, distribution of diagnoses, number of outpatient/inpatient treatments were analyzed. Additionally in person-based analysis, number of tuberculosis patients, demographic characteristics, number of treatments per person, frequency and pattern of change in source of care were analyzed. The results were as follows 1. The number of treatments with tuberculosis was 863,641 from 1 December 1995 to 30 November 1996. The number of patients was 313.964. 2. Most of tuberculosis patients in private sector were treated in general hospital (45.8%) and clinics(42.2%) 3. About 77.7% of tuberculosis patients who were treated more than two times did not change the source of care. 18,9% of tuberculosis patients changed source of care only once. Even when we limited tuberculosis patient to those who were treated more than five times and whose treatment period were longer than six months, 94.7% of patients did not change source of care at all, or changed treatment facility only once. 4. The probability of change in source of rare was higher in pulmonary tuberculosis, in twenties, and in rural area respectively than other tuberculosis. In conclusion, healer shopping of tuberculosis patients was not serious as expected. However special attention is needed to pulmonary tuberculosis in twenties and rural area.

• Geomechanics and Engineering
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• v.14 no.2
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• pp.115-129
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• 2018

This paper presents a set of results of plate load tests that imposed incremental cyclic loading to a sandy soil bed containing multiple layers of granulated rubber-soil mixture (RSM) at large model scale. Loading and unloading cycles were applied with amplitudes incrementally increasing from 140 to 700 kPa in five steps. A thickness of the RSM layer of approximately 0.4 times the footing diameter was found to deliver the minimum total and residual settlements, irrespective of the level of applied cyclic load. Both the total and residual settlements decrease with increase in the number of RSM layers, regardless of the level of applied cyclic load, but the rate of reduction in both settlements reduces with increase in the number of RSM layers. When the thickness of the RSM layer is smaller, or larger, settlements increase and, at large thicknesses may even exceed those of untreated soil. Layers of the RSM reduced the vertical stress transferred through the foundation depth by distributing the load over a wider area. With the inclusion of RSM layers, the coefficient of elastic uniform compression decreases by a factor of around 3-4. A softer response was obtained when more RSM layers were included beneath the footing damping capacity improves appreciably when the sand bed incorporates RSM layers. Numerical modeling using "FLAC-3D" confirms that multiple RSM layers will improve the performance of a foundation under heavy loading.

• Journal of Educational Research in Mathematics
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• v.21 no.3
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• pp.239-259
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• 2011

This study investigated the elementary school students' ability on the algebraic reasoning as generalized arithmetic. It analyzed the written responses from 648 second graders, 688 fourth graders, and 751 sixth graders using tests probing their understanding of the properties of whole number operations. The result of this study showed that many students did not recognize the properties of operations in the problem situations, and had difficulties in applying such properties to solve the problems. Even lower graders were quite successful in using the commutative law both in addition and subtraction. However they had difficulties in using the associative and the distributive law. These difficulties remained even for upper graders. As for the associative and the distributive law, students had more difficulties in solving the problems dealing with specific numbers than those of arbitrary numbers. Given these results, this paper includes issues and implications on how to foster early algebraic reasoning ability in the elementary school.