Digital Twins for Engineering Asset Management:Synthesis,Analytical Framework,and Future Directions

Effective engineering asset management(EAM)is critical to economic development and improving livability in society,but its complexity often impedes optimal asset functionalities.Digital twins(DTs)could revolutionize the EAM paradigm by bidirectionally linking the physical and digital worlds in real time.There is great industrial and academic interest in DTs for EAM.However,previous review studies have predominately focused on technical aspects using limited life-cycle perspectives,failing to holistically synthesize DTs for EAM from the managerial point of view.Based on a systematic literature review,we introduce an analytical framework for describing DTs for EAM,which encompasses three levels:DT 1.0 for technical EAM,DT 2.0 for technical-human EAM,and DT 3.0 for technical-environmental EAM.Using this framework,we identify what is known,what is unknown,and future directions at each level.DT 1.0 addresses issues of asset quality,progress,and cost management,generating technical value.It lacks multi-objective self-adaptive EAM,however,and suffers from high application cost.It is imperative to enable closed-loop EAM in order to provide various functional services with affordable DT 1.0.DT 2.0 accommodates issues of human-machine symbiosis,safety,and flexibility management,generating managerial value beyond the technical performance improvement of engineering assets.However,DT 2.0 currently lacks the automation and security of human-machine interactions and the managerial value related to humans is not prominent enough.Future research needs to align technical and managerial value with highly automated and secure DT 2.0.DT 3.0 covers issues of participatory governance,organization management,sustainable development,and resilience enhancement,generating macro social value.Yet it suffers from organizational fragmentation and can only address limited social governance issues.Numerous research opportunities exist to coordinate different stakeholders.Similarly,future research opportunities exist to develop DT 3.0 in a more open and complex system.

用LOL-π分析展示B_(3)N_(3)六元环的离域π电子和芳香性——推荐一个普适性的计算化学实验

B_(3)N_(3)独特的六元环结构是研究非苯芳香性的理想模板。本实验在B3LYP-D3(BJ)/def2-TZVP水平上优化了B_(3)N_(3)六元环结构并进行频率验证,用Multiwfn3.7(dev)绘制了其LOL-π填色图,完美展示了六元环的离域π电子分布和非苯芳香性特征。实验普适性和可操作性强,安全性高,易于推广。

中国首批APEC低碳示范城镇发展状况的数据分析研究

面对全球气候变化,中国政府在2014中国年APEC领导人峰会之际,提出了APEC低碳示范城镇推广活动,加强与国际合作交流.通过整理首批入库城镇资料,依次对本次参评城镇的区域分布基本特征,技术路径、规划成果和国际合作程度,以及低碳城镇的评价办法等三个方面的数据资料,进行了全面的统计分析,得出了中国首次APEC低碳示范城镇推广活动的成功和不足之处.同时,对APEC低碳示范城镇推广活动提出一些可行性的建议,为以后国内外低碳城镇发展提供参考意见.

综合能源站内土壤源热泵运行效果研究

为了确定综合能源站内土壤源热泵的运行效果及调节措施，本文通过对天津某综合能源站内土壤源热泵用户侧供能量、地源侧换热量、地埋管供水温度进行连续三年的监测，分析机组直接供能和蓄能运行工况下的平均运行效率。研究结果表明，能源站集中供能可很好地调配各设备的供能量。三年来，土壤源热泵机组白天供能、晚上蓄能，平均运行效率为机组额定COP值的91．4％～112．7％，不仅保证各机组均能以高效率运行，且可节约运行费用，减少碳排放。研究成果可为土壤源热泵系统在能源站中的运行提供参考。

Role of intestinal flora imbalance in pathogenesis of pouchitis

Objective: To discuss the role of intestinal flora imbalance in the pathogenesis of pouchitis. Methods: The puochitis rat model was established and the faeces sample and the mucous membrane sample were collected regularly, in which the bacterial nucleic acids were extracted for quantitative analysis of the intestinal flora in the samples through using the real-time quantitative PCR technique and high energy sequencing technology. Results: The disorder phenomenon of the intestinal flora appeared at the 7th day of the experiment, and the pouchitis was presented at the 21 th day of the experiment. At the 31 th day of the experiment, compared to control group and non-pouchitis group, the quantity of Bifidobacterium and the Lactobacillusof the pouchitis model rats in the mucous membrane sample and the faeces sample were significantly decreased(P<0.05), and the Bacteroidetes, Faecalibacterium prausnitzii and 桛 Clostridium leptum subgroup in the mucous membrane of pouchitis were significantly decreased(P<0.05). The Clostridium coccoides group was the main flora in the mucous membrane of pouchitis, the bacterial diversity of non-puochitis group and control group was significantly higher than that of the puochitis group(P<0.05). Conclusions: The intestinal flora imbalance is one of the factors that cause the incidence of the pouhitis; this study provides a clue of the pathogenesis and treatment direction of the intestinal inflammatory disease.

