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101.
We consider the following network design problem; Given a vertex set V with a metric cost c on V, an integer k≥1, and a degree specification b, find a minimum cost k-edge-connected multigraph on V under the constraint that the degree of each vertex v∈V is equal to b(v). This problem generalizes metric TSP. In this paper, we show that the problem admits a ρ-approximation algorithm if b(v)≥2, v∈V, where ρ=2.5 if k is even, and ρ=2.5+1.5/k if k is odd. We also prove that the digraph version of this problem admits a 2.5-approximation algorithm and discuss some generalization
of metric TSP. 相似文献
102.
This article proposes a function for color information detection using genetic programming (GP). In image-processing, object
detection is one of the important processes. In cases where the object has a complex color domain, detection becomes more
difficult. We generated a detection function for a complex color domain by using GP. The detection function deals with one
pixel of an input image, and it obtains an output image by processing for all pixels. We aimed at a reduction in the time
taken by a human to consider an image-processing system design. We applied the generation of GP to detect a target color region
in actual images. The results show that the detection function has sufficient ability for these detections. 相似文献
103.
Lydie du Bousquet Masahide Nakamura Ben Yan Hiroshi Igaki 《Innovations in Systems and Software Engineering》2009,5(3):181-196
A home network system consists of multiple networked appliances, intended to provide more convenient and comfortable living
for home users. Before being deployed, one has to guarantee the correctness, the safety, and the security of the system. Here,
we present the approach chosen to validate the Java implementation of a home network system. We rely on the Java Modelling
Language to formally specify and validate an abstraction of the system.
This is a substantially revised version of our paper that appeared in the proceedings of the Workshop On Leveraging Applications
of Formal Methods, Verification and Validation (ISoLA), Poitiers-Futuroscope, France, December 2007. 相似文献
104.
A novel method for three-dimensional observation of the vascular networks in the whole mouse brain 总被引:1,自引:0,他引:1
A novel method for acquiring serial images suitable for three-dimensional reconstruction of vascular networks in the whole brain of mouse was developed. The brain infused with a White India ink-gelatin solution was fixed and embedded in paraffin containing Sudan Black B through xylene also containing Sudan Black B. Each sliced surface of the paraffin block was coated with liquid paraffin and its image was serially acquired. Coating with liquid paraffin extremely improved the quality of the image. The series of serial images was free of distortion and a three-dimensional image was reconstructed without the problem of the alignment and registration of adjacent images. The volume-rendered image indicated three-dimensional distribution of blood vessels in a whole brain. No ghost or shadow was observed on a volume-rendered image of the White India ink-gelatin infused brain. The z-axial resolution examined on the orthogonal sections reconstituted from serial images obtained at an interval of 5 mum showed no cross talk, indicating that the z-axial resolution was no larger than 5 mum. A proper understanding of the vascular system in a whole brain is indispensable to reveal the development of the vascular system in the brain of normal and genetically manipulated mouse and vascular alterations in pathological situation, such as stroke and neurodegenerative disease. Although simple and inexpensive, this method will provide fundamental information on the vascular system in a whole brain. 相似文献
105.
Kojima Masami Tasaki Takafumi Suzuki Yukihisa Kamijo Toshio Hada Aki Kik Alfred Ikehata Masateru Sasaki Hiroshi 《Journal of Infrared, Millimeter and Terahertz Waves》2022,43(3-4):260-271
Journal of Infrared, Millimeter, and Terahertz Waves - Millimeter waves (MMW) absorbed by skin or cornea may induce damage by heat. We have developed a 60 GHz MMW exposure-induced eye... 相似文献
106.
107.
108.
