• The Journal of the Korea Contents Association
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• v.22 no.6
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• pp.92-103
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• 2022

This study was designed to explore the ways to improve the organization and implementation of the curriculum for the small rural middle schools. In order to do this, the situations and demands in organizing and operating the curriculum were analyzed through interviews and classroom observations. Having separated the country into 5 distinct regions and the cases of 10 small rural middle schools across these regions of the country were directly observed and analyzed. As a result of the study, it was necessary to prepare a fundamental solution to the following problems: 1) insufficient linkage between school levels of integrated operating schools in terms of curriculum, 2) lack of educational facilities and cultural space in rural areas in terms of local communities, and 3) supply and demand of teachers in small-scale middle schools in rural areas in terms of supply and demand of teachers. Based on the discussed issues, the following implications could be drawn for the improvement and support of school curriculum organization and implementation. Firstly, the autonomy in organizing and operating curriculums for small rural middle schools should be greatly expanded so that integrated schools or joint curriculums between schools can be operated in a robust manner. Secondly, it needs to strengthen the out-of-school support for small rural middle schools alongside local governments and local communities, including the operation of Edu buses and the construction of multipurpose educational and cultural centers. Finally, it is necessary to address the difficulties of operating circuit teachers by systematically expanding the pool of teachers and instructors, and managing teachers and instructors at the level of the local education office.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.25 no.4
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• pp.187-193
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• 2013

Thanks to the characteristic of high-rise buildings, the increase of wind speed according to the height of a building makes it possible to use high wind power resources, many countries led by some advanced nations are recently making steady and persistent effort in introducing small wind turbine systems as a step to lower electric power load in high-rise buildings. The aim of this research is to propose an optimum application process of a small wind turbine system in high-rise buildings. To achieve this goal, the case studies on the applications of high-rise and tall buildings were conducted and the best application among them was selected. On the basis of the case studies, an application process was proposed.

• Journal of Power Electronics
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• v.9 no.5
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• pp.757-771
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• 2009

This paper proposes a systematic approach to the modeling of the small-signal characteristics of three-phase bridge boost rectifiers under non-sinusoidal conditions. The main obstacle to the conventional synchronous d-q frame modeling approach is that it is unable to identify a steady-state under non-sinusoidal conditions. However, for most applications under non-sinusoidal conditions, the current loops of boost rectifiers are designed to have a bandwidth that is much higher than typical harmonics frequencies in order to achieve good current control for these harmonic components. Therefore a quasi-static method is applied to the proposed modeling approach. The converter small-signal characteristics developed from conventional synchronous frame modeling under different operating points are investigated and a worst case point is then located for the current loop design. Both qualitative and quantitative analyses are presented. It is observed that operating points influence the converter low frequency characteristics but hardly affect the dominant poles. The relationship between power stage parameters, system poles and zeroes is also presented which offers good support for the system design. Both the simulation and experimental results verified the analysis and proposed modeling approach. Finally, the practical case of a parallel active power filter is studied to present the modeling approach and the resultant regulator design procedure. The system performance further verifies the whole analysis.

• Structural Monitoring and Maintenance
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• v.5 no.1
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• pp.39-50
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• 2018

Taking three types of bridge bearings with diameter being 100 mm as examples, the theoretical analysis, the experimental research as well as the numerical simulation of these bearings is conducted. Since the normal compression and shear machines cannot be applied to the small-size bearings, an improved equipment to test the properties of these bearings is proposed and fabricated. Besides, the simulation of the bearings is conducted based on the explicit finite element software ANSYS/LS-DYNA, and some parameters of the bearings are modified in the finite element model to reduce the computation cost effectively. Results show that all the research methods are capable of revealing the fundamental properties of the small-size bearings, and a combined use of these methods can better catch both the integral properties and the inner detailed mechanical behaviors of the bearings.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.18 no.3
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• pp.193-196
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• 2015

A fecaloma refers to a mass of accumulated feces that is much harder than a mass associated with fecal impaction. Fecalomas are usually found in the rectosigmoid area. A 10-year-old male with chronic constipation was admitted because of increasing abdominal pain. An abdominal computed tomography scan and a simple abdominal x-ray revealed rapidly evolving mechanical obstruction in the small intestine. Most of the fecalomas are successfully treated by conservative methods such as laxatives, enemas and rectal evacuation. When conservative treatments have failed, surgical intervention may be needed. In this case, an emergency operation was performed and a $4{\times}3{\times}2.5cm$ fecaloma was found in the distal ileum. We thus report a case of ileal fecaloma inducing small bowel obstruction in a patient with chronic constipation, who required surgical intervention. When symptoms of acute small intestinal obstruction develop in a patient with chronic constipation, a fecaloma should be considered in differential diagnosis.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.12 no.10
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• pp.4703-4723
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• 2018

