• Journal of Communications and Networks
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• v.18 no.6
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• pp.926-937
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• 2016

In this paper, we study the feasibility of receiver diversity for application to downlink cellular networks, where low-energy devices are equipped with information decoding and energy harvesting receivers for simultaneous wireless information and power transfer. We compare several options that are based on selection combining and maximum ratio combining, which provide different implementation complexities. By capitalizing on the Frechet inequality, we shed light on the advantages and limitations of each scheme as a function of the transmission rate and harvested power that need to be fulfilled at the low-energy devices. Our analysis shows that no scheme outperforms the others for every system setup. It suggests, on the other hand, that the low-energy devices need to operate in an adaptive fashion, by choosing the receiver diversity scheme as a function of the imposed requirements. With the aid of stochastic geometry, we introduce mathematical frameworks for system-level analysis. We show that they constitute an important tool for system-level optimization and, in particular, for identifying the diversity scheme that optimizes wireless information and power transmission as a function of a sensible set of parameters. Monte Carlo simulations are used to validate our findings and to illustrate the trade-off that emerge in cellular networks with simultaneous wireless information and power transfer.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2005.05a
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• pp.82-85
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• 2005

In order to see the effect of die deformation on the forming of sheet metal, the draw-ins, strains, and springbacks of an automotive fender panels are numerically simulated considering the die deformation found by the simultaneous structural analysis of press and dies. The comparison of the forming analysis result between the rigid die and the deformed die layout shows that the deformed tool provides more accurate forming and springback result.

• Journal of Digital Convergence
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• v.10 no.6
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• pp.331-339
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• 2012

The easy and simple simultaneous analytical method of preservatives (BA, SA, DHA, MP, EP, IPP, PP, IBP and BP) was studied by more easily changing from method used in food and drug using HPLC with scherzo SM-C18 column. All presevatives were seperated successfully in mobile phase of 50 mM ammonium formate : 0.1% phosphoric acid (50:50 v/v%) and 50 mM ammonium formate : acetonitrile (30 : 70). Retention time of BA, SA, DHA, MP, EP, IPP, PP, IBP and BP was 7.74, 9.08, 12.57, 13.83, 21.62, 27.29, 28.20, 33.20 and 33.68 min, respectively. The calibration curves of BA, SA, DHA, MP, EP, IPP, PP, IBP and BP were linear over the concentration range of 5~80 ${\mu}g/mL$ with correlation coefficient of above 0.999. The limit of detection (LOD) and limit of quantitation (LOQ) of BA, SA, DHA, MP, EP, IPP, PP, IBP and BP were 0.52 and 1.58, 1.09 and 3.29, 1.00 and 3.03, 1.36 and 4.13, 1.26 and 3.83, 1.02 and 3.08, 1.11 and 3.37, 0.82 and 2.48, 0.85 and 2.59 ${\mu}g/mL$, respectively. The coefficients of variation for intra- and inter-day assay were 0.12~2.68 and 0.18~2.66%, respectively. The developed method showed good intra- and inter-day precision and accuracy. The preservatives used in mouthwashes were BA, MP and PP and were detected in 24 samples(86%) except for 4 samples and not showed significant difference in using dose of adult and children. In conclusion, the developed method can be useful for simultaneous analysis of preservatives in mouthwashes and these results suggest that could be applied to fundamental study and guideline on content of preservatives in mouthwashes.

• Herbal Formula Science
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• v.21 no.1
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• pp.71-79
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• 2013

Objectives : Yijin-tang has been used in the treatment of gastrointestinal diseases such as irritable bowel syndrome, gastritis, and gastric ulcer. In this study, a high-performance liquid chromatography (HPLC) method was established for simultaneous analysis of six compounds, liquiritin, glycyrrhizin, hesperidin, 6-gingerol, homogentisic acid, and 3,4-dihydroxybenzaldehyde in Yijin-tang, a traditional Korean herbal medicinal preparation. Methods : A Gemini C18 column was used for the separation of six constituents at $40^{\circ}C$. The mobile phase using gradient elution consist of two solvent systems, 1.0% acetic acid in water (A) and 1.0% acetic acid in acetonitrile (B). The flow-rate was 1.0 mL/min and injection volume was $10{\mu}g$. The detector was a photodiode array (PDA) detector set at 254 nm and 280 nm. Results : The calibration curves of six compounds showed good linearity in various concentration ranges ($R^2{\geq}0.9997$). The limits of detection (LOD) and limits of quantification (LOQ) were 0.028-$0.192{\mu}g/mL$ and 0.093-$0.540{\mu}g/mL$, respectively. The RSD (%) of the intra and inter day validations were 0.03-0.84% and 0.05 -1.00%, respectively. Recovery was 96.14-01.90% and RSD (%) was less than 1.5%. Conclusions : The established simultaneous analysis methods will help management to improve the quality of Yijin-tang.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.4
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• pp.1665-1669
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• 2015

Background: The optimal surgical strategy for the treatment of synchronous resectable gastric cancer liver metastases remains controversial. The aims of this study were to analyze the outcome and overall survival of patients presenting with gastric cancer and liver metastases treated by simultaneous resection. Materials and Methods: Between January 1990 and June 2009, 35 patients diagnosed with synchronous hepatic metastases from gastric carcinoma received simultaneous resection of both primary gastric cancer and synchronous hepatic metastases. The clinicopathologic features and the surgical results of the 35 patients were retrospectively analyzed. Results: The 5-year overall survival rate after surgery was 14.3%. Five patients survived for more than 5 years after surgery. No mortality has occurred within 30 days after resection, although two patients (5.7%) developed complications during the peri-operative course. Univariate analysis revealed that patients with the presence of lymphovascular invasion of the primary tumor, bilateral liver metastasis and multiple liver metastases suffered poor survival. Lymphovascular invasion by the primary lesion and multiple liver metastases were significant prognostic factors that influenced survival in the multivariate analysis (p=0.02, p=0.001, respectively). Conclusions: The presence of lymphovascular invasion of the primary tumor and multiple liver metastases are significant prognostic determinants of survival. Gastric cancer patients without lymphovascular invasion and with a solitary synchronous liver metastasis may be good candidates for hepatic resection. Simultaneous resection of both primary gastric cancer and synchronous hepatic metastases may effectively prolong survival in strictly selected patients.

