• 제목/요약/키워드: The Christopher

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Reconstruction of a near-surface tornado wind field from observed building damage

  • Luo, Jianjun;Liang, Daan;Weiss, Christopher
    • Wind and Structures
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    • 제20권3호
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    • pp.389-404
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    • 2015
  • In this study, residential building damage states observed from a post-tornado damage survey in Joplin after a 2011 EF 5 tornado were used to reconstruct the near-surface wind field. It was based on well-studied relationships between Degrees of Damage (DOD) of building and wind speeds in the Enhanced Fujita (EF) scale. A total of 4,166 one- or two-family residences (FR12) located in the study area were selected and their DODs were recorded. Then, the wind speeds were estimated with the EF scale. The peak wind speed profile estimated from damage of buildings was used to fit a translating analytical vortex model. Agreement between simulated peak wind speeds and observed damages confirms the feasibility of using post-tornado damage surveys for reconstructing the near-surface wind field. In addition to peak wind speeds, the model can create the time history of wind speed and direction at any given point, offering opportunity to better understand tornado parameters and wind field structures. Future work could extend the method to tornadoes of different characteristics and therefore improve model's generalizability.

Thidiazuron Induced High Frequency Adventitious Shoot Formation and Plant Regeneration in Capsicum annuum L.

  • VENKATAIAH PEDDABOINA;CHRISTOPHER THAMIDALA;SUBHASH KARAMPURI
    • Journal of Plant Biotechnology
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    • 제5권4호
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    • pp.245-250
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    • 2003
  • An efficient procedure was developed for adventitious shoot bud induction and plantlet regeneration from various explants of the ten genotypes of Pepper (Capsicum annuum L.) using Thidiazuron (TDZ). Among various treatments at 1.0-3.0 mg/L TDZ Induced maximum number of adventitious shoots depending upon the explant type and genotype compared to other treatments. Among the explants tested, leaf induced maximum number of adventitious shoots than the cotyledons. TDZ-mediated organo-genesis was possible in 10 pepper cultivars, the extent of the response being genotype-dependent. Of the ten genotypes tested, C. annuum cvs CA960, $G_4$ and X-235 were produced maximum number of adventitious shoots and Sell was the least, and all other genotypes gave moderate response. Elongation of multiple shoots was observed on medium supplemented with SA (0.05 mg/L) in combination of IAA (0.05 mg/L). Differences in ability for in vitro shoot regeneration and elongation depend upon the variety and explant type. The elongated shoots were success. Fully rooted on MS medium containing at 1.0 mG/L IAA. Plantlets regenerated from different explants of ten genotypes were found to be diploid (2n=24) and were devoid of any chromosomal aberrations. Regenerated plants were successfully established in soil where 85-90% of them developed into morphologically normal and fertile plants.

A molecular-assisted alpha taxonomic study of the genus Centroceras (Ceramiaceae, Rhodophyta) in Bermuda reveals two novel species

  • Schneider, Craig W.;Cianciola, Elisabeth N.;Popolizio, Thea R.;Spagnuolo, Dylan S.;Lane, Christopher E.
    • ALGAE
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    • 제30권1호
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    • pp.15-33
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    • 2015
  • When the generitype Centroceras clavulatum, a presumed cosmopolitan warm temperate to tropical red alga, was discovered to have a biogeographic distribution limited to the Pacific Ocean using molecular and morphological evidence, the taxonomy in the genus Centroceras was thrown into chaos worldwide. An analysis of what species was, or were, previously identified as C. clavulatum in Bermuda is the focus of the present molecular (COI-5P, rbcL) and morphological study. Two novel species are proposed, C. arcii sp. nov. and C. illaqueans sp. nov., and the distributions of three taxa recently segregated in the 'C. clavulatum complex' of the western Atlantic, C. gasparrinii, C. hyalacanthum, and C. micracanthum, have been expanded to include Bermuda. C. arcii is shown to be morphologically cryptic with C. micracanthum, and remains best distinguished by its COI-5P barcode sequence.

