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Science China Earth Sciences 2016年第2期59卷 307-319页

作者： LIU Ye GUO WeiDong SONG YaoMing Institute for Climate and Global Change Research School of Atmospheric Sciences Nanjing University College of Atmospheric Science Nanjing University of Information Science and Technology

Uncertainties in some key parameters in land surface models severely restrict the improvement of model capacity for successful simulation of surface-atmosphere interaction. These key parameters are related to soil moisture and heat transfer and phy- sical processes in the vegetation canopy as well as other important aerodynamic processes. In the present study, measurements of surface-atmosphere interaction at two observation stations that are located in the typical semi-arid region of China, Tongyu Station in Jilin Province and Yuzhong Station in Gansu Province, are combined with the planetary boundary layer theory to estimate the value of two key aerodynamic parameters, i.e., surface roughness length zorn and excess resistance κB-1. Multiple parameterization schemes have been used in the study to obtain values for surface roughness length and excess resistance κB-1 at the two stations. Results indicate that Zorn has distinct seasonal and inter-annual variability. For the type of surface with low-height vegetation, there is a large difference between the default value of Zorn in the land surface model and that obtained from this study, κB-1 demonstrates a significant diurnal variation and seasonal variability. Using the modified scheme for the estimation of Zom and κB-1 in the land surface model, it is found that simulations of sensible heat flux over the semi-arid region have been greatly improved. These results suggest that it is necessary to further evaluate the default values of various parameters used in land surface models based on field measurements. The approach to combine field measurements with atmospheric boundary layer theory to retrieve realistic values for key parameters in land surface models presents a great potential in the improvement of modeling studies of surface-atmosphere interaction.

关键词： Semi-arid region Turbulent transfer Surface roughness length Excess resistance field experiments

Engineering application of submerged water jets for sediment removal in a tidal riverbed

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Water Science and Engineering 2022年第4期15卷 348-357页

作者： Chaiyuth Chinnarasri King Mongkut's University of Technology Thonburi Bangkok 10140Thailand

Sediment deposition problems have attracted the interest of engineers and *** experimental studies have been conducted on scour depth using turbulent ***,field observation and monitoring have rarely been *** study aimed to eliminate sediments on a tidal riverbed using a prototype device,which consisted of a set of submerged vertical water nozzles and submerged horizontal air *** effectiveness of the water jet in sediment removal during spring and neap tides was *** quantitative relationships of dimen-sionless parameters,such as(1)the relative sediment scour volume versus the number of flows from the jet exit,(2)the relative sediment scour volume versus the relative scour depth,and(3)the relative scour size versus the relative jet intensity,were *** results showed that the freshwater flowing to the sea affected the sediment scour volume during the falling cycle of spring *** contrast,the rising cycle of spring tides retarded the freshwater flow,resulting in a decrease in the sediment scour volume.A steep water surface slope accelerated the river flow and further influenced the cross-flow current around the study *** a result,a highly diffusive turbulent flow was produced,causing sus-pended sediments to be rapidly removed from the scour hole *** increase in the number of flows from the jets led to intensified diffusion of turbulent energy into the *** rapidly varying water depth caused jet energy to be dissipated before approaching the riverbed,and it significantly affected the scour process during the spring-tide *** proposed equations can be used to estimate the scour volume,scour size,and re-suspended sediments in tidal rivers within defined ranges of parameters.

关键词： Jet diffusion Scour hole Sediment re-suspension Tidal river field experiments

Population response of rodents to control with rodenticides

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Current Zoology 2009年第2期55卷 81-91页

作者： S.A. SHILOVA A.V. TCHABOVSKY A.N. Severtsov Institute of Ecology and Evolution 33

