Three-dimensional magnetic resonance (MR) images of four kinds of fruit (Japanese apricot, peach, Japanese pear, and apple) were acquired throughout their growing periods (from April to August) to visualize and quantify their vascular structures. The vascular structures were emphasized using T1-weighted spin-echo or gradient-echo pulse sequences, visualized using a maximum-intensity projection technique, and quantified using an image-segmentation program. As a result, we demonstrated that the vascular volume changed almost in proportion to the whole volume and that larger fruits generally had larger proportionality constants. We therefore concluded that MR microimaging is a powerful tool for studies of the vascular structure of fruit. 相似文献
This paper deals with the Keller–Segel system where Ω is a bounded domain in with smooth boundary , ; χ is a nonnegative function satisfying for some and . In the case that and , Fujie 2 established global existence of bounded solutions under the condition . On the other hand, when , Winkler 14 asserted global existence of bounded solutions for arbitrary . However, there is a gap in the proof. Recently, Fujie tried modifying the proof; nevertheless it also has a gap. It seems to be difficult to show global existence of bounded solutions for arbitrary . Moreover, the condition for K when cannot connect with the condition when . The purpose of the present paper is to obtain global existence and boundedness under more natural and proper condition for χ and to build a mathematical bridge between the cases and . 相似文献
We have designed a series of hydroxy(aryl)‐λ3‐iodane–[18]crown‐6 complexes, prepared from the corresponding iodosylbenzene derivatives and superacids in the presence of [18]crown‐6, and have investigated their reactivities in aqueous media. These activated iodosylbenzene monomers are all non‐hygroscopic shelf‐storable reagents, but they maintain high oxidizing ability in water. The complexes are effective for the oxidation of phenols, sulfides, olefins, silyl enol ethers, and alkyl(trifluoro)borates under mild conditions. Furthermore, hydroxy‐λ3‐iodane–[18]crown‐6 complexes serve as efficient progenitors for the synthesis of diaryl‐, vinyl‐, and alkynyl‐λ3‐iodanes in water. Other less polar organic solvents, such as methanol, acetonitrile, and dichloromethane, are also usable in some cases. 相似文献
We propose colors light detection and ranging (LiDAR) using visible laser diodes (LD) of red, green, and blue (RGB) colors to identify colors as well as obtain position information of surrounding objects. To verify the principle, we performed round-trip time-of-flight (TOF) measurements by irradiating a target of different colors with pulsed light from a LD of RGB colors. It is clarified that accurate distance measurements of up to 12 m can be realized in any RGB LD, and the received signal in each LD has different intensity characteristics depending on the target color. From a judgment table created from reception intensity characteristics for three types of LD and seven types of color target, the color of each target is successfully identified.
Assurance networks are designed to realize trustable Internet-Of-Things including terminal devices/infrastructure service applications for new generation networks. To construct assurance networks, it is necessary to evaluate them quantitatively. In this paper, we provide one of case studies to evaluate them quantitatively. In mobile ad hoc networks (MANETs), the network environments change over time due to the movement of nodes, the battery level of nodes, and so on. Assurance networks must maintain high performance even when such diverse changes of the network environments occur in the widely applicable domain. And if their performance degrades, they must early recover from the changes. So far, we have proposed a routing method for MANETs, called Route-Split Routing (RSR). RSR can suppress escalation of control packets in large scale MANETs. However, with RSR, drawbacks occur when some nodes exhaust their batteries. In this paper, we propose a sustainable route-split routing scheme to improve assurance by adapting node faults due to battery exhaustion for MANETs. To evaluate the assurance of the proposed method, we have implemented it with a simulator and have conducted simulation experiments. The results indicate that the proposed method can maintain high throughput when some nodes experience various levels of battery power and power consumption and even when some nodes die simultaneously. 相似文献