Current status, challenges and prospects for dairy goat production in the Americas

  • Lu, Christopher D.;Miller, Beth A.
    • Asian-Australasian Journal of Animal Sciences
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    • 제32권8_spc호
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    • pp.1244-1255
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    • 2019
  • Dairy goat production continues to be a socially, economically and culturally important part of the livestock industry in North, Central and South America and the Caribbean islands. Goat milk, cheese and other dairy products offer consumers food products with nutritional, health and environmental benefits. In North America, Mexico produces the greatest volume of goat milk, but most is for family or local consumption that is typical of a mixed farming system adopted by subsistence farmers in dry areas. The United States is not yet a large global goat milk producer, but the sector has expanded rapidly, with dairy goat numbers doubling between 1997 and 2012. The number of dairy goats has also increased dramatically in Canada. Commercial farms are increasingly important, driven by rising demand for good quality and locally sourced goat cheese. In South America, Brazil has the most developed dairy goat industry that includes government assistance to small-scale producers and low-income households. As of 2017, FAO identified Haiti, Peru, Jamaica, and Bolivia as having important goat milk production in the Western Hemisphere. For subsistence goat producers in the Americas on marginal land without prior history of chemical usage, organic dairy goat production can be a viable alternative for income generation, with sufficient transportation, sanitation and marketing initiatives. Production efficiency, greenhouse gas emission, waste disposal, and animal welfare are important challenges for dairy goat producers in the Americas.

Applied Computational Tools for Crop Genome Research

  • Love Christopher G;Batley Jacqueline;Edwards David
    • Journal of Plant Biotechnology
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    • 제5권4호
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    • pp.193-195
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    • 2003
  • A major goal of agricultural biotechnology is the discovery of genes or genetic loci which are associated with characteristics beneficial to crop production. This knowledge of genetic loci may then be applied to improve crop breeding. Agriculturally important genes may also benefit crop production through transgenic technologies. Recent years have seen an application of high throughput technologies to agricultural biotechnology leading to the production of large amounts of genomic data. The challenge today is the effective structuring of this data to permit researchers to search, filter and importantly, make robust associations within a wide variety of datasets. At the Plant Biotechnology Centre, Primary Industries Research Victoria in Melbourne, Australia, we have developed a series of tools and computational pipelines to assist in the processing and structuring of genomic data to aid its application to agricultural biotechnology resear-ch. These tools include a sequence database, ASTRA, for the processing and annotation of expressed sequence tag data. Tools have also been developed for the discovery of simple sequence repeat (SSR) and single nucleotide polymorphism (SNP) molecular markers from large sequence datasets. Application of these tools to Brassica research has assisted in the production of genetic and comparative physical maps as well as candidate gene discovery for a range of agronomically important traits.

Scalp Acupuncture and Master Tung Distal Points for the Treatment of Intraocular Pressure for a Patient with Borderline Glaucoma

  • Chapleau, Christopher
    • 식품보건융합연구
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    • 제4권2호
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    • pp.13-16
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    • 2018
  • Acupuncture has been clinically used to treat patients suffering from eye disease. It has been used in efforts to help preserve vision for those with a wide range of eye conditions including glaucoma and intraocular hypertension. High intraocular pressure (IOP) is usually associated with glaucoma and conventional treatment is focused on lowering IOP. Controlling this risk factor should help hasten the onset of glaucoma for those patents that are suspect or borderline candidates for glaucoma. In review of the limited scientific research there are not many studies that support conclusive evidence for the use of acupuncture on eye diseases and particularly glaucoma and ocular hypertension. For the information that does exist, diverse results from various interventions make it difficult to draw clear conclusions. The existing studies use different acupoints, techniques, frequencies, and durations. Individual treatment strategies according to the practitioner's subjective experience, patient condition, and the use of other complimentary and natural strategies is ideal for taking a more dynamic and wholistic approach to getting results. Until more pragmatic research models are funded and implemented, case reports can offer good examples of experiential and objective outcomes. This case report presents a 61 year old healthy female patient diagnosed with open-angle borderline glaucoma with elevated IOP. The patients IOP was successfully reduced with 12 treatments over three months using scalp electro-acupuncture and distal Master Tung points.

Evaluating the Information Access Skills of Students of a College of Education in Ghana

  • Yebowaah, Franklina Adjoa;Owusu-Ansah, Christopher M.
    • Journal of Information Science Theory and Practice
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    • 제8권2호
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    • pp.45-54
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    • 2020
  • Access to relevant information determines the quality of life of an individual in society and the academe. Academic institutions have established information literacy programmes to enhance students' access to information. With the elevation of colleges of education to tertiary status in Ghana, pre-service teachers are now required to conduct research to improve their reflective thinking in order to be certified. However, the information access skills of students in colleges of education in Ghana are uncertain. This study draws empirical evidence from students in the Nusrat Jahan Ahmadiyya College of Education, Wa, Ghana on their information access skills. Primary data were collected from 303 respondents from the college using a stratified sampling procedure. The data were collected using a questionnaire and analysed using descriptive statistics. The results indicate that information is available to students through different sources such as the Internet, libraries, and contact with friends and authorities. However, students were limited in respect to access to relevant online resources for their academic activities due to inadequate information access skills. Potential solutions are discussed.