The effect of small dose of topiroxostat on serum uric acid in patients receiving hemodialysis 下载免费PDF全文
Yume Nagaoka Yoshiko Tanaka Hiroshi Yoshimoto Rie Suzuki Kakei Ryu Mio Ueda Minako Akiyama Miho Nagai Yoshitaka Miyaoka Eiichiro Kanda Shinnichi Iwai Michio Nagaoka Yoshihiko Kanno 《Hemodialysis international. International Symposium on Home Hemodialysis》2018,22(3):388-393
Introduction : Topiroxostat, a recently developed xanthine oxidase inhibitor, is expected to have fewer adverse effects than allopurinol because it has different mechanism of action from alloprinol. However, its dosage, usage and safety have not been established in patients with impaired renal function or those undergoing dialysis at the development since no studies was conducted in these patients. Methods : Cross over clinical trial using 3 months of allopurinol and topiroxostat on 27 maintain Japanese HD patients were carried out. The effects on oxidative stress status of both drugs were also evaluated by measuring oxidation reduction potential. Findings : Twenty‐five of twenty‐seven patients completed study. The mean serum uric acid levels in the topiroxostat‐treated arm was significantly lower than it in the allopurinol‐treated arm time‐dependently (P < 0.0001). Corrected oxidative stress ratio defined as biological antioxidant potential/diacron reactive oxygen metabolites was significantly increased in topiroxostat‐arm (*P = 0.0035), but not in allopurinol‐arm (P = 0.1429). No significant difference was seen in diacron reactive oxygen metabolites, biological antioxidant potential, static oxidation‐reduction potential, and capacity oxidation‐reduction potential between pre and post treatment of both drugs. Discussion : It is suggested that a low dose of topiroxostat decreased serum uric acid sufficiently to maintain it below 7.0 mg/dL in patients receiving hemodialysis. 相似文献
109.
T Matsunaga F Hirayama Y Yonemura R Murray M Ogawa 《Canadian Metallurgical Quarterly》1998,92(3):901-907
The receptors for interleukin-3 (IL-3), granulocyte-macrophage colony-stimulating factor (GM-CSF), and IL-5 share a common signaling subunit betac. However, in the mouse, there is an additional IL-3 signaling protein, betaIL-3, which is specific for IL-3. We have previously reported that IL-3 abrogates the lymphoid potentials of murine lymphohematopoietic progenitors and the reconstituting ability of hematopoietic stem cells. We used bone marrow cells from betac- and betaIL-3-knock-out mice to examine the relative contributions of the receptor proteins to the negative regulation by IL-3. First, we tested the effects of IL-3 on lymphohematopoietic progenitors by using lineage-negative (Lin-) marrow cells of 5-fluorouracil (5-FU)-treated mice in the two-step methylcellulose culture we reported previously. Addition of IL-3 to the combination of steel factor (SF, c-kit ligand) and IL-11 abrogated the B-lymphoid potential of the marrow cells of both types of knock-out mice as well as wild-type mice. Next, we investigated the effects of IL-3 on in vitro expansion of the hematopoietic stem cells. We cultured Lin-Sca-1-positive, c-kit-positive marrow cells from 5-FU-treated mice in suspension in the presence of SF and IL-11 with or without IL-3 for 7 days and tested the reconstituting ability of the cultured cells by transplanting the cells into lethally irradiated Ly-5 congenic mice together with "compromised" marrow cells. Presence of IL-3 in culture abrogated the reconstituting ability of the cells from both types of knock-out mice and the wild-type mice. In contrast, addition of GM-CSF to the suspension culture abrogated neither B-cell potential nor reconstituting abilities of the cultured cells of wild-type mice. These observations may have implications in the choice of cytokines for use in in vitro expansion of human hematopoietic stem cells and progenitors. 相似文献
110.
Hiroshi Kametani 《Metallurgical and Materials Transactions B》1998,29(6):1261-1267
Data concerning the length of longitudinal cracks on the surface of continuously cast steel slabs were collected from two
plants. The data were analyzed to find the relation between crack length and crack frequency. The analysis revealed the following.
相似文献
(1) |
After normalization to eliminate the effect of different casting conditions, the fractal relation characterizing the normalized
cumulative frequency distribution (N (m−2)) and the crack length (L (mm)) of the primary surface cracks could be represented by the equation |
|
(2) | The values for γ varied over a wide range, but remained constant throughout a heat and were the same for both the upper and lower faces of the slab. | |
(3) | It was found that in some instances, when L exceeded a critical value (L c), the value of L became δ times longer than the length predicted by the previous distribution. This increase in L was ascribed to secondary growth of the cracks. This occurred more frequently on the lower, rather than on the upper, face of the slab. The product of L c and δ was approximately constant. The formation of the surface cracks is discussed in view of the fractal phenomena. |