Experimental Study on the Dam-Break Hydrographs at the Gate Location

When studying the dam-break flow phenomenon,the basic hydrodynamic features of the dam-break flow at the gate location should be verified primarily.In this study,laboratory experiments were performed in a rectangular and horizontal flume with the same initial water head setting on the dry and wet downstream bed conditions.Water surface elevation was extracted through image analysis and validated by comparing with the data measured using a wave gauge.Temporal variation of the water surface elevation at the gate location,quantified in terms of high-speed video recorded images,can be divided into three stages,the sharp decreasing stage,the relatively steady stage,and the gradually decreasing stage.Applicability of several classic analytical solutions of the dam-break problem at the gate location was validated using present experimental data.Ritter's solution is effective for the dry bed condition while Stoker's solution could be applied to the wet bed case,and both are only applicable during the steady stage.Lin' solution reproduces the gate-site hydrographs well during both the relatively steady and the gradually decreasing stages,especially for the condition under which the down-upstream water depth ratio is smaller than 0.138.

Changes of Organic Matter, N, P and K Content of Soils in Red Soil Areas Under Long-Term Experiment

The content of organic matter （OM）, nitrogen （N）, phosphorus （P）, and potassium （K） in the three selected soils, including Calcaric Purpli-Orthic Primosols （purple sand-shale parent material）, Dystric Turbi-Anthric Primosols （quaternary red clay parent material） and Typic Udi-Sandic Primosols （granite parent material） were studied under a long-term experiment by using crop straw and inorganic fertilizers at the Hunan Red Soil Experiment Station of Chinese Academy of Agricultural Sciences. The results showed that the contents of OM, N, P and K in the three selected soils increased after 23 years application of crop straw and inorganic fertilizers, but the contents increased much less when crop straw or inorganic fertilizers was applied alone. The nutrient contents in the three soils developed from granite changed more remarkably than those in the soil derived from quaternary red clay and purple sand-shale. It was also found that the contents of OM, N, and P increased slightly in the treatments without applying fertilizers or returning the crop straw to the root bed. Combined application of inorganic fertilizers and crop straw could remarkably increase the contents of OM, alkalihydrolyzable N and available K, the positive correlation between application of organic fertilizers and increase of OM in soil did not always happened, it provided evidence for the relation between appropriate C/N ratio and accumulation of OM in soil. The increase of nutrient content was influenced by the soil properties. By comparing the contents of nutrient in 0-20 cm depth in the three different soils, it was concluded that the most increases of OM, alkali-hydrolyzable N, and available P were observed in Typic Udi-Sandic Primosols with the average increase by 3.03, 27.38, and 21.73 mg kg^-1, respectively. The available K increased in Dystric Turbi-Anthric Primosols with the average increase by 25.82 mg kg^-1, while it decreased in Calcaric Purpli-Orthic Primosols and Typic Udi-Sandic Primosols. It was concluded that the application of inorganic fertilizer and crop straw was important to improve the soil fertility for all of three selected soils. The straw return to the field had played a significant role for enhancement of the soil quality in the study areas. The application of inorganic fertilizer combined with the straw return to the fields could remarkably improve the soil fertility.

Crop yields and soil organic carbon dynamics in a long-term fertilization experiment in an extremely arid region of northern Xinjiang, China

A long-term fertilization experiment was set up in northern Xinjiang, China to evaluate the dynamics of crop production and soil organic carbon （SOC） from 1990 to 2012 with seven fertilization treatments. The seven treatments included an unfertilized control （CK） and six different combinations of phosphorus （P）, potassium （K）, nitrogen （N）, straw （S） and animal manure （M）. The balanced fertilization treatments had significantly （P〈0.05） higher average yields than the unbalanced ones. The treatment with 2/3 N from potassium sulfate （NPK） and 1/3 N from farmyard manure （NPKM） had a higher average yield than the other treatments. The average yields （over the 23 years） in the treatments of NPK, and urea, calcium superphosphate （NP） did not differ significantly （P〉0.05） but were higher than that in the treatment with urea and potassium sulfate （NK; P〈0.05）. The results also show that the highest increases in SOC （P〈0.05） occurred in NPKM with a potential increase of 1.2 t C/（hm2.a）. The increase in SOC was only 0.31, 0.30 and 0.12 t C/（hm2.a） for NPKS （9/10 N from NPK and 1/10 N from straw）, NPK and NP, respectively; and the SOC in the NP, NK and CK treatments were approaching equilibrium and so did not rise or fall significantly over the 23-year experiment. A complete NPK plus manure fertilization program is recommended for this extremely arid region to maximize both yields and carbon sequestration.

