Diachronic semantic change in language influences, and is constrained by, how people use and learn language

While it has long been understood that the human mind evolved to learn language, recent studies have begun to ask the inverted question: How has language evolved under the cognitive constraints of its users and become more learnable over time? In this paper, we explored how the semantic change of English words is shaped by the way humans acquire and process language. In Study 1, we quantified the extent of semantic change over the past 200 years and found that meaning change is more likely for words that are acquired later in life and are more difficult to process. We argue that it is human cognition that constrains the semantic evolution of words, rather than the other way around, because historical meanings of words were not easily accessible to people living today, and therefore could not have directly influenced how they learn and process language. In Study 2, we went further to show that semantic change, while bringing the benefit of meeting communicative needs, is cognitively costly for those who were born early enough to experience the change: Semantic change between 1970 and 2000 hindered processing speeds among middle-aged adults (ages 45-55) but not in younger adults (ages <25) in a semantic decision task. This hampering effect may have, in turn, curbed the rate of semantic change so that language does not change too fast for the human mind to catch up. Taken together, our research demonstrates that semantic change is shaped by processing and acquisition patterns across generations of language users

Water discharge and sediment flux changes in the Lower Mekong River

International audienceThe Lower Mekong River has witnessed extremely low water levels over the past few years. There is speculation that the changes are a consequence of the construction and operation of the Chinese cascade dams in the upper part of the Mekong main stream, the Lancang River. Dam construction on upper streams can produce a series of induced effects downstream, particularly in terms of water, sediment, channel and ecological changes. The infilling of the Manwan reservoir in 1992 caused water levels to fall to record lows in various parts of the Mekong River, and sediment concentration values decreased similarly. Analyses of discharge and sediment flux at various gauging stations on the Lower Mekong River have indicated a disruption in water discharge, water fluctuations and sediment transport downstream of the Manwan Dam, after its reservoir was infilled in 1992. Dry season flows showed a declining trend, and water level fluctuations in the dry season increased considerably in the post-dam (1993?2000) period. Monthly suspended sediment concentration (SSC) has also decreased significantly in several gauging stations in the post-dam period. The estimation of sediment flux is challenging since the measurements of SSC were sporadic. Our estimation based on the available data indicated that the areas along the upper-middle and lowermost reaches of the Mekong River have experienced a decline in sediment flux, possibly due to sedimentation in the Manwan Dam. However, the decrease is only statistically significant at Chiang Saen. Areas located in the mid-length of the river show less sensitivity to the operation of the Manwan Dam, as sediment fluxes have remained stable or even increased in the post-dam period

Cognitive network science: A review of research on cognition through the lens of network representations, processes, and dynamics

10.1155/2019/2108423Complexity2019210842

Optimal boundary control of a linear parabolic evolution system

We consider the optimal boundary control of a linear parabolic boundary value problem. Firstly, the problem is formulated as an optimization problem with the system state governed by a parabolic partial differential equation. Based on the formulation for the variation of the cost functional, a gradient-type optimization technique utilizing the finite element method is then developed to solve the constrained optimization problem. Finally, a numerical example is given and the results show that the method of solution is robust

STUDENTS’ QUESTIONS IN INQUIRY-BASED CHEMISTRY CLASSROOMS

Questioning plays an important part in the teaching and learning science. Previous research has extensively focused on teachers’ questions compared to students’ questions. Research of students’ questions is vital as it shows how students think and their understanding of a content studied. Hence, this research focuses on students’ questions, types of questions asked and the sequence(s) after students’ question. Twenty three chemistry teachers and their students of national secondary schools were involved in this study. Ninety two chemistry lessons were observed, audio and video recorded. Transcript of the lessons showed that students’ questions were mainly related to content or science process skills as emphasised in inquiry teaching and learning. However, most questions asked by students were low order closed questions. The sequence after students’ questions with the highest percentage (83.33%) was IR (Initiation from student, followed by teachers’ response). This sequence showed that chemistry teachers in this study did not display inquiry-based questioning characteristics because in inquiry teaching, teachers should avoid responding to students’ questions. Instead, they should provide opportunities for students to respond to their friends’ questions. Hence, teachers should move towards student initiated inquiry, where students ask higher order thinking questions and increasing the interaction among the students

Quantifying appearance retention in carpets using geometrical local binary patterns

