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Over the past decade, low graduation and retention rates have plagued higher education institutions. To help students graduate on time and achieve optimal learning outcomes, many institutions provide advising services supported by educational technologies. Accurate grade prediction is an integral part of these services such as degree planning software, personalized advising systems and early warning systems that can identify students at-risk of dropping from their field of study. In this work, we present next-term grade prediction models based on students' cumulative knowledge and co-taken courses. The proposed models are based on a matrix factorization framework and incorporate a co-taken course interaction function to learn the influence from the co-taken courses on the target course. The co-taken course interaction function is formed by a neural network, which takes the knowledge difference between the co-taken courses and the target course as input, and outputs an influence value that will be used to predict students' grades on the target course. The experimental results on various datasets from a U.S. University demonstrate that the proposed models significantly outperform competitive baselines across different test sets. Furthermore, we analyze the proposed models' performance with different numbers of co-taken courses as well as different numbers of co-taken course subjects, and highlight with an application case study how a student might make decisions related to selection of courses. The codes are available at https://github.com/Zhiyun0411/EDM. [For the full proceedings, see ED599096.]

There is a critical need to develop new educational technology applications that analyze the data collected by universities to ensure that students graduate in a timely fashion (4 to 6 years); and they are well prepared for jobs in their respective fields of study. In this paper, we present a novel approach for analyzing historical educational records from a large, public university to perform next-term grade prediction; i.e., to estimate the grades that a student will get in a course that he/she will enroll in the next term. Accurate next-term grade prediction holds the promise for better student degree planning, personalized advising and automated interventions to ensure that students stay on track in their chosen degree program and graduate on time. We present a factorization-based approach called Matrix Factorization with Temporal Course-wise Influence that incorporates course-wise influence effects and temporal effects for grade prediction. In this model, students and courses are represented in a latent "knowledge" space. The grade of a student on a course is modeled as the similarity of their latent representation in the "knowledge" space. Course-wise influence is considered as an additional factor in the grade prediction. Our experimental results show that the proposed method outperforms several baseline approaches and infer meaningful patterns between pairs of courses within academic programs. [For the full proceedings, see ED596512.]

The past few years has seen the rapid growth of data mining approaches for the analysis of data obtained from Massive Open Online Courses (MOOCs). The objectives of this study are to develop approaches to predict the scores a student may achieve on a given grade-related assessment based on information, considered as prior performance or prior activity in the course. We develop a personalized linear multiple regression (PLMR) model to predict the grade for a student, prior to attempting the assessment activity. The developed model is real-time and tracks the participation of a student within a MOOC (via click-stream server logs) and predicts the performance of a student on the next assessment within the course offering. We perform a comprehensive set of experiments on data obtained from two openEdX MOOCs via a Stanford University initiative. Our experimental results show the promise of the proposed approach in comparison to baseline approaches and also helps in identification of key features that are associated with the study habits and learning behaviors of students.

This study used eye-tracking technology to track students' eye movements while searching information on the web. The research question guiding this study was "Do students with different search performance levels have different visual attention distributions while searching information online? If yes, what are the patterns for high and low performing searchers?" 14 university students in Macau were invited to search an answer online for the question: "After you clean a glass with tap water, why are there always some water drops remaining in the glass surface?" A Tobii Pro X2-30 remote eye tracker was used for data collection. Two students with the highest and lowest search task scores were selected for comparisons in their online search behavior and eye-movement patterns. The high-performing student worked more in revising search queries, and reading and assessing the information in the selected webpages for its relevance. Search patterns showed that the high-performing student tended to switch more frequently between search query box and search result page whereas the low-performing student tended to switch between the search result and selected web page. This implied that the high-performing student was more metacognitively engaged by revisiting and revising search queries to improve the quality of search results. [For full proceedings, see ED571459.]

