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Rhombic Cell Analysis - A New Way of Probing the Large- Scale Structure of the Universe. I.General Considerations
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作者 T.Kiang 《Chinese Journal of Astronomy and Astrophysics》 CSCD 北大核心 2003年第2期95-104,共10页
A new way of probing the large-scale structure of the universe is proposed. Space is partitioned into cells the shape of rhombic dodecahedron. The cells are labelled 'filled' or 'empty' according as th... A new way of probing the large-scale structure of the universe is proposed. Space is partitioned into cells the shape of rhombic dodecahedron. The cells are labelled 'filled' or 'empty' according as they contain galaxies or not. The cell size is so chosen as to have nearly equal numbers of filled and empty cells for the given galaxy sample. Two observables on each cell are definable: the number of its like neighbors, n1, and a two-suffixed topological type τ, the suffixes being the numbers of its like and unlike neighbor-groups. The frequency distributions of n1 and T in the observed set of filled (empty) cells are then considered as indicators of the morphology of the set. The method is applied to the CfA catalogue of galaxies as an illustration. Despite its limited size, the data offers evidence 1) that the empty cells are more strongly clustered than the filled cells, and 2) that the filled cells, but not the empty cells, have a tendency to occur in sheets. Further directions of development both in theory and application are indicated. 展开更多
关键词 cosmology: large-scale structure of universe - cosmology: observations - CfA Catalogue
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Time Definition Using the Extrinsic Universe: Expanding the Big Bang Theory
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作者 Yuri Nunes Silva 《Journal of High Energy Physics, Gravitation and Cosmology》 2025年第1期168-182,共15页
This paper aims to define the concept of time and justify its properties within the universal context, shedding new light on the nature of time. By employing the concept of the extrinsic universe, the paper explains t... This paper aims to define the concept of time and justify its properties within the universal context, shedding new light on the nature of time. By employing the concept of the extrinsic universe, the paper explains the observable universe as the three-dimensional surface of a four-dimensional 3-sphere (hypersphere), expanding at the speed of light. This expansion process gives rise to what we perceive as time and its associated aspects, providing a novel interpretation of time as a geometric property emerging from the dynamics of the universe’s expansion. The work offers insights into how this extrinsic perspective can address phenomena such as the universe’s accelerated expansion and dark matter, aligning the model with current observational data. 展开更多
关键词 Extrinsic universe Time: Origin and Nature Cosmology: universe Expansion Dark Energy and Dark Matter
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Erratum to “Data from Twenty-Three FRB’s Confirm the Universe Is Static and Not Expanding”, [Journal of High Energy Physics, Gravitation and Cosmology 2024, 10, 1152-1177]
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作者 Lyndon Errol Ashmore 《Journal of High Energy Physics, Gravitation and Cosmology》 2025年第1期165-167,共3页
Dispersion measure in an FRB’s signal is produced by the photons of the radio waves interacting with the free electrons in the IGM. In New Tired Light (NTL), redshifts are produced by the photons of light interacting... Dispersion measure in an FRB’s signal is produced by the photons of the radio waves interacting with the free electrons in the IGM. In New Tired Light (NTL), redshifts are produced by the photons of light interacting with these self-same electrons and so, one would expect a direct relationship between the DM of an FRB and the redshift of the host galaxy. However, workers in this field assume expansion and weight the DM by dividing it by the scale factor (1 + z) to allow for expansion. Once this weighting is removed, it was predicted back in 2016 (when the first FRB was localized) and later presented at a conference and published in the proceedings that, as more FRB’s were localized, a graph of DM versus ln(1 + z) would be a straight line of gradient (mec/2hre) or 7.32 × 1025 m−2 in SI units. The original paper had twenty-four data points but this has risen significantly to sixty-four useable FRB’s and so this corrigendum updates that paper so that all sixty-four are used. The data give a straight-line graph of gradient 7.12 × 1025 m−2, a difference of 3% from (mec/2hre) predicted nine years earlier. 展开更多
关键词 REDSHIFT Dispersion Measure Fast Radio Bursts FRB’s Tired Light Static universe IGM
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Thoughts Concerning the Origin of Our Fractal Universe
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作者 J. C. Botke 《Journal of Modern Physics》 2025年第1期167-197,共31页
