• Korean Journal of Materials Research
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• v.3 no.3
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• pp.237-244
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• 1993

The characteristics of composite polymer electrolytes obtained by adding a fine ceramic powder($\gamma-{LiAlO}_{2}$) with a diameter of $1{\mu}$m to a poly(ethylene oxide)/lithium trifluoromethane sulfonate (LiC$F_3$S$O_3$) complex are described in terms of morphological and mechanical behavior. The addition of uniformly dispersed ceramic powder greatly improves the electrical and mechanical properties of solid polymer electrolytes at ambient temperature. For the composite polymer electrolytes under this study, the optimum composition of the $\gamma-{LiAIO}_{2}$ in the composite for maximum ionic conductivity was found to be 20 wt%.

• Analytical Science and Technology
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• v.9 no.3
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• pp.292-301
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• 1996

The synthesis of poly(ether)tailed bipyridine complex as redox reaction probes has advanced attempts to interpret very slow diffusion and heterogeneous electron transfer. Diffusion coefficients as low as $1.5{\times}10^{-15}cm^2/s$ have been observed for the oxidation of neat $Co(bpy(ppgm)_2)_{3^-}(ClO_4)_2$ with $LiClO_4$ electrolyte. Heterogeneous electron transfer rate constants of materials were found to vary with diffusion coefficient. The decrease in k as the diffusion coefficient decreases was actually caused by the decreasing D. Diffusion coefficient for compound of strong ion pairing anion($ClO{_4}^-$) was much smaller than the diffusion coefficient for compound of weak ion pairing anion($CF_3COO^-$).

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.26 no.3
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• pp.227-239
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• 2008

Processing LiDAR (Light Detection And Ranging) data obtained from ALS (Airborne Laser Scanning) systems mainly involves organization and segmentation of the data for 3D object modeling and mapping purposes. The ALS systems are viable and becoming more mature technology in various applications. ALS technology requires complex integration of optics, opto-mechanics and electronics in the multi-sensor components, Le. data captured from GPS, INS and laser scanner. In this study, digital image processing techniques mainly were implemented to gray level coded image of the LiDAR data for building extraction and superstructures segmentation. One of the advantages to use gray level image is easy to apply various existing digital image processing algorithms. Gridding and quantization of the raw LiDAR data into limited gray level might introduce smoothing effect and loss of the detail information. However, smoothed surface data that are more suitable for surface patch segmentation and modeling could be obtained by the quantization of the height values. The building boundaries were precisely extracted by the robust edge detection operator and regularized with shape constraints. As for segmentation of the roof structures, basically region growing based and gap filling segmentation methods were implemented. The results present that various image processing methods are applicable to extract buildings and to segment surface patches of the superstructures on the roofs. Finally, conceptual methodology for extracting characteristic information to reconstruct roof shapes was proposed. Statistical and geometric properties were utilized to segment and model superstructures. The simulation results show that segmentation of the roof surface patches and modeling were possible with the proposed method.

• Journal of Korean Society for Geospatial Information Science
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• v.18 no.2
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• pp.29-33
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• 2010

The purpose of LiDAR ground classification is to archive both goals which are acquiring confident ground points with high precision and describing ground shape in detail. In spite of many studies about developing optimized algorithms to kick out this, it is very difficult to classify ground points and describing ground shape by airborne LiDAR data. Especially it is more difficult in a dense forested area like Korea. Principle misclassification was mainly caused by complex forest canopy hierarchy in Korea and relatively coarse LiDAR points density for ground classification. Unfortunately, a lot of LiDAR surveying performed in summer in South Korea. And by that reason, schematic LiDAR points distribution is very different from those of Europe. So, this study propose enhanced ground classification method considering Korean land cover characteristics. Firstly, this study designate highly confident candidated LiDAR points as a first ground points which is acquired by using big roller classification algorithm. Secondly, this study applied weighted gradient kernel(WGK) algorithm to find and include highly expected ground points from the remained candidate points. This study methods is very useful for reconstruct deformed terrain due to misclassification results by detecting and include important terrain model key points for describing ground shape at site. Especially in the case of deformed bank side of river area, this study showed highly enhanced classification and reconstruction results by using WGK algorithm.

