Hydraulic Properties of Froth Layer on a Perforated Plate

This paper deals with the comparison of gas-liquid holdup and froth height on a perforated plate under various operational conditions such as liquid stagnant, cocurrent, countercurrent and crosscurrent gas-liquid flow system. Tendency to foam is remarkable in countercurrent and crosscurrent flow system. The crosscurrent flow system is suitable for the operation of mass transfer from the point of view of gas-liquid holdup

Size of Bubbles and Gas Holdup in Bubble Columns

Bubble columns are extensively used in the chemical industry. This paper evaluates the present state of the art on the size of bubbles from a sieve plate and gas holdup, mainly on the basis of the results of the authors, including previous ones. The size of bubbles formed from a sieve plate has an insignificant effect of chamber volume, and gas holdup shows some different behavior, depending on the hole diameter to liquid depth

<Preliminary>Thermal Softening of Wet Wood in the Temperature Range of 0 to 200℃

この論文は国立情報学研究所の学術雑誌公開支援事業により電子化されました

Development of a magnetically suspended, tetrahedron-shaped antenna pointing system

A magnetically suspended, tetrahedron-shaped antenna pointing system is proposed for use in a multibeam broadcasting satellite system in the future. The structure of this system is presented, along with its design concept and the functional test results which were obtained in a laser tracking system in the laboratory. According to these results, it has been confirmed that the system has many advantages over conventional systems and excellent performance

An optical system for measuring the eccentricity of glass wool pipe－for industrial use

An optical system for measuring the eccentricity of the glass wool pipe has been developed for an industrial use. The system consists of a contact sensor, a photo light sensor and a signal processing system with a logic circuit. The system is simple, fast and efficient for practical use; it allows implementation of on-line process monitoring and alarm warning signals for unacceptable pipe eccentricity during manufacturing

A flexibly shaped space-time scan statistic for disease outbreak detection and monitoring

<p>Abstract</p> <p>Background</p> <p>Early detection of disease outbreaks enables public health officials to implement disease control and prevention measures at the earliest possible time. A time periodic geographical disease surveillance system based on a cylindrical space-time scan statistic has been used extensively for disease surveillance along with the SaTScan software. In the purely spatial setting, many different methods have been proposed to detect spatial disease clusters. In particular, some spatial scan statistics are aimed at detecting irregularly shaped clusters which may not be detected by the circular spatial scan statistic.</p> <p>Results</p> <p>Based on the <it>flexible purely spatial scan statistic</it>, we propose a flexibly shaped space-time scan statistic for early detection of disease outbreaks. The performance of the proposed space-time scan statistic is compared with that of the cylindrical scan statistic using benchmark data. In order to compare their performances, we have developed a space-time power distribution by extending the purely spatial bivariate power distribution. Daily syndromic surveillance data in Massachusetts, USA, are used to illustrate the proposed test statistic.</p> <p>Conclusion</p> <p>The flexible space-time scan statistic is well suited for detecting and monitoring disease outbreaks in irregularly shaped areas.</p

The Spatial Signature of Biotic Interactions of a Clonal and a Non-clonal Palmetto in a Subtropical Plant Community

Spatial analyses of plant-distribution patterns can provide inferences about intra- and interspecific biotic interactions. Yet, such analyses are rare for clonal plants because effective tools (i.e., molecular markers) needed to map naturally occurring clonal individuals have only become available recently. Clonal plants are unique in that a single genotype has a potential to spatially place new individuals (i.e., ramets) in response to intra- and interspecific biotic interactions. Laboratory and greenhouse studies suggest that some clonal plants can avoid intra-genet, inter-genet, and inter-specific competition via rootplacement patterns. An intriguing and yet to be explored question is whether a spatial signature of such multi-level biotic interactions can be detected in natural plant communities. The facultatively clonal Serenoa repens and non-clonal Sabal etonia are ecologically similar and co-dominant palmettos that sympatrically occur in the Florida peninsula. We used amplified fragment length polymorphisms (AFLPs) to identify Serenoa genets and also to assign field-unidentifiable small individuals as Sabal seedlings, Serenoa seedlings, or Serenoa vegetative sprouts. Then, we conducted univariate and bivariate multi-distance spatial analyses to examine the spatial interactions of Serenoa (n=271) and Sabal (n=137) within a 20x20 m grid at three levels, intragenet, intergenet and interspecific. We found that spatial interactions were not random at all three levels of biotic interactions. Serenoa genets appear to spatially avoid self-competition as well as intergenet competition. Furthermore, Serenoa and Sabal were spatially negatively associated with each other. However, this negative association pattern was also evident in a spatial comparison between non-clonal Serenoa and Sabal, suggesting that Serenoa genets’ spatial avoidance of Sabal through placement of new ramets is not the explanation of the interspecific-level negative spatial pattern. Our results emphasize the importance of investigating spatial signatures of biotic as well as abiotic interactions at multiple levels in understanding spatial distribution patterns of clonal plants in natural plant communities