Double-difference Method Research Articles

Evaluation method of sustainable utilisation level of agricultural land resources based on double difference method

Evaluation method of sustainable utilisation level of agricultural land resources based on double difference method

ФОРМУВАННЯ ШВИДКІСНОЇ МОДЕЛІ І ТЕОРЕТИЧНІ ОСНОВИ МЕТОДІВ ВИЗНАЧЕННЯ ГІПОЦЕНТРУ МІКРОСЕЙСМІЧНОЇ ПОДІЇ ПРИ ПРОВЕДЕННІ ГІДРОРОЗРИВУ ПЛАСТА

The article is devoted to the analysis of the characteristics of the determining stages of data processing of microseismic monitoring of hydraulic fracturing. The importance of having an accurate velocity model and the stages of its creation are substantiated. A classification of velocity models and the input data required for their creation are provided. Groups of methods for determining the hypocenter of a microseismic event, their advantages, limitations and factors affecting the accuracy of calculations are considered. A detailed description of specific methods is given. Among the absolute methods are grid search methods, linearized inversion (Geiger) and methods based on the extension of wave fields into the medium. Among the relative methods are the master-event method and the double-difference method. Algorithms for the application of specific methods are given. An example of the comparative characteristics of various methods when choosing a method for determining the hypocenter of a microseismic event is provided.

A comparative study on the effects of high-speed rail and ordinary rail on regional economic growth—empirical research based on DlD model

Today, high-speed rail has become an indispensable means of transportation in people's production and life. However, after the opening of the high-speed rail, the development of ordinary railways has also become an object of concern, and the impact of high-speed rail on ordinary railways is worth studying from an empirical perspective. This article takes more than 2,000 counties and cities in China as the research object, using the data from 2004 to 2018, using the double difference method to analyze the impact of high-speed railway construction and ordinary railway construction and further fitting the relationship between high-speed railway and ordinary railway. The research results show that: the opening of high-speed railways has a negative effect on the regional economy; the opening of ordinary railways has a positive effect on the regional economy. By analyzing the interaction effect of the opening of high-speed rail and ordinary railway, it can be concluded that the opening of high-speed rail has a restraining effect on the impact of ordinary railway on regional economic development.

Will Local Financial Development Affect the Competitive Advantage of Chinese Enterprises' Exports?

Many studies confirm the impact of financial development on the macro economy, but systematic studies of the impact of financial development on corporate exports is still lacking. Based on the quasi-natural experiment established by city commercial banks, this paper uses micro-data of Chinese industrial enterprises from 1998 to 2013 and adopts a double difference method to test the impact of the development of local financial institutions on corporate exports. The results show that the establishment of city commercial banks has significantly increased the export participation rate and total export volume of manufacturing enterprises in the city where they are located; comparatively speaking, its impact on the export expansion margin of industrial enterprises exceeds the intensive margin. At the same time, the study also found that the above-mentioned influences exist in both long-term and short-term, and in enterprises of different sizes and attributes. These findings provide new evidence for understanding the relationship between local financial development and corporate exports.

THE IMPACT OF TRADE POLICY UNCERTAINTY ON THE QUALITY OF CHINA'S MANUFACTURING EXPORTS: AN EMPIRICAL STUDY BASED ON CHINA'S EXPORTS TO THE UNITED STATES

Previous studies believe that the decline in trade policy uncertainty will lead to a decline in the quality of export products, mainly because the decline in trade policy uncertainty is mainly reflected in the decline in tariff levels, so that enterprises that produce a large number of low-quality products are easier to enter the export market, but China's medium and high-tech products even in the case of tariff decline, due to weak competitiveness, so the export quantity is relatively small, so the overall average quality of export products declines. This paper uses China's export trade with the US manufacturing industry from 2000 to 2013 as the object, uses the double difference method to verify the impact of trade policy uncertainty on China's manufacturing products, and deeply explores the differences in manufacturing at different technology levels. The study finds that, unlike previous studies, this paper finds that the decline of trade policy uncertainty is conducive to the improvement of manufacturing export product quality, mainly because fierce market competition will force the manufacturing industry to improve the quality of export products, and the study also finds that the decline of trade policy uncertainty mainly promotes the improvement of product quality of low-tech manufacturing products, and has little impact on the manufacturing industry with medium and high technology levels.

Higher Education Expansion and Population Mobility

China has implemented a higher education expansion policy since 1999, increasing the number of higher education institutions and increasing the number of expansions. This paper uses panel data and intensity double difference method for 31 provinces in China from 1996 to 2020 for the analysis. It is found that the higher education expansion policy has increased the level of population mobility, especially for the southeastern coastal and economically developed regions. Further mechanism tests show that after the implementation of higher education expansion policy, regions increase investment in education and enrich education resources, but also widen the economic gap between regions, triggering factor endowment and neoclassical growth mechanisms, which affect population mobility. This paper suggests increasing funding for higher education in regions with weaker economic development, slowing down the expansion of higher education in economically developed regions, and strengthening inter-university cooperation.