Studies indicated Web 2.0 technologies can support learning. Then, integration of innovation may create concerns among teachers because of the innovative features. In this study, the innovation refers to Web 2.0 technology integration into instruction. To help pre-service teachers make the best use of the innovation in their future instruction, it is essential to examine the patterns of their concerns about integrating Web 2.0 technologies into their practice. About 350 future teachers participated in the study during the spring semester of 2012 in a northern university of Taiwan. The Stages of Concerns (SOC) Questionnaire was adopted to assess seven stages of concern: awareness, informational, personal, management, consequence, collaboration and refocusing. The findings of this study indicated the pre-service teachers' concerns as a whole were most intense respectively in the stages of informational, personal, and collaboration. A few implications were indicated for teacher education programs to alleviate the concerns. [For the full proceedings, see ED562107.]

This study examined the time different ability level examinees spend taking a CAT on demanding items to these examinees. It was also found that high able examinees spend more time on the pretest items, which are not tailored to the examinees' ability level, than do lower ability examinees. Higher able examinees showed persistence with test questions, regardless of the item's difficulty level on operational and pretest questions they answer correctly or incorrectly. Results showed that more able students spend more time on all items, regardless of whether the items are answered correctly or incorrectly. These results were consistent for male and female examinees and for US and non-US administration sites.

This study investigates and compares American and Chinese secondary students' science achievement, their attitudes toward science, and other factors influencing science learning. The subjects, in Grades 7-12, include Chinese students (N=495) and American students (N=469). A survey of attitudes towards science developed by the authors was employed and the data used to analyze student achievement and attitudes toward science. The discussion of results centers on comparison of student attitudes toward science by country, grade level, and gender. Findings suggest that a student's nationality has a much greater effect on science attitudes than gender or grade level. (DDR)

An experiment with reflective teaching methods was conducted with six undergraduate and seven graduate student teachers majoring in applied linguistics and English-as-a-Second-Language (ESL) teaching and minoring in education. The student teachers were placed in urban elementary, middle, and high schools in a variety of ESL program types and with a variety of student proficiency levels. Each wrote in a journal and compiled a teaching portfolio during the 15-week student teaching experience, both to promote reflection on teaching practice and to allow assessment of their progress. The portfolio was to include reflections on both successful and unsuccessful teaching, to be complemented by seminar discussions and readings encouraging reflection. Journal entries (free-written and on assigned topics), students' reading discussions and questions, notes from observations and student teacher conferences, portfolios, and final portfolio reflections were analyzed for emerging themes and connections among them. Salient themes included: encountering a wide range of differences among students; teaching the lesson vs. teaching the students; gaining insights into students' learning; and reconstructing teaching knowledge. Results are discussed, using excerpts from student writings, and recommendations are made for teacher education. Contains 10 references. (MSE)

A study at Queens College (City University of New York, New York) investigated the literacy backgrounds of nine non-native-English-speaking students of varied ages and language groups who failed the freshman composition test. Data were gathered in focused interviews (questions appended), which asked for the student's recollections of the experiences of learning to write in the native language, of learning to write in English, and difficulties in dealing with the composition test. Results indicated the students had had extensive writing instruction before coming to the United States, and came from home backgrounds having similarities in writing experience. However, their educational backgrounds varied in emphasis on the function and genre of writing. Formal writing was often connected with study of literature. Students had varied cultural educational and cultural constructions of the writing experience in three areas: interpreting a writing task; anticipating the reader's needs; and developing and organizing ideas. The interviews confirmed some findings of contrastive rhetoric research on organizational patterns, but also suggest that cross-cultural differences are not limited to the organization of writing, but are also shown in how the writer approaches and interprets a writing task and goes about orienting the reader. Contains 19 references. (MSE)

A study investigated the effects on student teachers of peer responses offered through dialogue journals on English-as-a-Second-Language (ESL) teacher education. Subjects were nine students in a student teaching seminar, all involved in practicums in public high schools. Over 15 weeks, students wrote journal entries both on selected topics from common readings and discussions and on concerns and reflections arising from practical experience. Students read and responded to each others' journals once a week. The 79 journal entries and 332 peer responses were analyzed for themes and patterns. Results indicate the peer responses: (1) enhance open dialogue and class community building, (2) lead to problem solving, (3) foster collective reflection, and (4) help with the socialization process. It is concluded that peer responses in such a course have rich instructional potential. Teacher trainers are encouraged to create opportunities and model responses for peer feedback, provide focal points for teacher reflection, and adjust instruction based on students' needs and issues as reflected in the journals. Journal excerpts and peer responses are included. (MSE)