During the past few decades, it has become clear that the distribution, sizes, and masses of cosmic structures are best described as fractal rather than homogeneous. This means that an entirely different formalism is ... During the past few decades, it has become clear that the distribution, sizes, and masses of cosmic structures are best described as fractal rather than homogeneous. This means that an entirely different formalism is needed to replace the standard perturbation model of structure formation. Recently, we have been developing a model of cosmology that accounts for a large number of the observed properties of the universe. A key component of this model is that fractal structures that later regulated the creation of both matter and radiation came into existence during the initial Planck-era inflation. Initially, the vacuum was the only existence and since time, distance, and energy were uncertain, its only property, the curvature (or energy), was most likely distributed randomly. Everything that happened after the Planck era can be described by the known laws of physics so the remaining fundamental problem is to discover how such a random beginning could organize itself into the hierarchy of highly non-random self-similar structures on all length scales that are necessary to explain the existence of all cosmic structures. In this paper, we present a variation of the standard sandpile model that points to a solution. Incidental to our review of the distributions of cosmic structures, we discovered that the apparent transition from a fractal to a homogeneous distribution of structures at a distance of about 150 Mpc is a consequence of the finite size of the universe rather than a change in the underlying statistics of the distributions. 展开更多
关键词 Early universe Fractal Distributions NUCLEOSYNTHESIS Cosmic Structures Time-Varying Curvature
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Listening to Echoes of Immemorial Big Bang——AliCPT Sets Out to Investigate Early-Time Universe
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作者 SONG Jianlan 《Bulletin of the Chinese Academy of Sciences》 2025年第4期213-216,共4页
In July,the Ali CMB Polariza〓〓tion Telescope(AliCPT)of〓〓ficially released high-quality maps of 150 GHz radiation from the Moon and Jupiter.The quality of these images not only validates the exceptional performance... In July,the Ali CMB Polariza〓〓tion Telescope(AliCPT)of〓〓ficially released high-quality maps of 150 GHz radiation from the Moon and Jupiter.The quality of these images not only validates the exceptional performance of the core instrument of AliCPT-1 but also signifies the successful completion of its first-stage con〓〓struction. 展开更多
关键词 moon JUPITER alicpt ali cmb polariza tion early time universe big bang cmb polarization high quality maps
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Messenger from the Early Universe-Einstein Probe Fuels New Hope for High-redshift GRB Observations
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作者 SONG Jianlan 《Bulletin of the Chinese Academy of Sciences》 2025年第1期51-54,共4页
A team of researchers from the Beijing Normal University,the Institute of High Energy Physics(IHEP)under the Chinese Academy of Sciences(CAS),and the National Astronomical Observatories,CAS(NAOC),reported in Nature As... A team of researchers from the Beijing Normal University,the Institute of High Energy Physics(IHEP)under the Chinese Academy of Sciences(CAS),and the National Astronomical Observatories,CAS(NAOC),reported in Nature Astronomy on January 23,2025 their discovery of an X-ray flash about 12.5 billion lightyears away.The signals burst out only 1.2 billion years after the Big Bang,when our 13.8-billion-year-old universe was still in its infancy,and a science satellite swiftly recorded them. 展开更多
关键词 science satellite big bangwhen early universe high energy physics ihep MESSENGER einstein probe high redshift grb big bang
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Primordial Black Holes Formed during Magneto-Hydrodynamic Turbulence in the Early Universe as Dominant Part of Dark Matter
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作者 Jia-Xiang Liang Peng Xu +1 位作者 Ming-Hui Du Zi-Ren Luo 《Chinese Physics Letters》 2025年第11期393-399,共7页
Primordial black holes(PBHs) offer a compelling candidate for dark matter. The production of PBHs through well-tested and accepted physical processes is highly worthy of investigation. This work highlights the role of... Primordial black holes(PBHs) offer a compelling candidate for dark matter. The production of PBHs through well-tested and accepted physical processes is highly worthy of investigation. This work highlights the role of turbulences in the very early universe in sustaining intense and persistent fluctuations in energy or mass density,which could provide a natural mechanism for PBH formation in the primordial universe. We analyze the mass range and abundance of PBHs produced in the magnetohydrodynamic turbulence induced by the electroweak phase transition. Remarkably, we find that the mass range of the produced PBHs falls within the most viable“asteroid mass” window from the present-day observations, and within natural parameter regions their abundance can be sufficiently large. These findings suggest that PBHs produced during magnetohydrodynamic turbulence in the very early universe may comprise a dominant part of dark matter. 展开更多
