• Carbon letters
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• v.15 no.2
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• pp.77-88
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• 2014

Double walled carbon nanotubes (DWCNTs) are considered an ideal model for studying the coupling interactions between different concentric shells in multi-walled CNTs. Due to their intrinsic coaxial structures they are mechanically, thermally, and structurally more stable than single walled CNTs. Geometrically, owing to the buffer-like function of the outer tubes in DWCNTs, the inner tubes exhibit exciting transport and optical properties that lend them promise in the fabrication of field-effect transistors, stable field emitters, and lithium ion batteries. In addition, by utilizing the outer tube chemistry, DWCNTs can be useful for anchoring semiconducting quantum dots and also as effective multifunctional fillers in producing tough, conductive transparent polymer films. The inner tubes meanwhile preserve their excitonic transitions. This article reviews the synthesis of DWCNTs, their electronic structure, transport, and mechanical properties, and their potential uses.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.5
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• pp.609-624
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• 2013

The objective of this study was to get a comprehensive understanding of how genes in chicken shell gland modulate eggshell strength at the early stage of active calcification. Four 32-week old of purebred Xianju hens with consistent high or low shell breakage strength were grouped into two pairs. Using Affymetrix Chicken Array, a whole-transcriptome analysis was performed on hen's shell gland at 9 h post oviposition. Gene ontology enrichment analysis for differentially expressed (DE) transcripts was performed using the web-based GOEAST, and the validation of DE-transcripts was tested by qRT-PCR. 1,195 DE-transcripts, corresponding to 941 unique genes were identified in hens with strong eggshell compared to weak shell hens. According to gene ontology annotations, there are 77 DE-transcripts encoding ion transporters and secreted extracellular matrix proteins, and at least 26 DE-transcripts related to carbohydrate metabolism or post-translation glycosylation modification; furthermore, there are 88 signaling DE-transcripts. GO term enrichment analysis suggests that some DE-transcripts mediate reproductive hormones or neurotransmitters to affect eggshell quality through a complex suite of biophysical processes. These results reveal some candidate genes involved with eggshell strength at the early stage of active calcification which may facilitate our understanding of regulating mechanisms of eggshell quality.

• Structural Engineering and Mechanics
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• v.65 no.3
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• pp.349-357
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• 2018

An extensive research was undertaken to study the vibration serviceability of a long-span and light-weight floor subjected to human loading experimentally and numerically. Specifically, heel-drop test was first conducted to capture the floor's natural frequencies and damping ratios, followed by jumping and running tests to obtain the acceleration responses. In addition, numerical simulations considering walking excitation were performed to further evaluate the vibration performance of a multi-panel floor under different loading cases and walking rates. The floor is found to have a high frequency (11.67 Hz) and a low damping ratio (2.32%). The comparison of the test results with the published data from the 1997 AISC Design Guide 11 indicates that the floor exhibits satisfactory vibration perceptibility overall. The study results show that the peak acceleration is affected by the walking path, walking rate, and adjacent structure. A simpler loading case may be considered in design in place of a more complex one.

• The Plant Pathology Journal
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• v.30 no.2
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• pp.151-158
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• 2014

Three double-stranded RNAs (dsRNAs), approximately 1.85, 1.65 and 1.27 kb in size, were detected in an isolate of Cytospora sacchari from Iran. Partial nucleotide sequence revealed a 1,284 bp segment containing one ORF that potentially encodes a 405 aa protein. This protein contains conserved motifs related to RNA dependent RNA polymerases (RdRp) that showed similarity to RdRps of partitiviruses. The results indicate that these dsRNAs represent a novel Partitivirus that we tentatively designate Cytospora sacchari partitivirus (CsPV). Treatment of the fungal strain by cyclohexamide and also hyphal tip culture had no effect on removing the putative virus. Phylogenetic analysis of putative RdRp of CsPV and other partitiviruses places CsPV as a member of the genus Partitivirus in the family Partitiviridae, and clustering with Aspergillus ochraceous virus 1.

• Health Policy and Management
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• v.16 no.4
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• pp.147-168
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• 2006

Technological innovation has been regarded as the core competence for the economic growth of individual, as well as organization and country. Pharmaceutical innovation, what we call new medicines, influence people's longevity and productivity by increasing output per hour worked. Therefore, using claims data on virtually all the drugs and diseases of over 550,000 people enrolled in National Health Insurance Program in Korea, we examined the impact of the vintage (original FDA and KFDA approval year) of drugs used to treat a patients from July 1st to December 31st in 2002 on the patient's mortality at the end of 2004, controlling for demographic characteristics(age and sex), utilization of medical services, and the nature and complexity of illness. We found that people using newer drugs are less likely to die at the end of 2004, conditional on covariates. The estimated mortality rates were declining with respect to drug vintage for 1970s, 1980s and 1990s and highly significant. In addition to estimating the model for the entire sample, we estimated the model separately for several disease categories classified by Korean Classification of Disease. Estimates of three drug vintage variables for subgroups of people with (1)neoplasms, (2)endocrine, nutritional and metabolic diseases, and (3)the diseases of circulatory system displayed similar patterns.