Quality assessment in carpet manufacturing is performed by humans who evaluate the appearance retention (AR) grade on carpet samples. To quantify the AR grades objectively, different research based on computer vision have been developed. Among them Local Binary Pattern (LBP) and its variations has shown promising results. Nevertheless, the requirements of quality assessment on a wide range of carpets have not been met yet. One of the difficulties is to distinguish between consecutive AR grades in carpets. For this, we adopt an extension of LBP called Geometrical Local Binary Patterns (GLBP) that we recently proposed. The basis of GLBP is to evaluate the grey scale differences between adjacent points defined on a path in a neighbourhood. Symmetries of the paths in the GLBPs are evaluated. The proposed technique is compared with an invariant rotational mirror based LBP technique. The results show that the GLBP technique performs better to distinguish consecutive AR grades in carpets

Do Indian economic activities impact ASEAN-5 stock markets?

This study examines the dynamic linkages of ASEAN-5 with India based on a multivariate framework. DCC-MGARCH model was used to assess the presence of contagion effects and herding behaviour, indicated by the dynamic conditional correlations. The var -Granger causality test was employed to capture the direction of dynamic volatility transmission at the short run. Findings showed that the dynamic correlation of ASEAN-5 stock markets with Indian economy is in par with the U.S. and Japan. The simultaneous sudden spike in Dynamic Conditional Correlation between India and ASEAN-5 and followed by immediate reversal to decreasing Dynamic Conditional Correlation in 2009 indicate a contagion effect and herding behaviour which coincided with European sovereign debt crisis. The immediate reversal back to decreasing Dynamic Conditional Correlation suggests that both countries are hardly contagious by external crisis. In the short run, there is no volatility spillover from Indian economic activities to ASEAN-5 stock markets but there is volatility spillover from stock markets of Indonesia and Singapore to Indian economic activities. Trade policies, economic crises and economic liberalisation play significant roles in shaping the structure of the dynamic volatility correlations between the studied markets. This study reveals that ASEAN-5 has become preferred markets for the diversification of stock portfolio for India in the short run

Drying Characteristics and Product Quality of Lemon Slices Dried with Hot Air Circulation Oven and Hybrid Heatpump Dryers

In this research, drying characteristics and product quality of Coulomb-force-assisted heatpump and oven dried lemon slices were studied. Lemon slices with 3 mm thickness each, were dried using oven and Coulomb-force-assisted-heatpump dryer with and without auxiliary heater at different drying conditions. It was found that the drying rate of the lemon slices dried by all drying methods showed only falling rate states, which indicates the drying kinetics were controlled by internal moisture diffusion. Oven drying of lemon slices at 60°C showed the highest drying rate among all, followed by oven dried slices at 50°C, Coulomb-force-heater-assisted-heatpump (CF-HT-HP) dried slices at 31°C, Coulomb-force-assisted-heatpump (CF-HP) dried slices at 22°C, oven dried slices at 40°C and heatpump dried slices at 22°C. The average effective moisture diffusivity value for the slices dried with these drying methods was found in the range of 16.2 to 63.8´10-4 mm2min-1. In terms of quality assessment, CF-HP dried lemon slices retained the highest amount of Vitamin C as compared to the lemon slices dried by other drying methods. However, it retained relatively lower amount of total phenolic content (TPC) as compared to oven dried products. Among of all, CF-HP drying method produced dried lemon slices with the highest Vitamin C (6.74 mg AA / g dry weight) whereas oven dried lemon slices at 50°C preserved most of the TPC in the dried slices, which recorded as 13.76 mg GA / g dry weight

Nanoscale broadband transmission lines for spin qubit control

The intense interest in spin-based quantum information processing has caused an increasing overlap between two traditionally distinct disciplines, such as magnetic resonance and nanotechnology. In this work we discuss rigourous design guidelines to integrate microwave circuits with charge-sensitive nanostructures, and describe how to simulate such structures accurately and efficiently. We present a new design for an on-chip, broadband, nanoscale microwave line that optimizes the magnetic field driving a spin qubit, while minimizing the disturbance on a nearby charge sensor. This new structure was successfully employed in a single-spin qubit experiment, and shows that the simulations accurately predict the magnetic field values even at frequencies as high as 30 GHz.Comment: 18 pages, 8 figures, 1 table, pdflate