Mobile Live Video Streaming Optimization via Crowdsourcing Brokerage

Nowadays, people can enjoy a rich real-time sensing cognition of what they are interested in anytime and anywhere by leveraging powerful mobile devices such as smartphones. As a key support for the propagation of these richer live media contents, cellular-based access technologies play a vital role to provide reliable and ubiquitous Internet access to mobile devices. However, these limited wireless network channel conditions vary and fluctuate depending on weather, building shields, congestion, etc., which degrade the quality of live video streaming dramatically. To address this challenge, we propose to use crowdsourcing brokerage in future networks which can improve each mobile user's bandwidth condition and reduce the fluctuation of network condition. Further, to serve mobile users better in this crowdsourcing style, we study the brokerage scheduling problem which aims at maximizing the user's QoE (quality of experience) satisfaction degree cost-effectively. Both offline and online algorithms are proposed to solve this problem. The results of extensive evaluations demonstrate that by leveraging crowdsourcing technique, our solution can cost-effectively guarantee a higher quality view experience

Wind tunnel study on the pedestrian-level wind comfort in residential areas of Harbin

Pedestrian-level wind conditions in residential areas are closely related to the quality of urban residents' daily life. In this paper, seven representative building layouts of urban residential areas were summarized from actual residential areas of Harbin, and wind tunnel experiments were carried out to study the pedestrian-level wind comfort in these residential areas. The assessments of pedestrian wind comfort are performed by combining the wind tunnel results and long-term local wind statistics. The results show that the hybrid-type and the enclosed-type layouts can provide better pedestrian wind comfort than parallel-type layouts, and the building heights of residential areas need to be controlled in cities of severe cold regions

Aspects of New and Old Urban Parks Most Valued by Residents on Social Media: A Case Study in Hefei

The rapid development of new first-tier cities in China has led to potentially significant differences in residents’ environmental perceptions toward parks in new and old urban areas. However, there is currently a lack of relevant comparative research. Therefore, this study used the new first-tier city of Hefei as an example and selected the two most popular urban parks in the new and old downtown areas—Swan Lake Park and Xiaoyaojin Park. This study aimed to find out which aspects of the new and old city parks were the most valued by the residents by analysing their online comments on social media platforms. Based on the social media comments, quantitative and qualitative analyses were conducted to study residents’ perceptions and preferences and analyse residents’ activities and satisfaction. The research found the following: (1) There was consistency in the type of content in the downtown parks as perceived by the residents of the new and old urban areas. (2) For the old downtown Xiaoyaojin Park, the residents were more interested in the experience in terms of the recreation facilities and services but were less satisfied with the visitor capacity of the playground and the ticket price. For the new downtown Swan Lake Park, the residents were more interested in the experience in terms of the exercise facilities and venues and were worried about the safety of the venues. (3) The perceived environmental preferences of the residents in the old urban areas were mainly related to childhood activity venues, and the perceived environmental preferences of the residents in the new urban areas were mainly related to novelty activities. Based on the results, targeted suggestions were proposed for the development of characteristic resources, facility management and maintenance, and the renewal and renovation of recreational activities. Since social media analysis plays an important role in the construction of urban parks, the findings can help us to better understand residents’ lives, ensure that parks are designed for the happiness of the people, and develop more sustainable pathways for the design and management of urban areas

Landscape Configuration Effects on Outdoor Thermal Comfort across Campus—A Case Study

