The primary sector in economic development: Lundahl, M. (ed.) London and Sydney: Croom Helm, 1985. 408 pp. £25.00 hardback.     

George Cho 《Applied geography (Sevenoaks, England)》1986,6(4)

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Rubber movements in a marketing network: smallholders in Peninsular Malaysia     

George Cho 《Applied geography (Sevenoaks, England)》1982,2(3):189-206

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Toward the optimization of PC-based training     

Kohei Cho  Shunji Murai 《ISPRS Journal of Photogrammetry and Remote Sensing》1997,52(6):247-252

Since 1992, the National Space Development Agency of Japan (NASDA) and the Economic and Social Commission for Asia and the Pacific (ESCAP) have been co-organising the Regional Remote Sensing Seminar on Tropical Ecosystem Management (Program Chairman: Prof. Shunji Murai) every year in some country in Asia. In these seminars, the members of the ISPRS Working Group VI/2 ‘Computer Assisted Teaching’ have been performing a PC-based hands-on-training on remote sensing and GIS for beginners. The main objective of the training was to transfer not only knowledge but also the technology of remote sensing and GIS to the beginners. The software and CD-ROM data set provided at the training were well designed not only for training but also for practical data analysis. This paper presents an outline of the training and discusses the optimisation of PC-based training for remote sensing and GIS.  相似文献   

Origin of cyclicity in Triassic-Jurassic radiolarian bedded cherts of the Mino accretionary complex from Japan     

Rie S.  Hori Chang-Fee  Cho Hiroyuki  Umeda 《Island Arc》1993,2(3):170-180

Abstract The abundance of magnetic microspherules in a Triassic-Jurassic continuous sequence of alternating chert and shale beds in the Mino accretionary complex, central Japan, was measured systematically. Depending on time, the magnetic microspherules extracted from shale beds change in abundance considerably from the minimum 0.9ppm/cm³ at latest Triassic ( ca 208Ma) and the maximum 75ppm/cm³ at late Early Jurassic ( ca 187Ma); however, the abundance is always higher approximately 10–100 (average 70) times than those from adjacent chert bed at any stratigraphic horizon. Such systematic difference reveals the origin of radiolarian bedded chert as cyclic-rapid accumulation of biogenic SiO₂ under extremely slow accumulative environments of shale with probable aeolian dust in origin. The accumulation data for individual shale and chert beds were obtained based on the microspherule abundance and radiolarian biostratigraphy, i.e., ca 0.018g/cm²Ka for lower Jurassic shale beds and ca 1.9g/cm²Ka for adjacent chert beds.
Duration time to make a chert-shale couplet corresponds to a dominantly 15–20Ka interval (average 23 Ka) in Upper Triassic bedded cherts with a low paleolatitude, whereas a 40–45 Ka interval (average 42 Ka) in Lower Jurassic ones which may been formed in higher latitude than Triassics before the final accretion to the Asian continental margin. Depending on paleolatitude, the cyclicity of 23 and 42 Ka may correspond to Milankovitch cycles which have been well documented in deep-sea sediments.  相似文献   

大气层结和中尺度位温扰动对锋区多重垂直运动带形成的影响   总被引：1，自引：1，他引：1  

吕克利  H. R. Cho 《气象学报》1991,49(3):278-287

文中利用半地转锋生模式讨论了大气层结,天气尺度位温场和中尺度位温扰动对锋区多重垂直运动带形成的影响,给出了垂直运动场的演变图。结果显示,大气层结和中尺度位温扰动对锋区垂直运动带的形成有重要影响,在合适的大气层结下,垂直伸展较高的低空中尺度位温扰动是形成锋前暖区多重雨带的可能驱动机制之一;不同高度上的中尺度位温扰动以低层扰动影响最大,中层次之;天气尺度位温扰动场的水平温差对锋生速度和锋区垂直运动带都有重要影响;中尺度位温扰动对锋生速度没有什么作用。  相似文献   

An experimental investigation of heulandite-laumontite equilibrium at 1000 to 2000 bar P fluid     

M. Cho  S. Maruyama  J. G. Liou 《Contributions to Mineralogy and Petrology》1987,97(1):43-50

The univariant reaction governing the upper stability of heulandite (CaAl₂Si₇O₁₈·6H₂O), heulandite=laumontite+3 quartz+2H₂O (1), has been bracketed through reversal experiments at: 155±6° C, 1000 bar; 175±6° C, 1500 bar; and 180±8° C, 2000 bar. Reversals were established by determining the growth of one assemblage at the expense of the other, using both XRD and SEM studies. The standard molal entropy of heulandite is estimated to be 783.7±16 J mol^–1 K^–1 from the experimental brackets. Predicted standard molal Gibbs free energy and enthalpy of formation of heulandite are –9722.3±6.3 kJ mol^–1 and –10524.3±9.6 kJ mol^–1, respectively. The reaction (1), together with the reaction, stilbite=laumontite+3 quartz+3 H₂O, defines an invariant point at which a third reaction, stilbite=heulandite+ H₂O, meets. By combining the present experimental data with past work, this invariant point is located at approximately 600 bar and 140° C. Heulandite, which is stable between the stability fields of stilbite and laumontite, can occur only at pressures higher than that of the invariant point, for = P _total.These results are consistent with natural parageneses in low-grade metamorphic rocks recrystallized in equilibrium with an aqueous phase in which is very close to unity.  相似文献   