关键词 primordial universe primordial black holes pbhs electroweak phase transition primordial black holes mass range dark matter magnetohydrodynamic turbulence
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Studying Thermal and Dynamical Stability of Interacting Rényi and Tsallis Holographic Dark Energy Models in LTB Inhomogeneous Universe
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作者 Mohamed Abdelrashied Ayman Aly Mustafa Selim 《Research in Astronomy and Astrophysics》 2025年第2期110-123,共14页
This work aims to investigate the different stability conditions of two scenarios of the inhomogeneous Lemaitre–Tolman–Bond model of the universe with holographic dark energy.We considered the Rényi and Tsallis... This work aims to investigate the different stability conditions of two scenarios of the inhomogeneous Lemaitre–Tolman–Bond model of the universe with holographic dark energy.We considered the Rényi and Tsallis holographic models of interacting dark energy.These holographic models are investigated using the IR cutoff that equals the Hubble horizon.Various stability conditions of these models have been investigated to understand how much these models can tell us about the recent and future epochs of the universe in comparison with the cosmological constant model,orΛCDM model.The conditions of violating the cosmological energy conditions have been studied.The evolution of the entropy and its first and second derivatives have been calculated and plotted for these holographic models.This gives an idea of how far these models satisfy the generalized second law of thermodynamics and hence have thermodynamical stability.The dynamical stability is studied for these evolved models,which give us glimpses of the dynamical stability at different phases of its evolution.We focus on investigating the stability in recent and near future times up to z≤-4.Further investigation of stability has been obtained by studying the evolved sound speed squared parameter for these models,which gave us a final and decisive evaluation of the stability of these models. 展开更多
关键词 (cosmology:)cosmological parameters (cosmology:)dark energy (cosmology:)large-scale structure of universe cosmology:theory
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Variable universe fuzzy expert system for aluminum electrolysis 被引量:3
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作者 曹丹阳 曾水平 李晋宏 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第2期429-436,共8页
In aluminum electrolytic process, the variables affect the current efficiency and the stability of electrolysis cells. AIF3 addition and aluminum tapping volume are two important factors that affect economic benefits ... In aluminum electrolytic process, the variables affect the current efficiency and the stability of electrolysis cells. AIF3 addition and aluminum tapping volume are two important factors that affect economic benefits of aluminum electrolytic production. Fuzzy logic provides a suitable mechanism to describe the relationship between the process variables and the current efficiency. Fuzzy expert system based on Mamdani fuzzy inference process for aluminum electrolysis was adopted to adjust A1F3 addition and aluminum tapping volume. A novel variable universe approach was applied in the system to solve the problem that different electrolysis cells have different universes of variables. The system was applied to 300 kA aluminum electrolysis cells in a aluminum plant. Experimental results showed that the electrolyte temperature was kept stably between 945 and 955℃, the current efficiency reached 93.5%, and the DC power consumption was 13 000 kW.h per ton aluminum. 展开更多
关键词 variable universe fuzzy expert system aluminum electrolysis
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Universe分解中纽结的孤立性
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作者 陶志雄 《浙江科技学院学报》 CAS 2009年第4期313-315,共3页
给出了孤立纽结分解的定义,所谓孤立的(非平凡)纽结分解,即在不改变投影的前提下,universe分解中的该纽结改变其任何一个交叉都是平凡纽结。通过分析和讨论各种可能情形,回答了二重点为n(≤5)的素universe分解中是否存在孤立的交叉数为... 给出了孤立纽结分解的定义,所谓孤立的(非平凡)纽结分解,即在不改变投影的前提下,universe分解中的该纽结改变其任何一个交叉都是平凡纽结。通过分析和讨论各种可能情形,回答了二重点为n(≤5)的素universe分解中是否存在孤立的交叉数为n的非平凡纽结分解的问题。 展开更多
关键词 universe 纽结 分解 孤立的纽结分解
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Classical Instability of Anti-de Sitter Universe
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作者 XU Jianmei LI Lixin LIU Liao 《Chinese Physics Letters》 SCIE CAS CSCD 1994年第3期189-192,共4页
This article discusses the gravitational stability of anti-de Sitter universe.It turns out that anti-de Sitter universe with closed timelike curves is unstable to gravitational perturbations.
