• Journal of The Korean Astronomical Society
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• 제23권1호
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• pp.1-13
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• 1990

New uvby photoelectric photometry was carried out for a $\delta$ Scuti variable, HR1170. By applying the Fourier method and the linear least square method, three frequencies were derived: $f_1=10.06134c/d$ ($P_1=0.^d0994$). $f_2=11.91754c/d$ ($P_2=0.^d0839$). $f_3=18.96776c/d$ ($P_3=0.^d0527$). From the observed pulsational constants and from the phase difference and amplitude ratios for color(b-y) and magnitude y. three different pulsation modes (n, l) of $f_1(0,0)$, $f_2(1,2)$, $f_3(3,2)$ are deduced, indicating the existence of nonradial mode in HR1170. Some physical parameters indicate that HR1170 is evolving at the stage of H-shell burning.

• Journal of applied mathematics & informatics
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• 제40권3_4호
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• pp.409-431
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• 2022

In this paper, we deal with the existence of solutions of the following system of nonlinear rational difference equations with order five $x_{n+1}=\frac{y_{n-3}x_{n-4}}{y_n(a+by_{n-3}x_{n-4})}$, $y_{n+1}=\frac{x_{n-3}y_{n-4}}{x_n(c+dx_{n-3}y_{n-4})}$, n = 0, 1, ⋯, where parameters a, b, c and d are not executed at the same time and initial conditions x_-4, x_-3, x_-2, x_-1, x₀, y_-4, y_-3, y_-2, y_-1 and y₀ are non zero real numbers.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• 제3권2호
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• pp.39-45
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• 2010

In this paper, an equally spaced $3{\times}2$ microstrip patch array antenna based on the fundamental infinite wavelength supported by the composite right/left-handed (CRLH) transmission line (TL) is proposed. The proposed CRLH TL unit cell consists of an inter-digit capacitor to realize left-handed (LH) series capacitance and non-symmetric shunt meander line with a shorted via to realize LH shunt inductance. At the infinite wavelength frequency of 2.09 GHz a 6-port series power divider consisting of a 19 unit cells shows a maximum magnitude difference of 0.73 dB and a $0.52^{\circ}$ maximum phase difference between output ports. The measured resonant frequency and maximum gain of the fabricated array antenna is 2.09 GHz and 10.98 dBi, respectively.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• 제11권5호
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• pp.89-100
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• 2001

The Ritz method Is applied In a three-dimensional (3-D) analysis to obtain accurate frequencies for thick. linearly tapered. annular plates. The method is formulated for annular plates haying any combination of free or fixed boundaries at both Inner and outer edges. Admissible functions for the three displacement components are chosen as trigonometric functions in the circumferential co-ordinate. and a1gebraic polynomials in the radial and thickness co-ordinates. Upper bound convergence of the non-dimensional frequencies to the exact values within at least four significant figures is demonstrated. Comparisons of results for annular plates with linearly varying thickness are made with ones obtained by others using 2-D classical thin place theory. Extensive and accurate ( four significant figures ) frequencies are presented 7or completely free. thick, linearly tapered annular plates haying ratios of average place thickness to difference between outer radius (a) and inner radius (b) radios (h$_{m}$/L) of 0.1 and 0.2 for b/L=0.2 and 0.5. All 3-D modes are included in the analyses : e.g., flexural, thickness-shear. In-plane stretching, and torsional. Because frequency data liven is exact 7o a\ulcorner least four digits. It is benchmark data against which the results from other methods (e.g.. 2-D 7hick plate theory, finite element methods. finite difference methods) and may be compared. Throughout this work, Poisson\`s ratio $\upsilon$ is fixed at 0.3 for numerical calculations.s.

• Journal of Korean Society of Forest Science
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• 제83권4호
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• pp.521-530
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• 1994

Voume functions, which are usually expressed by the function of dbh and height, are estimated commonly through the regression analysis with the highest statistical accuracy considered. In Korea, general volume functions for each tree species were prepared by means of the regression analysis with the exponential function ($V=aD^bH^c$) having the dbh(D) and height(H) as independent variables. In this study, regional stem curve functions for the Pinus densiflora in Kangwon-province were derived and a regional volume function model, in which the stem volume can be directly estimated through the rotational integral of the regional stem curve functions, was prepared. The regional volume estimated by the prepared model was more accurate than the volume by the general volume table for the Pinus densiflora in Kangwon-province. Additionary, the form of stem curves derived by the regional stem curve functions showed difference from each other. The stem in Youngwol and Wonju taper down more fast in upper part than that in other regions. These various stem forms also led to the regional difference in volume estimates.

• Korean Journal of Optics and Photonics
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• 제12권4호
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• pp.312-319
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• 2001

We proposed a B-RWG LD (Buried-ridge waveguide laser diode) having more merits than a conventional RWG-LD. It's ridge width is controlled easily, it has the advantage of being more planar than the RWG-LD and it is possible to control refractive index with growth layer thickness. Before fabricating the device, we designed the optimal device for single mode, high efficiency and high power operation. From theoretical analysis, we have to control the $d_2, d_3$ layer thicknesses for lateral effective index difference, $\Delta_{nL}$ to be higher than critical value, and simultaneously consider the ridge width for single mode and low threshold current operation. As a result, it is possible to make a single mode LD having the ridge width of $6~9{\mu}m$ if the lateral effective index difference was controlled properly. perly.