As a main place for student activities on campus, outdoor spaces have positive impacts on students’ physical and mental health. Namely, outdoor heat and comfort are of great significance to improve activity quality. Here, four unique outdoor spaces were studied to explore the varying effects on human thermal comfort during hot-summer and cold-winter periods. Distinct outdoor spaces (fully open, semi-open, semi-enclosed, and fully enclosed areas) from the southern campus of Anhui Jianzhu University were chosen. The PET was used as a metric for measuring thermal comfort and analyzing correlated spatiotemporal distributions. The results showed that outdoor thermal comfort was derived from multiple factors, including vegetation, underlying surface materials, building presence, and wind-heat environment. Notably, high correlations between Tmrt and thermal comfort were revealed, where such temperatures of places with trees or building shade were low; thus, PET was low. Further, Ws showed a significantly negative correlation with PET. Of the four outdoor space forms, the fully enclosed location had the lowest thermal comfort level, while the semi-enclosed spaces showed the highest level of body comfort. Therefore, semi-enclosed space (U-shaped) is recommended in campus planning and construction. Accordingly, an improved strategy was proposed based on experimental transformation for fully enclosed spaces. The thermal comfort after optimization was simulated to provide references for outdoor space thermal comfort improvement during seasonal extremes

Study on Outdoor Thermal Comfort in the Transitional Season of Hefei

In order to study the outdoor thermal comfort during the transition season in Hefei, a university in Hefei adopted a combination of field environmental measurements and questionnaires to study the changes in thermal sensation and thermal comfort of outdoor people before and after the transition season. The rankings of the effects of temperature, wind speed, humidity, and solar radiation on human thermal comfort were obtained through surveys, and the proportion of each parameter’s influence on human thermal comfort was analyzed. The relationship between thermal sensation and thermal comfort was analyzed, and the application was established through regression analysis Prediction model of thermal sensation in autumn and winter outdoor environment in Hefei area

Analysis and Discussion on the Design of Green Super High-rise Civil Buildings in Huangshan

With the accelerating urbanization process and the development of the construction industry, the role of green building design in architectural design is constantly reflected. The comprehensive implementation of green building is an important measure to promote China's energy-saving emission reduction and low-carbon city strategy. However, there are relatively few cases in which green building design is applied to super high-rise civil buildings, and in-depth research and data analysis must be carried out. The design points in green super high-rise civil buildings in Huangshan area were briefly summarized, and the actual cases of a green super high-rise civil building design in Huangshan City were analyzed, which is conducive to laying the foundation for the application of green building design to super high-rise civil buildings

Composition and Morphology Modulation of Bimetallic Nitride Nanostructures on Nickel Foams for Efficient Oxygen Evolution Electrocatalysis

Metal-nitrides-based electrocatalysts for efficient oxygen-evolution have been extensively studied as one of the most promising candidates to fulfil the demand for future energy-conversion and storage. Herein, a series of NixCo1−xO- and NixCo1−xN-based nanostructures on nickel foams were reported to show excellent activities for oxygen-evolution reaction. The catalysts were prepared and modulated rationally via a facile-hydrothermal method, followed by high-temperature calcination under air or nitrogen atmosphere. The optimal bimetallic-nitride catalyst Ni0.3Co0.7N shows a small overpotential of 268 mV at 20 mA cm−2, and a Tafel slope of 66 mV dec−1 with good stability. The enhanced OER-performance is ascribed to the synergetic effect of the unique morphology and the intrinsic catalytic property of the nanostructure after nitridation

Composition and Morphology Modulation of Bimetallic Nitride Nanostructures on Nickel Foams for Efficient Oxygen Evolution Electrocatalysis

Metal-nitrides-based electrocatalysts for efficient oxygen-evolution have been extensively studied as one of the most promising candidates to fulfil the demand for future energy-conversion and storage. Herein, a series of NixCo1−xO- and NixCo1−xN-based nanostructures on nickel foams were reported to show excellent activities for oxygen-evolution reaction. The catalysts were prepared and modulated rationally via a facile-hydrothermal method, followed by high-temperature calcination under air or nitrogen atmosphere. The optimal bimetallic-nitride catalyst Ni0.3Co0.7N shows a small overpotential of 268 mV at 20 mA cm−2, and a Tafel slope of 66 mV dec−1 with good stability. The enhanced OER-performance is ascribed to the synergetic effect of the unique morphology and the intrinsic catalytic property of the nanostructure after nitridation