GREEN BUILDING RATING FOR OFFICE BUILDINGS-LESSONS LEARNED

Office buildings constitute a significant proportion of the non-residential building stock.In recent years,various rating tools have been developed to foster green office building development.The Green Building Council of Australia(GBCA)has devel-oped the Green Star-Office rating tools for this purpose.There are an increasing number of stakeholders adopting these tools to showcase their efforts in sustain-able development.This research focuses on the challenges and barriers in obtain-ing GBCA ratings in Australian Office buildings.To accomplish this,the scoring sheets from the rating of 264 certified office buildings were collected and critically analysed.The findings indicated that credits related to the attributes of innovation,ecology and energy are comparatively difficult to achieve.It was also found in this study that a large number of projects did not apply for the specific credits of refrig-erant global warming potential,re-use of façade,topsoil and fill removal from site,and individual comfort control.This study provides a useful reference to both the property developer and the Green Building Council of Australia for green building developments in the future.In particular,the findings provide useful inputs to the development of the next generation of green building rating tools.

IMPACT OF DYNAMICAL HYDRATION SHELL AROUND HA PROTEIN ON NONLINEAR CONCENTRATION DEPENDENT T-RAYS ABSORPTION

T rays is sensitive to covalently cross linked proteins and can be used to probe unique dynamic properties of water surrounding a protein.In this paper,we demonstrate the unique abeorption properties of the dynamic hydnation shells deternined by hemagglutinin(HA)protein in ter-ahertz frequency.We study the changes arising fom diferent concentrations in detail and show that nonlinear absorption coefficient is induced by the dynamic hydration water.The binary and ternary component model were used to interpret the nonlinearity absorption behaviors and predict the thickness of the hydration shells around the HA protein in aquous phase.

Comparison of Clinical Effects of Abdominal Aortic Aneurysm Treatment with Open and Endovascular Techniques

Objective:To compare the therapeutic effects of endovascular and open surgery on abdominal aortic aneurysms.Methods:From June 2019 to May 2020,60 cases of abdominal aortic aneurysms(AAA)were divided into observation group(30 cases in endovascular technique group)and control group(30 cases in open technique group).Results:The blood loss,operative time and blood transfusion of the observation group were significantly lower than those of the control group(P<0.05).The incidence of postoperative complications is low,and the incidence of longterm complications is relatively high.Conclusion:In the treatment of abdominal aortic aneurysm,endovascular technology has the advantages of low risk,less trauma,and quick recovery after surgery.Open surgery is suitable for patients who cannot receive endovascular treatment.In order to achieve good treatment effects,it is necessary to choose an appropriate treatment method according to the actual situation of the patient.

Analysis on the Optimization of the P.E. Course Teaching Plan in Colleges and Universities

In the new period, the physical education in colleges and universities is of greater and greater significance for the enhancement of students＇ learning efficiency. In this paper, the current situation of the current physical education is analyzed, and also related suggestions on the optimization of the P.E. course teaching plan are proposed.

Application Effects of Total Percutaneous Technique in Endovascular Repair of Abdominal Aortic Aneurysm

Objective:To investigate the effectiveness of total percutaneous technique in endovascular repair of abdominal aortic aneurysm.Methods:Divide patients into two groups based on random tests.The control group received conventional treatment,and the experimental group received modified treatment.The changes in self-management ability,comfort level and recovery time before and after treatment were compared between the two groups.Results:The comfort level and self-management ability of the experimental group were significantly higher than that of the control group,and the recovery time was significantly shorter than that of the control group.The difference was statistically significant(P<0.05).Conclusion:Puncture suture can safely and effectively repair the intracavity of abdominal aortic aneurysm.

Application Study on Outdoor Teaching Practice in Physical Education

As outdoor sports are loved by more and more people, the introduction of outdoor sports to the EE. teaching practice plays a positive role in enriching the contents of student sports activities. In this paper, the meanings and characteristics of outdoor sports are introduced, the necessities for the outdoor RE. teaching practice are analyzed, and finally several suggestions on the construction of the outdoor teaching practice in physical education are proposed.

