246 research outputs found

    IMECE2002-33873 EMBEDDED ULTRASONIC STRUCTURAL RADAR WITH PIEZOELECTRIC WAFER ACTIVE SENSORS FOR THE NDE OF THIN-WALL STRUCTURES

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    ABSTRACT Embedded-ultrasonics structural radar (EUSR) is a new concept and methodology for in-situ nondestructive evaluation (NDE) and structural health monitoring (SHM) of thin-wall structures. EUSR consists (a) an array of piezoelectric wafer active sensors (PWAS) embedded into the structure; and (b) electronic modules for signal transmission/reception, processing, and interpretation. EUSR utilizes guided elastic waves (Lamb waves) generated omnidirectionally into the thin-wall structure by surface-mounted permanently-attached PWAS. The paper starts with the general concepts of the EUSR algorithm: transmission beamforming, reception beamforming, and time of fight determination. Next, details of the Lamb wave generation with PWAS, verification of group-velocity dispersion curves, identification of optimal excitation frequency, and confirmation of wave front omnidirectionality are discussed. In the third part of the paper, the actual implementation of the EUSR method in a proof-of-concept demonstration is presented. The construction of the PWAS phased array is described, and detection of cracks located broadside and offside of the PWAS array is illustrated. The method is shown to be easy to use through a visually interactive LabView TM interface. Very good detection accuracy is observed. Though the proof-of-concept experiments presented in this paper were illustrated on metallic structures, the EUSR concept works just as well on composite and hybrid structures

    Anti-inflammatory effects, nuclear magnetic resonance identification, and high-performance liquid chromatography isolation of the total flavonoids from Artemisia frigida

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    AbstractThe aerial parts of Artemisia frigida Willd. are used to treat joint swelling, renal heat, abnormal menstruation, and sore carbuncle. The anti-inflammatory effects of A. frigida have been well-known in folk medicine, suggesting that components extracted from A. frigida could potentially treat inflammatory disease. With the aim of discovering bioactive compounds, in this study, we extracted total flavonoids from the aerial parts of A. frigida and investigated their anti-inflammatory effects against inflammation induced by carrageenan and egg albumin in rats. At the doses studied, total flavonoids (100 mg/kg, 200 mg/kg, and 400 mg/kg) and some isolated compounds (30 mg/kg) showed significant and dose-dependent anti-inflammatory effects. According to the high-performance liquid chromatography analysis of the total flavonoids from A. frigida, there are five major compounds, namely, 5-hydroxy-3′,4′-dimethoxy-7-O-β-d-glucuronide (F1), 5-hydroxy-3′,4′,5′-trimethoxy-7-O-β-d-glucuronide (F2), 5,7,3′-trihydroxy-6,4′-dimethoxyflavone (F3), 5,3′-dihydroxy-6,7,4′-trimethoxyflavone (F4), and 5,3′-dihydroxy-3,6,7,4′-tetramethoxyflavone (F5), which may explain the anti-inflammatory activity

    Fusion primer and nested integrated PCR (FPNI-PCR): a new high-efficiency strategy for rapid chromosome walking or flanking sequence cloning

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    <p>Abstract</p> <p>Background</p> <p>The advent of genomics-based technologies has revolutionized many fields of biological enquiry. However, chromosome walking or flanking sequence cloning is still a necessary and important procedure to determining gene structure. Such methods are used to identify T-DNA insertion sites and so are especially relevant for organisms where large T-DNA insertion libraries have been created, such as rice and <it>Arabidopsis</it>. The currently available methods for flanking sequence cloning, including the popular <it>TAIL-PCR </it>technique, are relatively laborious and slow.</p> <p>Results</p> <p>Here, we report a simple and effective fusion primer and nested integrated PCR method (<it>FPNI-PCR</it>) for the identification and cloning of unknown genomic regions flanked known sequences. In brief, a set of universal primers was designed that consisted of various 15-16 base arbitrary degenerate oligonucleotides. These arbitrary degenerate primers were fused to the 3' end of an adaptor oligonucleotide which provided a known sequence without degenerate nucleotides, thereby forming the fusion primers (FPs). These fusion primers are employed in the first step of an integrated nested PCR strategy which defines the overall <it>FPNI-PCR </it>protocol. In order to demonstrate the efficacy of this novel strategy, we have successfully used it to isolate multiple genomic sequences namely, 21 orthologs of genes in various species of Rosaceace, 4 <it>MYB </it>genes of Rosa rugosa, 3 promoters of transcription factors of Petunia hybrida, and 4 flanking sequences of T-DNA insertion sites in transgenic tobacco lines and 6 specific genes from sequenced genome of rice and <it>Arabidopsis</it>.</p> <p>Conclusions</p> <p>The successful amplification of target products through <it>FPNI-PCR </it>verified that this novel strategy is an effective, low cost and simple procedure. Furthermore, <it>FPNI-PCR </it>represents a more sensitive, rapid and accurate technique than the established <it>TAIL-PCR </it>and <it>hiTAIL-PCR </it>procedures.</p

    Effective exploitation potential of shale gas from lower cambrian niutitang formation, Northwestern Hunan, China