• The Korea Journal of Herbology
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• v.30 no.3
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• pp.25-34
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• 2015

Objectives : This study was performed to investigate the efficacy and safety of the Mulberry Extract Complex in a placebo-controlled randomized clinical trial and animal study on degenerative arthritis. Methods : Animal study: Mulberry Extract Complex is composed of extracts of mulberry (Morus alba L.) fruit, mulberry leaves and black beans (Glycine max (L.) Merr.). To evaluate the serum level of interleukin-2, interferon-$\gamma$, and prostaglandin E2, an animal model of degenerative arthritis induced by monosodium iodoacetate was employed. Clinical study: The efficacy index (VAS, K-WOMAC) was compared among patients with symptoms of degenerative arthritis before and after Mulberry Extract Complex ingestion as well as the one in groups. Evaluations of the improvement by the subjects and by doctor assessment were also performed. Results : Animal study: Mulberry Extract Complex reduced the serum level of interferon-$\gamma$ and prostaglandin E2 in an animal model with degenerative arthritis. Clinical study: The VAS change showed statistical significance in the experimental groups after 4 weeks (PP set) and 8 weeks (ITT set) of ingestion. When the K-WOMAC was analyzed using a modified ITT set to determine the effectiveness, statistically significant results were obtained in the fields of pain & symptom within the Mulberry Extract Complex group as well as between the Mulberry Extract Complex and placebo groups after 8 weeks of ingestion. Results from the improvement evaluation by subjects and the assessment of improvement by doctors showed statistical significance in the experimental groups (PP set) after 8 weeks. Conclusions : Mulberry Extract Complex could be useful for the improvement of various symptoms of degenerative arthritis based on its anti-inflammatory activity and its reduction of VAS and K-WOMAC pain scores.

• Bulletin of the Korean Chemical Society
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• v.34 no.12
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• pp.3743-3748
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• 2013

A tetradentate ligand of 2-phenyl-4,6-di(pyridin-2-yl)pyrimidine (L) has been synthesized and its complexes with $ZnI_2$ and CuI have been obtained by hydrothermal method. single crystal X-ray diffraction analysis indicates that ligand L coordinates with Zn(II) ions to form a simple four-coordinate di-nuclear complex, while the complexation of L with Cu(I) constructs a one-dimensional chain polymer. The existence of $I^-$ ion hampers the L to assemble grid-type complexes with Zn(II) and Cu(I). Fluorescence spectra show that the L emits blue fluorescence while its Cu(I) polymer decrease the fluorescence intensity and Zn(II) complex quenches the fluorescence.

• Journal of Communications and Networks
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• v.15 no.5
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• pp.496-503
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• 2013

In an orthogonal frequency division multiplexing system, conventional interpolation techniques cannot correctly balance performance and overhead when estimating dynamic long-delay channels in single frequency networks (SFNs). In this study, classical filter analysis and design methods are employed to derive a complex interpolator for maximizing the resistible echo delay in a channel estimator on the basis of the correlation between frequency domain interpolating and time domain windowing. The coefficient computation of the complex interpolator requires a key parameter, i.e., channel length, which is obtained in the frequency domain with a tentative estimation scheme having low implementation complexity. The proposed complex adaptive interpolator is verified in a simulated digital video broadcasting for terrestrial/handheld receiver. The simulation results indicate that the designed channel estimator can not only handle SFN echoes with more than $200{\mu}s$ delay but also achieve a bit-error rate performance close to the optimum minimum mean square error method, which significantly outperforms conventional channel estimation methods, while preserving a low implementation cost in a short-delay channel.