Location Influencing the Artistic Value

This paper stems from an artistic experiment,in which a distinguished violinist received completely different prices for performing in varying locations.This may be due to the difference in the performance locations,and the value of art in the heart of the audience.

The principles and guidelines for designing long-term agronomic experiments

Many of the important questions facing farming systems in the world today require long-term studies to provide meaningful information and answers. A long-term agronomic experiment (LTAE) should (1) have long-term objectives; (2) study important soil processes or ecological processes; and (3) be related to the productivity and sustainability of systems. A well established LTAE can provide both insights into how the system operates and foresight into where the system goes. The prerequisites for setting up a LTAE are the secured land, continuous funding and dedicated scientists. A number of principles must be considered carefully when establishing a LTAE, (1) the site must be representative of large areas; (2) the treatments should be simple, but focusing on the big questions; (3) the plots should be large enough to allow subsequent modification of the experiment if this becomes necessary; (4) crop rotations should minimise, wherever possible, the risk of build-up of pests and diseases, and rotational phase should be considered in a rotational experiment; (5) a clearly defined experimental protocol should be developed to ensure data collected is scientifically valid and statistically analysable, but with flexibility to allow essential changes; (6) soil samples, possibly plant samples, should be achieved to provide better answer to the original questions when new, perhaps more accurate analytical techniques are developed, or answer new research questions that were not considered in the original design. The MASTER experiment in Australia was used as a case study to demonstrate how these principles are implemented in practice.

A Trajectory Privacy Protection Method to Resist Long-Term Observation Attacks

Users face the threat of trajectory privacy leakage when using location-based service applications, especially when their behavior is collected and stored for a long period of time. This accumulated information is exploited by opponents, greatly increasing the risk of trajectory privacy leakage. This attack method is called a long-term observation attack. On the premise of ensuring lower time overhead and higher cache contribution rate, the existing methods cannot utilize cache to answer subsequent queries while also resisting long-term observation attacks. So this article proposes a trajectory privacy protection method to resist long-term observation attacks. This method combines caching technology and improves the existing differential privacy mechanism, while incorporating randomization factors that are difficult for attackers to recognize after long-term observation to enhance privacy. Search for locations in the cache of both the mobile client and edge server that can replace the user’s actual location. If there are replacement users in the cache, the query results can be obtained more quickly. Simultaneously obfuscating the spatiotemporal correlation of actual trajectories by generating confusion regions. If it does not exist, the obfuscated location generation method that resists long-term observation attacks is executed to generate the real anonymous area and send it to the service provider. The above steps can comprehensively protect the user’s trajectory privacy. The experimental results show that this method can protect user trajectories from long-term observation attacks while ensuring low time overhead and a high cache contribution rate.

Effects of Long-term Located Fertilization on Wheat Yield and Soil Nutrients of Three Types of Soils in Shandong Province

