The work of the Japanese Specialists for New Khmer Architecture in Cambodia

Cross cultural exchanges are an important aspect in the development of modern architecture. Multiple flows of ideas have shaped the architecture of Cambodia in the second half of the 20th century. Western designers shaped Cambodia’s architectural and urban form, but the country also saw collaboration from Japanese practitioners and this paper explores their respective roles and paradigms. Helen Grant Ross and Darryl Leon Collins, for example, regarded the 1960s as the age of New Khmer Architecture in Cambodia. They have explored the French-educated architect young Cambodian leader Vann Molyvann, who led this age as an architect-administrative official. However the fact that there were some Japanese architects who collaborated on some of these projects is not well known. In particular, Gyoji Banshoya (1930-1998) and Nobuo Goto (1938-2000), two students of the Japanese leading architect Kiyoshi Seike, officially participated in projects during the 1960s and wrote plans, reports and articles. Based on new resources found in the private libraries of the Japanese planners, this paper discusses Modern Khmer Architecture based on the largely unknown fact that some Japanese architects participated in projects in Cambodia. The question of how to manage the modernization of historical spatial composition of cities was a common interest shared by the French, the Japanese and the Cambodians alike. This paper explores the international context of building in Cambodia including the movements of CIAM members, including the French planner Gerald Hanning, the participation of Banshoya, and the supervision by Vann Molyvann. It specifically explores how the Japanese architects, Banshoya and Goto, contributed to the projects in Cambodia in the 1960s, the age of Modern Khmer Architecture. Banshoya participated in huge projects such as the stadium, collective houses and master plans. Goto also supported the work of Banshoya. He investigated his own interests and found his own way with his experimental habitat. What is important is that these French-influenced Japanese architects cherished the historical composition of Asian or local space and incorporated it in their modern planning policy. A specific example is Banshoya’s first piece “the Square House” which was a low cost house which harmonized Japanese tradition and modernism. His work in Algiers titled “Temporary Housing Replacing Tin-Roofed Shelters” adopted the traditional housing plan with patio supporting the separation of public and private spaces. In Cambodia, under the supervision of Banshoya, the more senior Goto tried to reconstitute the spatial composition of the traditional Khmer house and suggested plans for modern Khmer house and housing areas. Banshoya completed his mission in the ancient French protectorate of Cambodia and his projects were also related to some of the heritage of CIAM. Banshoya’s mission in Cambodia was limited to 1 year, but it was significant as his first assignment as a UNDP specialist. He continued as a UNDP specialist untill the 1970s when he elaborated the master plan of Aleppo. This paper focuses on the cross-cultural investigation of the Cambodian projects and therewith lays the foundation for new analytical perspectives of the master plans in Beirut, Damascus and Aleppo

The role of post-war reconstruction planning in Hiroshima' image-shift to a Peace Memorial City

In the wake of war, cities’ path to recovery is hindered by a large-scale destruction which is usually combined with issues such as post-war financial difficulties, and complex property rights. During reconstruction, urban areas encounter different drivers of recovery that define the future direction o

Slum toponymy in Nairobi: A cultural arena for socio-political justice and symbolic resistance

Slum dwellers in Nairobi, despite making up half of the city’s population , are a socially, politically and economically marginalised group. There are an estimated 134 slums which occupy about 1% of the city area . Much research has been done on the challenges facing slum dwellers with an aim to improve their living conditions. This study aims to contribute to that effort by analysing how the names of places (toponymy) within slums, can be used to explain the challenges of these settlements from the vantage point of the namers – the residents themselves. The name then becomes an illuminating social code as regards the spatial organization of the slums . Typically, slums in Nairobi are named after the original settlers (Mukuru -kwa Reuben and kwa Njenga), geographical conditions (Kibera, Mashimoni), other places (Beirut, Kosovo and Vietnam) or past local and global events (Soweto Uprising in South Africa). Other names are a blend of one or more things or could mean different things at the same time. For instance Kosovo, Vietnam and Soweto, could be references to the wars and uprising and not the locations themselves. These examples evidence the inclination of slum toponymy towards places or events associated with social-political struggles. It is on this premise that we look at the symbology behind the names, what they communicate about the lives of the residents and their resilience in the face of many socio-political and economic challenges. In this study we will take Kibera as a specific case. It is the largest slum in Kenya and Africa. Data on Kibera was obtained through: archival research, a Focused Group Discussion held with the Nubian Council of elders, and field surveys in September 2015. Analysis was done through toponymic layering to show how names have evolved along a time-space continuum. These toponymic layers were further analysed along ethnic, political, geographical and historical axes to understand their meanings and implications on space. The study showcases the cultural and social resistance and resilience of urban slum dwellers in Nairobi. Toponymic resistance (warfare) is seen through: use of global names associated with conflict to highlight their plight, refusal to use names imposed by government, or the use of ethnic names in order to mark spatial territories. All these struggles are embedded within the spatial toponymic framework of Nairobi slums.