关键词 GRAVITATIONAL universe. universe
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IMAGE SPLITTINGS IN AN INHOMOGENEOUS UNIVERSE
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作者 WU Xiangping 《Chinese Physics Letters》 SCIE CAS CSCD 1990年第1期44-47,共4页
In the previous paper(Chin.Phys.lett.6(1989)233)the-amplification,luminosity distances and probabilities for lensing an the case of small optical depth were discussed.As the second part of this work,the present paper ... In the previous paper(Chin.Phys.lett.6(1989)233)the-amplification,luminosity distances and probabilities for lensing an the case of small optical depth were discussed.As the second part of this work,the present paper will deal with multiple images produced by pointlike lensing objects which are assumed to be the dominant contributors of inhomogeneities in the universe.The expectation values of image separations,the visual magnitude and solid angle of each image will be calculated. 展开更多
关键词 universe. MAGNITUDE IMAGES
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Standards help shape the future responsibly
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作者 Erik Vladimir Simic 《China Standardization》 2026年第1期50-51,共2页
I come from Slovenia,a small but ambitious country from Central Europe.I study at the Faculty of Electrical Engineering at the University of Ljublgana.I have the privilege of being one of the first young ambassadors o... I come from Slovenia,a small but ambitious country from Central Europe.I study at the Faculty of Electrical Engineering at the University of Ljublgana.I have the privilege of being one of the first young ambassadors of standardization not only in Slovenia but of this generation across the entire world. 展开更多
关键词 STANDARDS UNIVERSITY RESPONSIBILITY electrical engineering young ambassadors future slovenia central europe
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Prevalence and sociodemographic predictors of bullying among university students in Jordan:a cross-sectional study
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作者 Majd Alebeah Mohammad Suliman +5 位作者 Asem Abdalrahim Abdullah Alkhawaldeh MeanAljezawi Mohammed ALBashtawy Jamal Qaddumi Wesam Taher Almagharbeh 《Frontiers of Nursing》 2026年第1期139-146,共8页
Objective:To determine the prevalence of bullying among university students in Jordan.The study also aims to identify potential predictors of bullying within the context of university students in Jordan.Methods:A cros... Objective:To determine the prevalence of bullying among university students in Jordan.The study also aims to identify potential predictors of bullying within the context of university students in Jordan.Methods:A cross-sectional study using a convenience sampling method was conducted with 350 university students from 3 institutions(2 public and 1 private),who par ticipated in this study.Data were collected through a self-repor ted questionnaire.Data analysis employed descriptive statistics,and multivariate linear regression was executed through the SPSS program(version 26)(IBM Corporation,Armonk,New York,United States)at 5% level of significance.Results:The findings revealed that 30% of the surveyed students reported never experiencing bullying,41.1% indicated rare exposure,20% reported occasional bullying,4.3% noted frequent exposure,and 4.6% reported constant exposure.Statistical analysis identified university and academic year as significant predictors of bullying.The university exhibited significance(B=-0.403,P≤0.05),while the academic year was also a significant predictor(B=0.213,P≤0.05).Conclusions:Given the prevalence and predictors identified,this study recommends the implementation of policies in universities to safeguard students from bullying.These policies should specifically target the most affected individuals. 展开更多
关键词 BULLYING bullying prevalence JORDAN sociodemographic predictors university students
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LUAR:Lightweight and Universal Attribute Revocation Mechanism with SGX Assistance towards Applicable ABE Systems
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作者 Fei Tang Ping Wang +3 位作者 Jiang Yu Huihui Zhu Mengxue Qin Ling Yang 《Computers, Materials & Continua》 2026年第3期1628-1646,共19页
