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A credible traffic prediction method based on self-supervised causal discovery

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Science China(Information Sciences) 2024年第5期67卷 244-258页

作者： Dan WANG Yingjie LIU Bin SONG State Key Laboratory of Integrated services Networks Xidian University

Next-generation wireless network aims to support low-latency, high-speed data transmission services by incorporating artificial intelligence(AI) technologies. To fulfill this promise, AI-based network traffic prediction is essential for pre-allocating resources, such as bandwidth and computing power. This can help reduce network congestion and improve the quality of service(QoS) for users. Most studies achieve future traffic prediction by exploiting deep learning and reinforcement learning, to mine spatio-temporal correlated variables. Nevertheless, the prediction results obtained only by the spatio-temporal correlated variables cannot reflect real traffic changes. This phenomenon prevents the true prediction variables from being inferred, making the prediction algorithm perform poorly. Inspired by causal science, we propose a novel network traffic prediction method based on self-supervised spatio-temporal causal discovery(SSTCD). We first introduce the Granger causal discovery algorithm to build a causal graph among prediction variables and obtain spatio-temporal causality in the observed data, which reflects the real reasons affecting traffic ***, a graph neural network(GNN) is adopted to incorporate causality for traffic prediction. Furthermore,we propose a self-supervised method to implement causal discovery to to address the challenge of lacking ground-truth causal graphs in the observed data. Experimental results demonstrate the effectiveness of the SSTCD method.

关键词： wireless network traffic prediction causal discovery self-supervised

Mitigate noisy data for smart IoT via GAN based machine unlearning

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Science China(Information Sciences) 2024年第3期67卷 62-78页

作者： Zhuo MA Yilong YANG Yang LIU Xinjing LIU Jianfeng MA School of Cyber Engineering Xidian University State Key Laboratory of Integrated services Networks (ISN)

With the development of IoT applications, machine learning dramatically improves the utility of variable IoT systems such as autonomous driving. Although the pretrain-finetune framework can cope well with data heterogeneity in complex IoT scenarios, the data collected by sensors often contain unexpected noisy data, e.g., out-of-distribution(OOD) data, which leads to the reduced performance of fine-tuned models. To resolve the problem, this paper proposes Mu GAN, a method that can mitigate the side-effect of OOD data via the generative adversarial network(GAN)-based machine unlearning. Mu GAN follows a straightforward but effective idea to mitigate the performance loss caused by OOD data, i.e., “flashbacking” the model to the condition where OOD data are excluded from model training. To achieve the goal, we design an adversarial game, where a discriminator is trained to identify whether a sample belongs to the training set by observing the confidence score. Meanwhile, a generator(i.e., the target model) is updated to fool the discriminator into believing that the OOD data are not included in the training set but others do. The experimental results show that benefiting from the high unlearning rate(more than 90%) and retention rate(99%), Mu GAN succeeds in lowering the model performance degradation caused by OOD data from 5.88% to 0.8%.

关键词： machine unlearning generative adversarial network out of distribution data Internet of Thing neural network

Experimental study on the CO_(2) concentration and age of air distribution inside tiny sleeping spaces

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Building Simulation 2024年第4期17卷 591-605页

作者： Jingying Zhang Yanyan Li Haiguo Yin Linfeng Liang Songmei Zu Le Gao Ying Zhang Angui Li School of Building services Science and Engineering Xi’an University of Architecture and TechnologyXi’anShaanxi710055China

In recent years,rapid urban development has led to capsule hotels,sleep pods,and other tiny sleeping spaces that adapt to people’s fast-paced lives,achieving maximum functionality with a very small ***,due to the small space,human metabolic pollutant(such as CO_(2))is more likely to accumulate,and the air is not easily *** this paper,a full-size experimental platform is set up with three types of ventilation modes to explore the exclusion efficiency of metabolic pollutants and the overall distribution of age of air under these ventilation *** conclusions showed that the mean values of metabolic pollutant exclusion rates for the different ventilation modalities varied very little across the spatial dimensions of the confined space but varied considerably in the area around the *** double-side attached ventilation method was the most effective in removing human metabolic pollutants,especially in the head region(CN≥0.92),while the single-wall attached ventilation method had the best air exchange efficiency(η≥0.85).This suggests an inconsistent distribution of CO_(2) and age of air,which is contrary to general common *** conclusions of this paper can guide the design of ventilation for tiny sleeping spaces.