• Journal of radiological science and technology
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• v.43 no.6
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• pp.481-487
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• 2020

Radiation measurement technology has steadily improved and its usage is expanding in various industries such as nuclear medicine, security search, satellite, nondestructive testing, environmental industries and the domain of nuclear power plants (NPPs). Especially, the simultaneous measurements of gamma rays and neutrons can be even more critical for nuclear safety management of spent nuclear fuel and monitoring of the nuclear material. A semiconductor detector comprising cadmium, zinc, and tellurium (CZT) enables to detect gamma-rays due to the significant atomic weight of the elements via immediate neutron and gamma-ray detection. Semiconductor sensors might be used for nuclear safety management by monitoring nuclear materials and spent nuclear fuel with high spatial resolution as well as providing real-time measurements. We aim to introduce a portable nuclide-analysis device that enables the simultaneous measurements of neutrons and gamma rays using a CZT sensor. The detector has a high density and wide energy band gap, and thus exhibits highly sensitive physical characteristics and characteristics are required for performing neutron and gamma-ray detection. Portable nuclide-analysis device is used on NPP-decommissioning sites or the purpose of nuclear nonproliferation, it will rapidly detect the nuclear material and provide radioactive-material information. Eventually, portable nuclide-analysis device can reduce measurement time and economic costs by providing a basis for rational decision making.

• Journal of The Korean Astronomical Society
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• v.52 no.1
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• pp.23-30
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• 2019

The KVN(Korean VLBI Network)-style simultaneous multi-frequency receiving mode is demonstrated to be promising for mm-VLBI observations. Recently, other Very long baseline interferometry (VLBI) facilities all over the globe start to implement compatible optics systems. Simultaneous dual/multi-frequency VLBI observations at mm wavelengths with international baselines are thus possible. In this paper, we present the results from the first successful simultaneous 22/43 GHz dual-frequency observation with KaVA(KVN and VERA array), including images and astrometric results. Our analysis shows that the newly implemented simultaneous receiving system has brought a significant extension of the coherence time of the 43 GHz visibility phases along the international baselines. The astrometric results obtained with KaVA are consistent with those obtained with the independent analysis of the KVN data. Our results thus confirm the good performance of the simultaneous receiving systems for the nonKVN stations. Future simultaneous observations with more global stations bring even higher sensitivity and micro-arcsecond level astrometric measurements of the targets.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.36 no.6
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• pp.407-414
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• 2023

In this study, an automated jack-up system, applicable to various fields, was employed for 3D concrete printing and developed as a simultaneous liftable 3D concrete printing system. This developed printing system enables safe and precise jack-up by monitoring the measured jack-up distance using Pearson correlation coefficient analysis and a hydraulic system with interquartile range analysis in real-time during 3D concrete printing operations. It is possible to secure the quality of 3D concrete printing structures, which is essential for expanding the application of 3D concrete printing to construct larger structures. Specimens were printed using both conventional 3D concrete printing and simultaneous liftable 3D concrete printing to evaluate the system performance. The printed specimens were investigated using a 3D scanner. The layer-wise diameter and angle of intersection of the scanned specimens were measured, and an analysis was performed to verify the advantages of the simultaneous liftable 3D concrete printing.

• Structural Engineering and Mechanics
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• v.65 no.3
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• pp.233-241
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• 2018

In this paper, the Colliding Bodies Optimization (CBO), Enhanced Colliding Bodies Optimization (ECBO) and Vibrating Particles System (VPS) algorithms and the force method are used for the simultaneous analysis and design of truss structures. The presented technique is applied to the design and analysis of some planer and spatial trusses. An efficient method is introduced using the CBO, ECBO and VPS to design trusses having members of prescribed stress ratios. Finally, the minimum weight design of truss structures is formulated using the CBO, ECBO and VPS algorithms and applied to some benchmark problems from literature. These problems have been designed by using displacement method as analyzer, and here these are solved for the first time using the force method. The accuracy and efficiency of the presented method is examined by comparing the resulting design parameters and structural weight with those of other existing methods.

• Natural Product Sciences
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• v.16 no.3
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• pp.180-184
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• 2010

The simple and accurate method was established for the simultaneous determination of (-)-menthone and (-)-menthol in Menthae herba obtained from Korea and China. A quantitative analysis was performed with a gas chromatography-flame ionization detector and reference compounds were separated on a capillary HP-Innowax column (30 m $\times$ 0.23 mm, 0.50 ${\mu}m$, Agilent, MA, USA). The correlation coefficients of the compounds showed good linearity ($r^2$ > 0.9997) over the linear range. The precision, repeatability and stability showed less than 1.7% of relative standard deviation (RSD) values for two compounds. Recovery rates were within the range of 95.72 - 103.76%. The method was applied successfully to analyze 15 samples of Menthae herba and achieved sufficient and specific separation of reference compounds. The principal component analysis (PCA) exhibited the classification of 15 samples according to their locations of origin.