341 research outputs found
Cultivating Empathy: New Perspectives on Educating Business Leaders
Beyond rules, procedures, and manuals lie relationships. Jettisoning a formal hierarchical company structure allows all levels of management and employees to positively interact – this is where the key driver of “empathy” is so critical to continue building these relationships and molding a common organizational purpose
Porous calcium phosphate ceramics prepared by coating polyurethane foams with calcium phosphate cements
Porous calcium phosphates have important biomedical applications such as bone defect fillers, tissue engineering scaffolds, and drug delivery systems. While a number of methods to produce the porous calcium phosphate ceramics have been reported, this study aimed to develop a new fabrication method. The new method involved the use of polyurethane foams to produce highly porous calcium phosphate cements (CPCs). By firing the porous CPCs at 1200 degrees Celsius, the polyurethane foams were burnt off and the CPCs prepared at room temperature were converted into sintered porous hydroxyapatite-based calcium phosphate ceramics. The sintered porous calcium phosphate ceramics could then be coated with a layer of the CPC at room temperature, resulting in high porosity, high pore interconnectivity, and controlled pores size
Uniqueness in determining rectangular grating profiles with a single incoming wave (Part II): TM polarization case
This paper is concerned with an inverse transmission problem for recovering
the shape of a penetrable rectangular grating sitting on a perfectly conducting
plate. We consider a general transmission problem with the coefficient
\lambda\neq 1 which covers the TM polarization case. It is proved that a
rectangular grating profile can be uniquely determined by the near-field
observation data incited by a single plane wave and measured on a line segment
above the grating. In comparision with the TE case (\lambda=1), the wave field
cannot lie in H^2 around each corner point, bringing essential difficulties in
proving uniqueness with one plane wave. Our approach relies on singularity
analysis for Helmholtz transmission problems in a right-corner domain and also
provides an alternative idea for treating the TE transmission conditions which
were considered in the authors' previous work [Inverse Problem, 39 (2023):
055004.
Highly Stable and Active Catalyst for Sabatier Reactions
Highly active Ru/TiO2 catalysts for Sabatier reaction have been developed. The catalysts have shown to be stable under repeated shutting down/startup conditions. When the Ru/TiO2 catalyst is coated on the engineered substrate Fe-CrAlY felt, activity enhancement is more than doubled when compared with an identically prepared engineered catalyst made from commercial Degussa catalyst. Also, bimetallic Ru-Rh/TiO2 catalysts show high activity at high throughput
An activity-based spatial-temporal community electricity vulnerability assessment framework
The power system is among the most important critical infrastructures in
urban cities and is getting increasingly essential in supporting people s daily
activities. However, it is also susceptible to most natural disasters such as
tsunamis, floods, or earthquakes. Electricity vulnerability, therefore, forms a
crucial basis for community resilience. This paper aims to present an
assessment framework of spatial-temporal electricity vulnerability to support
the building of community resilience against power outages. The framework
includes vulnerability indexes in terms of occupant demographics, occupant
activity patterns, and urban building characteristics. To integrate factors in
these aspects, we also proposed a process as activity
simulation-mapping-evaluation-visualization to apply the framework and
visualize results. This framework can help planners make an effective
first-time response by identifying the most vulnerable areas when a massive
power outage happens during natural disasters. It can also be integrated into
community resilience analysis models and potentially contributes to effective
disaster risk managementComment: to be published in Proceedings of the 5th International Conference on
Building Energy and Environmen
Community Time-Activity Trajectory Modelling based on Markov Chain Simulation and Dirichlet Regression
Accurate modeling of human time-activity trajectory is essential to support
community resilience and emergency response strategies such as daily energy
planning and urban seismic vulnerability assessment. However, existing modeling
of time-activity trajectory is only driven by socio-demographic information
with identical activity trajectories shared among the same group of people and
neglects the influence of the environment. To further improve human
time-activity trajectory modeling, this paper constructs community
time-activity trajectory and analyzes how social-demographic and built
environment influence people s activity trajectory based on Markov Chains and
Dirichlet Regression. We use the New York area as a case study and gather data
from American Time Use Survey, Policy Map, and the New York City Energy & Water
Performance Map to evaluate the proposed method. To validate the regression
model, Box s M Test and T-test are performed with 80% data training the model
and the left 20% as the test sample. The modeling results align well with the
actual human behavior trajectories, demonstrating the effectiveness of the
proposed method. It also shows that both social-demographic and built
environment factors will significantly impact a community's time-activity
trajectory. Specifically, 1) Diversity and median age both have a significant
influence on the proportion of time people assign to education activity. 2)
Transportation condition affects people s activity trajectory in the way that
longer commute time decreases the proportion of biological activity (eg.
