Rare earth elements in Silurian pelitic schists from N.W. Maine     

Robert L Cullers  Long-Tsu Yeh  Sambhudas Chaudhuri  Charles V Guidotti 《Geochimica et cosmochimica acta》1974,38(3):389-400

Thirty-two samples of a series of metamorphosed Silurian (?) pelitic schists in the greenschist and amphibolite facies from N.W. Maine have been analyzed for their rare-earth element (REE) content. The REE contents of these samples do not change as a function of metamorphic grade. Two different metasedimentary formations have been sampled, and they differ significantly in their light REE content. The absolute and relative distribution of the REE in the Bangeley Formation are quite similar to the composites of N. American, European and Russian shales that have been determined thus far (e.g. median La/Lu ratio of the Bangeley Formation normalized to chondrites = 8.7 ± 3.0). Samples from the Perry Mt. Formation show large depletions in the light REE compared to the Bangeley Formation and previously analyzed shale and metamorphosed shale samples, but heavy REE concentrations that are quite similar to the other samples (e.g. median La/Lu ratio of the Perry Mt. normalized to chondrites = 1.2 ± 0.6). These differences in light REE content between the Perry Mt. Formation and other sedimentary rocks are probably due to differences in the original clay mineral compositions as modified by weathering and/or depositional environments.  相似文献   

A discrete space continuous time modeling approach to nonsteady flow in a leaky aquifer system of finite configuration     

Miguel A. Marino  Willian W-G. Yeh 《Journal of Hydrology》1973,20(3):255-266

Existing analytical procedures for nonsteady flow in a leaky confined aquifer assume that the aquifer system is areally infinite. A technique is presented that treats a leaky confined aquifer system of finite configuration. By means of a discrete space continuous time (DSCT) modeling approach, the partial differential equation governing the flow system is transformed into a set of ordinary differential equations that can be easily integrated numerically on a high speed digital computer using available scientific subroutines. The finite difference formulation is in effect an explicit scheme. A criterion is developed for which the scheme is computationally stable. A numerical example is presented.  相似文献   

Reliability analysis of hydraulic structures considering unit hydrograph uncertainty     

B. Zhao  Y. -K. Tung  K. -C. Yeh  J. -C. Yang 《Stochastic Environmental Research and Risk Assessment (SERRA)》1997,11(1):33-50

Unit hydrographs (UHs), along with design rainfalls, are frequently used to determine the discharge hydrograph for design and evaluation of hydraulic structures. Due to the presence of various uncertainties in its derivation, the resulting UH is inevitably subject to uncertainty. Consequently, the performance of hydraulic structures under the design storm condition is uncertain. This paper integrates the linearly constrained Monte-Carlo simulation with the UH theory and routing techniques to evaluate the reliability of hydraulic structures. The linear constraint is considered because the water volume of each generated design direct runoff hydrograph should be equal to that of the design effective rainfall hyetograph or the water volume of each generated UH must be equal to one inch (or cm) over the watershed. For illustration, the proposed methodology is applied to evaluate the overtopping risk of a hypothetical flood detention reservoir downstream of Tong-Tou watershed in Taiwan.  相似文献   

The 1994 Shikotan earthquake tsunamis   总被引：1，自引：0，他引：1  

Harry Yeh  Vasily Titov  Viacheslav Gusiakov  Efim Pelinovsky  Vasily Khramushin  Victor Kaistrenko 《Pure and Applied Geophysics》1995,144(3-4):855-874

The 1994 Shikotan earthquake was one of the greatest earthquakes in recent years with a magnitude ofM _s 8.0. A tsunami survey was conducted by Russian and U.S. geophysicists from October 16–30, 1994, less than two weeks after the earthquake. The survey results and a numerical hindcast simulation are reported. Tsunami focusing effect at locations supposedly sheltered by the island chain is discussed. Based on the obtained data, tsunamis which attacked Shikotan Island are characterized as long waves (the order of 10–20 min wave period) with a positive leading wave. Possible consequences of the positive leading wave form are discussed in relation to the observed minimal destruction of beach vegetation and relatively small transport of marine sediment onto the shore. The high-quality tide-gage record in Malokurilskaya Bay indicates the occurrence of a 53 cm subsidence at the site.  相似文献   

An analytical solution for modeling thermal energy transfer in a confined aquifer system     

