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In the present work, different algorithms and penalty methods for design optimization of mechanical elements and structures are applied. Seven robust optimization techniques and seven penalty methods are thoroughly investigated and implemented in MATLAB codes. In addition, different optimization models are compared using two benchmark problems, namely, the minimal cost design of a welded beam structure and the optimal buckling design of a functionally graded material column. A performance measure factor is defined to determine the best technique among the implemented optimization algorithms. The results are arranged and nested to make it easy for the reader to figure out each technique characteristics, and hence choose the suitable one for a specific design problem and/or application. Comprehensive computer experimentations were performed, and the best optimization techniques and models have been thoroughly demonstrated. The attained optimal solutions show that, in general, the hybrid algorithms worked better than the stand-alone ones and the sequential quadratic programming (SQP) with global search indicates a superior performance than other techniques. Finally, based on the present study, the adaptive and dynamic penalties need further investigation to become more consistent with the implemented optimization algorithms.

Reflexivity and its importance to the process of qualitative research is examined in this column. To that end, the definition of reflexivity is entertained followed by a discussion related to its inclusion in several versions of standards of qualitative research. Finally, a consideration of how reflexivity in articles should be written is undertaken.

A magic cube of order n is an n×n×n array containing each of the first n3 positive integers exactly once, such that the sum of entries in every row, every column, and every pillar are the same. We ...

An automated online column extraction coupled with high-performance liquid chromatography (HPLC) and equipped with a double-trap column system was developed to determine valproic acid in human plasma without derivatization for routine therapeutic drug monitoring (TDM). 300 μL of plasma sample pretreated by precipitating the protein was injected into a Diamonsil C18 extraction column in the first focusing step. After the elution of the pretreated sample, the targets were transferred from the extraction column to a strong cation exchange trap column through “central cutting” mode in the second focusing step. Finally, the targets were transferred from the strong cation exchange trap column to reverse-phase C18 analytical column and were detected under an UV wavelength of 215 nm. In this method, the extraction system performs the sample injection, extraction, and transfer of targets from the extraction column to one trap column. Meanwhile, the analytical system performs the transfer of targets from other trap column to the analytical column, separation, and detection of targets. This method showed good linearity of calibration curve (R = 0.9999), precision (relative standard deviation (RSD)

In highly congested crowd scenes, it is hard to generate high-quality density maps because the crowd and background are highly mixed such that it is difficult to distinguish them. To alleviate the issue, this paper presents a deeper multi-column dilated convolutional network (DMDCNet) method, which is capable of extracting sufficient semantic features for crowd understanding in highly congested crowd scenes. In DMDCNet, there are two modules: feature extractor and density map estimator. Feature extractor is a VGG-16-based convolutional neural network (CNN), which is able to extract low-level features contained in crowd images. Density map estimator is designed as a multi-column structure of dilated convolutional neural networks (DCNNs) to further extract the deeper information and capture multi-scale contextual information, which could generate high-quality density maps from the input images. Furthermore, multi-column DCNNs in DMDCNet can effectively alleviate the “gridding” problem caused by the dilated convolution framework. Extensive experiments on several commonly used benchmark datasets are conducted to demonstrate the proposed DMDCNet, which shows that DMDCNet is comparable with the recent state-of-the-art methods.

The study investigated awareness and use of cloud computing; its implications by libraries in selected academic libraries in Imo State, Nigeria. Four research questions were asked and answered. Also, three hypotheses were formulated and tested at 0.05 significance level. Survey research design was adopted. The total population of the study was 53 librarians, comprising professional staff of the library in Imo State University, Owerri, Federal Polytechnic, Nekede and Alvan Ikoku Federal College of Education, Owerri. The sample size was the entire population; hence the census enumeration sampling technique was employed. Rating scale was used for data collection. Data collected were presented in tables and column charts, and analyzed using mean, standard deviation. Testing of hypotheses was done using F-ratio (ANOVA) at the significance level of 0.05. Findings reveal that there is certain level of awareness on cloud computing technologies and models in the libraries studied. It was also discovered that cloud computing technology were used by libraries in the institutions studied, and economy of resource cost effectiveness and file sharing are some of the major positive implications of librarians adoption cloud computing technologies. However security and privacy, multiple taxation were also identified as major negative implications of cloud computing adoption by the librarians in discharging their functions in the libraries. Based on these findings, recommendations were made.