We summarize theoretical approaches and practice of rodent pest control in Russia and former USSR during last 50 years. We review literature as well as original data to understand mechanisms of rodent populations recovery after chemical control campaigns in urban areas, agricultural lands and natural foci of plague. Laboratory and field experiments indicate that inherent individual variation in behavioural, physiological and life-history traits provides survival of heterogeneous mix of individuals in residual population with increased resistance to poisonous baits and high reproductive potential that leads to fast recovery of a population. In a series of field experiments with various rodent and lagomorph species （Mus musculus, Rattus norvegicus, Meriones unguiculatus, M. meridianus, M. tamariscinus, Ochotona pallasii ） we have shown that patterns of recolonization of depopulated area and mechanisms of population recovery vary among species and depend on species-specific social organization. After control territorial and group-living species demonstrated an increase in mobility and affiliative and marking behaviour and a decrease in intraspecific aggression. The rate of recolonization of treated areas was high due to redistribution of survived individuals and immigration by neighbors. Population recovered to original level due to increased breeding performance and fecundity of both survived residents and immigrants. In contrast, socially-independent species exhibited minor changes in behaviour. Recolonization was mainly due to better survival and recruitment of youngs, so the rate of recolonization was low. Species-specificity of behavioural compensation mechanisms to control should be considered when developing ecologically based rodent management strategies

关键词： Rodent control Compensation mechanisms Rodenticides field experiments

Design and experiment of the side insertion horizontal transplanting device for sweet potato(Ipomoea batatas Lam.)seedlings on mulch film

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International Journal of Agricultural and Biological Engineering 2023年第6期16卷 148-157页

作者： Wanzhi Zhang Qian Zhu Dameng Ge Dehui Zheng Tingting Zhang College of Mechanical and Electronic Engineering Shandong Agricultural UniversityTai'an 271018ShandongChina Sinotruk Taian Wuyue Special Vehicle Co. LtdTai'an 271018ShandongChina Taishan Polytechnic Tai'an 271018ShandongChina

Side insertion horizontal transplanting sweet potato seedlings on mulch film is one kind of new planter pattern,which keeps the soil warm and moist restraining the infestation of pests and weeds,realizing dense transplanting and ensuring uniformity of sweet potato ***,a side insertion horizontal transplanting device for sweet potato seedlings on mulch film was designed,including the details and parameters of the reciprocating mechanism and the seedling clamping *** the two mechanisms and the whole device were simulated and the test bench was built for field experiments to detect if this device can meet the agronomic *** simulation results show that the designed device is in accordance with the agronomic requirements of horizontal transplanting,transplanting depth and transplanting length,and is potential for achieving rational close *** lateral length of the designed transplanting device is extended at about 90 mm compared with previous machine,which will promote the number of soil nodules of sweet potato seedlings and the growth of production *** horizontal velocity of the transplanting claw is−17 mm/s when picking the seedling,the horizontal velocity of the transplanting claw 645 mm/s and the vertical velocity 83 mm/s when releasing the *** data could ensure the accuracy requirements of horizontal transplanting *** field experiment results show the expulsion rate of sweet potato seedlings at 1.38%,the qualified rate of transplanting length and depth at 94.17%and 95.11%respectively,the average length and width of the mulch film breaking hole at 44.67 mm and 43.00 mm in *** postures of the actual transplanted seedlings are consistent with the simulation results,meeting the requirements of horizontal transplanting with less damage to the mulch *** designed transplanting device lays a foundation for the development of sweet potato seedlings side transplanting machine.

关键词： sweet potato seedlings Transplanting device mechanism design motion simulation field experiments

Short-and long-term behaviors of drifts in the Callovo-Oxfordian claystone at the Meuse/Haute-Marne Underground Research Laboratory

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Journal of Rock Mechanics and Geotechnical Engineering 2013年第3期5卷 221-230页

作者： G.Armand A.Noiret J.Zghondi D.M.Seyedi ANDRA R&D Meuse/Haute-Marne Underground Research Laboratory ANDRA R&D

Since 2000, the French National Radioactive Waste Management Agency （ANDRA） has been constructing an Underground Research Laboratory （URL） at Bure （east of the Paris Basin） to perform experiments in order to obtain in situ data necessary to demonstrate the feasibility of geological repository in the Callovo- Oxfordian claystone. An important experimental program is planned to characterize the response of the rock to different drift construction methods, Before 2008, at the main level of the laboratory, most of the drifts were excavated using pneumatic hammer and supported with rock bolts, sliding steel arches and fiber shotcrete. Other techniques, such as road header techniques, stiff and flexible supports, have also been used to characterize their impacts. The drift network is developed following the in situ major stresses. The parallel drifts are separated enough so as they can be considered independently when their hydromechanical （HM） behaviors are compared. Mine-by experiments have been performed to measure the HM response of the rock and the mechanical loading applied to the support system due to the digging and after excavation. Drifts exhibit extensional （mode I） and shear fractures （modes II and III） induced by excavation works. The extent of the induced fracture networks depends on the drift orientation versus the in situ stress field. This paper describes the drift convergence and deformation in the surrounding rock walls as function of time and the impact of different support methods on the rock mass behavior. An observation based method is finally applied to distinguish the instantaneous and time-dependent parts of the rock mass deformation around the drifts.