A study examined the supervisory relationship between a non-native English-speaking doctoral student and a native English-speaking advisor, particularly in science, focusing on factors leading to effective or ineffective supervision, advisee response to advisor guidance and assistance, and the roles played by the two participants. Subjects were three Chinese students, one female and two male, in different fields (biochemistry, genetics, ecology) and three male doctoral advisors. Data collection spanned a 6-month period, with data gathered from dissertation drafts and advisors' written comments on them, observations and field notes of writing conferences and research group lab meetings, a variety of student and institutional documents, and students' English and Chinese literacy histories. The three case studies are presented in narrative form. It is concluded that the advisor's cross-cultural awareness and the style taken in relation to the student's preference do affect dissertation supervision. Implications for further research and practice are discussed briefly. Contains 31 references. (MSE)

The paper explores the significance of a contrast between generalized phrase structure grammar (GPSG), a context-free grammar with a well structured theory of features, and head-driven phrase structure grammar (HPSG), a mechanism for increasing the power of GPSG by introducing head-wrapping and lexical rules, using examples from Mandarin Chinese. A study focusing on the discontinuous idiom chunks of possessive object (POBJ) construction produced the unexpected result that even though head-wrapping is a syntactic operation introduced to account for discontinuous constituencies, POBJ data cannot be accounted for with the Head-wrap mechanisms. The adoption of Head-wrap operations as the only explanation of discontinuous constituencies predicts that one of the disjoint sub-strings must have the head of the entire constituent on its edge. The validity of Head-wrap as the mechanism for accounting for the discontinuity of syntax is challenged by the fact that the frequency/duration adverbial splits the POBJ predicate non-adjacent to the head. The failure of grammars with head-wrapping to produce a straightforward syntactic solution to the POBJ data calls for a closer examination of non-syntactic approaches. (MSE)

The persistent black-white homeownership disparity in the U.S. has triggered tremendous research and policy interests to explain and address the issue. However, previous efforts disproportionately focused on the mortgage market rather than the home-owning family. This imbalance leads to an under-exploration of how African-American families' socioeconomic challenges that are external to mortgage-market evaluations, undermine their ability to sustain homeownership status. This study proposes a new framework for understanding black-white inequality in homeownership sustainability, which centers on the mediating role of liquid assets. Based on the Panel Study of Income Dynamics (PSID), the framework is put to an empirical test on the differential exit rates between black and white homeowners during the Great Recession. The findings indicate that (1) the racial gap becomes statistically non-significant after liquid wealth is controlled in the model alongside other covariates, and (2) the inclusion of liquid wealth renders mortgage-oriented variables non-significant, with regard to either homeownership sustainability in general or the black-white disparity in particular. Moreover, the subsample analysis by race reveals different coping mechanisms of the two groups during the housing crisis, as liquid assets played a significant role in white families' chances of homeownership retention while black homeowners depended more on non-liquid assets. [ABSTRACT FROM AUTHOR]

The article discusses research which developed a two-way coupled moving solid model algorithm for rock-slide generated tsunamis. Topics discussed include the implicit velocity correction method (IVCM), the numerical model based on the finite volume method (FVM) to solve the large-eddy simulation (LES) model and free surface by the volume of fluid (VOF) method.