Attribute-Based Encryption(ABE)has emerged as a fundamental access control mechanism in data sharing,enabling data owners to define flexible access policies.A critical aspect of ABE is key revocation,which plays a piv... Attribute-Based Encryption(ABE)has emerged as a fundamental access control mechanism in data sharing,enabling data owners to define flexible access policies.A critical aspect of ABE is key revocation,which plays a pivotal role in maintaining security.However,existing key revocation mechanisms face two major challenges:(1)High overhead due to ciphertext and key updates,primarily stemming from the reliance on revocation lists during attribute revocation,which increases computation and communication costs.(2)Limited universality,as many attribute revocation mechanisms are tailored to specific ABE constructions,restricting their broader applicability.To address these challenges,we propose LUAR(Lightweight and Universal Attribute Revocation),a novel revocation mechanism that leverages Intel Software Guard Extensions(SGX)while minimizing its inherent limitations.Given SGX’s constrained memory(≈90 MB in a personal computer)and susceptibility to side-channel attacks,we carefully manage its usage to reduce reliance while mitigating potential collusion risks between cloud service providers and users.To evaluate LUAR’s lightweight and universality,we integrate it with the classic BSW07 scheme,which can be seamlessly replaced with other ABE constructions.Experimental results demonstrate that LUAR enables secure attribute revocation with low computation and communication overhead.The processing time within the SGX environment remains stable at approximately 55 ms,regardless of the complexity of access policies,ensuring no additional storage or computational burden on SGX.Compared to the Hardware-based Revocable Attribute-Based Encryption(HR-ABE)scheme(IEEE S&P 2024),LUAR incurs a slightly higher computational cost within SGX;however,the overall time from initiating a data request to obtaining plaintext is shorter.As access policies grow more complex,LUAR’s advantages become increasingly evident,showcasing its superior efficiency and broader applicability. 展开更多
关键词 Attribute-based encryption attribute revocation LIGHTWEIGHT UNIVERSALITY
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Bridging youth passion with global standards
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《China Standardization》 2026年第1期2-3,共2页
To help university students know more about standards,and attract them to par ticipate in s tandardization ac tivities,the International Standardization Youth Star Competition was initiated by the International Standa... To help university students know more about standards,and attract them to par ticipate in s tandardization ac tivities,the International Standardization Youth Star Competition was initiated by the International Standardization Outstanding Contribution Award Foundation(ISOCAF)in 2023,and has been held since then for three consecutive years in China.The 2025 Competition attracted 236 teams nationwide who demonstrated great enthusiasm for engaging in the standardization undertaking.The SPECIAL REPORT column presents the series reports on the competition,which is expected to inspire more young minds to step forward,innovate with purpose,and shape a future where standards unite ambition with impact. 展开更多
关键词 COMPETITION global standards YOUTH standardization innovation youth star competition university students
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AFI:Blackbox Backdoor Detection Method Based on Adaptive Feature Injection
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作者 Simin Tang Zhiyong Zhang +3 位作者 Junyan Pan Gaoyuan Quan Weiguo Wang Junchang Jing 《Computers, Materials & Continua》 2026年第4期1890-1908,共19页
At inference time,deep neural networks are susceptible to backdoor attacks,which can produce attackercontrolled outputs when inputs contain carefully crafted triggers.Existing defense methods often focus on specific a... At inference time,deep neural networks are susceptible to backdoor attacks,which can produce attackercontrolled outputs when inputs contain carefully crafted triggers.Existing defense methods often focus on specific attack types or incur high costs,such as data cleaning or model fine-tuning.In contrast,we argue that it is possible to achieve effective and generalizable defense without removing triggers or incurring high model-cleaning costs.Fromthe attacker’s perspective and based on characteristics of vulnerable neuron activation anomalies,we propose an Adaptive Feature Injection(AFI)method for black-box backdoor detection.AFI employs a pre-trained image encoder to extract multi-level deep features and constructs a dynamic weight fusionmechanism for precise identification and interception of poisoned