— The present paper is an extension of the previous paper of the author where the flotation column dynamics has been investigated. Here we consider the case when particle sedimentation rate and bubble lifting speed depend on time and position in the column. We use the methods for examining the transmission lines set out in the papers mentioned in the References. We formulate a mixed problem for the system describing the processes in the column and present it in a suitable operator form. Then we prove an existence - uniqueness of generalized solution by the fixed point method. We show an explicit approximated solution as a step in the sequence of successive approximations.

Swapping a row with a row, a column with a column or row with a column are usual operations carried out to scramble the given input plain image. To introduce more complications for the potential hackers, a novel grayscale image encryption scheme using the variable length row-column swapping based scrambling (VLRCSBS) has been proposed in this study. Security of the cipher would be improved in this way. Two chaotic maps, Henon map and piecewise linear chaotic map (PWLCM) have been used. These maps provide three streams of random numbers. Two more streams of random numbers have been created by manipulating the two streams of Henon map. After the grayscale image is input, arbitrary row and column are selected from this image to realize the scrambling effects. A randomly selected vector of pixels from these selected rows and columns is swapped with each other for a number of times. If selected vectors of pixels intersect each other, then to avoid the loss of pixels data, an intersection filter (IF) has been employed to forgo the intersecting vectors of selected pixels from the row and column for swapping. Resultantly, the given image is confused abundantly. An Exclusive-OR(XOR) operation is conducted between the scrambled image and the keystream given by PWLCM to get the final encrypted image. In the previous studies, whole rows and whole columns were swapped with each other. Our study swapped randomly selected portions of the rows and columns for scrambling, which spawned more security. In order to introduce the plaintext sensitivity in the proposed cipher, the hash codes given by the SHA-256 hash function for each input image have been used to update the system parameters and the initial values of the chaotic systems. The value of information entropy attained through the proposed algorithm is 7.9975 which is very competitive. Besides, the simulation and the performance analyses with varied validation metrics express the robustness, defiance to the multifarious threats and potential for some real world application of the cipher.

Concrete filled steel tube (CFST) column is an important type of structural member and its protective design is essential to enhance its structural performance under various dynamic loads. Previously carried out studies on CFST columns tried to determine how to improve their structural response under various loadings, such as axial compression, lateral impact, blast, seismic, etc. Apart from investigations on transverse impact loading, the majority of the other studies on CFST under various loads established solutions and protective measures. Therefore, this study aim is to improve the performance of CFST under transverse impact loads. The geometrical and mechanical properties, boundary conditions, impact loading and dynamic explicit analysis employed in that study. This paper proposes a novel design in terms of cross-sectional configuration and smart materials to be applied on the CFST in order to improve its performance under lateral impact loading. The proposed investigation is exclusively numerical and its results were verified with the experimental results from literature. The considered three main variables were including (1) concrete-filled double skin steel tubular – CFDST with both first sandwich layer and internal carbon steel tube filled with normal strength concrete – NSC, (2) CFDST with first sandwich layer filled with Ultra High-Performance Fiber-Reinforced Concrete – UHPFRC. a. The parameters including failure modes, maximum mid-span deflection, and residual displacements were presented.

In early project stages often no simulation results are available for dividing wall columns. Hence, shortcut methods are used to estimate suitable vapor and liquid splits. In a previous paper it was shown that Vmin diagrams are a suited tool to satisfy this need. However, it has turned out that it shows weaknesses for columns with finite or non-optimal stages. This contribution closes that gap and presents an extended approach to derive suited initial guesses. For this purpose, the original Vmin diagram is combined with a heuristic approach to calculate Pareto-optimal column designs resulting in a stage-adapted Vmin diagram. A comparative study shows that the new approach is a powerful tool to generate reliable guesses for multiple dividing wall column simulations with finite stage numbers.

Recent advances in computing are widely leveraged to design energy-efficient computing platforms for Internet of Things. Especially, scans is a crucial operation that consumes major energy in main-memory column-stores. Scanning a column involves returning a result bit vector to indicate whether each record satisfies a predicate (i.e., a filter condition) or not. ByteSlice, as an existing storage layout, chops the data into multiple bytes, thus possessing early-stop capability by comparing high-order bytes while scanning data. However, the width of columns is usually not multiples of byte, and in these cases, the last-byte of ByteSlice layout is padded with zeros, which wastes the computation energy and the memory bandwidth. To make the scan operation energy-efficient, a lightweight index is squeezed into the bits that originally padded with zeros. In this way, our proposed storage layout DIFusion integrates the data and the index in a unified structure. DIFusion enables an energy-efficient scan because it inherits the early-stopping capability from ByteSlice and possesses the data-skipping ability at the same time. The experimental evaluation on TPC-H, SSB and the real workload shows promising speedup for scans on DIFusion.

