Search

With the launch of the "Channel Computing Resources from the East to the West" project, Beijing-Tianjin-Hebei region, as a national integrated big-data center system, has established a Zhangjiakou data center cluster and continuously optimized the regional computing power layout. Beijing has been accelerating the construction of a global digital economy benchmark city since 2021, committed to forming a collaborative development pattern of computing power integration, and achieving a globally leading density of data centers. The core industry of Beijing's digital economy has strong fundamental advantages, but as a high-energy consuming industry, data centers cannot fully meet real-time computing power needs solely relying on the local infrastructure construction in Beijing. Therefore, this paper explored the promoting role of the Beijing-Tianjin-Hebei national integrated big-data center system in the construction of a global digital economy benchmark city in Beijing through channels such as computing power resource sharing, green energy consumption support, and industrial development collaboration. Based on this, it analyzed the challenges that still exist in current regional collaboration. [ABSTRACT FROM AUTHOR]

Since improvement of ultra-soft soil ground encounters the shortage of sand resources in Tianjin coastal area, non-sand blanket vacuum preloading method becomes an important substitute approach to solve the dilemma. Under such a background, DB/T 29-263—2019 Technical Standard of Non-sand Blanket Vacuum Preloading Method for Soft Soil Improvement in Tianjin was issued and implemented on July 1st in 2019. This paper compares the standard DB/T 29-263—2019 with the industrial standards, JTS 147—2017 Code for Foundation Design on Port and Waterway Engineering and JTS206—2017 Code for Foundation construction on Port and Waterway Engineering, and further analyzes the main differences in the design and construction with the conventional vacuum preloading method and the non-sand blanket vacuum preloading method for a purpose to help engineering practitioners better understand DB/T 29-263—2019 in the promotion of application of non-sand blanket vacuum preloading method. [ABSTRACT FROM AUTHOR]

Taking 13 cities in Beijing, Tianjin and Hebei as the research objects, this paper constructed the urban smart development index system from three aspects: smart space construction, smart element allocation and smart welfare performance, measured the urban smart development level in Beijing, Tianjin and Hebei from 2008 to 2018, and used ArcGIS software to realize the temporal and spatial measurement performance of smart development level. The obstacle degree model was used to reveal the criterion-level factors that hinder the smart development of Beijing, Tianjin and Hebei cities. The main conclusions are as follows: (1) The smart development level in Beijing, Tianjin and Hebei is low, the research period shows a weak fluctuation and downward trend, and there is room for improvement. (2) From the spatial difference of smart development level, the double core trend with Beijing and Tianjin as the high level is obvious, showing a downward trend from the center to the surrounding. (3) From the overall barrier performance of study area, smart welfare performance accounts for the largest proportion, smart space construction takes the second place, and smart factor allocation is the lowest. (4) The obstacles to smart development in different cities vary. The obstacles in Beijing and Tianjin are mainly focused on smart welfare performance. As the main core area to undertake Beijing's noncapital functions, smart space construction and smart element allocation are the obstacles in most cities. [ABSTRACT FROM AUTHOR]