Cumulus cloud population and its parameterization     

Han-Ru Cho 《Pure and Applied Geophysics》1975,113(1):837-849

The latent heat released by cumulus clouds is very important to the energies of many large-scale tropical disturbances. The number of cumulus clouds involved in these disturbances is usually very large. The collective effects of cumulus clouds must therefore be incorporated into a large-scale model in a parameterized fashion. Present parameterization schemes are briefly reviewed. Recent advances in our understanding of the control and feedback processes between cumulus clouds and the large-scale circulations are discussed. Emphasis is placed on the implications of the results of recent diagnostic studies on the future development of the theory of cumulus parameterization.  相似文献   

Artificial neural networks for predicting DGPS carrier phase and pseudorange correction   总被引：2，自引：2，他引：0  

Arif Indriyatmoko  Taesam Kang  Young Jae Lee  Gyu-In Jee  Yong Beom Cho  Jeongrae Kim 《GPS Solutions》2008,12(4):237-247

Artificial neural networks (ANNs) were used to predict the differential global positioning system (DGPS) pseudorange and carrier phase correction information. Autoregressive moving average (ARMA) and autoregressive (AR) models were bounded with neural networks to provide predictions of the correction. The neural network was employed to realize time-varying implementation. Online training for real-time prediction of the carrier phase enhances the continuity of service of the differential correction signals and, therefore, improves the positioning accuracy. When the correction signal from the DGPS was lost, the artificial neural networks predicted the correction data with good accuracy for the navigation system during a limited period. Comparisons of the prediction results using the two models are given.

Young Jae LeeEmail:

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LAI and chlorophyll estimation for a heterogeneous grassland using hyperspectral measurements   总被引：10，自引：0，他引：10  

Roshanak Darvishzadeh  Andrew Skidmore  Martin Schlerf  Clement Atzberger  Fabio Corsi  Moses Cho 《ISPRS Journal of Photogrammetry and Remote Sensing》2008,63(4):409-426

The study shows that leaf area index (LAI), leaf chlorophyll content (LCC) and canopy chlorophyll content (CCC) can be mapped in a heterogeneous Mediterranean grassland from canopy spectral reflectance measurements. Canopy spectral measurements were made in the field using a GER 3700 spectroradiometer, along with concomitant in situ measurements of LAI and LCC. We tested the utility of univariate techniques involving narrow band vegetation indices and the red edge inflection point, as well as multivariate calibration techniques, including stepwise multiple linear regression and partial least squares regression. Among the various investigated models, CCC was estimated with the highest accuracy (, ). All methods failed to estimate LCC (), while LAI was estimated with intermediate accuracy ( values ranged from 0.49 to 0.69). Compared with narrow band indices and red edge inflection point, stepwise multiple linear regression generally improved the estimation of LAI. The estimations were further improved when partial least squares regression was used. When a subset of wavelengths was analyzed, it was found that partial least squares regression had reduced the error in the retrieved parameters. The results of the study highlight the significance of multivariate techniques, such as partial least squares regression, rather than univariate methods such as vegetation indices in estimating heterogeneous grass canopy characteristics.  相似文献   

Centrifuge modeling of seismic response of normally consolidated deep silt deposit     

Jin-Tae Han  Taesik Kim  Wanjei Cho 《Acta Geotechnica》2016,11(1):71-81

Observations from recent earthquakes in Taiwan and Turkey have shown that current methodology to determine the liquefaction susceptibility of fine-grained soils is no longer sufficient to quantify seismic hazard, and that low plasticity fine-grained soils such as silts could also cause adverse effects on the performance of civil infrastructures. It is very important to understand the dynamic behavior of silt deposit because most of coastal areas, where there are many ongoing construction activities, consist mainly of silts, which might be vulnerable to earthquake loadings. This paper presents the experimental results of centrifuge tests on reconstituted specimen to investigate the dynamic response of normally consolidated deep silt deposit in Seattle area. The experimental sequence and preparation of the artificial silt deposit are described in detail. The recorded downhole accelerations are utilized to identify variation of shear modulus and damping ratio with shear strain amplitude via inverse analysis techniques applied to dense instrumentation arrays in a dynamic centrifuge model test.  相似文献