The hardware design of the rectification unit for the production of isopropylbenzene in the presence of the AlCl3 catalyst is considered, the use of which has a number of problems associated with its corrosiveness, rapid deactivation, the complexity of regeneration, etc. One of the possible solutions to the listed technological disadvantages is the use of heterogeneous zeolite-containing catalysts. In this case, during the reconstruction of the existing production of isopropylbenzene in the technological scheme of separation of alkylate, three rectification columns are released, which are expediently used to separate the alkylate of ethylbenzene production. To study the possibility of using the discharging distillation columns, a computational experiment was carried out using the Honeywell UniSim Design modeling system, in which a model of the alkylate separation unit for ethylbenzene production was formed. The NRTL method was used as a mathematical package for calculating the thermodynamic properties of the mixture components. As a result of modeling the operation of the alkylate separation unit for each distillation column, the optimal operating process parameters were obtained: pressure of the top and bottom of the column, reflux ratio, temperature profile along the height of the column. The calculated material balance of the technological scheme shows that in the first distillation column, complete separation of benzene from the alkylation reaction mass is achieved, the second column ensures the production of commercial ethylbenzene, and in the third column, a fairly clear separation of diethylbenzene from the remaining components of the mixture is obtained. The performed computational experiment showed that for the organization of the stable operation of the technological scheme for the separation of alkylate in the production of ethylbenzene, it is possible to use all the considered distillation columns without changing their design parameters at a load on the reaction mass of alkylation of about 60 t / h.

Recommendation systems, social network analysis, medical imaging, and data mining often involve processing sparse high-dimensional data. Such high-dimensional data are naturally represented as tensors, and they cannot be efficiently processed by conventional matrix or vector computations. Sparse Tucker decomposition is an important algorithm for compressing and analyzing these sparse high-dimensional data sets. When energy efficiency and data privacy are major concerns, hardware accelerators on resource-constraint platforms become crucial for the deployment of tensor algorithms. In this work, we propose a hybrid computing framework containing CPU and FPGA to accelerate sparse Tucker factorization. This algorithm has three main modules: tensor-times-matrix (TTM), Kronecker products, and QR decomposition with column pivoting (QRP). In addition, we accelerate the former two modules on a Xilinx FPGA and the latter one on a CPU. Our hybrid platform achieves $23.6 \times \sim 1091\times$ speedup and over $93.519\% \sim 99.514 \%$ energy savings compared with CPU on the synthetic and real-world datasets., Comment: 10 pages, 7 figures, IEEE Transactions on Computer-Aided Design of Integrated Circuits and Systems

IoT Standards Matters will look at different segments of the IoT market as it relates to implementation and use of standards. Each column will select a particular vertical, and lay out the relevant standards and technologies that affect the evolving IoT hyperspace. The pace of the columns will start broadly with the vision of narrowing the subject of subsequent articles toward more specific applications of standards, whether in the development, application, test, or commissioning of IoT technologies.

The General Purpose Heat Source (GPHS) is a radioactive heat source that consists of a stacked column of several individual modules. These modules contain and protect ceramic nuclear fuel pellets that give off heat for producing electricity. Each GPHS module contains passive safety provisions against fuel release that are the protective layers. High impact resistance was one of the dominant goals for the GPHS module designs. For increasing the ability of GPHS module to withstand the impact, a parametric FE-model is generated in the ANSYS Workbench environment. This model, consisting of a parametric geometry and its associated finite element entities, is used for geometric optimization. Several factors are considered in the design of the heat source module. Based on the analysis results, recommendations on optimization are provided.

Welcome to the fifth IT Professional issue of 2021, devoted to digital transformation (DT). It presents four peer-reviewed papers on this theme, four peer-reviewed feature papers on different topics, and column/department articles that align to probe deeper into DT.

In response to a question posed by a valued colleague, this column will discuss 4 fundamental pharmacokinetic concepts: (1) What does the term clearance encompass? (2) What do the terms first order and second order pharmacokinetics mean? (3) What does the term nonlinear pharmacokinetics mean and is it just a synonym for zero order pharmacokinetics? (4) What is the clinical relevance, if any, of these concepts and why? In addition, this column cites several earlier columns that are relevant to aspects of each of the answers. Thus, readers interested in more details can refer to these earlier publications that include case examples and figures that further illustrate various points. In considering the clinical relevance of these pharmacokinetic concepts, this column discusses relative binding affinity for targets and the concept of selective versus nonselective drugs, which are foundational cornerstones for understanding and optimally using currently available psychopharmaceutical agents.

