Application and Validation of a Multi-block Constitutive Model at Landslides of the Wenchuan Earthquake

A multi-block model and a corresponding computer program have been developed which predict the kinematics of landslides.Furthermore,a unique event for studying different models simulating the triggering and movement of landslides is the 2008Wenchuan earthquake in the mountainous region in Sichuan Province of China,which caused a large number of rapid landslides.The purpose of the paper is two-fold:(a)to propose and incorporate into the multi-block model constitutive relations predicting soil response along slip surfaces,and(b)to apply the multi-block model with the constitutive relations at landslides triggered by the Wenchuan earthquake.The proposed constitutive equations predict the shape of the shear stress-displacement response measured in ring shear tests.In the application,four landslides caused by the Wenchuan earthquake were considered.Only in one of these landslides the shear resistance-displacement response along the slip surface has been measured in laboratory tests.At this landslide,the triggering and movement of the landslide was predicted.In the other landslides,back analyses were performed and it was observed that the multi-block model predicted reasonably well the final configuration of all slides.In addition,as the measured and back-estimated total friction angle of all landslides was less than 180,and the materials along the slip surface were sandy,it is inferred that some,or all of the slip surface during these slides was sheared in an undrained manner and excess pore pressures generated during sliding played a key role in the triggering and movement of these landslides.Concluding,the paper(A)proposed and validated a multi-block constitutive model which can be applied to predict the triggering and movement of earthquake-induced slides and(B)by analyzing four landslides of the 2008 Wenchuan earthquake,it concludes that some,or all of the slip surface during these slides,was sheared in an undrained manner and excess pore pressures generated during sliding played a key role in the triggering and movement of these landslides.     

Superhydrophobic-superhydrophilic binary micropatterns by localized thermal treatment of polyhedral oligomeric silsesquioxane (POSS)-silica films

Surfaces patterned with alternating (binary) superhydrophobic-superhydrophilic regions can be found naturally, offering a bio-inspired template for efficient fluid collection and management technologies. We describe a simple wet-processing, thermal treatment method to produce such patterns, starting with inherently superhydrophobic polysilsesquioxane-silica composite coatings prepared by spray casting nanoparticle dispersions. Such coatings become superhydrophilic after localized thermal treatment by means of laser irradiation or open-air flame exposure. When laser processed, the films are patternable down to ～100 μm scales. The dispersions consist of hydrophobic fumed silica (HFS) and methylsilsesquioxane resin, which are dispersed in isopropanol and deposited onto various substrates (glass, quartz, aluminum, copper, and stainless steel). The coatings are characterized by advancing, receding, and sessile contact angle measurements before and after thermal treatment to delineate the effects of HFS filler concentration and thermal treatment on coating wettability. SEM, XPS and TGA measurements reveal the effects of thermal treatment on surface chemistry and texture. The thermally induced wettability shift from superhydrophobic to superhydrophilic is interpreted with the Cassie-Baxter wetting theory. Several micropatterned wettability surfaces demonstrate potential in pool boiling heat transfer enhancement, capillarity-driven liquid transport in open surface-tension-confined channels (e.g., lab-on-a-chip), and select surface coating applications relying on wettability gradients. Advantages of the present approach include the inherent stability and inertness of the organosilane-based coatings, which can be applied on many types of surfaces (glass, metals, etc.) with ease. The present method is also scalable to large areas, thus being attractive for industrial coating applications.     

Association of psychology postdoctoral and internship centers' guidelines and the internship selection process: A survey of applicants and academic and internship training directors.

Although the Association of Psychology Postdoctoral and Internship Centers (APPIC) established guidelines for internship offers and acceptances, the internship selection process has been viewed as stressful by many of its participants. The present study explored participants' experiences with the selection process to understand how certain behaviors may contribute to selection difficulties. Surveys were mailed to internship applicants, academic training directors, and internship training directors who participated in the 1994–1995 selection process. Results revealed some significant differences among these respondents with respect to their perceptions of potential internship selection behaviors. In addition, 40% of the internship applicants perceived that violations of the APPIC guidelines had occurred during the selection process. Recommendations for addressing internship selection issues are presented. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Examining the Cultural Adjustment Experiences of African International College Students: A Qualitative Analysis.

