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41.
In the Tokyo metropolis many geological surveys are carried out in conjunction with building construction work and urban base improvement undertakings. Furthermore, the Institute of Civil Engineering (ICE) of the Tokyo Metropolitan Government (TMG) has been conducting surveys on urban geology, land subsidence, and geodetics. Thus, ICE of TMG keeps a lot of geological data. In order to plan for a more effective use of these data, the Geotechnical Data Information System of Tokyo Metropolitan Government was organized in 1985, and since 1986, it has become fully implemented.This Geotechnical Data Information System has incorporated a relational data base into a mainframe computer, the NEC ACOS System 430, and as of March 1989 it can retrieve and graphically present borehole, deep-well, and groundwater data.The authors wish to introduce in this article the organizational structure of the Geotechnical Data Information System of TMG, a summary of the data base system, standards of input data, and applicable examples of the data base. 相似文献
42.
Shotaro Nakayama Gerrit Blacquière Tomohide Ishiyama Satoshi Ishikawa 《Geophysical Prospecting》2019,67(6):1498-1521
The application of blended acquisition has drawn considerable attention owing to its ability to improve the operational efficiency as well as the data quality and health, safety and environment performance. Furthermore, the acquisition of less data contributes to the business aspect, while the desired data density is still realizable via subsequent data reconstruction. The use of fewer detectors and sources also minimizes operational risks in the field. Therefore, a combined implementation of these technologies potentially enhances the value of a seismic survey further. One way to encourage this is to minimize any imperfection in deblending and data reconstruction during processing. In addition, one may derive survey parameters that enable a further improvement in these processes as introduced in this study. The proposed survey design workflow iteratively performs the following steps to derive the survey parameters responsible for source blending as well as the spatial sampling of detectors and sources. The first step is the application of blending and sampling operators to unblended and well-sampled data. We then apply closed-loop deblending and data reconstruction. The residue for a given design from this step is evaluated and subsequently used by genetic algorithms to simultaneously update the survey parameters related to both blending and spatial sampling. The updated parameters are fed into the next iteration until they satisfy the given termination criteria. We also propose a repeated encoding sequence to form a parameter sequence in genetic algorithms, making the size of problem space manageable. The results of the proposed workflow are outlined using blended dispersed source array data incorporating different scenarios that represent acquisition in marine, transition zone and land environments. Clear differences attributed solely to the parameter design are easily recognizable. Additionally, a comparison among different optimization schemes illustrates the ability of genetic algorithms along with a repeated encoding sequence to find better solutions within a computationally affordable time. The optimized parameters yield a notable enhancement in the deblending and data reconstruction quality and consequently provide optimal acquisition scenarios. 相似文献
43.
Jun-Young Song Kei Nakayama Yasunori Murakami Sung-Ju Jung Myung-Joo Oh Satoru Matsuoka Hidemasa Kawakami Shin-Ichi Kitamura 《Marine pollution bulletin》2008,57(6-12):889
As basic research for the effect of heavy oil on the fish immune system, in this study, the number of leukocyte was counted in Japanese flounder Paralichthys olivaceus, after exposure to heavy oil at a concentration of 30 g/8 L for 3 days. To compare the numbers of bacteria in the skin mucus between oil-exposed and control fish, viable bacteria were enumerated by counting colony forming unit (CFU). Compared with 5.79 ± 1.88 × 107 leukocytes/mL in the controls, the exposed fish demonstrated higher counts, averaging 1.45 ± 0.45 × 108 cells/mL. The bacterial numbers of control fish were 4.27 ± 3.68 × 104 CFU/g, whereas they were 4.58 ± 1.63 × 105 CFU/g in the exposed fish. The results suggest that immune suppression of the fish occurred due to heavy oil stressor, and bacteria could invade in the mucus, resulting in the increasing leukocyte number to prevent infectious disease. 相似文献
44.
Ocean Science Journal - The genetic diversity and population structure of the fat greenling (Hexagrammos otakii) from the seven coastal locations in China, Korea, and Japan and the Okhotsk atka... 相似文献
45.
Irie K Kawaguchi M Mizuno K Song JY Nakayama K Kitamura S Murakami Y 《Marine pollution bulletin》2011,63(5-12):297-302
Heavy oil (HO) on the sea surface penetrates into fish eggs and prevents the normal morphogenesis. To identify the toxicological effects of HO in the context of the egg types, we performed exposure experiments using floating eggs and sinking eggs. In the course of development, HO-exposed embryos of floating eggs showed abnormal morphology, whereas early larva of the sinking eggs had almost normal morphology. However, the developing peripheral nervous system of sinking eggs showed abnormal projections. These findings suggest that HO exposed fishes have problems in the developing neurons, although they have no morphological malformations. Through these observations, we conclude that HO is strongly toxic to floating eggs in the morphogenesis, and also affect the neuron development in both floating and sinking eggs. 相似文献
46.