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    The marine shale in the Lower Cambrian Niutitang Formation is the dominant shale-gas reservoir in northwestern Hunan, which accounts for more than 70% of unconventional energy in Hunan province. Accurately evaluating the shale-gas exploitation potential is a key to determining whether commercial exploitation standards can be met. In the literature, most existing studies have focused on evaluating the shale-gas exploitation potential based on either accumulation conditions or the shale fracability, which will lead to a gap between the real production and proven gas reserves due to the characteristics of the shale’s low permeability and low porosity. Therefore, further studies are needed to evaluate the effective shale-gas exploitation potential. To address this need, the outcrop shale samples in the Niutitang Formation were collected from the target regions, and the geological characteristics, mechanics behavior, and microstructure performance were discussed via both field data and laboratory tests. The results revealed that the shale-gas exploitation potential in the Niutitang Formation was indicated to be comparable to that of five validated shale-gas exploitation regions in the United States. To further illustrate the effective shale-gas exploitation potential, this study suggested using a comprehensive evaluation framework for this purpose, in which both accumulation condition and the shale fracability are simultaneously considered. Therefore, the shale gas reservoir in the Niutitang Formation has highly effective shale-gas exploitation potential by considering both the accumulation conditions and the shale fracability

    Apresiasi Masyarakat Terhadap Tradisi Lisan Permainan Rakyat Jaran Kepang Di Kanagarian Simalidu Kecamatan Koto Salak Kabupaten Dharmasraya

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    The perposes of this researeh are to describe and the explain the appreciation of society in kanagarian Simalidu Kecamatan Koto Salak Kabupaten Dharmasraya. West Sumatra to the Jaran Kepang. The research is using the descriptive methade and the of this research is qualitative the issues that describe is type the appreciation and the acceptance of the society to Jaran Kepang in Kanagarian Simalidu Kecamatan Koto Salak Kabupaten Dharmasraya. That obtainable through the questionnaire and interview that using by the instrument in this research. The accumulation technique of data that using here are: (1) the observation to searching the informan that requires in the research, (2) give the questionnaire that contain same questions that have to be answered by the society in Kanagarian Simalidu Kecamatan Koto Salak Kabupaten Dharmasraya, (3) The structural interview, by using some questions to the informans based an the research, (4) record, by recorded oral data that express by the informans, (5) note, by kating all the informan that has bean obtained from the observation the interview, and the recard

    Balancing Logit Variation for Long-tailed Semantic Segmentation

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    Semantic segmentation usually suffers from a long-tail data distribution. Due to the imbalanced number of samples across categories, the features of those tail classes may get squeezed into a narrow area in the feature space. Towards a balanced feature distribution, we introduce category-wise variation into the network predictions in the training phase such that an instance is no longer projected to a feature point, but a small region instead. Such a perturbation is highly dependent on the category scale, which appears as assigning smaller variation to head classes and larger variation to tail classes. In this way, we manage to close the gap between the feature areas of different categories, resulting in a more balanced representation. It is noteworthy that the introduced variation is discarded at the inference stage to facilitate a confident prediction. Although with an embarrassingly simple implementation, our method manifests itself in strong generalizability to various datasets and task settings. Extensive experiments suggest that our plug-in design lends itself well to a range of state-of-the-art approaches and boosts the performance on top of them

    MIAD: A Maintenance Inspection Dataset for Unsupervised Anomaly Detection

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    Visual anomaly detection plays a crucial role in not only manufacturing inspection to find defects of products during manufacturing processes, but also maintenance inspection to keep equipment in optimum working condition particularly outdoors. Due to the scarcity of the defective samples, unsupervised anomaly detection has attracted great attention in recent years. However, existing datasets for unsupervised anomaly detection are biased towards manufacturing inspection, not considering maintenance inspection which is usually conducted under outdoor uncontrolled environment such as varying camera viewpoints, messy background and degradation of object surface after long-term working. We focus on outdoor maintenance inspection and contribute a comprehensive Maintenance Inspection Anomaly Detection (MIAD) dataset which contains more than 100K high-resolution color images in various outdoor industrial scenarios. This dataset is generated by a 3D graphics software and covers both surface and logical anomalies with pixel-precise ground truth. Extensive evaluations of representative algorithms for unsupervised anomaly detection are conducted, and we expect MIAD and corresponding experimental results can inspire research community in outdoor unsupervised anomaly detection tasks. Worthwhile and related future work can be spawned from our new dataset

    Whole-genome resequencing reveals genetic diversity and selection characteristics of dairy goat

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    The dairy goat is one of the earliest dairy livestock species, which plays an important role in the economic development, especially for developing countries. With the development of agricultural civilization, dairy goats have been widely distributed across the world. However, few studies have been conducted on the specific characteristics of dairy goat. In this study, we collected the whole-genome data of 89 goat individuals by sequencing 48 goats and employing 41 publicly available goats, including five dairy goat breeds (Saanen, Nubian, Alpine, Toggenburg, and Guanzhong dairy goat; n = 24, 15, 11, 6, 6), and three goat breeds (Guishan goat, Longlin goat, Yunshang Black goat; n = 6, 15, 6). Through compared the genomes of dairy goat and non-dairy goat to analyze genetic diversity and selection characteristics of dairy goat. The results show that the eight goats could be divided into three subgroups of European, African, and Chinese indigenous goat populations, and we also found that Australian Nubian, Toggenburg, and Australian Alpine had the highest linkage disequilibrium, the lowest level of nucleotide diversity, and a higher inbreeding coefficient, indicating that they were strongly artificially selected. In addition, we identified several candidate genes related to the specificity of dairy goat, particularly genes associated with milk production traits (GHR, DGAT2, ELF5, GLYCAM1, ACSBG2, ACSS2), reproduction traits (TSHR, TSHB, PTGS2, ESR2), immunity traits (JAK1, POU2F2, LRRC66). Our results provide not only insights into the evolutionary history and breed characteristics of dairy goat, but also valuable information for the implementation and improvement of dairy goat cross breeding program
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