The East Asian buprestid Agrilus smaragdifrons Ganglbauer is reported for the first time in the Western Hemisphere. Specimens of this species taken from emerald ash borer ( A. planipennis Fairmaire) monitoring traps in New Jersey in 2015-2016 suggest establishment of this metallic wood-boring beetle in the northeastern United States. The earliest known record of A. smaragdifrons in the U.S. is based on a verifiable image found on BugGuide, from a specimen collected in Hudson County, New Jersey in June 2011. Diagnostic information and high-resolution images of the adult male, female, and the male aedeagus are provided to help facilitate the recognition of this adventive buprestid from other North American Agrilus. A summary of information about the host plant ( Ailanthus altissima), native distribution, and biology are given, and all known North American records are listed and mapped. [ABSTRACT FROM AUTHOR]

Particulate matter pollution causes a serious health risk to individuals. Nanofibrous air filters have gained attention recently due to their high surface-to-volume ratio, which could increase the contact area between the fine particles and the nanofibers, and hence improve the filtration efficiency. However, their application is constrained by the limited air permeability because of the dense nanofibrous filter construction. This problem could be resolved by creating nanofibrous filters with extended fibrous architecture and surface functional alternatives. In this presentation, we will give three examples of electrospun, fiber-based air filters with a variety of fiber morphologies and diameters, pore sizes and porosities, surface charge densities, and anti-wetting properties. By constructing composite filters with a delicately sequenced pattern of fiber layers and carefully selected polymeric materials, the fabricated air filters performed with excellent filtration performance, delightful long-term service life, and durable cleanability and reusability. In brief, the electrospun TPU/PS/PA-6 filter with submicron, nano, and beaded fibers displayed remarkable filtration efficiency (>99.99%) and low filtration pressure (54 Pa); the composite electret media performed with a satisfied holding capacity of 14.1 g/m2, which was 5-10 times higher than existing commercial air filters; and the window-based fluorinated PVDF-HFP/SiO2 filters with amphiphobicity demonstrated robust cleanability and reusability after 10 times spray cleaning cycles. These highperformance, electrospun air filters would have the potential for usage in air cleaners or ventilation systems, facial masks or protective suits, window-based filters, etc. [ABSTRACT FROM AUTHOR]

The paper proposes a numerical method for analyzing nonlinear wave loads using a hydroelastic model. The numerical analysis method utilizes a 3-D Green function method and a 2-D momentum model, which are coupled in the time domain. The computational results were compared with those of a model test of a 10000-TEU containership. The different components (low frequency wave component, high frequency whipping component and combined total component) of experimentally and numerically determined sectional vertical bending moment (V.B.M) to regular waves were compared. Furthermore, discussions are made on how much the whipping component contributes to the total V.B.M, which are observed and calculated in regular waves, and how to choose the design wave loads and combine different components of vertical bending moment. [ABSTRACT FROM AUTHOR]

The development of oil and gas fields in the arctic brings to the table several challenges in the use of structural steels, particularly concerning their low-temperature properties. Among others, also fatigue behavior needs to be accounted for when using structural steels for arctic applications. As for static fracture, ferritic steels experience a fatigue ductile to brittle transition (FDBT) when temperature is decreased below a certain temperature. This may result in higher crack growth rate and, consequently, unpredicted fatigue-related failure. In order to shed some more light on this phenomenon, fatigue crack growth tests have been performed on a 420 MPa structural steel weld simulated coarse grained heat affected zone (CGHAZ) at different temperatures: room temperature, -30, -60. -90 and -120 °C, with -60 °C considered as a possible design temperature relevant for the most extreme arctic areas. Post-mortem fracture surface investigations have been also conducted in order to confirm the expected switch in fatigue crack growth mechanisms as temperature is lowered below the FDBT temperature. Finally, two analytical equations, valid for temperature ranges above the FDBT. were established based on the experimental results to relate yield strength and temperature variation of the Paris law constants . These are used to quantify the temperature impact on the designed fatigue life, and the results are compared to the actual design rules (BS 9710). [ABSTRACT FROM AUTHOR]

For steel structures to be installed in the Arctic region, the risk of brittle fracture represents a primary concern due to the ductile to brittle usually transition taking place at sub-zero temperatures. Therefore, the present investigation addressed the heat affected zone and weld metal toughness of two extra low carbon steels of 420 MPa yield strength grade, supplied in 20 and 50 mm thickness. The testing included tensile, Charpy V and CTOD. The results obtained showed that the Charpy V toughness was relatively high at -60°C, but that some low values may occur for the fusion line position. The fracture toughness at -60°C, based on SENB05 (a/t=0.5) geometry, appeared to be low for both weld metal and fusion line positions. More specific measures may be taken into account in welding procedure qualification of the current steels, such as using lower crack length (e.g., a/t=0.2), tension instead of bending (SENT testing) or a full engineering critical assessment. [ABSTRACT FROM AUTHOR]