• Molecules and Cells
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• v.22 no.1
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• pp.78-88
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• 2006

The phylogeny of the subfamily Tephritinae (Diptera: Tephritidae) was reconstructed from mitochondrial 16S ribosomal RNA gene sequences using 53 species representing 11 currently recognized tribes of the Tephritinae and 10 outgroup species. The minimum evolution and Bayesian trees suggested the following phylogenetic relationships: (1) monophyly of the Tephritinae was strongly supported; (2) a sister group relationship between the Tephritinae and Plioreocepta was supported by the Bayesian tree; (3) the tribes Tephrellini, Myopitini, and Terelliini (excluding Neaspilota) were supported as monophyletic groups; (4) the non-monophyletic nature of the tribes Dithrycini, Eutretini, Noeetini, Tephritini, Cecidocharini, and Xyphosiini; and (5) recognition of 10 putative tribal groups, most of which were supported strongly by the statistical tests of the interior branches. Our results, therefore, convincingly suggest that an extensive rearrangement of the tribal classification of the Tephritinae is necessary. Since our sampling of taxa heavily relied on the current accepted classification, some lineages identified by the present study were severely under-sampled and other possible major lineages of the Tephritinae were probably not even represented in our dataset. We believe that our results provide baseline information for a more rigorous sampling of additional taxa representing all possible major lineages of the subfamily, which is essential for a comprehensive revision of the tephritine tribal classification.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.55 no.12
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• pp.561-569
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• 2006

Because of the trend of deregulation, power industry is going through an unprecedented transformation in North America and Europe, and there are a host of acquisitions and mergers by the private sector to position themselves to take advantage of new business opportunities. Deregulation has accelerated the development of smaller generators and fuel cells will gradually become more attractive to mainstream electricity users as they improve in capability and decrease in cost. Fuel Cell technology is surveyed and the potential of using fuel cell as a distributed generation source is presented. This paper recommends the fuel cell power plants as alternative energy sources for distributed generation in Jeju Island, Korea. This will help in increasing fuel efficiency, at least double the current thermal plants', increasing the reliability of power supply, reducing the dependency on the HVDC link, providing quality power to the growing infrastructure, and maintaining clean air in meeting the free-trade international island.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2007.04a
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• pp.71-74
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• 2007

Large Eddy Simulation(LES) has been conducted to insight interaction effects of turbulent flow and chemical reaction of a lean-Premixed swirl combustor. The unsteady turbulent flame is carefully simulated so that the motion of flow and flame can be characterized in detail. Fuel lumps escaping from the primary combustion zone move downstream and consequently produce local hot spots conveying large vortical structures in the azimuthal direction. The correlation between pressure oscillation and unsteady heat release is examined by the spatial and temporal Rayleigh parameter.

• Journal of The Korean Society of Agricultural Engineers
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• v.49 no.1
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• pp.35-42
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• 2007

This paper develops a Sustainable Regional Economic Growth Model (SREG) which estimates the relation of labor population change and employment increase in each occupation and maximum limits and minimum requirements of employment increase by labor population change in a specified region using multiplier theory. To develop the proposed model, sustainable regional economic growth is defined as a steady increase of labor population over a long term period and the limit of employment increase is defined as the estimated labor population change in the region with no need for commutation from the surrounded areas. Developed model was applied to 67 county in Pennsylvania State and the results revealed that the investment in infrastructure occupations, such as transportation, warehousing, utilities, information, communication, and other public utilities, maximizes the effects for increasing employment, whereas finance, insurance, and real estate occupations have minimum effects for increasing employment. Calculated minimum requirements of occupations show that infra-structure occupations is a critical factor for labor population change and maximum limits of occupations show that agriculture and finance occupations are difficult to increase independently.

• Journal of The Korean Society of Agricultural Engineers
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• v.56 no.5
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• pp.29-36
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• 2014

The purpose of this study is to improve the Generic Agricultural Systems Simulator (GASS) which can simulate various rural systems based on object-oriented model. GASS provides the configuration platform of various system components to simplify integrated agricultural system models such as irrigation systems for rice farming. The new connection and communication modules of GASS improve applicability for modelling diverse systems. The geometric connection of GASS replaces topological connection, and communication protocols expand to analyze not only homogeneous system but also heterogeneous system. In this paper, we applied GASS2 to simulate the water heights of linked tanks and the simulation outputs were verified through comparing with analytical solutions of differential equations. The two new modules make it possible to analyze the 4-tank problem which includes topological and heterogenous issues with GASS2.