The authors examined the cultural adjustment experiences of 12 Kenyan, Nigerian, and Ghanaian international college students through semistructured interviews. Using consensual qualitative research methodology (C. E. Hill, B. J. Thompson, & E. N. Williams, 1997), 7 primary domains or themes related to these students' cultural adjustment experiences were identified, including (a) presojourn perceptions of the United States, (b) postsojourn perceptions of the United States, (c) cultural adjustment problems in the United States, (d) responses to prejudicial or discriminatory treatment, (e) family and friendship networks, (f) strategies for coping with cultural adjustment problems, and (g) openness to seeking counseling to address cultural adjustment problems. Implications of the findings are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

私有资本和公有资本--合作的时间到了吗?

1前言康斯坦丁·欧刚必依分析了已被发现的吸引私营参与者的成功与失败的原因后,主张建立一种新的模式,在这种模式下,公私合作共同投资电力。据估计,西非有20%的人口已用上电,最低的是尼日尔和几内亚比绍,只有4%人口能用上电。特别指出的是,西非的农村电气化程度非常低,只有1%~2%的人口用上电。尽管西非拥有巨大的未开发资源(比如尼日尔和伏尔特河,以及几内亚湾和周边地区储藏的原油和天然气),但是,西非仍然是世界上最低发电率和最低电力消费水平的地区。整个地区的电力消费大约是32TW·h:其中尼日利亚(14·6TW·h,45·8%),加纳(8·8TW·…     

Development and preliminary validation of the Cultural Values Conflict Scale for South Asian women.

This article describes the development and validation of the Cultural Values Conflict Scale (CVCS) for South Asian women in the United States. Three hundred nineteen participants were administered the CVCS. Exploratory factor analysis supported a 2-factor model of cultural value conflict, namely intimate relations and sex role expectations. Results indicated that the internal consistency and test-retest reliabilities were adequate. Discriminant validity was demonstrated by differences shown between 1st and 2nd-generation South Asian women. Convergent validity was demonstrated by a positive relationship between the CVCS and measures of anxiety and cultural adjustment difficulties. Finally, it appears that social desirability plays a role in the self-representation of this group of South Asian women. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A geomorphic monitoring and adaptive assessment framework to assess the effect of lowland floodplain river restoration on channel–floodplain sediment continuity

The state of the science of lowland river floodplain restoration reflects the relatively new and experimental nature of large river floodplain rehabilitation efforts. Based on results of a case study of floodplain restoration at the lowland Cosumnes River, California, we present a geomorphic monitoring and adaptive assessment framework that addresses the need to inform and utilize scientific knowledge in lowland floodplain river restoration activities. Highlighting hydrogeomorphic processes that lead to habitat creation, we identify a discharge threshold for connectivity and sediment transfer from the channel to the floodplain and integrate discharge magnitude and duration to quantify a threshold to aid determination of when geomorphic monitoring is warranted. Using floodplain sand deposition volume in splay complexes as one indicator of dynamic floodplain habitat, we develop a model to aid prediction of the sand deposition volume as an assessment tool to use to analyze future monitoring data. Because geomorphic processes that form the physical structure of a habitat are dynamic, and because the most successful restoration projects accommodate this fundamental characteristic of ecosystems, monitoring designs must both identify trends and be adapted iteratively so that relevant features continue to be measured. Thus, in this paper, adaptive assessment is defined as the modification of monitoring and analysis methods as a dynamic system evolves following restoration activities. The adaptive monitoring and assessment methods proposed facilitate long‐term measurements of channel–floodplain sediment transfer, and changes in sediment storage and morphology unique to lowland river–floodplain interactions and the habitat that these physical processes support. The adaptive assessment framework should be integrated with biological and chemical elements of an interdisciplinary ecosystem monitoring program to answer research hypotheses and to advance restoration science in lowland floodplain river systems. Copyright © 2005 John Wiley & Sons, Ltd.     

Effect of ECR plasma on the luminescence efficiency of InGaAs and InP

InGaAs and InP exposed to N₂ or Ar ECR plasmas show reduced photoluminescence intensity. The extent of the degradation depends on both the microwave power level and any additional r.f. power applied to increase the energy of ions in the discharge. Annealing at 200°C restores approx. one-third of the initial luminescence efficiency in both materials, but HF removal of the native oxide increases the PL intensity to 80% in InGaAs and 40% in InP. The mechanism for the degraded optical output from these materials is creation of both interface and bulk states. The latter are present to depths of ≥200 Å and are more prevalent in InP. Passivation of the surfaces using (NH₄)₂S treatment completely restores the PL intensity in InGaAs, but not in InP. ECR deposition of SiN_x shows excellent conformity around the gate contact of submicron high electron mobility transistors, and an absence of the rabbit-ears typically present with conventional PECVD.