sleeping and eating) and increases people s working time. 3) Residential
density affects almost all activities with a significant p-value for all
biological needs, household management, working, education, and personal
preference.Comment: to be published in Computers, Environment and Urban Syste
Impacts of Climate Variability and Human Activities on the Changes of Runoff and Sediment Load in a Catchment of the Loess Plateau, China
The objectives of this study are to investigate the changes of runoff and sediment load and their potential influencing factors in the Huangfuchuan catchment. The Mann-Kendall test and accumulative anomaly methods were, respectively, applied to examine the changing trends and abrupt changes. Both annual runoff and sediment load demonstrated significant reduction (p<0.05) with decreasing rates of −3.2 × 106 m3/a and −1.09 Mt/a, respectively. The abrupt changes were detected in 1979 and 1996 for the runoff and sediment load. All the runoff and sediment indices (runoff, sediment load, runoff coefficient, and sediment concentration) exhibited remarkable reduction (p<0.01). The climate variability contributed 24.4% and 25.1% during 1980–1996 and 1997–2010 to annual runoff decrease, respectively, and human activities accounted for the remaining 75.6% and 74.9%. In contrast, changes in precipitation accounted for 43.5% and 20.2% of sediment load reduction during 1980–1996 and 1997–2010, whereas the human activities contributed 56.5% and 79.8%, respectively. The relative contributions from climate variability and human activities to runoff and sediment load changes at annual scale were different from that at flood season scale. Results suggested the dominant role of soil and water conservations in the variation of runoff and sediment load in the catchment
Hydrodeoxygenation of Methyl Laurate over Ni Catalysts Supported on Hierarchical HZSM-5 Zeolite
The hierarchical HZSM-5 zeolite was prepared successfully by a simple NaOH treatment method. The concentration of NaOH solution was carefully tuned to optimal the zeolite acidity and pore structure. Under NaOH treatment conditions, a large number of mesopores, which interconnected with the retained micropores, were created to facilitate mass transfer performance. There are very good correlations between the decline of the relative zeolite crystallinity and the loss of micropores volume. The Ni nanoclusters were uniformly confined in the mesopores of hierarchical HZSM-5 by the excessive impregnation method. The direct deoxygenation in N2 and hydrodeoxygenation in H2 of the methyl laurate were compared respectively over the Ni/HZSM-5 catalysts. In the N2 atmosphere, the deoxygenation rate of the methyl laurate on the Ni/HZSM-5 catalyst is relatively slow. In the presence of H2, the synergistic effect between the hydrogenation function of the metal and the acid function of the zeolite supports can make the deoxygenation level more obvious. The yield of hydrocarbon products gradually reached the maximum with the appropriate treatment concentration of 1M NaOH, which could be attributed to the improved mass transfer in the hierarchical HZSM-5 supports
Satellite-like CdS nanoparticles anchoring onto porous NiO nanoplates for enhanced visible-light photocatalytic properties.
Novel CdS/NiO nanocomposites assembled by satellite-like CdS nanoparticles anchoring onto porous NiO nanoplates have been fabricated by a step synthesis process, which involves a chemical bathing method followed by a heat treatment, and a microwave-assisted aqueous chemical reaction. The structure and photocatalytic properties of products were characterized by various techniques. More significantly, benefiting from the synergistic effect of CdS/NiO heterojunction, the as-prepared CdS/NiO architectures exhibited superior photocatalytic activity for decolorization of Congo red. The degradation rate on CdS/NiO nanocomposites achieves about 3.5 times higher than that of pure CdS nanocrystals under visible light irradiation for 30 min, suggesting a promising application in water purification.This work was supported by the Key Projects of Support Program for Outstanding Young Talents of Anhui Province (gxyqZD2016151), the Natural Science Foundation of Anhui Province (1808085MB40), the Program of Study Abroad for Excellent Young Scholar of Anhui Province (gxfxZD2016221), the Natural Science Foundation of Anhui Province Educational Committee (KJ2014ZD08, KJ2015A145), and the Special Foundation for Scientists of Hefei University (15CR06)
Kooperativna evolucija za kvalitetno pružanje usluga u paradigmi Interneta stvari
To facilitate the automation process in the Internet of Things, the research issue of distinguishing prospective services out of many “similar” services, and identifying needed services w.r.t the criteria of Quality of Service (QoS), becomes very important. To address this aim, we propose heuristic optimization, as a robust and efficient approach for solving complex real world problems. Accordingly, this paper devises a cooperative evolution approach for service composition under the restrictions of QoS. A series of effective strategies are presented for this problem, which include an enhanced local best first strategy and a global best strategy that introduces perturbations. Simulation traces collected from real measurements are used for evaluating the proposed algorithms under different service composition scales that indicate that the proposed cooperative evolution approach conducts highly efficient search with stability and rapid convergence. The proposed algorithm also makes a well-designed trade-off between the population diversity and the selection pressure when the service compositions occur on a large scale.Kako bi se automatizirali procesi u internetu stvati, nužno je rezlikovati bitne usluge u moru sličnih kao i identificirati potrebne usluge u pogledu kvalitete usluge (QoS). Kako bi doskočili ovome problemu prdlaže se heuristička optimizacija kao robustan i efikasan način rješavajne kompleksnih problema. Nadalje, u članku je predložen postupak kooperativne evolucije za slaganje usluga uz ograničenja u pogledu kvalutete usluge. Predstavljen je niz efektivnih strategija za spomenuti problem uključujući strategije najboljeg prvog i najboljeg globalnog koje unose perturbacije u polazni problem. Simulacijski rezultati kao i stvarni podatci su korišteni u svrhu evaluacije prodloženog algoritma kako bi se osigurala efikasna pretraga uz stabilnost i brzu konvergenciju. Predloženi algoritam tako.er vodi računa o odnosu izme.u različitosti populacije i selekcijskog pritiska kada je potrebno osigurati slaganje usluga na velikoj skali
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