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Wavelet Analysis on Temperature and Precipitation Changes in Dabie Mountain of West Anhui
The wavelet analysis method is applied to analysis of multi-level time change characteristics of temperature and precipitation in Dabie Mountain based on the meteorological observation data of five stations in Dabie Mountain from 1960 to 2013. According to results, the temperature shows oscillation periods of 22 years and 10 years in Dabie Mountain, West Anhui. While the precipitation shows an oscillation period of26 years. The change relationships of temperature and precipitation are not the same based on different time scales. From the scale of 3 years, to 10 years and 20 years, the out-of phase becomes weaker. The tendency of consistence appears gradually.
Journal Article
The Different Ability of Free Body Diagram (FBD) Representation In Newton's Law Topic Based on Students' Thinking Style
This study aims to determine the different ability of free body diagram (FBD) representation in Newton's Law based onstudents' thinking style. The subject of this research is the students of 10th grade from science class at state senior high school 1 of Prembun. The data analized is the results of cognitive test and students' thinking character questionnaire. The data were analyzed by using quantitative method. Based on the result, can be concluded that there is no difference between the ability of free body diagrams representating with a category sequential concrete, sequential abstract, random concrete and random abstract, which in the four categories of thinking styles included in the criteria need improvement.
Journal Article
Research on Dynamic Political Sentiment Polarity Analysis of Specific Group Twitter Based on Deep Learning Method
The article introduce a method to analyzing the dynamic political sentiment polarity of American politicians' tweets within a fixed period of time to assist analysts in judging the direction of American politics and the future trend of China-US relations. This research is applied in the field of think tanks or intelligence analysis. The service targets are intelligent analysts, and the data is the tweet text data sent by a specific group in a fixed time period. We propose an architecture that combines multiple deep learning models and use a dedicated tweet data set to construct a specific group to obtain an sentiment polarity multi-classifier, and then introduce the time characteristics of tweets, and finally obtain the dynamic political sentiment polarity of politicians. The US politician tweets data set proposed in this article verifies that the proposed comprehensive architecture is better than traditional deep learning methods in this task, and the accuracy of the classifier verification set reaches 80.66%. According to the sentiment polarity judgments of 20 US governors and senators, the success rate is 75%. The analysis of individual dynamic political sentiment polarity can provide effective help and intelligence support for analysts. The method in this paper effectively uses a variety of deep learning techniques to assist analysts to obtain more accurate dynamic political sentiment polarity from massive Twitter text data.
Journal Article
Acceleration of phenological advance and warming with latitude over the past century
In the Northern Hemisphere, springtime events are frequently reported as advancing more rapidly at higher latitudes, presumably due to an acceleration of warming with latitude. However, this assumption has not been investigated in an analytical framework that simultaneously examines acceleration of warming with latitude while accounting for variation in phenological time series characteristics that might also co-vary with latitude. We analyzed 743 phenological trend estimates spanning 86 years and 42.6 degrees of latitude in the Northern Hemisphere, as well as rates of Northern Hemisphere warming over the same period and latitudinal range. We detected significant patterns of co-variation in phenological time series characteristics that may confound estimates of the magnitude of variation in trends with latitude. Notably, shorter and more recent time series tended to produce the strongest phenological trends, and these also tended to be from higher latitude studies. However, accounting for such variation only slightly modified the relationship between rates of phenological advance and latitude, which was highly significant. Furthermore, warming has increased non-linearly with latitude over the past several decades, most strongly since 1998 and northward of 59°N latitude. The acceleration of warming with latitude has likely contributed to an acceleration of phenological advance along the same gradient.
Journal Article
Ultralight Metallic Microlattices
Ultralight (< 10 milligrams per cubic centimeter) cellular materials are desirable for thermal insulation; battery electrodes; catalyst supports; and acoustic, vibration, or shock energy damping. We present ultralight materials based on periodic hollow-tube microlattices. These materials are fabricated by starting with a template formed by self-propagating photopolymer waveguide prototyping, coating the template by electroless nickel plating, and subsequently etching away the template. The resulting metallic microlattices exhibit densities ρ > 0.9 milligram per cubic centimeter, complete recovery after compression exceeding 50% strain, and energy absorption similar to elastomers. Young's modulus Å scales with density as E ~ p², in contrast to the £ ~ p³ scaling observed for ultralight aerogels and carbon nanotube foams with stochastic architecture. We attribute these properties to structural hierarchy at the nanometer, micrometer, and millimeter scales.
Journal Article
The Demographic Transition of Yunnan Province and its Influence on the Ecological Environment since Bronze Age to Modern Times
Abstract
Driven by the Industrial Revolution, the relationship between population and ecological environment is found an obvious brand new look as science technology takes part in human production and life as well as economic activities in modern times. It depicts a more distinct time characteristic than ever before. Consequently, the influence of Yunnan’s demographic transition on ecological environment is discussed under this period from two angles. One is demographic situation, and the other is human activities. The results showed that such negative impacts were undoubtedly caused by static demographic situation and dynamic human activities. And these impacts have become more profound with the development of science and technology.
Journal Article
Preparation and characterization of graphene oxide paper
Free-standing paper-like or foil-like materials are an integral part of our technological society. Their uses include protective layers, chemical filters, components of electrical batteries or supercapacitors, adhesive layers, electronic or optoelectronic components, and molecular storage. Inorganic 'paper-like' materials based on nanoscale components such as exfoliated vermiculite or mica platelets have been intensively studied and commercialized as protective coatings, high-temperature binders, dielectric barriers and gas-impermeable membranes4,5. Carbon-based flexible graphite foils composed of stacked platelets of expanded graphite have long been used in packing and gasketing applications because of their chemical resistivity against most media, superior sealability over a wide temperature range, and impermeability to fluids. The discovery of carbon nanotubes brought about bucky paper, which displays excellent mechanical and electrical properties that make it potentially suitable for fuel cell and structural composite applications. Here we report the preparation and characterization of graphene oxide paper, a free-standing carbon-based membrane material made by flow-directed assembly of individual graphene oxide sheets. This new material outperforms many other paper-like materials in stiffness and strength. Its combination of macroscopic flexibility and stiffness is a result of a unique interlocking-tile arrangement of the nanoscale graphene oxide sheets.
Journal Article
Risk identification of calibration laboratories
Abstract
The article is devoted to the identification, ranking and quantitative analysis of the risks that affect the quality of calibration work in the calibration laboratory. The paper used the brainstorming technique, the Ishikawa chart, and the ranking method for research. The results are represented by the Pareto chart. The ranked list was compiled based on the statistical data of the calibration laboratory. The ranked list was used as assessment criteria of risk.
Journal Article