O. Noked A. Melchior R. Shuker S. Chizawa H. P. Liermann B. J. Kennedy M. Nakayama E. Sterer 《Physics and Chemistry of Minerals》2014,41(5):333-340
The high-pressure behavior of Li x La1/3NbO3 (x = 1/6, 1/3, 1/2, 2/3) perovskites where Li cations were substituted for the existing vacancies was studied using synchrotron X-ray diffraction. It was shown that all these materials undergo irreversible pressure-induced amorphization around 14.5 GPa regardless of the Li concentration. The Li-inserted materials were found to exhibit a standard pressure response (bulk modulus pressure derivative B 0′ ~4) when in the crystalline phase, whereas La1/3NbO3 shows a linear volume contraction versus pressure, i.e., B 0′ ~(?1). These results suggest that the structural collapse is not a consequence of cation disorder resulting from the Nb atoms (B-site) migrating to the A-site vacancies. The observed pressure response can be understood by increased occupancy of the A-sites opposing the tilting of the NbO6 octahedra. The pressure evolution of the Nb oxidation state is discussed. 相似文献
47.
A.?NakatsukaEmail author H.?Ueno N.?Nakayama T.?Mizota H.?Maekawa 《Physics and Chemistry of Minerals》2004,31(5):278-287
Synthesis experiments in the system MgAl2O4–MgFe2O4 [MgAl2–xFexO4 (0 x 2)] were carried out using a PbF2 flux. The crystalline products synthesized in the compositional range of 0.6 <x 1.2 consisted of two spinel phases, whereas those synthesized in the compositional ranges of 0.0 x 0.6 and 1.2 < x 2.0 crystallized as single spinel phases. Structure refinements of the spinel single crystals, which grew in the ranges of 0.0 x 0.6 and 1.2 < x 2.0, show that the degree of randomness of cation distribution between A and B sites increases as x approaches the two-phase region. This means that the degree of the size mismatch among Mg2+, Fe3+ and Al3+occupying each equivalent mixing site increases as x approaches the two-phase region. Consequently, if the coexistence of two spinels observed in the intermediate compositions reveals the existence of a miscibility gap at low temperatures, this increase in the degree of the size mismatch among the three cations is suggested as a factor of energetic destabilization to form the miscibility gap. 相似文献
48.
Iron, manganese and aluminum in upper waters of the western South Pacific Ocean and its adjacent seas 总被引:1,自引:0,他引:1
Hajime Obata Kiminori Shitashima Kenji Isshiki Eiichiro Nakayama 《Journal of Oceanography》2008,64(2):233-245
Total dissolvable iron, manganese and aluminum distributions in upper waters were determined in the western South Pacific,
Solomon Sea, Coral Sea, and Tasman Sea. In these oceanic regions, the surface aluminum distributions well reflect the atmospheric
deposition pattern of mineral dust in the western South Pacific reported previously. Surface manganese distributions derive
mainly from lateral transportation from the coastal sediments of western tropical islands. Compared to Mn and Al, the Fe distributions
reflect the nutrient cycle in upper waters. Iron limitation over the vast South Pacific, as revealed by physiological features
of phytoplankton, seems to be caused by low atmospheric dust deposition and low Fe:N ratios in deep waters. In the western
South Pacific, with its unique geographic and oceanographic settings, the local sources of trace metals might considerably
affect their biogeochemical cycles. 相似文献
49.
Toxicogenomic analysis of immune system-related genes in Japanese flounder (Paralichthys olivaceus) exposed to heavy oil 总被引:1,自引:1,他引:0
Kei Nakayama Shin-Ichi Kitamura Yasunori Murakami Jun-Young Song Sung-Ju Jung Myung-Joo Oh Hisato Iwata Shinsuke Tanabe 《Marine pollution bulletin》2008,57(6-12):445
Heavy oil contamination is one of the most important environmental issues. Toxicities of polycyclic aromatic hydrocarbons (PAHs), including immune toxicities, are well characterized, however, the immune toxic effects of heavy oil, as a complex mixture of PAHs, have not been investigated. In the present study, we selected Japanese flounder (Paralichthys olivaceus) as a model organism, and observed alteration of immune function by the exposure to heavy oil. To analyze the expression profiles of immune system-related genes, we selected 309 cDNAs from our flounder EST library, and spotted them on a glass slide. Using this cDNA array, alteration of gene expression profiles was analyzed in the kidneys of flounders exposed to heavy oil. Six Japanese flounders (mean body weight: 197 g) were acclimated to laboratory conditions at 19–20 °C. Three fish were exposed to heavy oil C (bunker C) at a concentration of 3.8 g/L for 3 days, and the others were kept in seawater without heavy oil and used as the control. After the exposure period, the fish were transferred into control seawater and maintained for 4 days, and then they were dissected and their kidneys were removed. Total RNA was extracted from the kidney samples to use in gene expression analyses. The microarray detected alteration of immune system-related genes in the kidneys of heavy oil-exposed flounders, including down-regulation of immunoglobulin light chain, CD45, major histocompatibility complex class II antigens and macrophage colony-stimulating factor precursor, and up-regulation of interleukin-8 and lysozyme. These results suggest that pathogen resistance may be weakened in heavy oil-exposed fish, causing a subsequent bacterial infection, and then proinflammatory genes may be induced as a defensive response against the infection. Additionally, we found candidate genes for use as biomarkers of heavy oil exposure, such as N-myc downstream regulated gene 1 and heat shock cognate 71 kDa proteins. 相似文献