Derivation of energy-based base shear force coefficient considering hysteretic behavior and P-delta effects

A modified energy-balance equation accounting for P-delta effects and hysteretic behavior of reinforced concrete members is derived. Reduced hysteretic properties of structural components due to combined stiffness and strength degradation and pinching effects, and hysteretic damping are taken into account in a simple manner by utilizing plastic energy and seismic input energy modification factors. Having a pre-selected yield mechanism, energy balance of structure in inelastic range is considered. P-delta effects are included in derived equation by adding the external work of gravity loads to the work of equivalent inertia forces and equating the total external work to the modified plastic energy. Earthquake energy input to multi degree of freedom（MDOF） system is approximated by using the modal energy-decomposition. Energybased base shear coefficients are verified by means of both pushover analysis and nonlinear time history（NLTH） analysis of several RC frames having different number of stories. NLTH analyses of frames are performed by using the time histories of ten scaled ground motions compatible with elastic design acceleration spectrum and fulfilling duration/amplitude related requirements of Turkish Seismic Design Code. The observed correlation between energy-based base shear force coefficients and the average base shear force coefficients of NLTH analyses provides a reasonable confidence in estimation of nonlinear base shear force capacity of frames by using the derived equation.

Seminal characteristics and sexual behavior in men of different age groups： is there an aging effect？

Aim： To assess the seminal characteristics as well as the sexual behavior of men of various age groups to establish the presence of an aging effect on those characteristics. Methods： Semen samples were collected from men （n = 792） undergoing in vitro fertilization or intrauterine insemination in cases of female factor infertility only. Samples were collected using a seminal collection device at intercourse and evaluated manually according to World Health Organization （WHO） standards. Men were divided into four groups according to their ages： （i） 20-30, （ii） 31-40, （iii） 41-50 and （iv） 51-60 years, and their seminal characteristics and responses to a sexual behavior questionnaire were compared. Results： The data showed statistically significant differences in the seminal characteristics tested, most notably in the sperm concentration, motility, grade of motility, hypo-osmotic swelling and normal sperm morphology. Furthermore, the decline in normal sperm morphology with age was more pronounced when using strict criteria rather than WHO standards. There were also differences in total sperm count, total motile sperm and total functional sperm fraction （assessed by both WHO and strict criteria）. Significant differences were also observed in the sexual behavior patterns in older men in terms of the number of years they have been trying to conceive, sexual frequency and sexual satisfaction. Conclusion： The data clearly illustrate an aging effect on semen characteristics and sexual behavior in men as they age. It is suggested that the aging effect be taken into consideration when proposing normal standard values for semen characteristics in routine semen analysis as outlined by WHO standards.

Cognitive and Behavioral Effects of Participatory Sex Education on the Dual Prevention of STI/HIV/AIDS and Unwanted Pregnancies among Adolescents in Kinshasa High Schools, DR Congo

Context: With the view to reorient both STI/HIV/AIDS prevention and adolescents pregnancies, this research study aims at evaluating cognitive and behavioral acquisitions, as well as the process of interactive sex education participatory approach among adolescents in Kinshasa high schools. Methods: Based on a “pre and post” virtually experimental design, two crosswise surveys were conducted in Kinshasa, for six months in 2011-2012 on 484 high school students (pre-survey) and on 441 high school students (post-survey), whose age range from 14 - 19 years including both sexes. Two participatory educational talks (PET) “A” and “B”, covered weekly in two different schools, were compared to a control group school. The PET “A” consisted of interactive interpersonal communication sessions given by an external expert as a substitute for the life education course in one school. The PET “B” carried out in another school, included more educational talk sessions, led by the external expert and supplemented by a close follow-up of teenagers divided into small groups of 10 participants. The subjects’ assessment was based on their knowledge, attitudes and practices relating to STI/HIV/AIDS dual prevention as well as to unwanted pregnancies. Results: The subjects involved in the PET “B” displayed a better/higher performance based on their knowledge, attitudes and practices related to STI/HIV/AIDS dual prevention and unwanted pregnancies. Broadly speaking, knowledge has been improved 6 times with the PET “B” (OR = 6, 10, IC 95%) (3.24 - 11.9), and 3 times with the PET “A” (OR = 3, 45, IC 95%) (1.79 - 6.81), compared to control school. Similarly, findings on subjects’ attitudes show an improvement rated 12 times with the PET”B” (OR = 11, 99, IC 95%) (5.67 - 27.38) and 5 times for the PET “A” (OR = 5.51, IC 95%) (2.54 - 12.87). As far as the subjects’ practices are concerned, an improvement of 6 more times of protected sexual intercourses with the PET “B” compared with the control school group (OR = 6, 52, IC 95%) (3.60 - 12.0). The process assessment records a spontaneous involvement of schools enhanced by the positive contribution of Life Education and Biology teachers;add a massive participation of adolescents who requested permanent PET program. Conclusion: The results of this study suggest that school sexual education programs can be improved to increase the quality of apprenticeship. The use of interactive methods and the consideration of the adolescents’ specific needs that take into account the gender approach may bring about beneficial advantages on both educational outcomes and reproductive health of adolescents.