• Journal of Acupuncture Research
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• 제36권4호
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• pp.230-237
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• 2019

Background: The purpose of this study was to investigate the clinical efficacy of Korean medicine combination treatments for recurring back pain after medical procedures. Methods: This was a retrospective study performed on 311 patients admitted to Daejoen Jaseng hospital who were diagnosed with lumbar spine herniated intervertebral discs. The patients were divided into 2 groups according to whether or not they had undergone at least one medical procedure on the lumbar spine. They were assessed with Numeric Rating Scale (NRS), Oswestry Disability Index (ODI) and EuroQol-5 Dimensions Index (EQ-5D) before and after treatment. Results: Patients who experienced a medical procedure on the lumbar spine in the prehospital phase (Group A), statistically significantly improved EQ-5D and ODI scores. The NRS scores also decreased however it was not statistically significant. Patients who had not undergone a medical procedure on the lumbar spine in the prehospital phase (Group B) had statistically significantly improved ODI and NRS scores. The average EQ-5D score decreased however, there was no statistically significant difference before and after scores in Group B. There was no statistically significant difference in variation in EQ-5D, ODI, and NRS scores before and after treatment between the groups. Conclusion: The results of this study indicated that even after a bilateral procedure and surgery, when pain in patients with lumbar spine herniated intervertebral disc did not decrease, (as in failed back surgery syndrome), Korean medicine combination treatment of postoperative pain was helpful and there was improvement in daily life.

• Journal of Acupuncture Research
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• 제38권1호
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• pp.32-40
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• 2021

Background: The aim of this study was to evaluate the efficacy of Korean medicine combination treatment on recurrent neck pain after medical procedures. Methods: This retrospective study included 158 inpatients of the Daejeon Jaseng Hospital of Korean Medicine who were diagnosed with "Cervical disc disorder with radiculopathy (M50.1)" between December 14th, 2017 and May 29th, 2019. The patients were assigned to 1 of 2 groups based on whether they received medical procedures on the cervical spine at least once. Korean medicine combination treatment was evaluated using EuroQol-5 dimensions index (EQ-5D), numeric rating scale (NRS), and neck disability index (NDI) scores. Results: Before and after treatment, the patients who received medical procedures on the cervical spine at least once before admission (Group A) showed a statistically significant difference in the NDI and NRS scores but not in the EQ-5D scores. This was similar to the patients who had not received medical procedures on the cervical spine before admission (Group B) they showed a statistically significant difference in the NDI and NRS scores but not in the EQ-5D scores. When comparing the results of Group A and Group B before and after treatment, no statistically significant differences were observed in the EQ-5D, NDI, and NRS scores. Conclusion: Korean medicine combination treatment improves the neck functional disability of patients who suffer from recurrent neck pain despite patients having undergone medical procedures.

• Journal of Internet Computing and Services
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• 제8권1호
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• pp.47-55
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• 2007

In this paper, we propose and observe a system that adopts Common-MCS (Modulation and Coding Scheme) level over all layer and Independent-MCS level for each layer in the combined AMC-V-BLAST (Adaptive Modulation and Coding-Vertical-Bell-lab Layered Space-Time) system. Also, comparing with the combined system using Common-MCS level, we observe throughput performance improvement in case of Independent-MCS level. As a result of simulation, Independent-MCS level case adapts modulation and coding scheme for maximum throughput to each channel condition in separate layer, resulting in improved throughput compared to Common-MCS level case. Especially, the results show that the combined AMC-V-BLAST system with Independent-MCS level achieves a gain of 700kbps in $7{\sim}9dB$ SNR (Signal-to-Noise Ratio) range against using Common-MCS level. In addition, the combined AMC-V-BLAST system using MMSEnulling method with receive diversity is verified that the difference of throughput between Independent MCS level system and common MCS level system in $7dB{\sim}9dB$ SNR is about 350kbps more or less.

• Asian-Australasian Journal of Animal Sciences
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• 제16권4호
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• pp.489-493
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• 2003

Reproductive traits of sows are determined chiefly by the genetic background of the dam herself. Whether the breed of the serviced boars also contributes is not yet clear. A total of 8,946 litters of Landrace (L) sows from 68 farms were examined. Of these, 876, 1,260, and 6,810 litters were produced from natural mating with L, Yorkshire (Y), and Duroc (D) breeds, respectively. The birth litter size (BLS), weaning litter size (WLS), live born piglets (LBP), and survival rate % (SR), of every litter were recorded. A general linear-model procedure was followed to estimate the effects of boars' breed (B), parity (P) and B${\times}$P interaction on the reproductive traits of the sows. Results show that BLS, WLS, and LBP were all significantly (p<0.001) affected by B and P. SR% was significantly influenced by B but not by P. L sows crossbred with Y or purebred with L produced litters with higher BLS, WLS, and LBP values than those bred with D. Pure L breeding yielded litters with lower SR% than did crossbreeding with D, while the difference between SR% due to LY and that due to LD crossbreeding was not significant. The interaction of B with P was significant with respect to BLS, WLS, and LBP (p<0.001), but not SR%. No significant B effect on reproductive traits was measured in sows at their first parity; but at latter parities, LL or LY produced litters with similarly high BLS, WLS and LBP, which values were all significantly greater than those of LD litters. The breed of boar evidently affected the subsequent reproductive performance of L sows and this effect may be further manipulated by the parity effect. Breed differences in semen quality and the success of fetus development with different interactions of the genetic background with the uterus function of the sow that may contribute to these effects are discussed.