Time-differenced double difference method for measurement of Navigation with Indian Constellation (NavIC) receiver differential phase bias

The pseudo-range (PR) and carrier phase (CP) observations of Global Navigation Satellite System (GNSS)/Navigation with Indian Constellation (NavIC) receivers are influenced due to various errors like ionosphere delay, troposphere delay, receiver and satellite clock error, multipath, integer ambiguity, receiver hardware noise etc. However, the real-time positioning and navigation applications are in quest of high-quality carrier phase measurements with zero bias. The GNSS/NavIC receiver hardware noise is one of the critical error sources that degrade the quality of carrier phase measurements. And it can be measured by computing the differential phase bias or carrier phase bias employing the double-difference method. This research article proposes a novel approach called Time Differenced Double Difference Carrier Phase (TDDDCP) for estimating differential phase bias or carrier phase bias of NavIC receiver. Moreover, the proposed TDDDCP technique has the advantage over the Double Difference Carrier Phase (DDCP) because it requires data from only one satellite with two zero base length receivers for which the differential phase bias is to be measured. The experimental results show that the differential phase bias value differs for different satellites, ranging from −0.3904 m to 0.3168 m. The bias-free carrier phase observations based on position coordinates (X, Y, Z) found improved precision of standard deviation of 0.4176 m, 0.645 m, and 0.328 m, respectively.

The neglected Istanbul earthquakes in the North Anatolian Shear Zone: tectonic implications and broad-band ground motion simulations for a future moderate event

SUMMARYİstanbul (Marmara Region, NW Turkey) is one of the megacities in the world and suffered from destructive earthquakes on the North Anatolian Fault, a member of the North Anatolian Shear Zone, throughout history. The 1999 Kocaeli and Düzce earthquakes emphasize the earthquake potential of the fault, crossing the Sea of Marmara, and the importance of seismic hazards in the region. The studies in the last 20 yr have concentrated on the main fault and its future destructive earthquake potential. In this study, unlike the previous ones, we focus on the two main topics about the earthquakes not interested previously in İstanbul: (1) Investigating recent earthquake activity masked by the blasts in the metropolitan area and its tectonic implications, (2) revealing their effects in İstanbul utilizing numerical ground motion simulations for a future moderate event (Mw 5). First, the 386 earthquakes from 2006 to 2016 are relocated with the double-difference method using the dense seismic network operated in the same period. The source mechanisms of the events (ML ≥ 3), including the most recent 2021 Kartal–İstanbul earthquake (ML 4.1), are determined. In addition to the analysis of the recent seismic activity, the location of the two moderate and pre-instrumental-period İstanbul earthquakes, which occurred in 1923 (Mw 5.5) and 1929 (Mw 5.1), are revised. Using the relocated epicentres outside of the principal deformation zone and the fault plane solutions, the roles of the earthquakes in the stress regime of the Marmara region are explained. The epicentres on the Cenozoic or Palaeozoic formation in the Istanbul–Zonguldak Zone are interpreted as the re-activation of the palaeo-structures under the recent tectonic stresses, and their fault plane solutions agree with the synthetic/antithetic shears of a transtensional regime corresponding to the right lateral strike-slip system with mainly N–S extension in the Marmara Region. In the second part, we investigate the effects of moderate scenario events (Mw 5) considering the current earthquake epicentres in the İstanbul metropolitan area, using characterized earthquake source model and 1-D velocity structure verified with the broad-band (0.1–10 Hz) numerical ground motion simulation of the 2021 Kartal–İstanbul earthquake. The simulated PGAs agree with the ground-motion prediction equations for short epicentral distances (<30 km). Furthermore, according to the empirical relation for Turkish earthquakes, the maximum PGA value of the synthetic models (∼0.3 g) corresponds to the felt intensity of MMI IX. The simulated spectral accelerations for the Mw 5 earthquake scenarios may exceed the design spectrum between 0.2 and 0.6 s given in the Turkish Building Earthquake Code (2018). In addition, certain models also generate spectral accelerations close to the design-level spectrum between 0.4 and 1 s, leading to resonance phenomena. The results indicate that a moderate event (Mw 5) in the İstanbul metropolitan area is capable of damage potential for the mid-rise buildings (4–10 stories) because of the site condition with resonance phenomena and poor construction quality.