THE EFFECT OF RARE EARTH ELEMENTS ON THE SOLIDIFICATION BEHAVIOR OF Al-Mg ALLOYS

The effect of rare earth element on the solidification behavior of Al-Mg alloy was investigated in a directional solidification apparatus.It was found that during the solidification process.the rare earth element segregated in the liquid at sold-liquid interface,changed the solidification morphology and reduced the secondary arm spacing markedly.

Effects of microrolling parameters on the microstructure and deformation behavior of pure copper

Microrolling experiments and uniaxial tensile tests of pure copper under different annealing conditions were carried out in this paper. The effects of grain size and reduction on non-uniform deformation, edge cracking, and microstructure were studied. The experimen- tal results showed that the side deformation became more non-uniform, resulting in substantial edge bulge, and the uneven spread increased with increasing grain size and reduction level. When the reduction level reached 80% and the grain size was 65 μm, slight edge cracks occurred. When the grain size was 200 μm, the edge cracks became wider and deeper. No edge cracks occurred when the grain size was 200 μm and the reduction level was less than 60%; edge cracks occurred when the reduction level was increased to 80%. As the reduction level increased, the grains were gradually elongated and appeared as a sheet-like structure along the rolling direction; a fine lamellar structure was obtained when the grain size was 20 lam and the reduction level was less than 60%.

Effects on the Behavior and Neuroimmunity of Pulsed Microwaves with Different Peak Densities

Pulsed microwaves are widely used inradar,navigation, and communication. The average power density is low at narrow pulse widths or large pulse intervals,but pulsed microwaves at certain peak densities exert numerous biological effects, including

Effect of Optical Microcavity on Absorption Behavior of Homo-Tandem Organic Solar Cells

The optical microcavity effect of the homo-tandem solar cells is explored utilizing the transfer matrix method. Ultrathin silver can reduce the deadzone effect compared with graphene and PH1000, and leads to a factor of 1.07 enhancement for an electrical field in a metal microcavity. The enhancement is considered to be the fact that strong exciton-photon coupling occurs in the microcavity due to ultrathin Ag. On the basis of the optical enhancement effect, optical behaviors are manipulated by varying the microcavity length. It is confirmed that ultrathin silver can serve as an ideal interconnection layer as the active layer is ～ 150nm thick and the thickness ratio between front and rear active layers lies between 1：1 and 1：2.

土壤中微塑料:类型、载体效应、迁移行为和潜在风险综述

微塑料(microplastics,MPs)作为一种新兴污染物,广泛存在于土壤中,并不断迁移转化,对土壤生态系统和生物多样性产生潜在风险。为了全面评估土壤MPs的环境风险,加强MPs污染的风险管控,讨论了土壤环境中MPs的类型,系统阐述了土壤MPs的载体效应和迁移行为,并从微生物、植物、动物以及人类四个方面综述了土壤MPs的潜在风险。土壤中MPs并不是单独存在的,MPs的潜在风险一方面来自其本身(颗粒和添加剂)的生物毒性,另一方面是其对共存污染物(有机污染物、重金属和致病菌等)的载体效应。在非生物(淋溶、重力)和生物等作用下,土壤中的MPs时刻都在经历着复杂的迁移过程,从而加剧了其对土壤生态系统的影响。由于粒径小,MPs很容易进入食物链并层层传递,从而对不同营养级生物的正常生理活动产生不利影响,包括影响土壤动植物的新陈代谢,生长,发育和繁殖。此外,MPs不仅在环境中存在,而且也在人体中被发现。MPs可通过饮食、呼吸或皮肤接触等途径进入人体,从而对人体可能产生一系列不良反应。虽然目前仍没有足够的证据证明MPs对人体的直接危害,但其潜在风险仍不容忽视。探讨了土壤MPs污染治理的策略,并对未来土壤微塑料污染的研究方向和重点进行了展望。研究将有助于加深人们对土壤微塑料污染的认识,并为更好地开展微塑料的毒理效应研究和风险评估提供科学线索和理论参考。

EFFECTS OF ROCK BEHAVIOR ON DEFORMATION AND CIVIL ENGINEERING

Rock behavior is usually run into in study on geological deformation, teetono-mineralization and civil engineering.Rock behavior contains its texture,structure and composition,rock property,and its occurrence background or situation. That is to say, temperature, compression,content of water and other liquid in rocks, boundary condition of rock block,straining rate etc.,which are closely related to the depth of occurrence of rock, influence on the rock behavior and deformation effects.