(1) Background--As a significant ecological safeguard measure, the new round of returning farmland to forests project is of great ecological significance for ecological protection in Beijing and Tianjin. However, as a policy measure involving the withdrawal of farmers' cultivated land, whether it can guarantee the continuous in-crease of farmers' income and the stability of farmers' consumption is more worthy of discussion. (2) Methods--Based on the micro-panel data of 1115 farmers from 223 rural households in the "Beijing-Tianjin Sandstorm Source Treatment Project Monitoring" project from 2013 to 2017, this paper used the random effect model and the mediating effect model to study the impact of the new round of returning farmland to forests on the rural households' income and consumption and the effect mechanism on the rural households' consumption. (3) Results--The new round of returning farmland to forests significantly increased the total family income of the rural households, and had a significant positive impact on the total family income and operational income of the rural households at the level of 10%. However, the new round of returning farmland to forests did not improve the income structure of the rural households, and did not significantly affect the wage income, property income and transfer income of the rural households. The factors such as the farmers' education level and the number of migrant workers had a significant positive impact on the wage income. Overall, the income of the rural households was still dominated by operational income. The new round of returning farmland to forests significantly increased the total family consumption of the rural households, especially the basic consumption and productive consumption. However, there was no significant increase in children's education consumption, medical consumption and interpersonal communication consumption, which also indicated that the consumption structure of the rural households was still in basic consumption. The new round of returning farmland to forests had a positive impact on the rural households' consumption through the mediating variable of increasing the rural households' income, which verified the transmission mechanism that the farmers participated in the new round of returning farmland to forests to promote the increase of their income, and then affected their consumption. (4) Conclusions and Discussions--First, appropriately raise the subsidy standards and improve the compensation mechanism. Especially for areas prone to return to poverty and ecological functional areas, reasonable compensation standards can make up part of the losses caused by the farmers' participation in the project of returning farmland to forests. In addition, the government can implement a dynamic compensation mechanism according to the actual local situation, so that the subsidy standard is in line with the actual social and economic development situation. Second, actively promote the centralized utilization and circulation of the remaining finely fragmented land through the separation of the three rights of land. On one hand, the circulation of the fragmented land can improve the utilization rate of land, on the other hand, it can promote the flow of labor forces, so as to promote the increase of the rural households' income and the improvement of consumption structure. Third, actively implement the reform policy of forest rights, ensure clear rights to the rural households, and fully improve the promotion role of property rights income on the farmers' willingness to return farmland to forests. In addition, the farmers can also use forest rights as collateral to obtain loans to inject financial impetus into forestry production. Fourth, encourage the development of undergrowth economy and develop three-dimensional agriculture such as fruit industry, under-forest breeding industry, forage-grass planting industry, medicinal materials planting industry according to local conditions. However, while developing the corresponding undergrowth economy, we should also pay attention to the maintenance of forest nutrients, which is conducive to the sustainable and circular development of forestry. [ABSTRACT FROM AUTHOR]

Energy and electricity are the key area for China to achieve its dual-carbon goals. Precisely predicting future energy supply and demand and carbon emissions are beneficial for formulate a feasible path for low-carbon transition. The gray prediction model GM(1,1) is the most widely used dynamic prediction model in the field of energy forecasting, but it has higher requirements for original data and the model may fail when the development coefficient of GM(1,1) is large. On the other hand, another key parameter of GM(1,1), the gray effect u, directly determines the prediction accuracy of the model. If a better value of u can be found to be substituted into the model for prediction, the accuracy of the model will be significantly improved. Taking these into account problem, this paper introduced into the optimization process of the gray prediction model a novel swarm intelligence algorithm, namely the Monarch Butterfly Optimization (MBO) that performs well in actual optimization problems. The newly proposed gray-monarch butterfly prediction model can achieve accurate predictions of Tianjin's energy supply and demand and carbon emissions. Based on the prediction results, a low-carbon transition path for Tianjin's carbon peak in 2030 was formulated. Compared with existing classic literature methods and prediction data, the effectiveness and superiority of the grey-monarch butterfly optimized forecasting model proposed in this paper were discussed. [ABSTRACT FROM AUTHOR]

Under the guidance of the new-type urbanization concept (which highlights rational layout, harmony, and livability), the mixed-use residential area can avoid the problems found in the single-function communities. These include inconvenience in daily life, separation of workplace and residence, space separation, and environmental pollution. Moreover, residential areas conform to the urban development trend and meet residents' needs in their daily life. Based on the field investigation and statistical study of 24 mixed-use residential areas in Tianjin, this paper explores the general rules of the mixed-use residential area's functional composition. Results reveal that it is 50%~70% used for residential functions for the mixed-use residential area and 30%~50% used for industrial functions. Based on the above analysis, this paper puts forward suggestions and a discussion to provide a reference for the formulation of norms and development and construction of the mixed-use residential area. [ABSTRACT FROM AUTHOR]

Automobile manufacturing industry is one of the basic industries in the national emerging economy. An automobile manufacturing plant includes four workshops: stamping, welding, painting and final assembly workshops. Automobile coating workshop is a workshop with a high degree of automation in the process of automobile manufacturing. Nowadays, the production mode of automobile industry has changed from batch production to customer order production, thus traditional automobile production lines can no longer meet the individual needs of automobile production. Therefore we designed a flexible automobile coating production control system based on RFID and fieldbus technology. This paper introduces the related functions of the automobile coating control system in detail, which mainly includes video monitoring system, body identification system, safety lamp system, production control system and production management system. The automobile coating control system has been put into operation in Tianjin for 3 years, and the control effect is good. [ABSTRACT FROM AUTHOR]