[Objective] This study aimed to investigate the effects of long-term differ- ent fertilization in three types of soils on wheat yield and soil nutrient variation in Shandong Province. [Method] A 30-year located experiment in Jinan of Shandong Province was selected and the results of soil nutrient and crop yield in 1984, 1987, 1988, 1989, 1990, 2001, 2005, 2006, 2007 and 2010 were measured and collected. In this study, five treatments： CK, NP, NK, PK and NPK of the located experiment were selected. [Result] The three types of soils in wheat yields decreased signifi- cantly in the first several years and in 2006. Wheat yields of the treatments with P fertilizers were obviously higher than those without P fertilizers; it was shown that phosphorus is the primary nutritional factor for high-yielding of wheat. The highest yield is from cinnamon soil, followed by that from brown soil, and the lowest pro- duction is from fluvo-aquic soil. Under the same fertilization, the influence of other factors on wheat yield of brown soil is the smallest, while cinnamon soil is vulnera- ble to the influence of external conditions, resulting in larger fluctuation of annual wheat yield. The alkali-hydro nitrogen contents of three kinds of soils first de- creased, then raised, and at last reduced apparently. Since 2007, the change of al- kali-hydro nitrogen content appeared rebounded. The available P contents of no- phosphorus treatments decreased over time while those of the treatments with P fertilizers increased at first, then decreased, and after that kept relatively stable. The available K contents of no K treatments decreased slowly. The treatments of PK and NK had higher available K content than NPK treatment. [Conclusion] Thus, it is an effective fertilization measure to improve the wheat yield by supplying reasonable phosphate fertilizer and nitrogen fertilizer and making up potassium fertilizer.

Effects of Long-term Located Fertilization on the Contents and Composition of Organic Matter in Paddy Soil

To reveal variation of organic matter content in red paddy soil, Through a 27 years-located fertilization experiment in red paddy soil, the content and composi- tion of organic matter in paddy soil were studied in this paper. The result showed that： the dynamics of soil organic matter of the different fertilization treatments showed significant differences, in the premise of equal nutrient （nitrogen and phos- phorus and potassium）, combining application of organic-inorganic was benefited for the accumulation of organic matter in paddy soil than without fertilizer treatment or chemical fertilizer treatment; the dynamics of soil humic acid, HA and FA of chemi- cal fertilizer only and Combining application of organic-inorganic treatments had basi- cally the same trend, But the contents of humic acid, HA and FA of combining ap- plication of organic-inorganic treatments had been higher than that without fertilizer and chemical fertilizer treatment. Moreover combining application of organic-inorganic treatments was benefited for improving the contents of HA and FA, but decreasing HA/FA ratio as an extension of time. Combining application of organic-inorganic was benefited for improving the contents ol readily oxidizable organic matter. And the contents of soil organic matter in long-term experiment and the contents of readily oxidizable O.M were highly significant positive correlation and the contents of soil total nitrogen, avail nitrogen and potassium were significant positive correlation; the contents of soil readily oxidizable O.M and the contents of soil total nitrogen, avail- able P and rice yield were significant positive correlation. Thereinto, the correlation （r=0.818 1 ） between the rice yield and soil readily oxidizable O.M was higher than the correlation （r=0.802 0） between the rice yield and soil organic matter. It showed the soil readily oxidized organic matter had greater contribution to the rice yield.

Geothermal extraction performance in fractured granite from Gonghe Basin,Qinghai province,China:Long-term injection and production experiment

The efficient exploitation of geothermal energy through enhanced geothermal systems(EGS)has been a relevant topic for hot dry rock(HDR)geothermal resources.When cryogenic fluid is injected into a thermal reservoir,improving heat exchange efficiency is key to achieving the optimal exploitation of HDR.In this paper,granite outcrops from Gonghe Basin were used as the testing sample.The natural fractures in the granite samples were relatively well developed.To simulate long-term injection and production from multi-wells in situ,physical ex-periments were performed in a newly-developed,in-house large-scale true triaxial experimental system.Geothermal extraction performance of an HDR was simulated for long-term injection and production operations.Simultaneously,the mode of one-injection and multiple-production wells was represented.In the paper,the ef-fects of the production-injection well spacing,the number of production wells and the injection rate on the production temperature and flow rate are discussed.The results show that,during long-term injection and pro-duction,there are two stages of production temperature variation,namely stabilization and attenuation.When the number of the production wells is increased,the heat extraction efficiency is accelerated.Moreover,competitive diversion of fluid among fractures occurred due to different conductivities.Furthermore,under different pro-duction modes,the production flow rate contributed differently to the heat extraction.Finally,the effect of the production-injection wells spacing on the heat exchange performance was analyzed;this is mainly reflected in the change of the effective heat exchange area between the rock and the injected fluid.The results emphasize the importance of designing an appropriate production mode and optimizing the injection-production parameters to ensure efficient HDR exploitation.