Effects of Ta Addition on Microstructure and Transformation Behavior of Ni-Ti Alloys

The effect of adding Ta on the changes of microstructure and Ms temperature of a dualphase shape memory alloy with compositions of (Ni51 Ti49)1 -x.Tax. and Ni50-Ti50 -g.Ta.g were systematically studied. An optical microscope, SEM, X-ray diffraction and DSC were utilized in this work. The evolution of the microstructure as a function of Ta content was characterized. The variation of the Ni/Ti ratio in the NiTi phase plays an important role in the change of the Ms temperatures due to the addition of Ta. A pseudobinary NiTi-Ta phase diagram was proposed based on these results.

ON THE DRIVING BEHAVIOR，VARIABLE－DIAMETEREFFECT AND BEAKING CAPACITY OF DRIVENCAST－IN－SITU PILE WITHFLAT

ＯＮＴＨＥＤＲＩＶＩＮＧＢＥＨＡＶＩＯＲ，ＶＡＲＩＡＢＬＥ－ＤＩＡＭＥＴＥＲＥＦＦＥＣＴＡＮＤＢＥＡＫＩＮＧＣＡＰＡＣＩＴＹＯＦＤＫＩＶＥＮＣＡＳＴ－ＩＮ－ＳＩＴＵＰＩＬＥＷＩＴＨＦＬＡＴＯＶＥＲＳＩＺＥＴＩＰＳｈｉＰｅｉｄｏｎｇ，ＦｕＺｈｅｎｑｉｕ...

Relationship between biological features and the SMVS's inhibitory effect on mating behavior of Nilaparvata lugens (Stal)

Our previous studies revealed that second malevibration signal (SMVS) restrained the matingbehavior of N. lugens, the influences of threebiological features (density, age, and wingform) on SMVS’s inhibitory effect were hereinstudied by playing back its record. The dura-tion of playback was 4 h. Except otherwisestatement, N. lugens tested were virginmacropterous males and females aged 4-6 d af-ter emergence, and the density was 5 pairs (5females and 5 males) of N. lugens per cage (4cm in diameter and 8 cm in height). The in-hibitory effect of SMVS was evaluated usingmating rate (i. e. the rate of females withspermatophore). The results were as follows:

钢筋及BFRP筋混凝土深受弯构件受剪性能及尺寸效应对比分析:试验研究

文章旨在研究并对比钢筋及BFRP筋(玄武岩纤维增强筋)混凝土深受弯构件受剪性能及尺寸效应的异同,对4根钢筋混凝土深受弯构件及4根BFRP筋混凝土深受弯构件(梁高为300~1200mm)进行了剪切破坏试验。对比分析了荷载-位移曲线、斜裂缝宽度、混凝土应变、纵筋应变及腹筋应变随结构尺寸变化的发展趋势。揭示了钢筋及BFRP筋混凝土深受弯构件抗剪强度尺寸效应规律,并分析了设计规范和计算方法的适用性。研究表明:(1)BFRP筋混凝土深受弯构件的极限荷载约为钢筋混凝土深受弯构件的0.3~0.5倍,而挠度约为钢筋混凝土深受弯构件的1.4~1.7倍;(2)梁高从300mm增至1200mm时(试验梁的水平及竖向腹筋率均为0.51%),钢筋混凝土深受弯构件的名义极限抗剪强度下降34.0%,而BFRP筋混凝土深受弯构件下降45.7%;(3)对于大尺寸构件的抗剪承载力,设计规范的计算结果安全储备不足,未能合理考虑尺寸效应;(4)提出的尺寸效应理论公式可以定量描述结构尺寸对钢筋及BFRP筋混凝土深受弯构件名义极限抗剪强度的影响。