关键词： field experiments Claystone Tunnel convergence Induced fractures Short- and long-term behaviors

The multi-dimensional effects of reciprocity on worker effort:evidence from a hybrid field-laboratory labour market experiment

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Economic and Political Studies 2021年第1期9卷 37-67页

作者： Min-Taec Kim Robert Slonim New South Wales Bureau of Crime Statistics SydneyAustralia Faculty of Arts and Social Sciences University of SydneySydneyAustralia

We examine the gift exchange hypothesis on both the quantity and quality of work using a hybrid field-laboratory labour market *** recruited participants to enter survey data for a well-known charitable *** were paid either a high or low *** find that although the total number of surveys entered did not vary in terms of wages,high wage workers made fewer errors and entered more surveys after controlling for *** further find that for low costs associated with errors,offering a low wage maximises profits;but for higher costs,paying a high‘gift exchange’wage maximises profits.

关键词： Gift exchange reciprocity multi-tasking laboratory field experiments

Do Aid Donors Plant the Grassroots？ Evidence from a Randomized field Experiment in the US and Uganda

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International Relations and Diplomacy 2015年第3期3卷 192-208页

作者： Danny Walker George Washington University Washington USA

Recent literature dealing with nongovemmental organizations （NGOs） claims that NGOs have little incentive to base their decisions and strategies on local needs and instead are governed largely by their current and prospective donors （McGann ＆ Johnstone, 2006; Prakash ＆ Gugerty, 2010; Bollen et al., 2005）. To test this claim, I have created a quantitative experiment in the US and Uganda in which organizations were randomly assigned to a control group or one of four treatment groups based on the main stakeholders of the NGO market---donors, local government officials, project beneficiaries, and NGO peers. In each group, organizations were invited to take a survey and were told that the results of their survey would be published to one of these four stakeholder groups. Thus, differences in response rates between groups are attributed to differences in the degree of concern that NGOs felt about the opinions of a given stakeholder. I hypothesized that NGOs care more about the opinions of their donors than other stakeholder groups and found support for this hypothesis among NGOs in the US.

关键词： Nongovernmental organizations field experiments aid accountability Uganda

Compounds screened to monitor the gypsy moth,Lymantria dispar

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Compounds screened to monitor the gypsy moth,Lymantria dispa...

IMPACT OF DRAINAGE ACTIVITIES ON CLAY SOILS, HYDROLOGY AND SOLUTE LOADS ON SURFACE WATER

第三届全国生物入侵大会

作者： Yan-xue Yu~1,Cheng-yu Yang~2,Nai-zhong Chen~1 1 Chinese Academy of Inspection and Quarantine, 2 Qinhuangdao Entry-Exit Inspection and Quarantine Bureau,

The gypsy moth Lymantria dispar,as one of trade barriers,widely distribute in *** monitoring materials have some disadvantages,which can not sensitively monitor the moth, particularly the *** new types of compounds need exploring to effectively monitor both female and *** compounds were screened according to the mechanism of olfaction of *** the sequences of pheromone-binding proteins were identified,the structures of them were built by homology models,the compounds were screened using the software of Discovery Studio 2.5.,and 20 compounds were screened to do the fluorescence binding assay and field *** the fluorescence binding assay and the electrophysiological experiments were both to make sure how many compounds using in the ***,we got four compounds to do field experiments,there are 1, 2-epoxy-9-decene,1,2-epoxy-5-hexene,1,2-epoxyoctadecane,and 1,*** results showed that 1,2-epoxy-9-decene can effectively monitor both female and male of *** experiment will be improved in the *** work can not only get some putative chemicals to explore the new lure,but also decrease the flow of experiments.

关键词： Lymantria dispar Monitoring materials Pheromone-binding proteins field experiments

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IMPACT OF DRAINAGE ACTIVITIES ON CLAY SOILS, HYDROLOGY AND S...