The impact of green urbanization on carbon emissions: The case of new urbanization in China

Urbanization in developing countries has brought economic growth and industrial development, but at the same time, it has also brought environmental problems, especially increased carbon emissions. Recently, China has promoted a new type of urbanization with the common goal of economic growth and green development, which provides a reference for the sustainable development of urbanization in developing countries. The study focuses on microscopic impact of this new urbanization on carbon emissions, which has received little attention previously. This study takes China as an example, constructs a quasi-natural experiment based on the first batch of new urbanization pilot areas in China, selects panel data of 164 prefecture-level cities from 2010–2019, applies the double difference method (DID) to identify the emission reduction effects of pilot policy on carbon emission (carbon emission intensity and per capita carbon emission), the mechanism of action model is constructed for further analysis, and various robustness tests are conducted. The results show that the new urbanization pilot policy can effectively diminish carbon emissions, and the sensitivity of pilot policy to per capita carbon emissions is greater than the intensity of carbon emissions, and the emission reduction effect of pilot policy of new urbanization tends to be enhanced with the implementation of pilot policy. With the improvement of infrastructure, the upgrading of advanced industrial structure, and the strengthening of environmental regulation, the inhibitory effect of new urbanization construction on carbon emissions tends to be enhanced. Various robustness tests show that green urbanization can effectively lessen carbon emissions, and under the constraint of economic growth rate target, if the government still gives priority to economic development, it is not conducive to the development of green urbanization. Therefore, the green urbanization process needs to be accelerated, infrastructure construction is linked, strict and appropriate environmental controls are adopted, the industrial layout is customized and the advanced industrial structure is promoted.

Impact of Fengyun-3E Microwave Temperature and Humidity Sounder Data on CMA Global Medium Range Weather Forecasts

In this study, the polarization characteristics of the newly launched Fengyun-3E (FY-3E) microwave sounding instruments are discussed, and its data quality is also assessed using one month of observation by the double-difference method. By comparison with the equivalent channels onboard Fengyun-3D (FY-3D) and advanced technology microwave sounder (ATMS), the data quality of FY-3E Microwave Humidity Sounder-II (MWHS-II) is improved and comparable to ATMS, while the data of FY-3E Microwave Temperature Sounder-III (MWTS-III) are slightly worse than data of FY-3D. The data of FY-3E MWTS-III are more susceptible to the early-morning orbit than the data of MWHS-II. In addition, striping noise is still present in channels 5–10 of MWTS-III. After the assessments, FY-3E microwave data are preprocessed and assimilated in the global forecast system for the Chinese Meteorology Administration (CMA-GFS). A total of six individual experiments over the period from 16 July to 15 August 2021 were conducted and the impact was evaluated with the composite score used in operation. It is shown that not only the forecasts for the southern hemisphere and tropics are improved significantly, but also the predictions for the northern hemisphere show some improvements in an overall neutral change from adding FY-3E microwave sounding instruments. The impact of FY-3E microwave radiance is equivalent to ATMS as they are assimilated individually. Furthermore, we note that the forecast impact is affected by the cloud detection scheme to a large extent.

Cleaner Production Standards and Increased Technical Complexity for Textile Exporters

An important prerequisite for promoting sustainable development and value chain climbing of textile enterprises is to achieve a win-win situation between environmental protection and export technical complexity. Thus, based on Chinese enterprises’ microdata, this paper investigates the impact of cleaner production standards implementation on the export technical complexity of Chinese textile enterprises using a double difference method. The results show that the implementation of cleaner production standards significantly increases the export technical complexity of Chinese textile enterprises. The results of the mechanism test indicate that cleaner production standards increase export technical complexity by enhancing capital and labor inputs of textile enterprises, as well as by promoting enterprise innovation and increasing productivity. Heterogeneity analysis shows that cleaner production standards have a significant role in increasing the export technical complexity of textile enterprises in the eastern region and larger scale; it is not significant in increasing the export technical complexity of textile enterprises in the central and western regions and smaller scale; in terms of enterprise ownership attributes, it has the greatest role in increasing the export technical complexity of state-owned textile enterprises, followed by foreign and private textile enterprises. The results of this paper show that cleaner production standards, as an environmental regulation policy, can achieve a win-win situation for environmental protection and export technical complexity increase.