Experimental study on rheological deformation and stress properties of limestone

The systematic experiment regarding the general uniaxial compression test and the creep deformations of the typical limestones from the surrounding rock of the highway tunnels were made.The relationship between the axial stress and the delayed deformation steady value was obtained from the creep tests under low loading stresses.By the least square method,the parameters of Nishihara creep model were calculated from the creep curves.The results indicate that the strain change always lags behind the increase of stress,and the long-term strength of the limestone is about 80.6% of the stress at the volumetric strain reversal which is obtained from the conventional uniaxial compression test.

Flexural failure experiment on cracked PC simply supported box girders

Long-term load and flexural failure experiments are carried out on two prestressed concrete(PC) simply supported box girders. In the long-term load experiment, girder-1(G1) is in an elastic state, while girder-2(G2) is in a cracking state. To investigate the influence of cracking on the flexural behaviors of PC simply supported box beams, the experiment results are analyzed from many aspects, such as load–deflection, load–strain, and failure mode. Experiment results show the following: 1) the shrinkage and creep of concrete have considerable influences on the long-term deflection and strain of the two girders; 2) in the flexural failure experiment, the cracks and ultimate loads of the two girders are close. The rigidity degeneration of G2 is significantly faster than that of G1, and thus G2 shows nonlinear characteristics earlier; 3) to prove the validity and rationality of the current code, the cracking load and ultimate load of the two girders are calculated according to the current code.

QUICK ASSESSMENT METHODOLOGY FOR RELIABILITY OF SOLDER JOINTS IN BALL GRID ARRAY(BGA)ASSEMBLY——PART Ⅱ:RELIABILITY EXPERIMENT AND NUMERICAL SIMULATION

In the present study,a facility,i.e.,a mechanical deflection system (MDS),was established and applied to assess the long-term reliability of the solder joints in plastic ball grid array (BGA) assembly.It was found that the MDS not only quickly assesses the long-term reliability of solder joints within days,but can also mimic similar failure mechanisms in accelerated thermal cycling (ATC) tests. Based on the MDS and ATC reliability experiments,the acceleration factors (AF) were obtained for different reliability testing conditions.Furthermore,by using the creep constitutive relation and fatigue life model developed in part I,a numerical approach was established for the purpose of virtual life prediction of solder joints. The simulation results were found to be in good agreement with the test results from the MDS.As a result,a new reliability assessment methodology was established as an alternative to ATC for the evaluation of long-term reliability of plastic BGA assembly.

Effects of Long-term Located Fertilization on Evolution of Available Phosphorus and Phosphorus Pool in Shandong Fluvo-aquic Soil

This study was conducted to investigate the effects of long-term located fertilization on soil phosphorus,the changes of soil available phosphorus(OlsenP),the evolution of soil total phosphorus(TP)and the ratio change of Olsen-P to TP(PAC)by 33-year fertilization experiments in winter wheat-summer maize rotation system in Shandong fluvo-aquic soil.Eight treatments were designed as no fertilization(CK),nitrogen fertilizer(N),nitrogen and phosphate fertilizer(NP),nitrogen and potassium fertilizer(NK),phosphate and potassium fertilizer(PK),nitrogen-phosphate-potassium fertilizer(NPK),reduced NPK fertilizer(N(15)PK),and increased NPK fertilizer(N_(25)PK).Meanwhile,eight organic fertilizer-added treatments were designed based on the application of inorganic fertilizer the same as the above ones.The results showed that TP,Olsen-P and PAC of treatments added with organic fertilizer were higher than those without organic fertilizer,and those of the treatments applied with phosphate fertilizer were higher than those of no phosphate fertilizer.With the increase of years,soil P pool decreased due to crop absorption,nutrient loss and morphological transformation and other causes under the treatments of without and only phosphate fertilizer,while remained stable under the treatments added with organic fertilizer.The PAC values were generally lower in fluvo-aquic soil,and it could be improved by the application of organic fertilizer.On the whole,the application of chemical phosphate fertilizer combined with organic fertilizer could improve the phosphorus content in soil and ensure the supply of phosphorus nutrition.This study would provide scientific basis for fertilization management and soil fertility in fluvo-aquic soil.

