防风网对煤堆遮风效果的风洞实验研究

为了考察防风网对堆场煤堆的遮风效果,进行了防风网与煤堆之间区域的流场可视化实验。使用风洞模拟大气边界层条件,并将开孔率为38.5%的防风网模型布置在煤堆模型前方。实验中采用粒子成像测速(PIV)系统测量了防风网和堆场区域的平均风速分布,并且获得了煤堆表面的摩擦风速分布,进一步估算煤堆起尘量的变化情况。实验发现,防风网可有效降低煤堆表面迎风区域的摩擦风速,而对背风面的流场分布影响较小。研究结果可为防风网的遮护作用提供一定的实验支持。

Conditioned secretome of adipose-derived stem cells improves dextran sulfate sodium-induced colitis in mice

BACKGROUND Inflammatory bowel diseases(IBD)is related to uncontrolled immune response.Currently,there is no successful treatment for significant improvement in IBD.Stem cells display their therapeutic effects through their repopulating capacity or secreting factors.AIM To investigate the effects of conditioned mouse adipose-derived stem cells(mADSCs)secretome on colitis-induced mice.METHODS mADSCs were isolated from adipose tissue of C57BL/6 mice.Conditioned mADSCs secrectome was obtained by culturing of mADSCs with lipopolysaccharides(LPS,1μg/mL)for 24 h.Acute colitis was induced by 2%dextran sulfate sodium(DSS)drinking water for 7 d and then normal drinking water for 4 d.The mice were treated with normal culture medium(NM group),conditioned mADSCs secretome(CM group)or mADSCs(SC group).The length of colon and histopatholgy of colon tissues were evaluated.The mRNA expression levels of inflammatory cytokines in colon tissue and the serum interleukin(IL)-6 levels were determined.RESULTS The isolated mADSCs maintained the mADSCs specific gene expression profiles during experiment.The conditioned mADSCs secretome released by the treatment of mADSCs with LPS contained mainly inflammatory chemokines,colony-stimulating factors and inflammatory cytokines.The loss of body weight and reduction in colon length were ameliorated in the CM group.The conditioned mADSCs secretome reduced the histological score in colon tissue.The expression of IL-1b and IL-6 mRNAs in colon tissues significantly inhibited in the CM group compared to SC group and NM group,respectively.The elevation of serum IL-6 levels was also ameliorated in the CM group.These results indicate that the conditioned mADSCs secretome suppressed the synthesis of inflammatory cytokines in damaged colon tissue and the elevation of serum IL-6 concentration in DSS-induced mice CONCLUSION Conditioned mADSCs secretome might play regenerative roles by the suppression of IL-6 in serum and tissue during acute colitis,and may be more effective than stem cells themselves in the regeneration of colon tissue.

Deep Learning for Multivariate Prediction of Building Energy Performance of Residential Buildings

In the quest to minimize energy waste,the energy performance of buildings(EPB)has been a focus because building appliances,such as heating,ventilation,and air conditioning,consume the highest energy.Therefore,effective design and planning for estimating heating load(HL)and cooling load(CL)for energy saving have become paramount.In this vein,efforts have been made to predict the HL and CL using a univariate approach.However,this approach necessitates two models for learning HL and CL,requiring more computational time.Moreover,the one-dimensional(1D)convolutional neural network(CNN)has gained popularity due to its nominal computa-tional complexity,high performance,and low-cost hardware requirement.In this paper,we formulate the prediction as a multivariate regression problem in which the HL and CL are simultaneously predicted using the 1D CNN.Considering the building shape characteristics,one kernel size is adopted to create the receptive fields of the 1D CNN to extract the feature maps,a dense layer to interpret the maps,and an output layer with two neurons to predict the two real-valued responses,HL and CL.As the 1D data are not affected by excessive parameters,the pooling layer is not applied in this implementation.Besides,the use of pooling has been questioned by recent studies.The performance of the proposed model displays a comparative advantage over existing models in terms of the mean squared error(MSE).Thus,the proposed model is effective for EPB prediction because it reduces computational time and significantly lowers the MSE.

Prediction of NFT Sale Price Fluctuations on OpenSea Using Machine Learning Approaches

The rapid expansion of the non-fungible token(NFT)market has attracted many investors.However,studies on the NFT price fluctuations have been relatively limited.To date,the machine learning approach has not been used to demonstrate a specific error in NFT sale price fluctuation prediction.The aim of this study was to develop a prediction model for NFT price fluctuations using the NFT trading information obtained from OpenSea,the world’s largest NFT marketplace.We used Python programs to collect data and summarized them as:NFT information,collection information,and related account information.AdaBoost and Random Forest(RF)algorithms were employed to predict the sale price and price fluctuation of NFTs using regression and classification models,respectively.We found that the NFT related account information,especially the number of favorites and activity status of creators,confer a good predictive power to both the models.AdaBoost in the regression model had more accurate predictions,the root mean square error(RMSE)in predicting NFT sale price was 0.047.In predicting NFT sale price fluctuations,RF performed better,which the area under the curve(AUC)reached 0.956.We suggest that investors should pay more attention to the information of NFT creators.We anticipate that these prediction models will reduce the number of investment failures for the investors.

