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This article presents experimental data on the earth pressures that develop between mechanically stabilized earth (MSE) wall panels that are tied together in an unyielding condition. Prior to design and construction, an extensive literature review was conducted to ensure the MSE wall adhered to the local standard specifications for road and bridge construction, current design codes, and the construction sequencing specified by the wall panel manufacturer. The Strong Wall at the University of Florida's Structures and Materials Laboratory was utilized to construct a model full-scale MSE wall using inextensible reinforcement, with 140 locations continuously monitored. The MSE wall was divided into two different relative compaction zones, 95% and 103% of the reinforced soil's optimum dry density, to investigate a range of friction angles that can develop during conventional construction. To achieve the necessary aspect ratio of 0.3 specified by practitioners for use in real-world applications, a reaction frame was incrementally loaded on top of the reinforced backfill to simulate additional wall height and overburden stress. Earth pressure coefficients were found for each compacted soil lift and incremental load from the reaction frame for both states of soil density. A force equilibrium analysis was conducted to ensure all forces within the experimental setup were accounted for to validate the results. From the derived earth pressure coefficients, it was observed that earth pressures moved from a passive condition to an active or at-rest condition as the soil-height increased above each reinforcement level. It was concluded that increased lateral stress develops from the compaction effort in an unyielding condition, which is not accounted for using conventional MSE design methods. Consequently, an equation was developed that incorporates a variable friction angle (φ) based on the compaction effort for an unyielding condition that closely followed the trends of the measured results. [ABSTRACT FROM AUTHOR]

The focus of this research is the real-time assessment of drilled shaft capacity based on the unconfined compressive strength ([q.sub.u]) obtained from measuring while drilling (MWD). Measures of [q.sub.u], a function of rock strength commonly used in drilled shaft design, are provided through five monitored drilling parameters: torque, crowd, rotational speed, penetration rate, and bit diameter. Monitored shaft installations took place at three separate locations on drilled shafts, which were subsequently load tested. Using the [q.sub.u] values obtained from MWD, side shear was estimated in portions of each shaft where instrumented segments indicated the side shear was fully mobilized for direct comparison. To consider all of the current side shear equations used in Florida drilled shaft design, the estimation of tensile strength ([q.sub.t]) in real time was also needed. This led to a theoretical approach to establish the [q.sub.t]/[q.sub.u] relationship that was later verified empirically and provided new correlations between material and mechanical properties of Florida geomaterials. A comparative analysis indicated that the results from multiple established side shear equations, used with [q.sub.u] from MWD, align well with the results obtained from load testing. This suggests that estimating drilled shaft capacity from MWD is viable to reduce spatial uncertainty. Key words: drilled shaft, rock auger, measuring while drilling, Florida limestone, specific energy. L'objectif de cette etude est l'evaluation en temps reel de la capacite du puits fore base sur la resistance en compression simple ([q.sub.u]) obtenue a partir de la mesure en cours de forage (MWD). Les mesures de [q.sub.u], une fonction de la resistance de la roche communement utilisee dans la conception des puits fores, sont fournies par cinq parametres de forage surveilles: couple, foule, vitesse de rotation, vitesse de penetration et diametre du trepan. Des installations a puits controle ont eu lieu a trois endroits differents sur des puits fores qui ont ensuite ete soumis a des essais de charge. En utilisant les valeurs de [q.sub.u] obtenues a partir de MWD, le cisaillement lateral a ete estime dans des parties de chaque puits ou des segments instrumentes ont indique que le cisaillement lateral etait entierement mobilise pour une comparaison directe. Afin de prendre en compte toutes les equations de cisaillement lateral utilisees dans la conception des puits fores en Floride, l'estimation de la resistance a la traction ([q.sub.t]) en temps reel etait egalement necessaire. Cela a conduit a une approche theorique pour etablir la relation [q.sub.t]/[q.sub.u] qui a ensuite ete verifiee empiriquement et a fourni de nouvelles correlations entre les proprietes materielles et mecaniques des geomateriaux de la Floride. Une analyse comparative a indique que les resultats de plusieurs equations de cisaillement lateral etablies, utilisees avec [q.sub.u] de MWD, s'harmonisent bien avec les resultats obtenus a partir des essais de charge. Ceci suggere que l'estimation de la capacite de puits fore par MWD est viable pour reduire l'incertitude spatiale. Mots-cles: puits fore, tariere a roche, mesure en cours de forage, calcaire de Floride, energie specifique., Introduction This paper explores using measurements of unconfined compressive strength, obtained from measuring while drilling shafts, to estimate side shear capacity in real time. The research discussed is part of [...]

The Canadian Journal of Applied Linguistics has released its first regular issue of 2024, featuring six articles and two book reviews. The articles cover a range of topics, including reading development in young French learners, language support screening procedures, native speaker evaluations of second language learners, and the role of language educators. One article focuses on a study of phonological awareness intervention for English-speaking kindergarteners in a French immersion program, while another discusses a remedial program for prosodic skills in French-speaking students. Additionally, there are articles on screening-diagnostic assessments for college students, the comprehensibility of expressions by French second language learners, and the perspectives of educators in French immersion programs and multilingual pedagogy in an international school. The issue also includes book reviews and announces a future special issue on written corrective feedback. [Extracted from the article]