Agricultural eco-efficiency is an important index to measure the sustainable development of agriculture. Scientific evaluation of agricultural eco-efficiency is necessary to accurately assess the true level of agricultural ecosystems, so as to achieve efficient utilization of agricultural resources. In this paper, the super-efficiency SBM-DEA model was adopted to measure and group the agricultural ecoefficiency of 31 provinces in Chinese inland from 2000 to 2017. The results showed that the provinces in the high-efficiency group were located in the eastern and western region, while the provinces in the middle and low efficiency groups were located in the northeast and central regions and parts of the western region. In 2017, only Qinghai, Ningxia, and Tianjin had insufficient agricultural output. The remaining areas that did not achieve DEA efficiency all had different degrees of redundancy of input and excessive carbon and pollution emissions. The spatial difference of China′s agricultural eco-efficiency was obvious, and the trend of development changes was different. The main reasons for the efficiency loss were the redundancies of inputs and the excessive undesired output. Therefore, each province should take appropriate measures to improve the agricultural eco-efficiency according to its actual situation and the specific causes for efficiency loss. [ABSTRACT FROM AUTHOR]

Laser particle analysis method has the advantages of simple operation, fast testing speed and good repeatability in the geotechnical particle analysis test. Compared with traditional hydrometer method, it has great advantages, but the relationship between the two methods needs further verification. In this paper, the typical soft soils in Tianjin Port and Lianyungang area of China were selected to carry out particle analysis tests using hydrometer method and laser particle analysis method, and the difference and correlation of the test results are analyzed. The results show that: compared with the hydrometer method, the colloidal particle content (< 0.002 mm) and sand particle content (>0.075 mm) measured by laser particle size analyzer method have some differences, the clay content(< 0.005 mm), powder content(0.005-0.075 mm) and D50 are basically the same; the results of each fractions measured by the two methods have significant linear correlation, especially for the clay content and D50, the corresponding linear regression equation can be established to transform each other. [ABSTRACT FROM AUTHOR]

Land use changes can affect the ecosystem services. Since the implementation of reform and opening- up policy in 1978, the transformation and development of society and economy has led to the land use transition, and furthermore led to the "ecosystem services transition". Based on the data of LUCC, net primary productivity (NPP) and statistics in 1980, 2000 and 2015, this paper analyzed the changes and spatial patterns of two types of ecosystem service, e.g., food production, carbon sequestration and oxygen release, in the Beijing-Tianjin- Hebei region by using the methods of GIS and ecosystem service values calculation, and revealed the reasons for the "ecosystem services transition". The results show that: (1) In the past 35 years, the land use changes in the study region was mainly characterized by the expansion of construction land and the decrease of cultivated land. The phenomenon of conversion of cultivated land to construction land was particularly prominent in this region. Between 1980- 2000 and 2000- 2015, the cultivated land in mountainous areas changed from decrease to increase and the forest land changed from decrease to increase. The cultivated land in dam areas continued to increase and the forest land changed from decrease to increase. Both the cultivated land and forest land in plain area continued to decrease. In 1980 and 2000, areas with high values of NPP were mainly located in mountainous areas, and in 2015, they were mainly found in plain areas. (2) From 1980 to 2000, the ecosystem services in the study area were mainly reflected by the increase of food production service and the decrease of carbon sequestration and oxygen production service. From 2000 to 2015, the ecosystem services in the region were mainly featured by the simultaneous increase of food production function and carbon sequestration and oxygen production function. The pattern of "ecosystem service transition" was "food production + carbon sequestration and oxygen production - " → "food production + carbon sequestration and oxygen production + ". (3) The main reasons for "ecosystem services transition" were the improvement of agricultural productivity, the increase of area and quality of forest land, and the increase of the quality of cultivated land and grassland. In general, the "ecosystem services transition" in the Beijing-Tianjin- Hebei region has a positive impact on food security. It is particularly necessary to pay attention to areas where both food production function and ecological function declined. Policies aimed at improving agricultural productivity should be formulated, while policies for supporting ecological restoration should be continued. [ABSTRACT FROM AUTHOR]

Traditional hydraulic project construction is greatly affected by external conditions during construction, especially the water concrete pouring, the quality is not easy to ensure and the risk is high. Therefore, to minimize the water work will be the breakthrough of increasing benefit of hydraulic project. Based on the construction project of sea drainage outlet construction of No. 6 and No. 7 general berths in the grain and oil area of Dagukou Port Area of Tianjin Port, inspired by the completed dry construction method of the shore-landing structure, break through the traditional construction model, an innovative dry construction method of pipe surround concrete is proposed. The method has successfully saved the cost and improved the benefit of the project.'This paper analyzed the construction method from the aspects of cost, quality and safety, which has a high promotion value. [ABSTRACT FROM AUTHOR]

Traditional hydraulic project construction is greatly affected by external conditions during construction, especially the water concrete pouring, the quality is not easy to ensure and the risk is high. Therefore, to minimize the water work will be the breakthrough of increasing benefit of hydraulic project. Based on the construction project of sea drainage outlet construction of No. 6 and No. 7 general berths in the grain and oil area of Dagukou Port Area of Tianjin Port, inspired by the completed dry construction method of the shore -landing structure, break through the traditional construction model, an innovative dry construction method of pipe surround concrete is proposed. The method has successfully saved the cost and improved the benefit of the project. This paper analyzed the construction method from the aspects of cost, quality and safety, which has a high promotion value. [ABSTRACT FROM AUTHOR]

We establish a Rosen-Roback spatial equilibrium model which decomposes the total economic growth into the change of labor input, total factor productivity (TFP) and wage differences. We calculate the model-based contribution of the cities, especially megacities, to Chinese aggregate economy. By using data of 285 cities from 2002 to 2015, we find out that the model-based contribution of Shanghai, Shenzhen, Beijing and Guangzhou to aggregate growth turn out to be higher than what is simply inferred from the share in GDP. Factor decomposition shows that the positive impact of megacities on Chinese economy comes from the increase in TFP and the increase in labor input, while the megacities widen wage dispersion of the whole country, generating a negative effect on economic growth. "Counterfactual" studies show that for the period 2002-2015, the top-five megacities increase the Chinese aggregate economy by 25.33%, and if the top-five did not enlarge the wage dispersion, then the aggregate economy would increase by 40.42%. Our research also shows that the overall development of the Yangtze River Delta and the Pearl River Delta regions is more balanced, while the Beijing-Tianjin-Hebei region still have a long way to go to reach the coordinated development. Since no previous study has used city level data in China to analyze the impact of megacities on Chinese economy, our research will fill this gap. According to the empirical results, this paper puts forward two suggestions, one is to further reduce the wage dispersion in China, the second is to further coordinate the Beijing-Tianjin-Hebei region for more balanced development. [ABSTRACT FROM AUTHOR]

For detecting rational bubbles, via relaxing the coefficient constraints of switching regression model, the paper proposes a more efficient model, autoregressive (AR) switching model, and gives the estimation method. An application to seasonally Chinese housing price data in the first decade of 21 century shows the model is more efficient than switching regression model, and provides evidence of bubbles in Beijing and Shanghai, but no evidence of bubbles in Tianjin and Chongqing. Further more, the probabilities of being in survival state show that the real estate-related policies of Chinese government have ruled out bubbles in Beijing, but not in Shanghai. The proposed model can also be used to detect rational bubbles with regime switching structures in other assets. [ABSTRACT FROM AUTHOR]

Logistics cost control is always an academic and business circles' hot topic and the enterprise can effectively reduces business costs by controlling this "black continent". This paper built the structure model of manufacturing enterprise's logistics operational cost, and simulated the model: a case study of Tianjin handicraft firm, finally proposed some optimizational tactics. The research results indicated that the complex relation among factors of manufacturing enterprise's logistics operational cost system could be better revealed with the use of system dynamics methodology and the method proposed can provide guides and references for logistics cost control. [ABSTRACT FROM AUTHOR]

Taking the project of the A and B area ultra-high-level building of TeDa square in Tianjin as background, cyclic loading tests on six full scale square CFT column to H-shape steel beam joint specimens containing four different kinds of joint of details were carried out. The basic situation and failure characteristics of all specimens were introduced. The bearing capacity, ductility and energy dissipation capacity, stiffness degradation and strength degradation of four kinds of joints were compared. Test results show that, if the quality of welding and installation can be ensured, all four kinds of joints have high bearing capacity and good seismic behavior. Welding reinforcing plates on both sides of the beam flange contributes to the joint bearing capacity. Filling concrete in the rectangular pipe is useful for reducing shear deformation and improving strength and rigidity of cores of beam-column joints. In addition, ANSYS 10. 0 was used to simulate the hysteretic behavior of the specimens and the nonlinear analysis was carried out. The results of theoretical analysis were compared with the test results. It indicates that the force-displacement curve obtained from nonlinear finite element analysis agrees well with the test result. The connection between concrete-filled rectangular steel tube column and steel beam discussed in the paper has good capability of energy consumption. [ABSTRACT FROM AUTHOR]