• International Journal of High-Rise Buildings
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• v.10 no.3
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• pp.203-210
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• 2021

With the development of urbanization, the increasing of buildings density in urban core areas result in the complexity of construction environment. High-rise landmark building is always preferred in the construction of urban core areas. Super high-rise buildings construction are facing construction management difficulties due to the complex working conditions and enormous building system, especially with the complex surrounding environment of the urban core area, the construction management of super high-rise buildings in the area requires higher, refined and detailed standard. Based on a super high-rise project in a core area of Shanghai which has 370 m building height and 772,643 m² building area, with complex surrounding environment, narrow construction site and many super-high-altitude crossing works. With the application of BIM technology, the Internet of Things, the LAN communication and other various intelligent mechanical equipment, information management systems, the efficiency and refinement of construction management are improved, ensuring the smooth implementation of the project while effectively controlling the impact on the surrounding environment.

• Nuclear Engineering and Technology
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• v.56 no.6
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• pp.1959-1974
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• 2024

Nuclear energy plays a crucial role in energy supply in the 21st century, and more and more Nuclear Power Plants (NPPs) will be in operation to contribute to the development of human society. However, as a typical complex system engineering, the operation and development of NPPs require efficient and stable control methods to ensure the safety and efficiency of nuclear power generation. Reinforcement learning (RL) aims at learning optimal control policies via maximizing discounted long-term rewards. The reward-oriented learning paradigm has witnessed remarkable success in many complex systems, such as wind power systems, electric power systems, coal fire power plants, robotics, etc. In this work, we try to present a systematic review of the applications of RL on these complex systems, from which we believe NPPs can borrow experience and insights. We then conduct a block-by-block investigation on the application scenarios of specific tasks in NPPs and carried out algorithmic research for different situations such as power startup, collaborative control, and emergency handling. Moreover, we discuss the possibilities of further application of RL methods on NPPs and detail the challenges when applying RL methods on NPPs. We hope this work can boost the realization of intelligent NPPs, and contribute to more and more research on how to better integrate RL algorithms into NPPs.

• Journal of Korean Neurosurgical Society
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• v.30 no.4
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• pp.430-436
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• 2001

Objective : The proliferative potential of intracranial glioma affects the histological malignancy and prognosis of patients with these tumors. In this study, we present the relationship between MIB-1 labeling index(LI) and clinical variables which might play the major role in determining the prognosis of patient with astrocytic tumors. Patients and Methods : Excised tumor specimens from a total of 52 patients were stained to detect monoclonal MIB-1-Ki-67 antibody by avidin-biotin complex immunohistochemistry. The MIB-1 LI was evaluated with histological grades, demograpghic data, and survival time. The statistical significance of their correlation was analyzed by Pearson correlation test. Results : The 52 patients included 30 male patients and 22 female patients. The tumors according to the criteria of the World Health Organization(WHO) classification were verified as pleomorphic xanthoastrocytoma in one, pilocytic astrocytomas 4, astrocytomas 1, anaplastic astrocytomas 3, and glioblastomas 31. MIB-1 LI in astrocytic ttumors showed no correlation with age and gender. However, the patients under 10 years had the longest survival time, whereas short survival time was observed in the older patients. The mean MIB-1 LI of different tumor grades were as follows : pleomorphic xanthoastrocytoma, $4.40{\pm}0.00$ ; pilocytic astrocytoma, $4.53{\pm}3.09$ ; astrocytoma, $5.50{\pm}6.03$ ; anaplastic astrocytoma, $12.68{\pm}12.50$ ; Glioblastoma, $21.31{\pm}19.63$. Although the levels of MIB-1 LI were varied in individual tumors, the MIB-1 LI was increased in parallel with the histological grades. Glioblstomas showed significantly higher MIB-1 LI compared with that of anaplastic astrocytomas and low grade astrocytomas (p = 0.001). The mean survival time of entire group of patients was also well correlated with MIB-1 LI in astrocytic tumors(p = 0.015). Moreover, the mean survival time of the entire group of patients with Lis < 10 was $125.33{\pm}113.57weeks$, and the mean survival of those with $Lis{\geq}10$ was $60.71{\pm}62.58weeks$. This difference was also statistically significant(p = 0.004). Conclusion : The results of this study suggest that MIB-1 LI correlates with histological grades and might play a significant role in predicting the survival of patients with astrocytic tumors.