In the past decade or so, vulnerability has become a fairly prominent concept in human rights law. It has evolved from being an underlying notion to an explicit concept. This column takes stock of vulnerability's relationship to, and possible influence on human rights law, assessing the concept's potential and pitfalls. It focuses on the not altogether unrelated issues of migrants’ social rights and on the role of human rights in environmental protection. The discussion commences with a reflection on the potential of vulnerability to re-interrogate those aspects of the human rights paradigm that relate to environmental protection. The next section focuses on the potential of vulnerability to enhance migrants’ social rights within human rights law. Subsequently, it focuses on the pitfalls and the difficulties of the vulnerability concept. It concludes by offering an outlook for the future of the concept.

Traditional metaphor researches consider metaphors as a rhetoric device for ornamental study. In 1980, Lakoff and Johnson put forward the Conceptual Metaphor Theory, which marks the shift of metaphor study from rhetoric view to cognitive view. Since then, numerous studies at home and abroad on conceptual metaphors have emerged. Economic news has also become a research interest. However, few research concerns about The Economist, let alone Finance & Economics Column inside. Therefore, this study explores the conceptual metaphors in the Finance & Economics Column of the Economist with Conceptual Metaphor Theory as a theoretical foundation. In order to address the above questions, the paper selects articles from October 2019 to December 2019 in The Economist and employs both qualitative and quantitative approaches to analyze conceptual metaphors in the self-constructed corpus. The results show that: firstly, altogether 443 conceptual metaphors are identified in the corpus, covering structural metaphor, ontological metaphor and orientational metaphor. Due to space limitation, only JOURNNEY metaphor, HUMAN BEING metaphor and UP/DOWN metaphor with high frequency is selected to be analyzed in detail. And their frequency varies from each other. Secondly, these three metaphors are identified in the corpus function by mapping from the source domain to the target domain. Finally, the frequency of these three metaphors is different lies in the systematicity, cultural coherence of metaphors and characteristics of economic news. This study enlarges the scope of conceptual metaphor and helps enhance their metaphorical awareness in economic discourses.

[EN] The networks of various problems have competing constituents, and there is a concern to compute the strength of competition among these entities. Competition hypergraphs capture all groups of predators that are competing in a community through their hyperedges. This paper reintroduces competition hypergraphs in the context of Pythagorean fuzzy set theory, thereby producing Pythagorean fuzzy competition hypergraphs. The data of real-world ecological systems posses uncertainty, and the proposed hypergraphs can efficiently deal with such information to model wide range of competing interactions. We suggest several extensions of Pythagorean fuzzy competition hypergraphs, including Pythagorean fuzzy economic competition hypergraphs, Pythagorean fuzzy row as well as column hypergraphs, Pythagorean fuzzy k-competition hypergraphs, m-step Pythagorean fuzzy competition hypergraphs and Pythagorean fuzzy neighborhood hypergraphs. The proposed graphical structures are good tools to measure the strength of direct and indirect competing and non-competing interactions. Their aptness is illustrated through examples, and results support their intrinsic interest. We propose algorithms that help to compose some of the presented graphical structures. We consider predator-prey interactions among organisms of the Bering Sea as an application: Pythagorean fuzzy competition hypergraphs encapsulate the competing relationships among its inhabitants. Specifically, the algorithm which constructs the Pythagorean fuzzy competition hypergraphs can also compute the strength of competing and non-competing relations of this scenario., Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature., Publicación en abierto financiada por el Consorcio de Bibliotecas Universitarias de Castilla y León (BUCLE), con cargo al Programa Operativo 2014ES16RFOP009 FEDER 2014-2020 DE CASTILLA Y LEÓN, Actuación:20007-CL - Apoyo Consorcio BUCLE

This paper deals with the free vibration and buckling of heavy column, considering its own self-weight. The column has a regular polygonal cross-section with a constant area. The column is applied to an external axial load as well as the self-weight. The five end conditions of the column are considered. Based on equilibrium equations of the column element, differential equations governing the vibrational and buckled mode shapes of column are derived. In solution methods, differential equations are numerically integrated by the direct integration method and eigenvalues of the natural frequency, buckling load and self-weight buckling length are calculated by the determinant search method. The numerical results of this study were in good agreement with those of the reference. Parametric study of the end condition, side number and self-weight on the natural frequency and buckling load was carried out.

