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41.
This essay paper focuses on how the idea and use of technology is gradually reorganizing not only the structural arrangements but also redefining relationships and relational patterns. In particular reference to new technological applications and sites that are increasingly used by people for networking and bonding, there is a macro-discourse of being and staying connected through technology. Such platforms assume an easy access or an imagined availability of the other person at all times. Such availability also assumes psychological availability of the person, despite any personal circumstances he/she may be in. Experiencing the compressed space and time has given birth to the debate of quality of life and relations surrounding it vs. the constant flux of technology that restricts the psychological freedom while facilitating a structural freedom to communicate. Technology is an artifact that not only symbolizes values of ease and convenience but also has the potential to affect the deeper assumptions and values people hold about life and relationships. Thus, it mediates our personal, social and organizational realities, pushing us to live in dual worlds. 相似文献
42.
Yu Liu Yizhen Huang Zheming Wang Shihai Cai Beiwei Zhu Xiuping Dong 《International Journal of Food Science & Technology》2021,56(10):4959-4969
Aquatic products are one of the most important foods with plenty of high-quality protein, unsaturated fatty acids (EPA, DHA), a variety of minerals and other essential nutrients. However, the bad smell of fish, such as fishy smell and earthy smell, restricts its production and consumption. The main fishy odour substances from freshwater fish and marine fish are different. The geosmin and 2-methylisobomeol are the main compounds in freshwater fish, and aldehydes, alcohols and ketones are found in most marine fish. The odour compounds can come from environment like water, feed and alga, enzymolysis and oxidative reactions of protein and lipid. Thus, it is necessary to remove or inhibit odour by managing farming environment like improving water quality, using physical method like adding some substance to cover the bad smell and using some chemical or biological method to prevent enzymolysis or oxidation. Therefore, knowing the composition of fishy substances and understanding their production pathways will play an important role in suppressing fishy substances and improving the competitiveness of consumer production. Besides, it could provide new ideas for innovative deodorising methods. 相似文献
43.
This study aims to explore the impact of light-duty passenger (LdP) electric vehicle (EV) charging on the Portuguese national load profile (LP) in 2030. The goal is to identify EV charging strategies that enable a sustainable configuration of the Portuguese LP under different potential levels of LdP EV penetration in 2030. The research offers Portuguese utilities and policymakers information regarding potential threats and solutions of different EV charging strategies on the national grid infrastructure in 2030. Furthermore, it proposes a methodology that can also be adopted in other countries to analyse similar problems. Low, medium, and high penetration scenarios were designated based on the number of LdP EVs. The low and medium penetration scenarios indicate that an intelligent grid is not necessary to perform charging activities. However, coordinating EV charging in the evening via a smart grid (SG) is imperative in the high penetration scenario, as unsustainable levels of power demand will otherwise be reached, compared with the current production and distribution capacity. Moreover, morning charging sessions must also be addressed, as they may induce new peaks of daily consumption given the significant amount of charging activity taking place within that period. 相似文献
44.
《Information & Management》2022,59(5):103216
Even using simple techniques like taking the stairs, many individuals struggle to maintain the motivation to be physically active. Health gamification systems can aid this goal by providing points earned through exercise that are redeemable for tangible extrinsic rewards. Using self-determination theory, we conduct research on one such system and investigate rewards’ effectiveness to promote exercise considering reward value, redemption frequency patterns, and fitness levels. We find that rewards do significantly increase activity levels, and this effect is larger for advanced users who redeem multiple times for higher value rewards. We close by offering future research avenues and advice to optimize reward portfolios. 相似文献
45.
《International Journal of Hydrogen Energy》2022,47(15):9127-9138
In this paper, a numerical analysis of the production of hydrogen via autothermal (ATR) steam methane reforming (SMR) is presented. The combustion reaction occurs over a Pt/Al2O3 catalyst, and the reforming reaction is operated using a Ni/Al2O3 catalyst inside the same cylindrical channel. A novel configuration with18 catalytic-bed macro-patterns alternately mounted, referred to as SDB, is designed and compared with the catalytic dual-bed reactor (conventional configuration), referred to as CDB, at the same operating temperature and pressure conditions of 900 °C and 14 bars, respectively. The results showed that hydrogen yield was improved by 4.5% compared to the conventional configuration, while a decrease of 67 °C of the highest temperature was noticed. Meanwhile, the methane conversion was 63.73% and 65.44% for the CDB and SDB configurations, respectively. Furthermore, the length of the reactor can be decreased by 27%, keeping the same hydrogen yield at the outlet of the conventional reactor, indicating a potential reduction in hydrogen cost. 相似文献
46.