GRU-based Buzzer Ensemble for Abnormal Detection in Industrial Control Systems

Recently,Industrial Control Systems(ICSs)have been changing from a closed environment to an open environment because of the expansion of digital transformation,smart factories,and Industrial Internet of Things(IIoT).Since security accidents that occur in ICSs can cause national confusion and human casualties,research on detecting abnormalities by using normal operation data learning is being actively conducted.The single technique proposed by existing studies does not detect abnormalities well or provide satisfactory results.In this paper,we propose a GRU-based Buzzer Ensemble for AbnormalDetection(GBE-AD)model for detecting anomalies in industrial control systems to ensure rapid response and process availability.The newly proposed ensemble model of the buzzer method resolves False Negatives(FNs)by complementing the limited range that can be detected in a single model because of the internal models composing GBE-AD.Because the internal models remain suppressed for False Positives(FPs),GBE-AD provides better generalization.In addition,we generated mean prediction error data in GBE-AD and inferred abnormal processes using soft and hard clustering.We confirmed that the detection model’s Time-series Aware Precision(TaP)suppressed FPs at 97.67%.The final performance was 94.04%in an experiment using anHIL-basedAugmented ICS(HAI)Security Dataset(ver.21.03)among public datasets.

Delayed-onset endophthalmitis associated with Achromobacter species developed in acute form several months after cataract surgery:Three case reports

BACKGROUND Achromobacter species-associated endophthalmitis is rare and may present as either acute or chronic postoperative endophthalmitis.Delayed-onset Achromobacter species endophthalmitis appearing in acute presentation that develops more than several months after cataract surgery is very rare.Intraocular lens(IOL)removal is commonly recommended to treat Achromobacter species endophthalmitis,which is based on previous studies.Here,we report the results of surgery without IOL removal when treating patients with delayed-onset postoperative Achromobacter species endophthalmitis that developed in an acute form.CASE SUMMARY Three patients visited our ophthalmology clinic due to visual impairment that began 2-3 d earlier.They had undergone cataract surgery 5-18 mo prior.Bestcorrected visual acuity of the diseased eye was between counting fingers at 30 cm to non-light perception.They showed conjunctival injection,inflammation in the anterior chamber(cell reaction 4+)and hypopyon formation.The patients were diagnosed with infectious endophthalmitis and immediately underwent pars plana vitrectomy,anterior chamber irrigation and intravitreal injection of ceftazidime and vancomycin.Before fluid infusion,a vitreous specimen was obtained. In all cases, the IOLs were not removed. Achromobacter species was detected on vitreousspecimen culture. After surgery, the vitreous opacity decreased gradually and there was littleretinal damage. At 1 mo after treatment, the best-corrected visual acuity had improved to 20/50and 20/40.CONCLUSIONDelayed onset postoperative endophthalmitis caused by Achromobacter species can appear in anacute form. All patients responded well to early vitrectomy and administration of empiricalantibiotics including ceftazidime. There was no need for IOL removal during surgery.

View Types and Visual Communication Cues for Remote Collaboration

Over the last several years,remote collaboration has been getting more attention in the research community because of the COVID-19 pandemic.In previous studies,researchers have investigated the effect of adding visual communication cues or shared views in collaboration,but there has not been any previous study exploring the influence between them.In this paper,we investigate the influence of view types on the use of visual communication cues.We compared the use of the three visual cues(hand gesture,a pointer with hand gesture,and sketches with hand gesture)across two view types(dependent and independent views),respectively.We conducted a user study,and the results showed that hand gesture and sketches with the hand gesture cueswerewell matchedwith the dependent viewcondition,and using a pointer with the hand gesture cue was suited to the independent view condition.With the dependent view,the hand gesture and sketch cues required less mental effort for collaborative communication,had better usability,provided better message understanding,and increased feeling of co-presence compared to the independent view.Since the dependent view supported the same viewpoint between the remote expert and a local worker,the local worker could easily understand the remote expert’s hand gestures.In contrast,in the independent view case,when they had different viewpoints,it was not easy for the local worker to understand the remote expert’s hand gestures.The sketch cue had a benefit of showing the final position and orientation of the manipulating objects with the dependent view,but this benefit was less obvious in the independent view case(which provided a further view compared to the dependent view)because precise drawing in the sketches was difficult from a distance.On the contrary,a pointer with the hand gesture cue required less mental effort to collaborate,had better usability,provided better message understanding,and an increased feeling of co-presence in the independent view condition than in the dependent view condition.The pointer cue could be used instead of a hand gesture in the independent view condition because the pointer could still show precise pointing information regardless of the view type.