Industry 4.0 - A challenge for variation simulation tools for mechanical assemblies

  • Boorla, Srinivasa M.;Bjarklev, Kristian;Eifler, Tobias;Howard, Thomas J.;McMahon, Christopher A.
    • Advances in Computational Design
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    • 제4권1호
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    • pp.43-52
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    • 2019
  • Variation Analysis (VA) is used to simulate final product variation, taking into consideration part manufacturing and assembly variations. In VA, all the manufacturing and assembly processes are defined at the product design stage. Process Capability Data Bases (PCDB) provide information about measured variation from previous products and processes and allow the designer to apply this to the new product. A new challenge to this traditional approach is posed by the Industry 4.0 (I4.0) revolution, where Smart Manufacturing (SM) is applied. The manufacturing intelligence and adaptability characteristics of SM make present PCDBs obsolete. Current tolerance analysis methods, which are made for discrete assembly products, are also challenged. This paper discusses the differences expected in future factories relevant to VA, and the approaches required to meet this challenge. Current processes are mapped using I4.0 philosophy and gaps are analysed for potential approaches for tolerance analysis tools. Matching points of simulation capability and I4.0 intents are identified as opportunities. Applying conditional variations, incorporating levels of adjustability, and the un-suitability of present Monte Carlo simulation due to changed mass production characteristics, are considered as major challenges. Opportunities including predicting residual stresses in the final product and linking them to product deterioration, calculating non-dimensional performances and extending simulations for process manufactured products, such as drugs, food products etc. are additional winning aspects for next generation VA tools.

A Dynamic Frequency Controlling Technique for Power Management in Existing Commercial Microcontrollers

  • Lueangvilai, Attakorn;Robertson, Christina;Martinez, Christopher J.
    • Journal of Computing Science and Engineering
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    • 제6권2호
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    • pp.79-88
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    • 2012
  • Power continues to be a driving force in central processing units (CPU) design. Most of the advanced breakthroughs in power have been in a realm that is applicable to workstation CPUs. Advanced power management systems will manage temperature, dynamic voltage scaling and dynamic frequency scaling in a CPU. The use of power management systems for microcontrollers and embedded CPUs has been modest, and mostly focuses on very large scale integration (VLSI) level optimizations compared to system level optimizations. In this paper, a dynamic frequency controlling (DFC) technique is introduced, to lay the foundation of a system level power management system for commercial microcontrollers. The DFC technique allows a commercial microcontroller to have minor modifications on both the hardware and software side, to allow the clock frequency to change to save power; results in this study show a 10% savings. By adding an additional layer of software abstraction at the interrupt level, the microcontroller can operate without having knowledge of the current clock frequency, and this can be accomplished without having to use an embedded operating system.

Comparative Analysis of Two Selective Bleaching Methods on Alpaca Fibers

  • Liu, Xin;Hurren, Christopher J.;Wang, Xungai
    • Fibers and Polymers
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    • 제4권3호
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    • pp.124-128
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    • 2003
  • Dark brown Alpaca fiber was reduced in shade via selective bleaching with peroxide. Two selective oxidative bleaching methods were tested on alpaca top to assess their effectiveness for color removal and fiber quality properties. Color change, bundle strength, weight loss, fiber diameter, surface modification, dye-ability and dye wash fastness were assessed for both methods and compared with the original brown top. Bleach method 1 (BL-I) showed little surface modification, 5.8% weight loss and 2.4% strength loss. D1925 yellowness index was reduced to 74.3 from 83.1 and provided a good base for the dyeing of medium to deep shades. Bleach method 2 (BL-II) displayed considerable surface modification, 7.8% weight loss and 18% strength loss. BL-II also resulted in a mean diameter reduction of 1.9 micron during bleaching. Yellowness was reduced to 64.5 from 83.1 and provided a very good base for the dyeing of medium to deep shades. BL-I showed better exhaustion of the premetallised dye Lanaset Violet B than BL-II. Wash fastness for BL-II was 1 grey scale unit poorer than BL-I. BL-II showed far better color clarity at pale depths however the wash fastness of the finished product was not good enough to maintain the depth or clarity of the color. BL-I showed poorer clarity of color but exhibited better wash fastness results.