MAJOR FACTORS IMPEDING THE IMPLEMENTATION OF WASTE MANAGEMENT IN AUSTRALIAN CONSTRUCTION PROJECTS

This article aims to identify barriers to implementing waste management practices in construction projects and their interrelationship,based on the particular context of Australia.Interviews and a questionnaire survey were conducted as the primary data collection methods supported by the findings of a charrette.The findings reveal twenty critical barriers to implementing waste management practices in Australian construction projects.Four underlying factors that impede waste management prac-tices are extracted based on results of an exploratory factor analysis.These include rigidity of construction practices,construction project characteristics,awareness,experience and commitment,and the nascent nature of waste management.The study also finds that while both human factors and technical factors act as barriers to implementing waste management practices in Australian construction projects,human factors are more dominant.Thus,it is essential to address all these barriers in the early stage of construction projects for reducing waste generation.

ENERGY CONSUMPTION,ENVIRONM ENTAL IMPACTS AND EFFECTIVE MEASURES OF GREEN OFFICE BUILDINGS:ALIFE CYCLE APPROACH

The last few decades have witnessed a rapid development of green buildings in China especially the office sector.The life cycle assessment(LCA)approach has potential to weigh the benefits and costs associated with green building developments.Essentially,the LCA method evaluates the costs and benefits across a building’s life cycle with a system approach.In this study,a green office building in Beijing,China,was analyzed by life cycle assessment to quantify its energy use and evaluate the environmental impacts in each life cycle stage.The environmental impacts can be reduced by 7.3%,1.6%and 0.8%by using 30%gas-fired electricity generation,increasing the summer indoor temperature by 1℃,and switching off office equipment and lighting during lunchtime,respectively.Similarly,by reusing 80%of the selected materials when the building is finally demolished,the three major adverse environmental impacts on human health,ecosystem quality,and resource depletion can be reduced by 11.3%12.7%,and 7.1%respectively.Sensitivity analysis shows that electricity conservation is more effective than materials efficiency in terms of a reduction in environmental impacts.These findings are useful to inform decision makers in different stages of the green building life cycle.

Clinical profiles and outcomes of acute type A aortic dissection and intramural hematoma in the current era: lessons from the first registry of aortic dissection in China

Background::Acute type A aortic dissection(ATAAD)and acute type A intramural hematoma(ATAIMH)are life-threatening diseases with high mortality.To better understand their clinical features in the Chinese population,we analyzed the data from the first Registry of Aortic Dissection in China(Sino-RAD)to promote the understanding and management of the diseases.Methods::All patients with ATAAD and ATAIMH enrolled in Sino-RAD from January 1,2012 to December 31,2016 were involved.The data of patients’selection,history,symptoms,management,outcomes,and postoperation complications were analyzed in the study.The continuous variables were compared using the Student’s t test for normal distributions and the Mann-Whitney U test for non-normal distributions.Categorical variables were compared using the Chi-square test or Fisher exact test.Results::A total of 1582 patients with ATAAD and 130 patients with ATAIMH were included.The mean age of all patients was 48.4 years.Patients with ATAAD were significantly younger than patients with ATAIMH(48.9 years vs.55.6 years,P<0.001).For the total cohort,males were dominant,but the male ratio of patients with ATAAD was significantly higher compared to those with ATAIMH(P=0.01).The time range from the onset of symptom to hospitalization was 2.0 days.More patients of ATAIMH had hypertension than that of ATAAD(82.3%vs.67.6%,P<0.05).Chest and back pain were the most common clinical symptoms.Computerized tomography(CT)was the most common initial diagnostic imaging modality.84.7%received surgical treatment and in-hospital mortality was 5.3%.Patients with ATAAD mainly received surgical treatment(89.6%),while most patients with ATAIMH received medical treatment(39.2%)or endovascular repair(35.4%).Conclusions::Our study suggests that doctors should comprehensively use clinical examination and genetic background screening for patients with ATAAD and ATAIMH and further shorten the time range from symptoms onset to intervention,achieving early diagnosis and treatment,thereby reducing the mortality rate of patients with aortic dissection in China.We should standardize the procedures of aortic dissection treatment and improve people’s understanding.Meanwhile,the curing and transferring efficiency should also be improved.

Polyphenols from Securidaca inappendiculata alleviated acute lung injury in rats by inhibiting oxidative stress sensitive pathways