Background: Conceptual understanding is a prerequisite for engineering competence. Concept maps may be effective tools for assessing conceptual knowledge, yet further work is needed to examine scoring methods. Purpose: Our purpose was to evaluate the efficacy of three concept map scoring methods. Traditional scoring requires judges to count concept map components. Holistic scoring requires judges to analytically evaluate concept maps using a rubric. Categorical scoring requires judges to categorize concepts according to relevant categories before quantification of overall complexity. Design/Method: In this study, concept maps were collected from 72 undergraduates before and after a capstone design course. Judges analyzed the concept maps using three methods. Using statistical analyses, we examined the comparability, interrater reliability, and convergent/divergent validity of scoring methods. Results: While traditional scoring allowed judges to score concept maps relatively quickly, holistic scoring allowed judges to better capture changes in knowledge structure, because ranking of data was required without assuming hierarchical concept arrangement. Only categorical scoring provided insight into content and structure of student knowledge. For all methods, interrater reliability was acceptable, and convergent/divergent validity was established. Conclusions: Due to its applicability to concept maps of varying structures, holistic scoring is best if more than one judge is available; traditional scoring is appropriate if there are time constraints or if multiple methods are used. Categorical scoring has potential as a supplemental or stand-alone method, depending on the needs of the instructor or researcher.

The focus of this research is the real-time assessment of rock strength (unconfined compressive strength, [q.sub.u]) during drilled shaft installations in Florida limestone, where measures of rock strength are provided through five monitored drilling parameters: torque, crowd, rotational speed, penetration rate, and bit diameter. To complete the study, both a laboratory and field investigation were required. This paper covers drill rig instrumentation, measuring rock strength during field drilling, and the comparative analysis of rock strength with conventional methods. Real-time measurements were recorded for each drilling parameter and graphically displayed on an in-cab monitor and wirelessly transmitted to an external computer. Measures of rock strength were estimated using a laboratory-developed equation with the monitored drilling parameters for real-time field assessment. Measuring while drilling in the field took place at three separate locations where drilled shaft load testing occurred. Comparative analyses between the monitored shaft installations and core samples subjected to unconfined compression indicated the results aligned well when recoveries were good. As recoveries diminished, the mean strengths were comparable, but more variable. Key words: drilled shaft, measuring while drilling, construction monitoring, Florida, limestone. L'objectif de cette recherche est Revaluation en temps reel de la resistance de la roche (resistance a la compression non confinee, [q.sub.u]) pendant les installations de puits fores dans le calcaire de Floride; ou les mesures de la resistance de la roche sont fournies par cinq parametres de forage surveille : le couple, la pression verticale vers le bas, la vitesse de rotation, le taux de penetration et le diametre du trepan. Afin de completer la recherche, un essai en laboratoire et un essai sur le terrain ont ete necessaries. Ce document couvre l'instrumentation de l'appareil de forage, la mesure de la resistance de la roche pendant le forage sur le terrain et l'analyse comparative de la resistance de la roche avec les methodes conventionnelles. Des mesures en temps reel ont ete enregistrees pour chaque parametre de forage et affichees graphiquement sur un moniteur dans la cabine et transmises sans fil a un ordinateur externe. Les mesures de la resistance des roches ont ete estimees a l'aide d'une equation developpee en laboratoire avec les parametres de forage surveilles pour Revaluation en temps reel sur le terrain. La mesure en cours de forage sur le terrain a eu lieu a trois endroits differents ou des essais de charge des puits fores ont ete effectues. Des analyses comparatives entre les installations de puits controlees et les carottes de forage soumises a une compression non confinee ont indique que les resultats etaient bien alignes, lorsque les prelevements d'echantillons etaient bons. A mesure que les prelevements diminuaient, les forces moyennes etaient comparables, mais plus variables. [Traduit par la Redaction] Mots-cles: puits fores, mesure en cours de forage, surveillance de la construction, Floride, calcaire., Introduction Over the past few decades there has been an increase in the use of drilled shafts to support large structures in Florida. The shift from driven piles to drilled [...]

The concentrations of O3 and its precursors over North America are simulated for three summer months with a three-dimensional, continental-scale photochemical model using meteorological input from the Goddard Institute for Space Studies (GISS) general circulation model (GCM). The model has 4°×5° grid resolution and represents non linear chemistry in urban and industrial plumes with a subgrid nested scheme. Simulated median afternoon O3 concentrations at rural U.S. sites are within 5 ppb of observations in most cases, except in the south central United States where concentrations are overpredicted by 15–20 ppb. The model captures successfully the development of regional high-O3 episodes over the northeastern United States on the back side of weak, warm, stagnant anticyclones. Simulated concentrations of CO and nonmethane hydrocarbons are generally in good agreement with observations, concentrations of NOx are underpredicted by 10–30%, and concentrations of peroxyacylnitrates (PANs) are overpredicted by a factor of 2 to 3. The overprediction of PANs is attributed to flaws in the photochemical mechanism, including excessive production from oxidation of isoprene, and may also reflect an underestimate of PANs deposition. Subgrid nonlinear chemistry as captured by the nested plumes scheme decreases the net O3 production computed in the United States boundary layer by 8% on average.

The article discusses a case of a 74-year-old female with a gastric cardia submucosal tumour and a small hiatus hernia. The patient underwent laparoscopic enucleation of a leiomyoma with positive histological results. The importance of accurate histopathological diagnosis for submucosal lesions near the gastroesophageal junction is highlighted, along with the challenges in management and considerations for surgical approaches. The article emphasizes the need for precise diagnosis to determine the appropriate treatment and surgical techniques for submucosal tumours, such as gastrointestinal stromal tumours or leiomyomas. [Extracted from the article]