This state-of-the-art paper is devoted to testing and evaluation of microstructural crack arrest. Testing and analysis of crack arrest have developed in the last decades, enhancing our understanding of the mechanisms behind crack arrest in a continuum mechanics perspective. Understanding crack arrest is important when operations are moving towards Arctic regions as low temperatures are detrimental to most steel's fracture toughness. Large-scale testing is expensive and unpractical, and current methods fail to reflect the microstructural and micromechanical features of the fracture process. In order to increase the effectiveness of characterizing crack arrest properties, small-scale tests, as well as numerical methods, have been developed. The mechanical basis and mechanisms behind crack arrest are presented. Global and micro-arrest is considered. Key methods for understanding, evaluating and obtaining arrest parameters are presented: (i) statistical treatment of experimental results, (ii) barrier models for separating fracture and arrest sequences, and (iii) numerical tools for determining arrest behaviour. Brief presentations of the main mechanisms of crack arrest are presented with focus on the micromechanisms of arrest. The effect of grain boundaries, lattice orientation and second-phase particles upon propagation controlled cleavage are discussed, as well as their role in the arrest mechanism. Developments in arrest testing and evaluation are presented. Experimentally and numerically obtained results are linked to relevant mechanisms and theory, exhibiting the predictability and importance of crack arrest properties, and the understanding of the governing mechanisms behind crack arrest. The potential for increased understanding of the brittle fracture arrest phenomenon associated with new methods for nanomechanical testing of the material properties inside individual grains, and over grain boundaries, as well as the rapidly improving capabilities of atomistic modelling of deformation and fracture, is presented to pave the way for the future research within this field. Areas where further research could enhance our knowledge of crack arrest are listed. [ABSTRACT FROM AUTHOR]

In this paper, the transverse vibration equation of a deep-water drilling riser-conductor system is established by exploiting the I Iamiltonian principle. While calculating the system kinetic energy, all these factors such as fluid flow velocity, the tube and the auxiliary water quality of the tube are taken into account. Additionally, we consider the inside and outside fictitious pull of the tube wall respectively. Moreover, the additional pull of the system bending elongation and the settlement acceleration of the drilling platform are considered. Through ABAQUS software, the inherent frequency is obtained, and then we analyze the impact on the inherent frequency in different condition. In the end, dynamic mechanical properties of the system are analyzed within the time domain by considering many different factors. [ABSTRACT FROM AUTHOR]

The perforated caissons are widely used to decrease wave force and reflection effectively in costal engineering. The nonlinear interactions between waves and partially perforated caissons are investigated using the weakly compressible Smoothed Particle IIydrodynamic (WCSPII) method. An improved algorithm based on the dynamic boundary particles (DBPs) is proposed to treat the solid boundary. The performance of the model is validated by the analytical solution of the surface elevations and wave pressures in front of the vertical wall. The SPII results of the reflection coefficients of the perforated caissons are compared with the available experiment data and good agreements are obtained. The wave pressures on the perforated front wall and the rear wall are analyzed. The effects of the relative wave chamber width B/Lc and the porosity of the perforated wall on the wave energy dissipation of the perforated caissons are discussed. [ABSTRACT FROM AUTHOR]

Ship accidents occur most often to aged ships, and the main reasons obviously include corrosion and fatigue. Due to the special structural characteristics, the problem is more critical to catamarans' corner spots. Based on Paik corrosion model and the spectrum analysis method for fatigue strength, this paper studies the influence of randomly distributed corrosion on the fatigue strength of a catamaran's corner spots. According to the computation results, a prediction model for accumulated fatigue damage is proposed to guide ship construction. [ABSTRACT FROM AUTHOR]