A study on urban planning history in the Middle East based on the international cooperation and its reflection to urban conservation projects

科学研究費助成事業(科学研究費補助金)研究成果報告書：若手研究(B)2010-2011課題番号：2276045

Evaluation of the effectiveness of X-ray protective aprons in experimental and practical fields

Few practical evaluation studies have been conducted on X-ray protective aprons in workplaces. We examined the effects of exchanging the protective apron type with regard to exposure reduction in experimental and practical fields, and discuss the effectiveness of X-ray protective aprons. Experimental field evaluations were performed by the measurement of the X-ray transmission rates of protective aprons. Practical field evaluations were performed by the estimation of the differences in the transit doses before and after the apron exchange. A 0.50-mm lead-equivalent-thick non-lead apron had the lowest transmission rate among the 7 protective aprons, but weighed 10.9 kg and was too heavy. The 0.25 and 0.35-mm lead-equivalent-thick non-lead aprons differed little in the practical field of interventional radiology. The 0.35-mm lead apron had lower X-ray transmission rates and transit doses than the 0.25-mm lead-equivalent-thick non-lead apron, and each of these differences exceeded 8 % in the experimental field and approximately 0.15 mSv/month in the practical field of computed tomography (p < 0.01). Therefore, we concluded that the 0.25-mm lead-equivalent-thick aprons and 0.35-mm lead apron are effective for interventional radiology operators and computed tomography nurses, respectively

A method for quantification of noise non-uniformity in computed tomography images: A computational study

In computed tomography (CT), the noise is sometimes non-uniform, i.e. the noise magnitude may vary with the gradient level within the image. The purpose of this study was to quantify the noise non-uniformity in CT images using appropriate 1D and 2D computational phantoms, and to validate the effectiveness of the proposed concept in images filtered by the bilateral filter (BF), as an example of a non-linear filter. We first developed 1D and 2D computational phantoms, and Gaussian noises with several noise levels were then added to the phantoms. In addition, to simulate the real form of noise from images obtained in a real CT scanner, a homogeneous water phantom image was used. These noise levels were referred to as ground truth noise (σG). The phantoms were then filtered by the bilateral filter with various pixel value spreads (σ) to produce non-uniform noise. The original gradient phantoms (G) were subtracted from both the noisy phantoms (IN) and the filtered noisy phantoms (IBF), and the magnitudes of the resulting noise for each gradient were computed. The noise-gradient dependency (NGD) curve was used to display the dependency of noise magnitude on image gradient in the non-uniform noise. It is found that for uniform noise, the magnitude of noise was constant for all gradients. However, for non-uniform noise, the measured noise was dependent on the gradient levels and on the strength of the BF for every ground truth noise (σG). It was found that the noise magnitude was large for the large gradients and decreased with the magnitude of the image gradient

Long-term stability of beam quality and output of conventional X-ray units

Conventional diagnostic X-ray units are used for radiographic imaging in many countries. For obtaining entrance surface doses, a numerical dose determination method has been applied in Japan. Although this technique is effective, it has to account for errors, particularly fluctuations, due to the beam quality and output of X-ray tubes. As a part of our quality control procedures, we recorded the entrance surface air kerma, tube voltage, and half-value layer measurements made for four diagnostic X-ray tubes over a 103-week period. The entrance surface air kerma for one of the four X-ray tubes had increased significantly by 11.4 % over 1 year from its initial setting, whereas the tube voltages and half-value layers did not deviate significantly from their initial values. Medical physicists and radiological technologists should be aware of this fluctuation for diagnostic X-ray tubes and take it into consideration when calculating the entrance surface air kerma. © 2014 Japanese Society of Radiological Technology and Japan Society of Medical Physics.発行後1年より全文公

Where should we measure the entrance air kerma rate during acceptance testing of the automatic dose control of a fluoroscopic system?

In Japan, the entrance air kerma rate (EAKR) to a patient cannot exceed 50 mGy/min in conventional fluoroscopy. However, it is unclear where the EAKR should be measured. We obtained the tube potential and tube current as a function of polymethylmethacrylate (PMMA) thickness, and the EAKR at the interventional reference point (IRP) was measured from the trajectory. The EAKR at the point established by the U.S. Food and Drug Administration (FDA) was calculated from EAKR at the IRP. The EAKR at the IRP exceeded the limit at a PMMA thickness of 22-28 cm. However, the EAKR did not exceed the limit at the FDA point. If the EAKR to a patient is being verified to meet the recent Japanese ruling, the EAKR should be measured at the FDA point, and if the EAKR is being evaluated for determination of the skin dose, it should be monitored at the IRP. © 2013 Japanese Society of Radiological Technology and Japan Society of Medical Physics

Comparison between 3-D and z-axis automatic tube current modulation technique in multidetector-row CT

取得学位 : 博士（保健学）, 学位授与番号 : 医博甲第1952号 , 学位授与年月日 : 平成20年3月22日, 学位授与大学 : 金沢大学, 審査結果の報告日 : 平成20年2月19日, 主査 :越田 吉郎 , 副査 :鈴木 正行, 真田

Noise simulation system for determining imaging conditions in digital radiography

Reduction of exposure dose and improvement in image quality can be expected to result from advances in the performance of imaging detectors. We propose a computerized method for determining optimized imaging conditions by use of simulated images. This study was performed to develop a prototype system for image noise and to ensure consistency between the resulting images and actual images. An RQA5 X-ray spectrum was used for determination of input-output characteristics of a flat-panel detector (FPD). The number of incident quantum to the detector per pixel (counts/pixel) was calculated according to the pixel size of the detector and the quantum number in RQA5 determined in IEC6220-1. The relationship among tube current-time product (mAs), exposure dose (C/kg) at the detector surface, the number of incident quanta (counts/pixel), and pixel values measured on the images was addressed, and a conversion function was then created. The images obtained by the FPD was converted into a map of incident quantum numbers and input into random-value generator to simulate image noise. In addition, graphic user interface was developed to observe images with changing image noise and exposure dose levels, which have trade-off relationship. Simulation images provided at different noise levels were compared with actual images obtained by the FPD system. The results indicated that image noise was simulated properly both in objective and subjective evaluation. The present system could allow us to determine necessary dose from image quality and also to estimate image quality from any exposure dose. © 2012 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE)