Research Progress and Trends of Urban Public Facilities' Location

Urban development in China has recently encountered various problems,and many of these problems have been caused by uneven distribution of public facilities in different districts,so it is signifi cant to choose reasonable locations for urban public facilities. Current researches on location of urban public facilities in China cover various aspects,involve different units,show diverse features,and make outstanding contributions. However,these researches have also obvious limitations. The future study on public facilities' location will focus on specifi c application of the model in different cities,or better consider characteristics of the city.

Pseudo-Dynamic Testing for Seismic Performance Assessment of Buildings with Seismic Isolation System Using Scrap Tire Rubber Pad Isolators

Investigation of seismic performance of buildings with STRP （scrap tire rubber pad） seismic isolators by means of pseudo-dynamic tests and numerical simulation is presented. The isolated building is numerically modeled, while the base isolation layer is considered as the experimental substructure in the pseudo-dynamic tests. The test result verifies that the STRP isolator shows acceptable shear deformation performance predicted by the design methods, and demonstrated that seismic isolation using STRP works as a protective measure to provide enhanced seismic performance of the building indicated by the reduction of top floor absolute acceleration, drift and base shear as designated.

Lateral load performance and seismic demand of unbonded scrap tire rubber pad base isolators

The scrap tire rubber pad(STRP)made by natural or synthetic rubber and high strength reinforcing cords exhibits substantial vertical stiffness and horizontal flexibility,and these properties can be regarded as suitable for seismic isolators for structures.The use of environmentally burdensome scrap tires as STRP isolators might be convenient as an efficient and low-cost solution for the implementation of aseismic design philosophy for low-to-medium rise buildings,especially in developing countries.Finite element analyses of unbonded square and strip-shaped STRP isolators subjected to a combination of axial and lateral loads are conducted to investigate its lateral deformation performance under seismic loading.The rubber of the isolator is modelled with Mooney-Rivlin hyperelastic and Prony viscoelastic materials,including the Mullins material damage effect.The influence of the length-to-width ratio and bearing height on the isolator performance is assessed in terms of the force-displacement relationship,horizontal stiffness,damping,and isolation periods.It is shown that the dependence of stiffness on the length-to-width ratio is significant in the longitudinal direction and minor in the transverse direction.The STRP isolators following the proposed design criteria are shown to satisfy the performance requirement at different levels of seismic demand specified by the ASCE/SEI 7-2010 seismic provisions.

Performance Evaluation of Food and Beverage Listed Companies in Vietnam

During the last decade,the food and beverage industry has been one of the most significant and prioritized industries that contributed to the economic growth in Vietnam.Therefore,how to enhance the performance of food and beverage firms has become a critical factor for Vietnam’s economic development.This research aims to use the data envelopment analysis(DEA)and the Malmquist productivity index(MPI)to assess changes in operational performance and productivity of listed lead food and beverage firms in Vietnam during the period between 2015 and 2020.The obtained results reveal that Vietnamese food and beverage firms were generally inefficient between 2015 and 2020 because the number of relatively inefficient companies was higher than the relatively efficient ones in each year between 2015 and 2020.The MPI findings indicate the growth in productivity during the study period as a result of technological progress.By integrating the findings of the relative efficiency and productivity change,this study creates five decision-making matrixes for five periods,respectively,from 2015 to 2020 to position the food and beverage firms in each sector.The analytical results provide instructions to senior managers on developing strategy for increasing efficiency of food and beverage listed companies in Vietnam.

Swelling Properties of Water-Swelling Materials Exposed to Organic Water Pollution

A water-swelling material is one of the rubbery impermeable materials which mixed synthetic resin elastomers as a base material, high absorbency polymers, filler and solvents. In this study, swelling characteristics of the water-swelling material on the water polluted with COD and BOD, as an impermeable material at coastal landfill sites, are examined by laboratory swelling ratio test. Furthermore, the factor in which it influences the swelling pressure of water-swelling material is clarified by measuring the swelling pressure. As the results, the COD nor the BOD concentrations in the soaked water influence the swelling ratio of the water-swelling material. When the thicknesses of water-swelling material are 2 mm and 3 mm, the maximum swelling pressure of 0.5 MPa or more that corresponds to hydraulic pressure by depth of 50 m is possessed.

On Internet and Government Service from the Perspective of Good Governance Theory

The 13th Five-Year Plan and the government work report have repeatedly referred to the ＂Intemet＋ government services＂ to achieve data sharing, public interaction, government and enterprise win-win, political and social, and this is precisely the concept of good governance Together However, the Intemet＋ government services is not the 2.0 version of e-government, but the new interactive experience, is no longer the original government unilateral government information disclosure and online services, but the government, society, business tripartite link Require the Government to do the top design at the same time, but also to change the concept, put down the shelves to the enterprise to leam, with the cooperation, while the policy, service and implementation of the real arrival of the community and citizens.

Optimisation of a Bus Network Configuration and Frequency Considering the Common Lines Problem

Public transportation network reorganisation can be a key measure in designing more efficient networks and increasing the number of passengers. To date, several authors have proposed models for the “transit route network design problem” (TRNDP), and many of them use a transit assignment model as one component. However, not all models have considered the “common lines problem,” which is an essential feature in transit network assignment and is based on the concept that the fastest way to get to a destination is to take the first vehicle arriving among an “attractive” set of lines. Thus, we sought to reveal the features of considering the common lines problem by comparing results with and without considering the problem in a transit assignment model. For comparison, a model similar to a previous one was used, formulated as a bi-level optimisation problem, the upper problem of which is described as a multi-objective problem. As a result, although the solutions with and without considering the common lines showed almost the same Pareto front, we confirmed that a more direct service is provided if the common lines problem is considered whereas a less direct service is provided if it is not. With a small network case study, we found that considering the common lines problem in the TRNDP is important as it allows operators to provide more direct services.

Applicability of Mean Field Approximation to Numerical Experiments of Thermal Convection during the Cooling Period of Lake Biwa

This paper describes the applicability of a stochastic model to the numerical experiments of thermal convection carried out under the condition of the northern part of Lake Biwa, Shiga Prefecture, Japan. It was shown in the previous study that the temporal changes of vertical water temperature distributions during the cooling period between September and February can be reproduced by a simple 3D-CFD model. It was also pointed out that the spatial distributions of cooled water body sinking to the bottom due to water surface cooling represent similar features of forest gap distribution, which can be clarified by a stochastic model. The basic features of numerical experiments on thermal convection such as the spatial distribution of cooled water body are firstly shown with several cooling rates at water surface. Then, a stochastic model, which was originally introduced to explain forest gap dynamics, is shown with its MFA （mean field approximation） as first approximation of stochastic model. It is pointed out through the comparison of theoretical results by MFA with tuned model constants to numerical experiments that MFA with some refinement can be applicable to reproduce the basic features of simulated results to some extent, although further investigations are required to clarify the applicability of the model to more detailed mechanism of thermal convection such as size distribution of cooled water body, phase change of flow pattern, etc..

Numerical modeling for the coupled thermo-mechanical processes and spalling phenomena in sp Pillar Stability Experiment (APSE)

In this paper, the coupled thermo-mechanical （TM） processes in the AEspoe Pillar Stability Experiment （APSE） carried out by the Swedish Nuclear Fuel and Waste Management Company （SKB） were simulated using both continuum and discontinuum based numerical methods. Two-dimensional （2D） and three- dimensional （3D） finite element method （FEM） and 2D distinct element method （DEM） with particles were used. The main objective for the large scale in situ experiment is to investigate the yielding strength of crystalline rock and the formation of the excavation disturbed/damaged zone （EDZ） during excavation of two boreholes, pressurizing of one of the boreholes and heating. For the DEM simulations, the heat flow algorithm was newly introduced into the original code. The calculated stress, displacement and temperature distributions were compared with the ones obtained from in situ measurements and FEM simulations. A parametric study for initial microcracks was also performed to reproduce the spalling phenomena observed in the APSE.

Leachate Control Technology Using H-Jointed Steel Pipe Sheet Piles with H-H Joints at Coastal Landfills

H-H joint of ＂H-jointed SPSP with H-H joint＂, which is made up of interlocking two H-steel sections of different sizes, is the one of SPSP＇s joint to improve the hydraulic conductivity. ＂H-H jointed SPSP with H-H joint＂ is expected to be applied to a vertical cutoff wall in coastal landfill sites. In H-jointed SPSP with H-H joint, the H-joint is completely imperviousness. H-H joint, however, is pervious at interlocked state because a gap of 8 to 11 mm is left between the interlocking flanges, therefore, a water interception treatment must be conducted to seal the gap. The water shielding treatment of H-H joint is executed by coating the gaps with a water-swelling sheet of paint before its installation. Then, hollow space is generated in H-H joint after treating by water-swelling sheet, and that space can be used effectively. This paper proposes leachate control technologies using H-H joint interior space of SPSP cutoff walls. The possibility of those technologies and hydraulic conductivity of H-jointed SPSP with H-H joints are demonstrated by conducting the hydraulic conductivity test.

Model-based offline reinforcement learning framework for optimizing tunnel boring machine operation

Research on automation and intelligent operation of tunnel boring machine(TBM)is receiving more and more attention,benefiting from the increasing construction data.However,most studies on TBM operations optimization were trained by the labels of human drivers’decisions,which were subjective and stochastic.As a result,the control parameters suggested by these models could hardly surpass the performance of a human driver,even the possibility of subjective incorrect decisions.Considering that the geomechanical feedback to TBM under drivers’actions is objective,in this paper,a transformer-based model called the geological response for tunnel boring machine(GRTBM),is proposed to learn the relationship between operation-adjust and TBM monitoring changes.Additionally,with the model-based offline reinforcement learning,this paper provided a novel approach to optimizing the TBM excavation operations.The decision processes,recorded in the Yin-song TBM project for a waterway tunnel in Jilin Province of China,were used for the validation of the model.By adopting an implicit perception of geological conditions in the GRTBM model,the suggested method achieved the desired state within a single action,greatly outperformed the practical adjustments where 500 s were taken,revealing the fact that the proposed model has the potential to surpass the capability of human beings.

Extracting Natech Reports from Large Databases: Development of a Semi-Intelligent Natech Identification Framework

Natural hazard-triggered technological accidents(Natechs)refer to accidents involving releases of hazardous materials(hazmat)triggered by natural hazards.Huge economic losses,as well as human health and environmental problems are caused by Natechs.In this regard,learning from previous Natechs is critical for risk management.However,due to data scarcity and high uncertainty concerning such hazards,it becomes a serious challenge for risk managers to detect Natechs from large databases,such as the National Response Center(NRC)database.As the largest database of hazmat release incidents,the NRC database receives hazmat release reports from citizens in the United States.However,callers often have incomplete details about the incidents they are reporting.This results in many records having incomplete information.Consequently,it is quite difficult to identify and extract Natechs accurately and efficiently.In this study,we introduce machine learning theory into the Natech retrieving research,and a Semi-Intelligent Natech Identification Framework(SINIF)is proposed in order to solve the problem.We tested the suitability of two supervised machine learning algorithms,namely the Long ShortTerm Memory(LSTM)and the Convolutional Neural Network(CNN),and selected the former for the development of the SINIF.According to the results,the SINIF is efficient(a total number of 826,078 records were analyzed)and accurate(the accuracy is over 0.90),while 32,841 Natech reports between 1990 and 2017 were extracted from the NRC database.Furthermore,the majority of those Natech reports(97.85%)were related to meteorological phenomena,with hurricanes(24.41%),heavy rains(19.27%),and storms(18.29%)as the main causes of these reported Natechs.Overall,this study suggests that risk managers can benefit immensely from SINIF in analyzing Natech data from large databases efficiently.

The role of dilatancy in shallow overburden tunneling

The mechanical behavior of sandy ground during shallow circular tunneling is explored for various overburden heights H(=0.5D,1.0D,1.5D and 2.0D;D is the diameter of the tunnel)and various dilatancy coefficients(w//=0,1/3,1/2,and 1;/and w are the internal friction angle and dilation angle,respectively)through finite difference analyses.The ground is modeled as a linear elastic-perfectly plastic material that employs the Mohr-Coulomb yield criterion and obeys the non-associated flow rule.The ground reaction curve is applied in conjunction with the stress path as a conceptual tool for interpreting the mechanical response of the ground to tunneling.It is revealed that,at a certain relaxation value,a yield zone develops during tunneling and extends to the surface.This relaxation value increases with increases in the overburden and w//values for the cases of less shallow tunnels(i.e.,H=1.0D,1.5D and 2.0D),while for the shallowest case(H=0.5D),the extent of the yield zone to the ground surface is not sensitive to the w//value.The shear strain due to tunneling also increases with an increase in the w//value.Moreover,the w//value affects the radial displacement and the surface settlement due to tunneling.The magnitudes of the surface settlement and the radial displacement at the tunnel crown both decrease with an increase in the w//value.The relative difference in the displacement at the tunnel crown between the upper bound and lower bound values,w//(at the last computed stage),increases with an increase in the overburden height.It is recommended,therefore,that careful consideration be given to the dilatancy angle in the case of relatively less shallow tunnels.

Deformation behavior and acting earth pressure of three-hinge precast arch culvert in construction process

The three-hinge precast arch culvert consists of two segmental precast units and three hinge points.It harnesses the passive resistance of an embankment by permitting deflection,resulting in a mechanically stable structure.However,the design of the three-hinge precast arch culvert differs from that of a conventional culvert,prompting the mechanical behavior of the culvert to become an important issue.In this study,therefore,1/5 scale model tests were conducted on a three-hinge precast arch culvert to measure the changes in the inside width and earth pressure acting on the culvert at each step in order to investigate the culvert’s mechanical behavior at each construction stage.Moreover,the deflection measurement of the culvert was obtained at the in-situ construction site.The results indicate that the arch members were displaced according to the embankment depth in a similar manner to the design load.Therefore,the horizontal earth pressure,which was larger than the earth pressure at rest,acted on the culvert at the end of its construction.

Discussion on the mechanism of ground improvement method at the excavation of shallow overburden tunnel in difficult ground

Tunnel construction opportunities involving shallow overburdens under difficult(e.g.,soft,unconsolidated)grounds have been increasing in Japan.Various auxiliary methods for excavating mountain tunnels have been developed and can satisfy stringent construction requirements.The ground improvement method,which is one of the auxiliary methods for shallow overburden tunnels,has demonstrated its ability to effectively control the amount of settlement under soft ground.However,the mechanism of the ground improvement method has not been clarified,nor has a suitable design code been established for it.Therefore,because the strength of the improved ground and the suitable length and width of the improved area have not been fully understood,an empirical design has been applied in every case.In this paper,the mechanical behavior during the excavation,including that of the stabilized ground,is evaluated through trapdoor experiments and numerical analyses.In addition,the enhancement of tunnel stability resulting from the application of the ground improvement method is discussed.

Phosphorus recovery from municipal and fertilizer wastewater:China's potential and perspective

Phosphorus（P） is a limited resource, which can neither be synthesized nor substituted in its essential functions as nutrient. Currently explored and economically feasible global reserves may be depleted within generations. China is the largest phosphate fertilizer producing and consuming country in the world. China’s municipal wastewater contains up to 293,163 Mg year of phosphorus, which equals approximately 5.5% of the chemical fertilizer phosphorus consumed in China. Phosphorus in wastewater can be seen not only as a source of pollution to be reduced, but also as a limited resource to be recovered. Based upon existing phosphorus-recovery technologies and the current wastewater infrastructure in China, three options for phosphorus recovery from sewage sludge, sludge ash and the fertilizer industry were analyzed according to the specific conditions in China.

Relationship between Remotely Sensed Vegetation Change and Fracture Zones Induced by the 2008 Wenchuan Earthquake, China

The Wenchuan earthquake triggered cascading disasters of landslides and debris flows that caused severe vegetation damage. Fracture zones can affect geodynamics and spatial pattern of vegetation damage. A segment tracing algorithm method was applied for identifying the regional fracture system through lineament extractions from a shaded digital elevation model with 25 m mesh for southern Wenchuan. Remote sensing and geographic information system techniques were used to analyze the spatiotemporal vegetation pattern. The relationship between vegetation type identified from satellite images and lineament density was used to characterize the distribution patterns of each vegetation type according to fracture zones. Broad-leaved forest, mixed forest, and farmland persist in areas with moderate lineament density. Deciduous broad-leaved and coniferous forest persists in less frac- tured areas. Shrub and meadow seem to be relatively evenly distributed across all lineament densities.Meadow, farmland, and shrub persist in the fractured areas. Changes of spatial structure and correlation between vegetation patterns before and after the earthquake were examined using semivariogram analysis of normalized difference vegetation indices derived from Landsat enhanced thematic mapper images. The sill values of the semivariograms show that the spatial heterogeneity of vegetation covers increased after the earthquake. Moreover, the anisotropic behaviors of the semivariograms coincide with the vegetation changes due to the strikes of fracture zones.

Appetite for Natech Risk Information in Japan:Understanding Citizens'Communicative Behavior Towards Risk Information Disclosure Around Osaka Bay

Effective risk communication is essential for disaster risk management.Apart from empowering communities to make informed risk choices,risk information disclosure can also drastically enhance their disaster preparedness,especially concerning conjoint scenarios of technological and natural hazards(Natech).A fundamental precondition is the actual demand for such information.This study ventures to assess whether residents around Osaka Bay have this demand,or"appetite,"for risk information disclosure,as well as to understand their communicative behavior and perceived challenges in the Japanese context through the prism of the Situational Theory of Problem Solving.To test this framework under realistic conditions,data were collected through a household questionnaire survey from two urban areas near industrial complexes in Osaka Bay.The results show that identifying Natech risk information deficiency as a problem was not a statistically significant predictor for individuals'motivation to communicate.However,their motivation increased as their perceived personal involvement with the situation rose,while the perceived obstacles in doing something about it exerted a negative influence on their motivation.Individuals'motivation intensified their communicative actions to solve this problem.Public segmentation underscored the elevated public perceptions concerning the issue of risk information deficiency in nearly nine out of ten respondents.These findings indicate a strong community appetite for chemical and Natech risk information,which subsequently led to high situational motivation to engage in communicative action,particularly information acquisition.Risk management policy is suggested to focus on introducing chemical risk information disclosure regulatory initiatives to encourage citizen engagement.