We are approaching the 20‐month mark on the historic closure of school buildings and the move to remote instruction doe to the COVID‐19 pandemic. Public health directives currently allow options for remote, online, blended, and fully in‐person educational delivery in some parts of the world, but there is still a need for precautions and vigilance. Due to these circumstances, the need for policies that support online and digital learning has increased. This column argues for the need to consider digital literacies as part of comprehensive plans for online learning inside and outside of pandemics. The author provides background information on the various levels of preparation for pandemic learning in various US states, familiarizes readers with some current plans in state legislatures about online learning, and theorizes how digital literacies might be included in policies moving forward. [ABSTRACT FROM AUTHOR] Copyright of Journal of Adolescent & Adult Literacy is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The longest ozone column measurement series are based on the Dobson sun spectrophotometers developed in the 1920s by Prof. G. B. W. Dobson​​​​​​​. These ingenious and robustly designed instruments still constitute an important part of the global network presently. However, the Dobson sun spectrophotometer requires manual operation, which has led to the discontinuation of its use at many stations, thus disrupting long-term records of observation. To overcome this problem, MeteoSwiss developed a fully automated version of the Dobson spectrophotometer. The description of the data acquisition and automated control of the instrument is presented here with some technical details. The results of different tests performed regularly to assess the instrument's good working conditions are illustrated and discussed. Compared to manual operation, automation results in a higher number of daily measurements with lower random error and additional housekeeping information to characterize the measuring conditions. The automated Dobson instrument allows for continuous observation of the ozone column with a resolution of ∼ 1 DU under clear-sky conditions.

In this paper, a new form of structural design of the combination column—Cellular U-shaped steel combination column, as vertical force components applied to steel structure buildings. By changing the diameter size of honeycomb holes, the thickness of U-shaped steel and embellished plates, and the steel strength, the seismic properties of this new combination steel column are studied by using ABAQUS finite element software. Results the setting of honeycomb hole is reduced by part, the delay of the test piece and its energy consumption capacity are improved to varying degrees, the stiffness degradation rate is improved, and the setting of honeycomb steel plays a certain role in the seismic performance of the steel column. The experiment is used as a reference, and the destruction form and carrying capacity are compared, so that the numerical model has some credibility. Results the strength and stiffness of the cell U-shaped steel grid composition column are analyzed to meet the standards, the seismic performance is good, and can be applied to engineering practice.

In the building industry, ground improvement techniques based on stone column are widely employed. It is a very successful approach for enhancing the engineering characteristics of soil in all aspects, as well as reducing the settling issue in poor-grounded soils including silt, clay, silty sand, and organic soil. The performance of stone columns, is determined by the confining pressure provided by the surrounding soils. Engineering constructions built on thick layers of soft soil strata face issues such as limited bearing capacity, excessive total and differential settlement, lateral spreading, and so on. To address such issues, many ground improvement techniques are available. In exceptionally soft soils, the lateral confining pressure may be inadequate, resulting in column bulging failure. Individual stone column encasement improves lateral resistance to bulging by adding restricting pressure. This research focuses on the geotechnical aspects of building on closed landfill sites. A total of 33 models were tested in a geotechnical engineering laboratory on virgin former landfill soil and stone column with and without encasement in this current study. The increased diameter, length and L/D ratio of the column has demonstrated that the load capacity has increased and soil settling has decreased. When an unreinforced stone column has been installed, the ultimate bearing capacity of landfill soil is increased by 75-112.50 per cent and 87.50-176 per cent respectively, for 10mm and 20mm diameter stone column. Furthermore, when a fully reinforced stone column has been installed, it had increased by 156.25-212.50 per cent and 200-298 per cent for 10mm and 20mm diameters respectively. The stiffness of soil is increased by the stone column, which contributes to increase in the load capacity. The geogrid layer confines an aggregate, which contribute to enhance shear stiffness and bearing capacity.

This column examines the trends and changes that have been noted by this school librarian in the past 15 years of service.

The damage of reinforced concrete columns due to shear is often serious, so this type of failure should be avoided from the design. In this paper, a model derived based on the discrete computational method is proposed to calculate the shear strength of column carried by multi-spiral transverse reinforcement, accounting for the effect of compression depth. Furthermore, based on this model, a method is proposed to predict the failure mode of multi-spiral columns. The test database of multi-spiral columns from previous studies is used to validate both the shear strength and failure mode predictions. The proposed model with a crack angle of 40 degrees gives the best estimation of the shear strength of multi-spiral columns, and the proposed method predicts well the failure mode of these columns. To avoid shear failure, the ratio of the minimum shear strength calculated from the proposed model with a crack angle of 40 degrees to the shear force based on the moment-curvature analysis is suggested to be larger than 1.2.