关键词： attached ventilation mode human metabolic pollutant indoor air quality air exchange efficiency tiny sleeping spaces

High-frequency lacustrine sequence stratigraphy of clastic lakes: lessons from ancient successions

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Journal of Palaeogeography 2024年第4期13卷 621-645页

作者： Carlos Zavala Hua-Qing Liu Xiang-Bo Li Valentin Trobbiani Yang Li Mariano Arcuri Agustin Zorzano Departamento de Geología Universidad Nacional del Sur (UNS) GCS Consulting services.Bahía Blanca Research Institute of Petroleum Exploration&development-Northwest Consejo Nacional de Investigaciones Científicas y T ecnicas (CONICET) Shandong University of Science and Technology

Sequence stratigraphic concepts and methods provide novel tools for performing stratigraphic analysis, allowing us to improve our understanding of depositional models and basin evolution. Main controls and depositional elements(e.g., surfaces, systems tracts, parasequences, etc.) recognized in conventional sequence stratigraphy are designed for marine-related systems. In contrast, the sequence stratigraphy of lacustrine successions is much more complex and poorly understood, because it is not driven by sea-level changes, but by a complex interaction between tectonics and high-frequency climatic cycles. The comprehensive analysis of the water balance of lacustrine systems allows the recognition of three types of lake conditions: Underfilled, balanced-fill and overfilled lakes. Understanding the lake conditions in ancient successions is fundamental for unraveling lacustrine sequence stratigraphy, since these conditions effectively control water salinity, internal stacking pattern and the characteristics of systems tracts. Underfilled lakes are hydrologically closed lakes, and consequently, the lake-level can highly fluctuate, driven by high-frequency wet-dry climatic cycles. During wet periods, rivers supply water and sediments, resulting in fining-and thinning-upward elementary depositional sequences(EDS's) accumulated during the transgressive systems tract(TST). In contrast, dry periods are characterized by a relative lake-level fall with the subaerial exposure of lake margin areas during the regressive systems tract(RST). Lake water salinity can fluctuate from brackish to hypersaline. Balanced-fill lakes are partially closed lakes, and consequently, they have characteristics of both underfilled and overfilled lakes. During the TST, the lake is in underfilled condition, and consequently, the introduction of water and sediment will accumulate a fining-upward interval until reaching the spill point during the maximum flooding. The RST is accumulated under an overfille

关键词： Lacustrine sequence stratigraphy Underfilled lakes Balanced-fill lakes Overfilled lakes Forced transgression Forced regression

Enhancing heavy gas capture in confined spaces through ventilation control technology

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Building Simulation 2024年第7期17卷 1161-1182页

作者： Tianqi Wang Angui Li Yuanqing Ma Ying Zhang Haiguo Yin School of Building services Science and Engineering Xi’an University of Architecture and TechnologyNo.13 Yanta RDXi’anShaanxi710055China

Gas leakage accidents occur frequently in confined spaces,and heavy gases with a relative density greater than 1.15 among hazardous gases and greenhouse gases are commonly stored in confined ***,atmospheric pollutant emission standards are becoming more stringent,and it is essential to remove heavy gas after accidents while reducing emissions to the *** study proposes using a heavy gas collection tank(HGCT)to safeguard the internal environment and minimize emissions to the *** capture efficiencies applicable to heavy-gas environments under different ventilation strategies are *** research analyzes the impact of the exhaust rate,leakage rate,density of heavy gas,and air supply modes on the indoor concentration *** results demonstrate that the mass flow rate of heavy gas into the exhaust is positively correlated with the exhaust rate,but the gas from the exhaust system contains more *** exhaust rate should be greater than four times the space volume per hour;otherwise,heavy gas above 1000 ppm accumulates to a height of 0.67 m at ground ***,attachment ventilation as make-up air helps to reduce upstream heavy gas accumulation and reduces the extension of heavy gas along the room *** an HGCT with floor slope and attachment ventilation achieves an efficiency of 96.28%.This study provides valuable insights and references for preventing hazardous heavy gas leakage.