The impact of the opening of the high-speed railway in the Silk Road economic belt on the regional economy based on the double difference method (PSM-DID)

Based on the perspective of the transportation economic belt, this paper studies the impact of the opening of the high-speed rail in the Silk Road Economic Belt on the regional economy. Taking the panel data of 74 cities in the five northwestern provinces and four southwestern provinces in the Silk Road Economic Belt from 2003 to 2018 as a sample, using propensity score matching and double difference method (PSM-DID) to conduct empirical research, the research found that: Firstly, in the urban agglomeration of the Silk Road Economic Belt, whether from the perspective of significance or robustness, the opening of high-speed rail has a significant positive impact on the regional economic effect, and there is a certain lag. Secondly, there is obvious heterogeneity in the impact of high-speed rail effect. In terms of city size, small and medium-sized cities are more affected by the opening of high-speed rail than large cities. From the administrative level, general cities are more susceptible to the opening of high-speed rail than key cities, and their economic development is better under the influence of high-speed rail effect. Thirdly, in terms of transmission mechanism, it is found that the opening of high-speed railway can promote urban economic development by improving the optimization of industrial structure, promoting labor mobility and reducing pollution emissions.

Impact of Environmental Protection Regulations on Corporate Performance From Porter Hypothesis Perspective: A Study Based on Publicly Listed Manufacturing Firms Data

“Porter Hypothesis” believes that environmental protection regulations contribute to cleaner production and green technology innovation which benefit to enhance manufacturing firm performance . We take China’s new “Environmental Protection Regulations (2015), as a quasi-natural experiment, using A-share listed companies in Shenzhen and Shanghai in 2012–2017 as a research sample. Using the propensity score matching and double difference (PSM-DID) method, we empirically test the impact of environmental regulations on the financial performance of these companies. The results show that the new Environmental Protection Law has significantly improved corporate profits of large enterprises large firms. Different from the innovation mechanism emphasized in the literature based on the Porter hypothesis, we find that “Compliance cost heterogeneity” caused by the scale difference of firms better explains the impact of environmental regulations on the profit margin of listed manufacturing firms. Overall, this study contributes novel insights about the economic consequences of environmental regulation and establishes an initial foundation for investigating environmental regulation from the perspective of compliance cost heterogeneity.

Research on the Mechanism of China’s Energy Saving and Emission Reduction Policy on Green Innovation in Enterprises

China’s extensive growth since reforming and opening its economy has led to increased pollution, and under the United Nations Framework Convention on Climate Change, Chinese companies must initiate green innovation to meet the world trend and enhance their international competitiveness. In addition, with institutional and cultural differences, policy drive is a key focus of China’s development. Therefore, China’s Energy Saving and Emission Reduction policy has its own necessity and characteristics as a mechanism for green innovation in enterprises. This study examines the impact of the 13th Five-Year Plan on green innovation from the perspective of the Energy Saving and Emission Reduction policy. First, the data of 100 listed enterprises in two control zones (TCZ) and non-two-control zones (non-TCZ) from 2014 to 2019 were selected to identify whether the implementation of the policy has an impact on the innovation of heavily polluting enterprises using the double-difference method (DID). The study found that the 13th Five-Year Plan for Energy Saving and Emission Reduction had a negative impact on the innovation of heavily polluting enterprises. Further, the study found that the policy had a negative impact on enterprises’ innovation through the transmission channel of increasing the environmental cost of enterprises, thus reducing investment in research and development (R&D). It is suggested that the state should start with the policy itself, identify its precise target, and formulate flexible environmental regulation policies.

The Kalaotoa Fault: A Newly Identified Fault that Generated the Mw 7.3 Flores Sea Earthquake

AbstractWe reveal the existence of a previously unknown fault that generated the Mw 7.3 Flores Sea earthquake, which occurred on 14 December 2021, approximately 100 km to the north of Flores Island, in one of the most complex tectonic settings in Indonesia. We use a double-difference method to relocate the hypocenters of the mainshock and aftershocks, determine focal mechanisms using waveform inversion, and then analyze stress changes to estimate the fault type and stress transfer. Our relocated hypocenters show that this earthquake sequence ruptured on at least three segments: the source mechanism of the mainshock exhibits dextral strike-slip motion (strike N72°W and dip 78° NE) on a west–east-trending fault that we call the Kalaotoa fault, whereas rupture of the other two segments located to the west and east of the mainshock (striking west-northwest and southeast, respectively) may have been triggered by this earthquake. The Coulomb stress change imparted by the rupture of these segments on nearby faults is investigated, with a focus on regions that experience a stress increase with few associated aftershocks. Of particular interest are stress increases on the central back-arc thrust just north of Flores and the north–south-striking Selayar fault in the northwest of our study region, both of which may be at increased risk of failure as a result of this unusual earthquake sequence.

Outer trench slope extension to frontal wedge compression in a subducting plate

The occurrence of faulting in subducting plates is a major process that changes the mechanical properties of the subducting lithosphere and carries surface materials into mantle wedges. Two ocean-bottom seismometer networks deployed on the frontal accretionary wedge of the northern Manila trench in 2005 and on the outer slope of the trench in 2006 were used to detect earthquakes in the subducting plate. All available P and S manually picked phases and the waveforms of 16 short-period, three-component stations were used. