Multimedia and Internet Business Clusters in Central Tokyo     

《Urban geography》2013,34(5):483-500

This paper discusses the concentration of multimedia and Internet businesses in Central Tokyo. The multimedia businesses producing various digitized materials and the other businesses related to the Internet can be identified as a business domain referred to as "the multimedia and Internet industry." Tokyo is the location of the largest concentration of multimedia and Internet businesses in Japan. Several industrial clusters of such businesses can be identified in Central Tokyo through the locational analysis of the firms utilizing GIS techniques. Among these clusters, Kanda, the largest one with its tradition of IT related technical and publishing/printing businesses, contains a number of software design and application service firms. In contrast, Shibuya, the second largest cluster without any pre-existing industrial tradition, specializes in multimedia and Web content business. Shibuya, which is popularly called "Bit Valley," has grown rapidly correspondence with the expansion of the demand for multimedia and Web content products on the bases of its denser industrial relations compared to those in the other clusters and of few disadvantages in the competition for human resources for creative workers employment due to a distinct local labor market.  相似文献   

基于流固耦合统一计算框架的三维大规模海域场地地震反应分析?以东京湾为例     

黄朝龙  陈少林  沈吉荣  张丽芳 《震灾防御技术》2022,17(3):420-430

海域场地地震响应分析是确定海洋工程结构抗震设计地震动输入的重要环节。然而,针对海水、饱和土、基岩之间的流固耦合分析,目前一般通过对3种介质方程进行离散,然后整体求解或分区耦合求解的方式进行,过程复杂而低效。因此,大规模海域场地地震反应分析仍是一个挑战性问题。本文基于流固耦合统一计算框架求解海域近场波动问题,采用透射边界模拟无限域,通过将海水和基岩视为孔隙率分别等于1和0的广义饱和多孔介质,使得海水、饱和土、基岩之间的相互耦合可在统一计算框架中实现,避免不同介质求解器之间的数据交换。采用集中质量显式有限元并行计算,不同进程之间采用MPI进行数据交换,提高计算效率;采用逐元技术,按单元类别存储单元刚度,大大节省了内存,便于大规模计算。通过自编程,输入界面高程数据和材料参数,实现建模-自由场-三维地震动模拟全流程自动化。以东京湾为例,使用该方法和程序在超级计算机上模拟SV波垂直入射时的地震响应,证实了该方法用于三维大规模海域地震波场模拟的高效性和可行性。  相似文献   

日本东京"多中心"城市发展模式的形成、特点与趋势   总被引：6，自引：0，他引：6  

虞震 《地域研究与开发》2007,26(5):75-78

首先详细回顾并分析了日本东京"多中心"城市发展模式的演变过程,指出东京"多中心"模式的形成原因,主要是为了减少对中心城区基础设施的压力,并且通过在中心城区之外创造新的就业中心来缩短通勤距离.其次探讨并归纳了该模式的形成背景与特点,认为东京"多中心"模式是以发达的公共大交通为基础,城市副中心既是市民的集中居住地,又是特定产业和技术创新的集聚区,同时还是分散首都功能的大都市功能区.最后指出东京城市发展的未来趋势是要形成多功能、集约型的都市构造.  相似文献   

Environmental controls on phytoplankton production in coastal ecosystems: A case study from Tokyo Bay     

Heather A. Bouman  Toru Nakane  Kenji Oka  Kisaburo Nakata  Kiyo Kurita  Shubha Sathyendranath  Trevor Platt 《Estuarine, Coastal and Shelf Science》2010

Phytoplankton biomass and primary production were examined in their environmental context, for a semi-enclosed bay (Tokyo Bay, Japan) using data from monthly samples collected over a three-year period. Heavy precipitation and high surface temperatures in the late spring and summer gave rise to a highly-stratified water-column and stimulated a series of phytoplankton blooms, whereas during the winter, a weakly-stratified and deeply-mixed water-column led to a rapid decline in phytoplankton biomass under light-limited growth conditions. By incorporating pigment, photophysiological and optical data into a primary production model we show that daily, water-column primary production ranges from ∼160 mg C m⁻² d⁻¹ to 7600 mg C m⁻² d⁻¹. High water turbidity and deep vertical mixing, both separately and in concert, limit the light available for algal growth over much of the year. Annual primary production varied from 370 to 580 g C m⁻² y⁻¹. The relative influences of nutrient limitation and light limitation are assessed. A model is developed that describes this in an explicit manner using photophysiological parameters.  相似文献   

Seasonal Variations in Abundance and Size Composition of the Lobate Ctenophore Bolinopsis Mikado (Moser) in Tokyo Bay, Central Japan   总被引：1，自引：0，他引：1  

Tomoyuki Kasuya  Takashi Ishimaru  Masaaki Murano 《Journal of Oceanography》2000,56(4):419-427

Surveys of the abundance and size composition of the ctenophore Bolinopsis mikado were conducted in Tokyo Bay over a 5-year period from 1990 to 1994. B. mikado appeared throughout the year, and its mass occurrence was observed between August and November; annual maximum abundance ranged from 19 to 91 ind. m^–2. Water temperature seems to influence the seasonal variation of B. mikado abundance. Environmental conditions (e.g. rough waters due to a typhoon) and predation by the beroid ctenophore Beroe cucumis appear to affect annual variations of B. mikado abundance. Size frequency distributions of B. mikado indicated that its reproduction was most active in summer and fall but occurred throughout the year in Tokyo Bay. A sharp decline of the copepod population in August 1990 was probably due to predation by B. mikado which was very abundant at that time; its predatory impact was estimated to be 24 % day^–1.  相似文献   

A real-time observation network of ocean-bottom-seismometers deployed at the Sagami trough subduction zone,central Japan     

Eguchi  Takao  Fujinawa  Yukio  Fujita  Eisuke  Iwasaki  Sin-Iti  Watabe  Isao  Fujiwara  Hiroyuki 《Marine Geophysical Researches》1998,20(2):73-94

We installed a real-time operating regional observation network of Ocean-Bottom-Seismometers, connected to an electro-optical fiber communication cable, at the Sagami trough subduction zone, just south of the Tokyo metropolitan area, central Japan. The network, called ETMC, has six seismic observation sites at approximately 20 km spacing. In addition, there are three tsunami observation sites along the ETMC network to monitor the propagation process of tsunamis around the Sagami trough region.The on-line data from the ETMC has been improving the detection capability of smaller-magnitude earthquakes even at areas close to the margin of the trough. The ETMC data analyzing system, which has a function of real-time digital filtering for each seismic channel, can read the arrival times of P- and S-waves precisely, constraining well the automatic on-line hypocenter locations. The network has been providing useful information regarding the bending and downgoing process of the Philippine sea plate at the Sagami trough subduction zone.The pressure sensors of the installed network have a detection capability of tsunami wave trains with an amplitude of less than 1 cm. For example, the sensors recorded the full time history of tsunami wave trains, with mm order resolution, originating from a tsunami earthquake with 5.7 M_W and the tsunami magnitude of 7.5 occurred near Tori Shima (Tori Is.) of the Izu-Bonin Is. arc on September 4, 1996. The maximum amplitude of the tsunami signals on the trough-floor was approximately 1 cm (P-P), in contrast with approximately 20 cm (0-P) at a coastal site on Izu-Oshima, near the trough. Also, the pressure sensors observed tsunamis due to a large tsunami earthquake (7.1 M_W) at the northern New Guinea, on July 17, 1998.  相似文献   

A coastal acoustic tomography experiment in the Tokyo Bay   总被引：1，自引：0，他引：1  

KANEKO Arat  YAMAGUCHI Keisuke  YAMAMOTO Tokuo  GOHDA Noriaki  ZHENG Hong  SYAMSUDIN Fadli  LIN Ju  NGUYEN Hong-Quang  MATSUYAMA Masaji  HACHIYA Hiroyuki  HASHIMOTO Noriaki 《海洋学报(英文版)》2005,24(1):86-94

Eight sets of coastal acoustic tomography (CAT) systems were deployed during November 29 to December 10, 2002 at the coasts on both sides of Tokyo Bay to measure tidal current structures at 15-rain interval.Sound transmission across the Tokyo Bay (between Yokohama and Chiba)was successfillly traced,even under severe interference from ship generated wakes and bubbles.Tidal current fields changing from northward to southward flow are well reconstructed by the inverse analysis of travel-time difference data for a period with the best sound transmission condition. It is suggested that the CAT is the most powerful tool to continuously map tidal current fields in the coastal seas with heavy shipping traffic and fisheries activity.  相似文献   

Changing gender differences in commuting in the Tokyo metropolitan suburbs     

Masaki Kawase 《GeoJournal》2004,61(3):247-253

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Nine requirements for the origin of Earth's life:Not at the hydrothermal vent,but in a nuclear geyser system     

Shigenori Maruyama  Ken Kurokawa  Toshikazu Ebisuzaki  Yusuke Sawaki  Konomi Suda  M.Santo 《地学前缘(英文版)》2019,10(4):1337-1357

The origin of life on Earth remains enigmatic with diverse models and debates.Here we discuss essential requirements for the first emergence of life on our planet and propose the following nine requirements:(1)an energy source(ionizing radiation and thermal energy);(2)a supply of nutrients(P.K.REE.etc.);(3)a supply of life-constituting major elements;(4)a high concentration of reduced gases such as CH_4,HCN and NH_3;(5)dry-wet cycles to create membranes and polymerize RNA;(6)a non-toxic aqueous environment;(7)Na-poor water;(8)highly diversified environments,and(9)cyclic conditions,such as dayto-night,hot-to-cold etc.Based on these nine requirements,we evaluate previously proposed locations for the origin of Earth's life,including:(1)Darwin's "warm little pond",leading to a "prebiotic soup" for life;(2)panspermia or Neo-panspermia(succession model of panspermia);(3)transportation from/through Mars;(4)a deepsea hydrothermal system;(5)an on-land subduct ion-zone hot spring,and(6)a geyser systems driven by a natural nuclear reactor.We conclude that location(6)is the most ideal candidate for the o rigin point for Earth's life because of its efficiency in continuously supplying both the energy and the necessary materials for life,thereby maintaining the essential "cradle" for its initial development.We also emphasize that falsifiable working hypothesis provides an important tool to evaluate one of the biggest mysteries of the universe-the origin of life.  相似文献   

东京动漫产业空间集聚与企业区位选择研究   总被引：2，自引：0，他引：2  

褚劲风 《地域研究与开发》2009,28(2)

伴随经济全球化的发展,日本动漫作为通俗艺术、大众文化,已经突破了民族、国家和语言的障碍,为世界广泛接受.日本有"动漫王国"之称,东京因集中了日本78.8%的动漫企业被称为"动漫之都".东京动漫产业高度集中的地理现象具有很大的研究价值.从日本动漫产业集聚的空间转移、内涵特征与组织结构,东京动漫产业集聚的空间优化以及动漫企业区位选择,试图论证东京动漫产业集聚具有历史性、地理接近性、民族文化根植性的特征.  相似文献