许氏平鲉幼鱼对人工鱼礁模型不同阴影情况的行为响应

阴影效应是影响人工鱼礁诱集效果的主要因素之一,为研究许氏平鲉(Sebastes schlegelii)对人工鱼礁不同阴影情况的行为响应,采用室内模拟实验方法,在实验水槽顶部固定光源,共设计3组实验:A组实验探究不同阴影面积的鱼礁模型对实验鱼的诱集效果;B组实验探究不放置鱼礁模型、悬挂不同开孔率顶板对实验鱼的诱集效果;C组实验探究阴影面积相同但开孔数量不同的鱼礁模型对实验鱼的诱集效果;对照组实验水槽中不放置鱼礁模型、不悬挂顶板。观察并记录许氏平鲉幼鱼(体长(5.06±0.09)cm,体质量(3.22±0.16)g)在水槽中的行为与分布特征。研究表明:3个实验组中许氏平鲉在鱼礁放置区域的出现率均显著高于对照组和其他区域;A组实验中,许氏平鲉在鱼礁放置区的平均出现率随着鱼礁阴影面积的增大而上升;B组实验中,许氏平鲉在顶板放置区的平均出现率显著高于对照组,但不同水平组之间差异不显著;C组实验中,开孔数为1时许氏平鲉在鱼礁放置区的平均出现率与开孔数为9时相近且高于开孔数为4和6时。研究结果表明,阴影面积越大的人工鱼礁对许氏平鲉的诱集效果越好,阴影面积相同时开孔数较多的人工鱼礁能够在提供良好庇护所的同时保证诱集效果。

Pressure effect on magnetic phase transition and spin-glass-like behavior of GdCo_2B_2

We systematically investigate the effect of pressure on the magnetic properties of GdCo2B2 on the basis of alternating current（AC） susceptibility,AC heat capacity and electrical resistivity measurements under pressures up to 2.2 GPa.A detailed magnetic phase diagram under pressure is determined.GdCo2B2 exhibits three anomalies that apparently reflect magnetic phase transitions,respectively,at temperatures TC= 20.5 K,T1= 18.0 K and TN= 11.5 K under ambient pressure.Under pressures up to 2.2 GPa,these anomalies are observed to slightly increase at TCand T1,and they coincide with each other above 1.6 GPa.Conversely,they decrease at TN and disappear under pressures higher than 1.4 GPa.The results indicate that the low-temperature magnetic phases can be easily suppressed by pressure.Moreover,the spin-glass-like behavior of GdCo2B2 is examined in terms of magnetization,aging effect and frequency dependence of AC susceptibility.A separation between the zero-field-cooled（ZFC） and field-cooled（FC） magnetization curves becomes evident at a low magnetic field of 0.001 T.A long-time relaxation behavior is observed at 4 K.The freezing temperature Tfincreases with frequency increasing.

信息技术环境下大学生高效学习行为分析与对策

信息技术环境下的学习模式具有开放性、交互性、虚拟性、智能性和便捷性等优势,在“互联网+教育”和疫情常态化的大背景下,在线教育成为高校学生学习的重要方式。同时,由于在线学习的时空阻隔问题,学生缺少直接有效的监督、课堂互动交流不足、且容易受到外界环境的干扰,上述因素不同程度地影响教学效果。该文在“高效学习”的定义框架上,深入探讨学生在线学习行为的内外在特征和运行机制,梳理高效学习行为影响因素,并从“学校-教师-学生”和“课前-课中-课后”二个维度六个方面探讨高效提升学生学习效果的应对措施。

Random crystal field effect on hysteresis loops and compensation behavior of mixed spin-(1,3/2) Ising system

Magnetic hysteresis and compensation behavior of a mixed spin-（1, 3/2） Ising model on a square lattice are investigated in the framework of effective field theory based on a probability distribution technique. The effect of random crystal field, ferromagnetic and ferrimagnetic exchange interaction on hysteresis loops and compensation phenomenon are discussed. A number of characteristic phenomena have been reported such as the observation of triple hysteresis loops at low temperatures and for negative values of random crystal field. Critical and double compensation temperatures have been also found. The obtained results are also compared to some previous works.

基于动机行为转化的护理措施在妊娠期糖尿病患者中的应用分析

目的分析基于动机行为转化的护理措施在妊娠期糖尿病(Gestational Diabetes Mellitus,GDM)患者中的应用效果。方法选取2022年12月-2023年11月泰安市中心医院收治的104例GDM患者为研究对象,按随机数表法分为两组。对照组(52例)采取常规护理,研究组(52例)在对照组基础上采用基于动机行为转化的护理措施。对比两组血糖指标、自我护理能力量表(Exercise of Self-care Agency Scale,ESCA)评分及护理满意度。结果干预后,研究组餐后2 h血糖、空腹血糖水平低于对照组,差异有统计学意义(P均<0.05)。干预后,与对照组相比,研究组ESCA评分更高,差异有统计学意义(P<0.05)。研究组护理总满意度高于对照组,差异有统计学意义(P<0.05)。结论基于动机行为转化的护理措施在GDM患者中具有较为理想的应用效果,可以提高其自我护理能力与护理满意度,保障血糖控制效果。