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Joon Y. Park is one of the pioneers in developing nonlinear cointegrating regression. Since his initial work with Phillips (Park & Phillips, 2001) in the area, the past two decades have witnessed a surge of interest in modeling nonlinear nonstationarity in macroeconomic and financial time series, including parametric, nonparametric and semiparametric specifications of such models. These developments have provided a framework of econometric estimation and inference for a wide class of nonlinear, nonstationary relationships. In honor of Joon Y. Park, this chapter contributes to this area by exploring nonparametric estimation of functional-coefficient cointegrating regression models where the structural equation errors are serially dependent and the regressor is endogenous. The self-normalized local kernel and local linear estimators are shown to be asymptotic normal and to be pivotal upon an estimation of co-variances. Our new results improve those of Cai et al. (2009) and open up inference by conventional nonparametric method to a wide class of potentially nonlinear cointegrated relations.

This chapter provides a synthesis of the research project which investigated whether or not the most recent mathematics curriculum reform has reached the classroom and influenced classroom practice and student learning in the mainland China. Three types of evidence for change as a result of the curriculum reform were examined. These included the beliefs and perceptions of teachers about learning and teaching mathematics, the cognitive features of learning tasks and of classroom interaction that were implemented in classroom, and student learning outcomes. Two groups of elementary math teachers and their students participated in the study. One group had participated in the reform implementation in classroom for several years, and the other group had used the conventional curriculum when the project was conducted in 2005. About 150 videotaped class sessions were analyzed from 58 classrooms of the two groups. Survey methods were used to probe the changes in the beliefs and perceptions of teachers about teaching and learning mathematics. The student learning outcomes were assessed for three times with multiple measures of mathematics achievement. Findings of the project provide the converging evidence that the curriculum reform has resulted in some of the expected changes. Reform teachers were more likely to hold a dynamic view of mathematics and to indicate the importance to provide students the learning opportunity to hypothesize, to proof, and to communicate in learning mathematics. The reform classrooms used more learning tasks with higher cognitive demands. The teachers in the reform classrooms asked more questions that required students to describe procedures leading to their answers and the students in the reform classrooms raised more questions in learning mathematics. Students of the reform classrooms showed to have achieved a relatively more balanced development in different cognitive areas of mathematics achievement.

Insufficient intra-organizational diffusion of prefabricated construction (PC) technology hinders its implementation benefits. More research on intra-organizational diffusion of PC technology is required to improve organizational performance in PC implementation. This study aims to explore the antecedents and consequence of intra-organizational diffusion of PC technology.

This study established an antecedent and consequence model of intra-organizational diffusion of PC technology from the perspective of contingency theory. The model was empirically tested by 91 valid questionnaires using partial least squares-structural equation modeling (PLS-SEM).

The results indicate that organizational support (OSU), organizational climate (OC) and mechanistic organizational structure (OST) positively influence intra-organizational diffusion of PC technology, which further positively influences organizational performance. The relationship between OC and intra-organizational diffusion of PC technology is mediated by OSU. Technological turbulence negatively moderates the relationship between OSU and intra-organizational diffusion.

This is the first paper to study the antecedents and consequence of intra-organizational diffusion of PC technology and an expansion of contingency theory in the research field of PC technology. This study helps to theoretically stimulate future research on intra-organizational diffusion and practically promote intra-organizational diffusion of PC technology along with improving organizational performance in its implementation.

The aim of this study is to numerically simulate the density-driven convection in heterogeneous porous media associated with anisotropic permeability field, which is important to the safe and stable long term CO₂ storage in laminar saline aquifers.

The study uses compact finite difference and the pseudospectral method to solve Darcy’s law.

The presence of heterogeneous anisotropy may result in non-monotonic trend of the breakthrough time and quantity of CO₂ dissolved in the porous medium, which are important to the CO₂ underground storage.

The manuscript numerically study the convective phenomena of mixture contained CO₂ and brine. The phenomena are important to the process of CO₂ enhanced oil recovery. Interesting qualitative patterns and quantitative trends are revealed in the manuscript.

This paper considers the problem of estimating a partially linear varying coefficient fixed effects panel data model. Using the series method, we establish the root N normality for the estimator of the parametric component; and we show that the unknown function can be consistently estimated at the standard nonparametric rate. Furthermore, we extend the model to allow endogeneity in the parametric component and establish the asymptotic properties of the semiparametric instrumental variable estimators.

In this chapter, we consider the nonparametric estimation of the average treatment effect (ATE) based on direct estimation of the conditional treatment effect. We establish the asymptotic distribution of the proposed ATE estimator. We also consider consistent testing for a parametric functional form for the conditional treatment effect function. A small-scale Monte Carlo simulation study is reported to examine the finite sample performance of the proposed estimator.

The purpose of this paper is to study the seismic performance of the energy-saving block and invisible multi-ribbed frame composite walls (EBIMFCW), changing the shear-span ratio as the test parameter, the low-cycle reciprocating loading tests of six 1/2 scale wall models were carried out.

The test design method and analysis are used for the seismic performance of the EBIMFCW.

With the increase of shear-span ratio: the walls tend to occur bending failure even more, the initial stiffness of the wall decreases, the overall ductility of the wall is improved and the walls tend to occur bending failure.

The previous studies do not involve the seismic performance of EBIMFCW under different shear-span ratios. Therefore, the paper studies the hysteresis behavior, ductility, stiffness degradation and energy dissipation performance of EBIMFCW under different shear-span ratios.

Purpose: This study aims to identify communication speech acts and transaction terms in online stores (Olshop) during live streaming on Facebook amid the COVID-19 pandemic and to understand communication patterns between sellers and buyers when shopping on Facebook live streaming in Indonesia.

The Need for Research: This research is motivated by the skill gap arising from increasing buying and selling transactions through live streaming on Facebook. Cultural and demographic shifts, along with the widespread availability of modern technologies and marketing 2.0 have resulted in the global population adopting social media at rates far beyond our use of the Internet, making a compelling case by example and analogy that social media has the potential to level the playing field and is effective in reaching their target market.

Methodology: The type of research is descriptive-qualitative using corpus data instruments. The data collection technique in this study was carried out by reading and observing the data and listening to speeches about buying and selling women’s equipment from various online stores on Facebook. Then select and sort the data designated as forms, strategies, and functions of speech acts in buying and selling transactions during live streaming on Facebook. The data analysis technique has three steps: (1) reducing the amount of data; (2) presenting the data; and (3) concluding.

Findings: The results show that there are four types of speech acts between sellers and buyers in the live-streaming online shop on Facebook, namely, assertive, directive, expressive, and commissive speech acts.