Effects of Long-term Located Fertilization on the Physico-chemical Property of Soil Humus

A systematic study concerning the effects of a long-term stationary fertilization on content and property of soil humus in fluvo-aquic soil sampled from Malan Farm, Xinji City, Hebei, and arid red soil and paddy red soil sampled from the Institute of Red Soil, Jinxian County, Jiangxi was conducted. The results showed that long-term fertilization had effects not only on the content and composition of soil humus, but also on the physico-chemical property of humus. With applying organic manure or combined application of organic manure and chemical fertilizer, E4 and E6 values of humic acid decreased in fluvo-aquic soil and arid red soil, but increased in paddy red soil. In paddy red soil, E4 and E6 values of humic acid increased also with a single application of chemical fertilizer, but E4 and E6 values had less change of humic acid in fluvo-aquic soil and arid red soil. The effects on the visible spectroscopic property of f ulvic acid were different from that of humic acid. Long-term application of organic manure or combined application of organic manure and chemical fertilizer could increase E4 and E6 values of f ulvic acid in three types of soil. Single application of chemical fertilizer had less effect on the E4 and E6. Long-term fertilization could also influence the ultraviolet spectroscopic property of humus. With a single application of organic manure or combined application of organic manure and chemical fertilizer, the ultraviolet absorbance of humic acid and f ulvic acid increased in the three types of soil. But this effect was obvious only in short wave length, and the effect could decrease if the wave length increased. With a single application of chemical fertilizer the ultraviolet absorbance of fulvic acid could increase, but it of humic acid increased only in fluvo-aquic soil. Long-term application of organic manure or combined application of organic manure and chemical fertilizer could increase the content of total acidic groups, carboxy groups and phenolic hydroxy groups of humic acid and fuvic acid in the three types of soil. Single application of chemical fertilizer had less effect on the content of total acidic groups, carboxy groups and phenolic hydroxy groups of humic acid and fuvic acid in the three types of soil.

Long-Term Survival in Traumatic Brain Injury and Near-Death Experience Increases Suicide Risks: A Personal Experience and Related Literature

Background: Traumatic brain injury (TBI) remains a cause of lifelong disability, death, and suicide worldwide. TBI-induced near-death experience (NDE) could increase suicide risks. Objective: We investigated TBI coupled with NDE and posttraumatic stress disorder (PTSD) as a possible indicator of suicide. Methods: A 17-year-old male who sustained an acute severe TBI in a traffic collision, was comatose 14 days, had an NDE awakening from the coma, and, years after rehabilitation, suffered PTSD, clinical depression, and survived a suicide attempt. This personal experience of a TBI-induced NDE and lingering PTSD was acquired directly from the patient by interview. We discuss his case while considering relevant literature. Results: Longitudinal data from 1961 to 2021 generated from the PubMed interface revealed 4056 TBI patients committed suicide. NDE was only reported in one of those cases and, although not a suicide, in the personal experience. Neuropsychological assessment at long-term follow-ups revealed few TBI patients exhibited normal mental/physical functions compared to the general population. Unfavorable GOS scores were risk predictors for neuropsychological/physical impairments later in life, with outcomes of depression, PTSD, poor QOL, and/or suicide. Conclusions: For TBI-NDE survivors, including those with PTSD, long-term periodic neuropsychological follow-ups and psychosocial support may help decrease suicide risks.