The structural safety monitoring system for marine structure is based on the strain data which is measured by fiber optic sensors on some critical structure to detect early damage in structures. The system is designed to filter and process the data in real time to get parameters of the Rayleigh distribution on structural stress for the evaluation of yield strength using reliability method. The fatigue damage rates are also calculated using the rain-flow counting method and the Pahngren-Miner damage summation rule. These assessment results guide the staff to take measures for improving the life of marine structures in complex sea conditions. In addition, the experiment of a large scale ship model was carried out in coastal areas of China to demonstrate system effectiveness. [ABSTRACT FROM AUTHOR]

This paper introduces the design method of an expansive stressed grouted clamp on a joint of a jacket platform. The general design requirements are summarized initially. Then the four design principles are put forward. The principles including the verifications of slip capacity, bolt prying force and crushing loads help to determine the basic dimensions of clamp structure. The structural strength is checked by finite element method referring to the principle of structural strength. A design example that the clamp is used for repairing a K-joint of an offshore jacket platform located in the Bohai Sea is introduced to make a clear description of the design process. [ABSTRACT FROM AUTHOR]

An alternative methodology to laboratory tank measurement for ship hydrodynamic tests is introduced in this paper. The hydrodynamic testing approach proposed in this paper is to perform large-scale models1 tests in actual sea conditions. The waves model encountered at sea are wind-generated short-crested waves, which are closer to the realistic condition compared with the waves generated in the in-house tanks. Moreover, the models are self-propelled and are equipped with their superstructures and appendages, by which the wind and current effects are taken into account during the measurements. To conduct the tests, a large-scale segmented free running model and the testing system are designed. The overall arrangement of the model and the testing system are presented in detail. The experimental campaign of the large-scale model carried at Huludao Harbour of China is described and typical testing results obtained are presented. [ABSTRACT FROM AUTHOR]

In order to investigate wave load behavior of a large ship in different sailing states, segmented model tests and numerical calculation are conducted in this paper. Design of the segmented self-propelled model is introduced in detail. Combined tubular steel backbones are used to measure the vertical bending moment and torsional moment. A propulsion system is installed on the model to achieve the testing speed. Tests under different wave states were conducted in a tank. Numerical approach based on three-dimensional nonlinear time-domain theory is also used to calculate wave load response of the ship. The results obtained by tests and numerical simulation are analyzed and compared. [ABSTRACT FROM AUTHOR]

This paper covers the numerical investigation of slamming problem with 2-D wedge and ship section. Both of them are assumed as a rigid body and dropped into calm water with free falling. Because of the nonlinear behavior of water-entry wedge associated with violent freesurface motion including jet-like splash and water fragment, there are some difficulties in prediction numerically with conventional gridbased approach. In this study, a modified MPS (Moving Particle Semi-Implicit) method which is a particle-based approach and solves the continuity and Navier-Stokes equations for incompressible and viscous fluid has been used for representing time-varying entry velocity of rigid body, local pressure and vertical force on the body and the pressure distribution on the wet surface. The validation of the present simulation results are performed through the comparison with the experiments conducted in KRISO, Korea. [ABSTRACT FROM AUTHOR]

This paper presents a numerical study of flow over a circular cylinder al high Reynolds number using detached-eddy simulation (DES). The k-ω Shear Stress Transport (SST) based DES model is selected for handling massively separated flow. The computations arc performed with an O-type grid and the instantaneous and statistical characteristics of the turbulent wake flow behind the cylinder is extensively studied. The results are compared with the available experimental data, as well as the previously published numerical data obtained from Reynolds-averaged Navier-Stokes (RANS) and large-cddy simulation (LES). The incompressible flow assumption and finite volume discretization is adopted. All the works are carried out with the use of OpcnFOAM toolbox. [ABSTRACT FROM AUTHOR]

Based on the linearized equation of ship manoeuvring motion in 4 degrees of freedom, the coupled response models for ship manoeuvring and roll motions are derived, where the manoeuvrability indexes are expressed as a combination of the hydrodynamic derivatives. Taking the model of a container ship as study object, 5°/5°, 10710°, 15715° and 20720° zigzag tests are predicted by using the coupled response models with the manoeuvrability indexes determined by the hydrodynamic derivatives from RPMM tests. The predicted results are compared with the simulation results using the whole-ship mathematical model. Good agreement is achieved between the predicted and simulated results for 575° zigzag test, which shows the validity of the coupled response models in the prediction of ship manoeuvring and roll motions under small rudder angle. [ABSTRACT FROM AUTHOR]