Objective:Securidaca inappendiculata is a medicinal plant frequently used in the treatment of inflammatory diseases in south China.In this study,we aimed to explore its bioactive constituent which contributes to the anti-inflammatory activity.Methods:Polyphenol-enriched and polyphenol-deprived fractions(PRF and PDF,respectively)were separated from the ethanolic extract by HPD300 macroporous resin-based method,and their antiinflammatory activities were investigated on a lipopolysaccharide(LPS)-induced acute lung injury(ALI)model in rats.The possible mechanism of action in alleviating acute inflammation was studied using RAW264.7 cells.Results:Both Folin-Ciocalteu and^(1)H nuclear magnetic resonance(NMR)analyses showed that polyphenolic content in PRF was approximately 10 times higher than that of PDF,and this observation reflected in their antioxidative capacities.PRF but not PDF significantly decreased the level of malondialdehyde,suppressed the expression of nicotinamide phosphoribosyltransferase(NAMPT)protein,and improved the severity of ALI in rats.PRF at 10μg/mL effectively downregulated the expression of proteins NAMPT,HMGB1,TLR4,and p-p65,and scavenged the intracellular reactive oxygen species(ROS)in LPS-primed RAW264.7 cells.N-acetyl-L-cysteine exhibited similar inhibitory effects on ROS production and NAMPT-mediated TLR4/NF-κB activation in vitro,whereas nicotinamide mononucleotide antagonized all the changes induced by PRF during cotreatments.Conclusion:As an antioxidant,PRF exhibited potent anti-inflammatory activity under both in vivo and in vitro conditions by downregulating NAMPT and TLR4/NF-κB.Accordingly,polyphenols were identified as important bioactive constituents in S.inappendiculata targeting oxidative stress-sensitive proinflammatory pathways.

Characteristics and application of road absorbing solar energy

If the heat of road surface can be stored in summer, the road surface temperature will be decreased to prevent permanent deformation of pavement. Besides, if the heat stored is released, it can supply heat for buildings or raise the road surface temperature for snow melting in winter. A road-solar energy system was built in this study, and the heat transfer mechanism and effect of the system were analyzed according to the monitored solar radiant heat, the solar energy absorbed by road and the heat stored by soil. The results showed that the road surface temperature was mainly affected by solar radiation, but the effect is hysteretic in nature. The temperature of the solar road surface was 3~C-6~C lower than that of the ordinary road surface. The temperature of the solar road along the vertical direction was 2~C-5~C lower than that of the ordinary road. The temperature difference increased as the distance to the heat transfer tubes decreased. The average solar collector efficiency of the system was 14.4%, and the average solar absorptivity of road surface was 36%.

Antihyperglycemic Effect of Various Fractions from Residues of Blumea balsamifera

Objective To evaluate the antihyperglycemic activities of various fractions from theresidues of Blumea balsamifera（BB）,and to properly utilize the waste resource.MethodsThe antihyperglycemic activities were evaluated by the suppression on serum glucose level in vivo andα-glucosidase inhibition assay in vitro.The high-,mid-,and low-dose（1,0.5,and 0.25 g/kg of the herb）fractions were ig given to mice for 8 d.The serum glucose was monitored at 1 and 12 h after feeding.Results The fasting and postprandial serum glucose levels of mice treated with high-dose petroleum ether fraction,ethyl acetate fraction,butyl alcohol fraction,methanol fraction,and water extract from BB were 4.45,4.39,4.43,4.15,3.74 mmol/L and 6.98,6.23,6.45,6.26,5.88 mmol/L,respectively,while those in vehicle control group were 5.63 and 7.50 mmol/L.There are four different inhibiting manners by the results ofα-glucosidase inhibition assay.Conclusion The residues of BB have anti-diabetes activities after steam distillation.

What leads to variations in the results of life-cycle energy assessment?An evidence-based framework for residential buildings

Residential buildings are one of the major contributors to climate change due to their significant impacts on global energy consumption.Hence,most countries have introduced regulations to minimize energy use in residential buildings.To date,the focus of these regulations has mainly been on operational energy while excluding embodied energy.In recent years,extensive studies have highlighted the necessity of minimizing both embodied energy and operational energy by applying the life-cycle energy assessment(LCEA)approach.However,the absence of a standardized framework and calculation methodology for the analysis of embodied energy has reportedly led to variations in the LCEA results.Retrospective research endeavoured to explore the causes of variations,with a limited focus on calculating embodied impacts.Despite the undertaken attempts,there is still a need to investigate the key parameters causing variations in LCEA results by examining methodological approaches of the current studies toward quantifications of embodied and operational energies.This paper aims to address three primary questions:‘what is the current trend of methodological approach for applying LCEA in residential buildings?’;‘what are the key parameters causing variations in LCEA results?’;and‘how can the continued variations in the application of LCEA in residential buildings be overcome?’.To this end,40 LCEA studies representing 157 cases of residential buildings across 16 countries have been critically reviewed.The findings reveal four principal categories of parameters that potentially contribute to the varying results of LCEAs:system boundary definition,calculation methods,geographical context,and interpretation of results.This paper also proposes a conceptual framework to minimize variations in LCEA studies by standardizing the process of conducting LCEAs.