Yang Shaw-Yang  Yeh Hund-Der 《Hydrogeology Journal》2008,16(8):1507-1515

A mathematical model is developed for simulating the thermal energy transfer in a confined aquifer with different geological properties in the underlying and overlying rocks. The solutions for temperature distributions in the aquifer, underlying rock, and overlying rock are derived by the Laplace transforms and their corresponding time-domain solutions are evaluated by the modified Crump method. Field data adopted from the literature are used as examples to demonstrate the applicability of the solutions in modeling the heat transfer in an aquifer thermal energy storage (ATES) system. The results show that the aquifer temperature increases with time, injection flow rate, and water temperature. However, the temperature decreases with increasing radial and vertical distances. The heat transfer in the rocks is slow and has an effect on the aquifer temperature only after a long period of injection time. The influence distance depends on the aquifer physical and thermal properties, injection flow rate, and injected water temperature. A larger value of thermal diffusivity or injection flow rate will result in a longer influence distance. The present solution can be used as a tool for designing the heat injection facilities for an ATES system.  相似文献   

Evidence of the observed change in the atmosphere–ocean interactions over the South China Sea during summer in a regional climate model     

Hye-Yeong Jang  Sang-Wook Yeh  Eun-Chul Chang  Baek-Min Kim 《Meteorology and Atmospheric Physics》2016,128(5):639-648

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Threshold of the volcanic forcing that leads the El Niño-like warming in the last millennium: results from the ERIK simulation     

Hyung-Gyu Lim  Sang-Wook Yeh  Jong-Seong Kug  Young-Gyu Park  Jae-Hun Park  Rokjin Park  Chang-Keun Song 《Climate Dynamics》2016,46(11-12):3725-3736

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The impact of internal atmospheric variability on the North Pacific SST variability     

S.-W. Yeh  B. P. Kirtman 《Climate Dynamics》2004,22(6-7):721-732

The impact of internal atmospheric variability on North Pacific sea surface temperature (SST) variability is examined based on three coupled general circulation model simulations. The three simulations differ only in the level of atmospheric noise occuring over the ocean at the air-sea interface. The amplitude of atmospheric noise is controlled by use of the interactive ensemble technique. This technique simultaneously couples multiple realizations of a single atmospheric model to a single realization of an ocean model. The atmospheric component models all experience the same SST, but the ocean component is forced by the ensemble averaged fluxes thereby reducing the impact of internal atmospheric dynamics at the air-sea interface. The ensemble averaging is only applied at the air-sea interface so that the internal atmospheric dynamics (i.e., transients) of each atmospheric ensemble member is unaffected. This interactive ensemble technique significantly reduces the SST variance throughout the North Pacific. The reduction in SST variance is proportional to the number of ensemble members indicating that most of the variability can simply be explained as the response to atmospheric stochastic forcing. In addition, the impact of the internal atmospheric dynamics at the air-sea interface masks out much of the tropical-midlatitude SST teleconnections on interannual time scales. Once this interference is reduced (i.e., applying the interactive ensemble technique), tropical-midlatitude SST teleconnections are easily detected.  相似文献   

Influence of Velocity and Types of Beam Trawl Towing on Deep-Sea Demersal Fish and Decapod Crustacean Samples   总被引：3，自引：0，他引：3  

Hsin-Ming Yeh  Suguru Ohta 《Journal of Oceanography》2002,58(3):505-517

The sampling efficiency of two types of beam trawl towed at different velocities was compared when sampling deep-sea demersal fish and decapod crustaceans. The trawls were a Sigsbee-Agassiz type of 2 m span, and an Oregon type of 3 m span. The different hauls caught by the Oregon type beam trawl of 3 m span towed at 1.5 knot (3m 1.5 kt), the Oregon type towed at 0.8 knot (3m 0.8 kt) and the Sigsbee-Agassiz type towed at 1.5 knot (2m 1.5 kt) were compared by analysis of variance (ANOVA), the Tukey test, cluster analysis based on Morisita-Horn index, and correspondence analysis. The minimum viable sample size was determined by a randomization test. For demersal fish, the type of gear used had more influenced on the samples obtained than the towing velocity. For decapod crustaceans, no significant difference was detected between different trawls towed at different velocities. The common idea that if these types of trawl are towed at 1 knot or more, they cannot efficiently sample epifauna, but demersal fish can be well sampled, should be abandoned. The samples of demersal fish caught by 3m 1.5 kt revealed the greatest consistency and lowest variation than the others. We recommend using an Oregon type beam trawl of 3 m span towed at 1.5 knot as an ordinary deep-sea sampling device. Only a single successful haul or a sample size of 52 individuals was sufficient for estimating demersal fish diversity, but at least two successful hauls or a sample size of 54 individuals were needed for decapod crustaceans. If possible, seven successful hauls or a sample size of 189 individuals of decapod crustaceans are recommended for community study. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

A case study of strut-free excavation retaining system     

Yeh  Tzu-Yuan  Ou  Chang-Yu  Lim  Aswin 《Acta Geotechnica》2022,17(12):5557-5571

Acta Geotechnica - This paper presents a successful design of a strut-free excavation retaining system, namely the TPKE project. The TPKE excavation project was 13.2 m deep, covering...  相似文献