42 research outputs found
Microclimate characteristics and multi-effect analysis of facade and rooftop agriculture based on in-situ observation and meta-analysis
Facade and rooftop agriculture has great potential in regulating urban local microclimate, building energy conservation and carbon emission reduction. This study aims to address the limitation that the existing studies lack multi-effect simulations of integrated implementation of facade and rooftop agriculture. It takes into account the variability and complexity of thermal coefficients in planting layers during the simulations. By analyzing in-situ observations, the study examines the regulatory impact of integrated agriculture on urban microclimate. Furthermore, it uses observed data instead of DeST temperature database data to simulate the energy-saving effect and carbon emission reduction. In order to analyse the average economic efficiency of rooftop and facade agriculture in China, the study conducts a meta-analysis of existing cases in China. The results of the study are as follows: (1) The thermal insulation efficiency of the facade and rooftop integrated agriculture varies with weather conditions and diurnal variations. It reaches the strongest (1.68°C) on sunny days and around noon, (2) The integrated implementation of facade and rooftop agriculture on a normal home building in Changsha can save a total of 12,226.30 kW·h (5%) of electricity per year, and thus reducing 2,809.26 kg of carbon emissions, and (3) Based on meta-analysis and LCA calculation, the average net present value of the project in China for 40a is RMB -937712.18. The economic efficiency needs to be optimized. The results of this study reveal the ideal ecological benefits of facade and rooftop agriculture and the economic efficiency that hinders their implementation, providing a theoretical basis for building energy conservation and renovation, and the economic efficiency optimization in the regions with hot summer and cold winter
CatNorth: An Improved Gaia DR3 Quasar Candidate Catalog with Pan-STARRS1 and CatWISE
A complete and pure sample of quasars with accurate redshifts is crucial for
quasar studies and cosmology. In this paper, we present CatNorth, an improved
Gaia DR3 quasar candidate catalog with more than 1.5 million sources in the
3 sky built with data from Gaia, Pan-STARRS1, and CatWISE2020. The XGBoost
algorithm is used to reclassify the original Gaia DR3 quasar candidates as
stars, galaxies, and quasars. To construct training/validation datasets for the
classification, we carefully built two different master stellar samples in
addition to the spectroscopic galaxy and quasar samples. An ensemble
classification model is obtained by averaging two XGBoost classifiers trained
with different master stellar samples. Using a probability threshold of
in our ensemble classification model and an
additional cut on the logarithmic probability density of zero proper motion, we
retrieved 1,545,514 reliable quasar candidates from the parent Gaia DR3 quasar
candidate catalog. We provide photometric redshifts for all candidates with an
ensemble regression model. For a subset of 89,100 candidates, accurate
spectroscopic redshifts are estimated with the Convolutional Neural Network
from the Gaia BP/RP spectra. The CatNorth catalog has a high purity of > 90%
while maintaining high completeness, which is an ideal sample to understand the
quasar population and its statistical properties. The CatNorth catalog is used
as the main source of input catalog for the LAMOST phase III quasar survey,
which is expected to build a highly complete sample of bright quasars with .Comment: 24 pages, 13 figures, submitted to AAS journals. Table 4 (The
CatNorth quasar candidate catalog) is available at
https://nadc.china-vo.org/res/r101313
High-resolution spatiotemporal transcriptome mapping of tomato fruit development and ripening
Tomato (Solanum lycopersicum) is an established model for studying fruit biology; however, most studies of tomato fruit growth and ripening are based on homogenized pericarp, and do not consider the internal tissues, or the expression signatures of individual cell and tissue types. We present a spatiotemporally resolved transcriptome analysis of tomato fruit ontogeny, using laser microdissection (LM) or hand dissection coupled with RNA-Seq analysis. Regulatory and structural gene networks, including families of transcription factors and hormone synthesis and signaling pathways, are defined across tissue and developmental spectra. The ripening program is revealed as comprising gradients of gene expression, initiating in internal tissues then radiating outward, and basipetally along a latitudinal axis. We also identify spatial variations in the patterns of epigenetic control superimposed on ripening gradients. Functional studies elucidate previously masked regulatory phenomena and relationships, including those associated with fruit quality traits, such as texture, color, aroma, and metabolite profiles.Peer reviewe
Study on Wear and Fatigue Performance of Two Types of High-Speed Railway Wheel Materials at Different Ambient Temperatures
The wear and fatigue behaviors of two newly developed types of high-speed railway wheel materials (named D1 and D2) were studied using the WR-1 wheel/rail rolling–sliding wear simulation device at high temperature (50 °C), room temperature (20 °C), and low temperature (−30 °C). The results showed that wear loss, surface hardening, and fatigue damage of the wheel and rail materials at high temperature (50 °C) and low temperature (−30 °C) were greater than at room temperature, showing the highest values at low temperature. With high Si and V content refining the pearlite lamellar spacing, D2 presented better resistance to wear and fatigue than D1. Generally, D2 wheel material appears more suitable for high-speed railway wheels
The Influence of Top Managers on Environmental Information Disclosure: The Moderating Effect of Company’s Environmental Performance
Abundant extant literature emphasizes the impact of board members attributes’ influence on environmental information disclosure. Considering the voluntary nature of environmental information disclosure, executives have strong managerial discretion when they make such decisions, so this article focuses on top managers’ influence on environmental information disclosure. We hypothesize that top managers’ educational background and age will affect companies’ environmental decision. The hypotheses are verified with the data from Chinese listed manufacturing companies. As the results show, a Master of Business Administration (MBA) educational background and average age of top managers positively affect environmental information disclosure, while the impact of legal educational background is negative. The company’s environmental performance plays a U-shaped moderating effect on the relationship between MBA educational background and environmental information disclosure
Estimation of COVID-19 Transmission and Advice on Public Health Interventions
At the end of 2019, an outbreak of the novel coronavirus (COVID-19) made a profound impact on the country’s production and people’s daily lives. Up until now, COVID-19 has not been fully controlled all over the world. Based on the clinical research progress of infectious diseases, combined with epidemiological theories and possible disease control measures, this paper establishes a Susceptible Infected Recovered (SIR) model that meets the characteristics of the transmission of the new coronavirus, using the least square estimation (LSE) method to estimate the model parameters. The simulation results show that quarantine and containment measures as well as vaccine and drug development measures can control the spread of the epidemic effectively. As can be seen from the prediction results of the model, the simulation results of the epidemic development of the whole country and Nanjing are in agreement with the real situation of the epidemic, and the number of confirmed cases is close to the real value. At the same time, the model’s prediction of the prevention effect and control measures have shed new light on epidemic prevention and control
Green Product Innovation and Firm Performance: Assessing the Moderating Effect of Novelty-Centered and Efficiency-Centered Business Model Design
Motivated by government policies and decision-makers’ opportunity perception, many firms have invested in green product innovation. The effect of this type of innovation has been analyzed in extant literature thoroughly, but how to improve innovator’s economic performance is still under-researched. When considering this research gap, the business model theory is used in this paper. An empirically based and testable framework is developed. Using survey data from 231 traditional manufacturing firms in China, these hypotheses are tested. The results show that novelty-centered and efficiency-centered business model design themes all play a moderating effect on the relationship between green product innovation and firm performance, while a fit between green product innovation and novelty-centered design theme is better for firm performance