China and India have become the epicenter of world urbanization since the last quarter of the 20th century. The large-scale and break-neck urbanization has posed severe governance challenges. Despite this unprecedented scale of urbanization, how Chinese and Indian cities are governed is not well understood and theorized. The existing theoretical work on urban governance rests heavily on the deindustrialization and economic restructuring in North America and West Europe in the second half of the 20th century. But Chinese and Indian cities do not fit neatly in the narrative of post-Fordism, late capitalism, and neoliberalization. Drawing upon fieldwork on land acquisition in Guangzhou and Kolkata metro regions, this talk discusses how the inherited forms of urban governance collide with neoliberal reforms, and how they shape citizens' struggle over housing, land, and environmental rights. I argue the urban processes in China and India have to be theorized in their own terms, instead of being interpreted as "variations of neoliberalism". [ABSTRACT FROM AUTHOR]

As a nation we have seen an increase in the number of singles over the past 4 decades. Researchers have linked these demographic changes to improvements to women's social and economic status. One thing we observe is that single women have become the second largest home buyer in the American housing market. In other words, more and more women are living the so-called Barbie life style: single, financially independent, and paying for a mortgage. Such extraordinary phenomenon calls for an in-depth study of this specific group's experience within the housing market. In this paper, we explore how the interaction of gender, marital dissolution, and children could affect single women's odds of owning a house. By analyzing AHS 2011 data, we find that race is a salient factor that diversifies homeownership across groups. Gender difference in homeownership is observed. Having a child or not has a significant impact on single women's access to housing wealth. Previous marriage experience demonstrates mixed impacts on homeownership. The interaction between the three variables exerts totally opposite impact on men and women. Ability to invest in other assets, high education and income, and non-central city residence all greatly increase single women's chance of owning a house. [ABSTRACT FROM AUTHOR]

The article discusses research which explored the methane hydrate (MH) dissociation in homogeneous porous media by mesoscale modeling. Topics discussed include the development of a finite volume method with unstructured mesh, Navier-Stoke's equations for the incompressible flow around MH's surface and types of cells in the unstructured grid system.

The article discusses research which examined the tensile properties of 420 MPa steel exposed at low temperature. Topics discussed include the dependency of yield stress, tensile strength and strain hardening on temperature, proposed correction of yield stress and Lüders band development at low temperature and effect of temperature dependent material properties on brittle fracture.

The article discusses research which investigated the change of biogenic barium (Ba) content in Pacific ferromanganese crusts and their relationships with paleoproductivity fluctuations. Topics discussed include the variations related to biogeochemicals processes and age models, calculations of biogenic Ba and mass accumulation rates.

The article discusses research which examined the properties in submerged arc welding of X80 plate in Arctic areas. Topics discussed include the increase in ultimate strength of the base metal and weld metal yield with falling temperature, weld thermal simulation, testing and characterization for welds, weld macros and hardness and fracture toughness.

The article discusses research which investigated a data management system for material assessment at low temperature. Topics discussed include the proposed generic database platform for efficient access to material data, analysis of various materials including steels/weldments and aluminium alloys and improved design guideline for materials requirements in Arctic conditions.

The article discusses research which examined the fatigue crack growth rate tests performed on a structural steel at low temperature. Topics discussed include the effect of low temperature on fatigue crack growth, chemical composition and mechanical properties of steel and improvement of all the stages of the fatigue crack growth as the testing temperature is lowered from room temperature.

The article discusses research which examined the tsunami risk map for Gongliao District in Taiwan. Topics discussed include the scenarios conducted by Cornell Multi-grid Coupled Tsunami model (COMCOT) developed by Professor Philip L.-F. Liu, some factors affecting the hazard, calculation of the water speed of the grid in the village and rising rate of water surface level.