为使机器鱼的顶球兼备精确性以及在鱼脱离预定轨道的情况下尽可能使水球朝有利于我方进攻方向偏离,提出一种精确与模糊协作的顶球策略。在分析以往顶球算法的基础上,设计一种以水球与目标点连线为基准的区域划分,综合考虑理想情况以及水中各种复杂因素影响后的鱼、球以及目标点的相对位置和几何关系,合理组合路径规划算法和动作决策算法,并以实例在符合路径规划条件和不符合路径规划的条件下进行测试。实验结果表明:该算法能最大限度地利用机器鱼目前所处的环境,使机器鱼的顶球兼备精确性和模糊性。 相似文献
47.
Mary W. Stoertz Heather Bourne Christa Knotts Matthew M. White 《Mine Water and the Environment》2002,21(2):60-72
Isolated headwater streams in mined watersheds may have good water quality and fish habitat, yet be disconnected from immigration
sources by stream segments impaired by acid mine drainage (AMD). Studies of fish and macroinvertebrate communities, habitat,
and a number of hydrochemical parameters in Monday Creek, Ohio, show that AMD eliminates fish communities and severely limits
macroinvertebrate communities in directly affected tributaries. Isolated headwaters in the heavily mined Monday Creek watershed
have relatively good water quality and habitat, but poor fish communities. Comparison of isolated Monday Creek headwaters
with non-isolated reaches in unmined watersheds indicates that differences in fish communities are attributable to isolation.
Fish communities in isolated headwaters have lower Indices of Biotic Integrity (IBI) than comparable non-isolated communities,
reduced species numbers, and lower numbers of individuals, despite suitable habitat as measured by the Qualitative Habitat
Evaluation Index (QHEI). Comparison of macroinvertebrate communities shows higher Invertebrate Community Indices (ICI), and
no apparent species loss, which can be attributed to the obligate flight stage in the life cycle of many macroinvertebrates,
which enables them to overcome aquatic barriers. The implication of this research is that there is an opportunity for recovery
of depleted fish communities in large AMD-isolated areas with good water quality, suitable habitat, and intact macroinvertebrate
communities, by downstream treatment or source control of AMD to create aquatic corridors for fish immigration. 相似文献
48.
Fish inhabiting fecally polluted bodies of water are often used for human consumption. Such fish can be contaminated by enteric human pathogens and may pose a potential risk to public health. Controlled experiments with 132 fish of 100 g average weight were conducted to evaluate the rate of contamination of various tissues of fish (tilapia hybrids). The fish were exposed to E. coli introduced into the ambient water at concentrations of up to 106 cfu/ml. Additional experiments were conducted with diluted wastewater containing Aeromonas, enterococci, fecal coliform and F+ coliphages. In another experiment poliovirus I was also added. The highest bacterial concentrations were recovered from the digestive tract (DT), some 5–24 h following exposure, with DT levels essentially similar to those in the inoculated water. In the E. coli experiments, geometric mean levels of about 102 cfu/cm2 were recovered from the skin, 26 cfu/g in the spleen and 102 cfu/g in the liver. Most of the muscle samples were not contaminated. Greater contamination was not found under conditions of stress such as high organic load, a water temperature of 37°C or low levels of dissolved oxygen. 相似文献
49.
新城中学是一所省级重点中学的迁建项目.通过介绍这一项目的立意和方案设计过程,为当前时代背景下创造中学校园特色空间提供思路与理念. 相似文献
50.
针对群体智能算法在结构优化设计领域中的应用,介绍了当前存在的一些群体智能算法,包括蚁群算法、鱼群算法和粒子群算法,阐述了其工作原理和特点,同时,对该算法在结构优化设计中的应用发展进行了展望。 相似文献