In recent years, dense small cell network has been deployed to address the challenge that has resulted from the unprecendented growth of mobile data traffic and users. It has proven to be a cost efficeient solution to offload traffic from macro-cells. Software defined heterogeneous wireless network can decouple the control plane from the data plane. The control signal goes through the macro-cell while the data traffic can be offloaded by small cells. In this paper, we propose a framework for cell virtualization and user association in order to satisfy versatile requirements of multiple tenants. In the proposed framework, we propose an interference graph partioning based virtual-cell association and customized physical-cell association for multi-homed users in a software defined small cell network. The proposed user association scheme includes 3 steps: initialization, virtual-cell association and physical-cell association. Simulation results show that the proposed virtual-cell association outperforms the other schemes. For physical-cell association, the results on resource utilization and user fairness are examined for mobile users and infrastructure providers.

• Investigative Magnetic Resonance Imaging
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• v.18 no.4
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• pp.362-365
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• 2014

Predominant involvement of a particular group of fingers due to a central nervous system lesion has been described as pseudoperipheral palsy. Two patients visited our hospital with isolated weakness of a particular group of fingers due to small cortical infarctions. A 51-year-old woman suddenly developed weakness in her left index and middle fingers. The brain MRI showed a small infarct in the right frontal cortex. A 67-year-old man was sudden difficulty using his chopsticks and had weakness in his right thumb and index finger. The brain MRI showed a small infarct in the left precentral cortex.

• Bulletin of the Korean Chemical Society
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• v.35 no.4
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• pp.1159-1164
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• 2014

A simple, highly sensitive and selective method based on the rhodamine B-covered gold nanoparticle with dual-readout (colorimetric and fluorometric) detection for $\small{L}$-cysteine is proposed. A mechanism is that citrate-stabilized AuNPs were modified with RB by electrostatic interaction, which enables the nanometal surface energy transfer (NSET) from the RB to the AuNPs, quenching the fluorescence. In the presence of $\small{L}$-cysteine, it was used as a competitor in the NSET by the strongly Au-S bonding to release RB from the Au surface and recover the fluorescence, and the red-to-purple color change quickly, which was monitored simply by the naked eye. Under the optimum conditions, the detection limit is as low as 10 nM. The method possessed the advantages of simplicity, rapidity and sensitivity at the same time. The method was also successfully applied to the determination of $\small{L}$-cysteine in human urine samples, and the results were satisfying.

• Journal of Veterinary Clinics
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• v.24 no.2
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• pp.229-232
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• 2007

A 7-year-old Shih Tzu cross dog was presented for severe abdominal pain, persistent vomiting and anorexia. Laboratory tests revealed mild anemia and hypoproteinemia. Abdominal survey radiography revealed marked gastric distension and large circular foreign body in the gastric pylorus. The foreign body was removed using a videoendoscope, fishing line and retrieval forceps. The dog's clinical signs resolved following foreign body removal.

• Journal of Korean Dental Science
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• v.12 no.1
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• pp.20-28
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• 2019

Purpose: This study was performed to evaluate the effect of voxel size on the accuracy of landmark identification in cone-beam computed tomography (CBCT) images. Materials and Methods: CBCT images were obtained from 15 dry human skulls with two different voxel sizes; 0.39 mm and 0.10 mm. Three midline landmarks and eight bilateral landmarks were identified by 5 examiners and were recorded as three-dimensional coordinates. In order to compare the accuracy of landmark identification between large and small voxel size images, the difference between best estimate (average value of 5 examiners' measurements) and each examiner's value were calculated and compared between the two images. Result: Landmark identification errors showed a high variability according to the landmarks in case of large voxel size images. The small voxel size images showed small errors in all landmarks. The landmark identification errors were smaller for all landmarks in the small voxel size images than in the large voxel size images. Conclusion: The results of the present study indicate that landmark identification errors could be reduced by using smaller voxel size scan in CBCT images.