PurposeIn this paper, a closed-form analytical solution for the prediction of moment-rotation and the rotational stiffness-rotation curves of I-shaped beam to cylindrical column connections, commonly used on offshore platforms, at room and elevated temperatures, are presented.Design/methodology/approachAn analytical solution for the prediction of moment-rotation and the rotational stiffness-rotation curves of I-shaped beam to cylindrical column connections is presented. The results of this model are compared with those of a non-linear coupled mechanical-thermal finite element model and small-scale experimental tests previously provided by the authors.FindingsIn this paper, a closed-form analytical solution for the prediction of moment-rotation and the rotational stiffness-rotation curves of I-shaped beam to cylindrical column connections, commonly used on offshore platforms, at room and elevated temperatures, is presented. The required yield and plastic moments in this model are provided as an extension to Roark's relationships. The results of this model are compared with those of a non-linear coupled mechanical-thermal finite element model and small-scale experimental tests previously provided by the authors. A reasonable agreement has been found between the analytical model results and the experimental/numerical modeling results.Originality/valueThis article is extracted from the author’s doctoral thesis, and all its achievements belong to the authors of the article.

Mexico highway network has more than 14,000 bridges. Most of them are reinforced concrete (RC) structures. The bridges design process incorporates the use of an overstrength factor that is not justified and has received little attention in published works. Mexican regulations allow using an overstrength factor for buildings in the range of 2?3, to reduce the design spectra as a function of the selected seismic behavior factor. However, for bridges, a single factor of 1.5 is proposed independent of any design parameter. The bridges in Mexico are mostly simply supported structures with maximum span lengths of 50 m. A relevant and distinctive aspect of the bridges designed in Mexico is the large load amplitudes of the trucks used to define the live load and the high seismic activity in the country. This study determines overstrength factors of a family of medium-length RC bridges composed of simply supported superstructures and substructure made up of single and multi-column RC piers. Non-linear dynamic analyzes using a set of 80 accelerograms were carried out. The results show that the height of the bridges and their seismic location are relevant parameters in the overstrength of the structures. Finally, analytical expressions are proposed to assess the overstrength factors of a very common bridge typology in Mexico and the world. 6612-034D-AE05 | PEDRO DA SILVA DELGADO N/A

The paper deals with the loading test results of an experimental reinforced concrete flat slab fragment, which was supported by an elongated rectangular column. The slab specimen was 200 mm thick and was without shear reinforcement. By experimentally obtained punching capacity, the accuracy of the standard design models for prediction punching resistance will be compared. The results of the experiment were also compared with the results of a numerical nonlinear analysis performed in the Atena program.

Although column flotation cells have been extensively studied in the literature, the hydrodynamic impact of orifice properties has not been adequately addressed yet. This paper initially investigat...

Due to the COVID-19 pandemic, many schools have been teaching music online. This is the second column of a two-part series exploring this topic. In this column, I discuss how general music teachers can share prerecorded lessons that contain interactive questions using Microsoft Stream and Forms.

In this study, a tracer field experiment was conducted to study the temporal dynamics of bromide movement in a loamy tile-drained agricultural landscape. Moreover, tritium leaching experiments were performed on undisturbed soil columns from the same field. The HYDRUS-2D software package was used to model water and solute transport. Three water flow models developed in Part 1-a single-porosity approach with modified soil hydraulic functions (SP), a dual-porosity approach (DP), and a dual-permeability approach (DUP)-were used as a foundation for building solute transport models, of which the initial parameterization was based on a suggested hydrogeological tool from previous studies. The selected solute transport models were an SP, an SP with immobile water, a DP, a DUP, and a DUP with immobile water. The model predictions were compared against measurements of bromide concentrations in soil-water. The DP captured the degree of the initial peaks and predicted well the shape of the observed concentrations. However, DP presented low capability to match the timing of bromide concentration peaks. In contrast, the DUP with immobile water illustrated better predictive ability by introducing an additional pore region into the matrix domain. Validation of field-scale solute transport models was implemented using the data from the following leaching experiments. The already suggested parameterization concept was further evaluated for its capability to provide a sufficient initial representation of the internal pathways. The output from such hydrogeological studies shows that macropores and their interconnection with tile drains are key to understanding the water flow and solute transport processes in loamy structured soils.