Effects of Long-term Fertilization on Fertility of Lateritic Red Loam Paddy

The change rules of the fertility of red soil paddy under the long-term different fertilization were investigated, and the reasonable fertilization mode to improve the fertility of red soil paddy was discussed. There were eight treatments in the experiment, which were CK （no fertilizer）, N1 （N of 60 kg/hm2）, N2 （N of 120 kg/hm2）, N1P1 （P2O5 of 30 kg/hm2）, N2P1 and N2P2 （P2O5 of 60 kg/hm2）, N2P2K1 （K2O of 45 kg/hm2） and N2P2K2 （K2O of 90 kg/hm2）. All treatments were applied with composted cow dung as the base fertilizer, and each season 50% of the straws were returned to the field. The content of organic matter, nitrogen, phosphorous and potassium in red soil paddy was observed continuously for ten years and their correlation was also analyzed. Under cow manure and straw return to field, organic matter content of different treatments was positively correlated to year. After ten years, organic matter content of surface soil rose by 2.5 g/kg averagely with an annual increase of 0.25 g/kg. Total nitrogen content and organic matter content of different treatments presented similar variation trend. Total nitrogen content rose by 0.35 g/kg averagely with an annual increase of 0.035 g/kg. Among all the treatments, N2P2K1 and N2P2K2 showed the biggest increase, which went up by 0.052 and 0.48 g/kg, respectively. Phosphorous-free treatments （CK, N1, N2） had steady phosphorous content with irregular changes of different years. Total phosphorous content of phosphorous treatments increased year by year. Total phosphorous content of N1P1 and N2P1 rose by 0.008 g/kg every year. The increment range of total phosphorous content of N2P2, N2P2K1 and N2P2K2 was 0.012 -0.013 g/kg annually. Available phosphorous content varied vastly among different treatments. Available phosphorous content of organic fertilizer treatments basically remained stable with irregular changes of different years. Available phosphorous content of organic fertilizer with phosphate fertilizer treatments rose year by year. Available phosphorous content of N1P1 and N2P1 rose approximately by 0.8 mg/kg. Available phosphorous content of N2P2, N2P2K1 and N2P2K2 rose approximately by 1.4 -1.6 mg/kg annually. Potassium fertilizer amount greatly affected total potassium content. Total potassium content of no-potassium treatments （CK, N1, N2, N1P1, N2P1 and N2P2） remained the same. Total potassium content of N2P2K markedly increased year by year, which was 0.014 g/kg annually. Rapid available potassium content of no-potassium treatments （CK, N1, N2, N1P1, N2P1 and N2P2） showed a decreasing trend. With phosphate fertilizer, rapid available potassium content of N2P2K1 and N2P2K2 remained the same or increased year by year. The change trend of slow available potassium content and rapid available potassium content resembled. Rational allocation of organic fertilizer, nitrogenous fertilizer, phosphate fertilizer and potassium fertilizer can significantly improve soil fertility and economic benefits. Balanced fertilization is an effective measure for soil fertility improvement as it＇s shown that nutrients of surface soil accumulate annually.

31年长期施肥对潮土中微量元素演变及小麦微量元素吸收的影响

【目的】在华北平原典型潮土区,研究长期不同施肥措施对土壤全量与有效态铁、锰、锌、铜含量,以及小麦微量元素吸收的影响,为实现农田地力提升与作物高产优质提供理论依据。【方法】长期定位施肥试验位于河南省郑州市,始于1990年,已连续进行了31年。种植制度为冬小麦-夏玉米轮作。选取不施肥(CK),氮钾化肥(NK),氮磷钾化肥(NPK),氮磷钾化肥+秸秆还田(NPKS),氮磷钾化肥+有机肥(NPKM)5种施肥处理,分析每年土壤样品中全量与有效态铁、锰、锌、铜含量,以及作物秸秆与籽粒中相应微量元素含量。【结果】连续施肥31年后,各施肥处理土壤全量铁、锰含量与试验前无显著差异,全量锌、铜含量较试验前显著增加;NPKM处理土壤全量铁、锰、锌、铜含量均高于其它施肥处理。与CK相比,NPKM、NPKS与NPK处理显著提高了土壤有机质含量与阳离子交换量,降低了土壤pH值,有利于土壤中微量元素向有效态转化。NPKM与NPKS处理下土壤有效态铁、锰、锌含量显著高于其它施肥处理。NPK处理下土壤有效铁含量分别比CK和NK处理提高52%与49%;有效锰含量分别比CK和NK处理提高39%与11%。NPKM、NPKS与NPK处理下小麦地上部铁、锰、锌、铜吸收量与各微量元素收获指数显著高于CK与NK处理。但增产对籽粒中微量元素的稀释效应导致NPK、NPKS与NPKM处理下籽粒微量元素含量显著降低,其中铁、锌含量分别为推荐量下限的71%~74%、60%~63%。【结论】化肥与秸秆或有机肥配施有利于提高土壤微量元素的有效性。土壤全量与有效态微量元素含量的提高可促进小麦对微量元素的吸收,但增产对小麦籽粒中微量元素的稀释效应导致小麦籽粒中的铁、锌含量显著低于推荐量的下限。因此,在培肥潮土地力、提高作物产量的同时,也要考虑优化施肥策略或筛选适宜品种,以提高小麦籽粒中铁、锌含量,消除铁、锌元素缺乏对人体健康的不利影响。