关键词： confined gases otherwise

Pregnancy stressors and postpartum symptoms of depression and anxiety:the moderating role of a cognitivebehavioural therapy(CBT)intervention

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General Psychiatry 2024年第1期37卷 112-121页

作者： Yunxiang Sun Soim Park Abid Malik Najia Atif Ahmed Zaidi Atif Rahman Pamela J Surkan Department of International Health Johns Hopkins University Bloomberg School of Public HealthBaltimoreMarylandUSA Department of Public Mental Health Health Services AcademyIslamabadPakistan Human development Research Foundation RawalpindiPakistan Department of Primary Care and Mental Health Institute of Population HealthUniversity of LiverpoolLiverpoolUK

Background Little is known about the association between stressors(especially positive stressors)during pregnancy and postpartum depression and *** We investigated the association between positive and negative stress events during different stages of pregnancy and postpartum mental health outcomes among low-income pregnant women with symptoms of anxiety in Pakistan and evaluated whether an intervention based on cognitive behavioural therapy(CBT)had a regulatory *** Participants were 621 pregnant Pakistani women with mild *** the Pregnancy Experience Scale-Brief Version,six scores were created to assess positive and negative *** performed a multivariate linear regression to examine whether these six scores,measured both at baseline and in the third trimester,were associated with postpartum anxiety and depressive *** effect of the intervention on this relationship was examined by adding an interaction term to the regression *** Hassles frequency measured in the third trimester was positively associated with depression(B=0.22,95%confidence interval(Cl):0.09 to 0.36)and anxiety(B=0.19,95%Cl:0.08to 0.30).At the same timepoint,uplifts intensity was negatively associated with symptoms of depression(B=-0.82,95%Cl:1.46 to-0.18)and anxiety(B=-0.70,95%Cl:-1.25 to-0.15),whereas hassles intensity was positively related to symptoms of depression(B=1.02,95%Cl:0.36 to 1.67)and anxiety(B=0.90,95%Cl:0.34 to 1.47).The intensity ratio of hassles to uplifts reported in the third trimester was positively related to both depression(B=1.40,95%Cl:0.59 to 2.20)and anxiety(B=1.26,95%Cl:0.57 to 1.96).The intervention strengthened the overall positive effects of uplfts and the negative effects of *** experiences at baseline during early pregnancy to mid-pregnancy were not associated with mental health *** Stressors in the third trimester but not earlier in pregnancy were associated with postpartum symptoms

关键词： postpartum stress behaviour

Assessment of the piroxicam-incited model of synchronized colitis in T-cell receptor alpha chain-deficient mice

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Animal Models and Experimental Medicine 2024年第4期7卷 533-543页

作者： Maximo E.Lange Danisa M.Bescucci Valerie F.Boras Tony Montina G.Douglas Inglis douglas inglis 11 lethbridge research and development centre agriculture and agri-food canadalethbridgealbertacanada alberta health services chinook regional hospitallethbridgealbertacanada department of chemistry and biochemistry university of lethbridgelethbridgealbertacanada southern alberta genome sciences centre university of lethbridgelethbridgealbertacanada

Background:A multitude of mouse models are utilized to emulate and study intestinal inflammation.T-cell receptor alpha chain(TCRα)-deficient mice are used as a model of spontaneous colitis that has similarities with human ulcerative ***,colitis is triggered late in the life of the mouse(age:4-5 months),and inflammation does not develop at the same time in different mice.A previously conducted study reported that the administration of the drug piroxicam triggered predictable and early colitis in TCRα-deficient mice at the age of 6-8 ***,a detailed characterization of ensuing inflammation was not ***:We conducted an in-depth examination of piroxicam-triggered colitis in TCRα-deficient mice,with emphasis on spatial histopathologic changes and analysis of expression of inflammatory ***,we tested amelioration of colitis with ***:We confirmed that piroxicam induced a time-prescribed colitis and did so in the proximal colon as well as the cecum of TCRα-deficient *** adminis-tration was observed to induce epithelial hyperplasia,goblet cell loss,and leukocyte infiltration with occasional ulceration.A Swiss roll technique was used to examine the colon and cecum in its ***,we observed that inflammation was mul-tifocal segmental,with areas of tissue damage in between healthy *** addition,we observed variability in the severity of inflammation among replicate animals and treatments,and that the administration of dexamethasone only partially ameliorated inflammation in the proximal ***:Piroxicam consistently induced multifocal segmental colitis in the proxi-mal colon and cecum,although the degree of inflammation was reduced in the ***,spatial variability in inflammation in the large intestine and the inter-replicate variation in the severity of inflammation must be taken into consideration when utilizing this murine model of synchronized colitis.

关键词： colon dexamethasone histology induction inflammation knockout

Protective and Regenerative Efficacy of a Plant Oil-Based Day and Night Cream: Investigated by a Novel Approach to Reveal the Impact of Blue Light Irradiation on Epidermal Barrier Integrity and Lipid Matrix

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Journal of Cosmetics, Dermatological Sciences and Applications 2024年第3期14卷 227-241页

作者： Dorothee Dähnhardt Stephan Dähnhardt-Pfeiffer Isabel Simon Dana Ditgen Inge Holland Dörte Segger Peter Staib Microscopy services Dhnhardt GmbH Flintbek Germany Research & development and Regulatory Affairs Kneipp GmbH Wuerzburg Germany SGS INSTITUT FRESENIUS GmbH Hamburg Germany

In recent years, the harmful effects of blue light (400 - 500 nm) as a component of visible light (400 - 700 nm) have increasingly gained attention of science, industry, and consumers. To date, only a few in vivo test methods for measuring the effects of blue light on the skin have been described. A direct measurement method that can detect the immediate effects of blue light on the epidermal permeability barrier (EPB) is still lacking. In this study, we present a new methodological approach that can be used to investigate both the protective and regenerative effects of cosmetic products on the EPB after blue light irradiation. In a study with 14 female volunteers, it was investigated whether the regular application of an O/W emulsion (day cream) can strengthen and protect the epidermal barrier against damaging blue light radiation of 60 J/cm2 (protective study design) and also whether a disruption of the epidermal barrier caused by blue light radiation is restored faster and better by the regular application of another O/W emulsion (night cream) than in product-untreated skin (regenerative study design). The two O/W emulsions are different in plant oil, active ingredient composition and texture. The seven-day treatment with the day cream initially led to a significant increase in the normalized lipid lamellae length in the intercellular space, whereas the irradiation with blue light after 24 hours led to a significant decrease in the lipid lamellae length in the untreated test area, but not in the area previously treated with the product. Regarding the regenerative study design, a two-day treatment with the night cream was able to restore a blue-light-induced decrease in lipid lamellae length in the intercellular space. In summary, with the study designs presented here, the protective and regenerative effect of two cosmetic products could be demonstrated for the first time on the integrity of the EPB after blue light irradiation and the data showed that the Lipbarv

关键词： Skin Care Blue Light Irradiation Skin Barrier Intercellular Lipid Lamellae Electron Microscopy

Resource Allocation in Multi-User Cellular Networks:A Transformer-Based Deep Reinforcement Learning Approach

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China Communications 2024年第5期21卷 77-96页

作者： Zhao Di Zheng Zhong Qin Pengfei Qin Hao Song Bin State Key Laboratory of Integrated services Networks Xidian University710071China China Academy of Space Technology Beijing 100081China

To meet the communication services with diverse requirements,dynamic resource allocation has shown increasing *** this paper,we consider the multi-slot and multi-user resource allocation(MSMU-RA)in a downlink cellular scenario with the aim of maximizing system spectral efficiency while guaranteeing user *** first model the MSMURA problem as a dual-sequence decision-making process,and then solve it by a novel Transformerbased deep reinforcement learning(TDRL)***,the proposed TDRL approach can be achieved based on two aspects:1)To adapt to the dynamic wireless environment,the proximal policy optimization(PPO)algorithm is used to optimize the multi-slot RA strategy.2)To avoid co-channel interference,the Transformer-based PPO algorithm is presented to obtain the optimal multi-user RA scheme by exploring the mapping between user sequence and resource *** results show that:i)the proposed approach outperforms both the traditional and DRL methods in spectral efficiency and user fairness,ii)the proposed algorithm is superior to DRL approaches in terms of convergence speed and generalization performance.

关键词： dynamic resource allocation multi-user cellular network spectrum efficiency user fairness

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