samples.Specifically,we select the control samples with the largest feature differences fromthe clean dataset via feature-space analysis,and generate blended sample pairs with the test sample using dynamic linear interpolation.The detection statistic is computed by measuring the divergence G(x)in model output responses.We systematically evaluate the effectiveness of AFI against representative backdoor attacks,including BadNets,Blend,WaNet,and IAB,on three benchmark datasets:MNIST,CIFAR-10,and ImageNet.Experimental results show that AFI can effectively detect poisoned samples,achieving average detection rates of 95.20%,94.15%,and 86.49%on these datasets,respectively.Compared with existing methods,AFI demonstrates strong cross-domain generalization ability and robustness to unknown attacks. 展开更多
关键词 Deep learning backdoor attacks universal detection feature fusion backward reasoning
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Rethinking China's International Journalism Education:Lessons from Southeast Asia
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作者 Li Ying 《China Report ASEAN》 2026年第1期58-61,共4页
"Happy birthday to you,happy birthday,dearteacher!"On a bright,sunny mid-summer afternoon,the tune of the birthday song reverberated through a plain-looking classroom in University Padjadjaran's Faculty ... "Happy birthday to you,happy birthday,dearteacher!"On a bright,sunny mid-summer afternoon,the tune of the birthday song reverberated through a plain-looking classroom in University Padjadjaran's Faculty of Communication Sciences in Bandung,Indonesia.The opening session of the communication theory course coincided with one of the instructors'50th birthday.Athe end of the class,the students burst into singing,wishing their teacher a splendid start to her next decade. 展开更多
关键词 BIRTHDAY Southeast Asia communication theory international journalism education China UNIVERSITY communication sciences birthday song
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Messages from CEISEE 2025 Chairs
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作者 Xiaofei Xu Bing Wu +8 位作者 Chunming Hu Yves Ducq Xiangqian Wu Li Zhang Stephan Reiff-Marganiec Lanshun Nie Huobin Tan Weiwei Xing Weihua Guo 《计算机教育》 2026年第3期37-37,共1页
Welcome to the 21st China-Europe International Symposium on Software Engineering Education in 2025(CEISEE 2025),successfully held on September 20-21,2025,in Hangzhou,China.With the rapid development of generative AI a... Welcome to the 21st China-Europe International Symposium on Software Engineering Education in 2025(CEISEE 2025),successfully held on September 20-21,2025,in Hangzhou,China.With the rapid development of generative AI and the digital economy,software engineering education is entering a new era.CEISEE continues to be an important platform for educational institutions,the software industry,and educational authorities from China and Europe to exchange visions,share experience,and discuss innovative approaches to software engineering education and university-industry cooperation. 展开更多
关键词 university industry cooperation generative ai software industryand software engineering education software engineering digital economy
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Goal-Setting in the Information-Generating Environment of the Universe
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作者 Igor Bazhin 《Journal of Environmental Science and Engineering(B)》 2013年第9期538-544,共7页
Problem of goal-setting is related to the fundamental principles of informationology and general, rather than specific, aproaches, which enable a more adequate appraisal of certain managerial decisions in terms of the... Problem of goal-setting is related to the fundamental principles of informationology and general, rather than specific, aproaches, which enable a more adequate appraisal of certain managerial decisions in terms of their efficiency. In article this problem is considered and from positions of informationology is formulated and on the basis of a method of full mathematical induction the Law of positive dynamics of the Universe is proved. This law establishes preference of the positive purposes in all processes happening in the Universe. Thus, the goal-setting which is carried out from positions of the described Law is the important world outlook prerequisite searching, identification and development of strategic alternatives of purposeful social innovations. 展开更多
关键词 GOAL-SETTING informationology law of positive dynamics of the universe.
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