狭窄库区滑坡涌浪特征分析及工程影响模型试验研究

为研究狭窄库区不同位置、体积滑坡涌浪对浪高及工程安全的影响,特以羊曲水电站库区H1滑坡体和1#变形体为例,建立1∶200的水工物理模型,研究失稳物质在体积100万、200万及500万m^(3)时产生的库区涌浪特征,进一步分析不同工况涌浪对特大桥及坝体稳定性的影响。结果表明:库区滑坡涌浪波类型为线性波,滑坡发生地和建筑物前的首浪高度均和失稳物质体积成正比;滑坡位置对工程的危害不一定和距离成反比,还和滑坡所处的水域条件相关;H1滑坡体或者1#变形体失稳产生的涌浪对特大桥无影响,但H1滑坡体体积大于200万m^(3)或1#变形体体积大于500万m^(3)时,会在溢洪道处漫坝。研究结果可为羊曲水电站库区滑坡涌浪灾害预防及应急调控措施制定提供参考。

高速公路隧道入口段障碍物视认距离实验研究

为研究障碍物视认距离受车速与布置距离的影响,招募了6位参与者在60、80、100 km/h三个速度水平下进行高速公路隧道实车实验。结果发现,参与者对障碍物的视认距离随着速度的增加而显著减小,在三个速度水平下,视认距离与障碍物布置的位置之间呈现V形变化趋势,最短视认距离出现在障碍物离洞口约60~80 m,其值低于或远低于该设计速度下的停车视距要求。偏相关性分析显示,运行速度、障碍物位置与距洞口70 m轴线相对距离这两个指标与障碍物视认距离呈现显著的正相关性。研究成果对当前我国高速公路隧道入口段的照明过渡设计提出更高要求。

张国梁表里分治新冠病毒感染恢复期咳嗽经验

[目的]介绍名中医张国梁应用表里分治法治疗新冠病毒感染恢复期咳嗽的临床经验。[方法]基于历代医家对疫病、咳嗽的相关论述,以及张师亲自诊治300余例新冠患者的经验,阐述张师对新冠病毒感染恢复期咳嗽病因病机的认识,总结其应用表里分治法治疗新冠病毒感染恢复期咳嗽的经验,并解读典型案例。[结果]张师认为,治疗新冠病毒感染恢复期咳嗽应当从病位着手,病位在鼻、咽部,采用表治法,重在宣肺化痰、疏风止咳,临床常用半夏厚朴汤、止嗽散合方随证加减。病位在气管、肺部,采用里治法,痰浊(痰热)蕴肺型重在清肺化痰、止咳平喘,临床多采用麻杏石甘汤、千金苇茎汤、葶苈大枣泻肺汤合方随证加减;气阴两虚型宜清肺化痰、益气养阴,一般采用竹叶石膏汤、生脉饮合方加减。文中所附医案属于风痰恋咽证型,张师先治以宣肺化痰、疏风止咳,后治以健脾益气、燥湿化痰,终获良效。[结论]张师应用表里分治法治疗新冠病毒感染恢复期咳嗽,见解独到,其临证经验值得学习和推广。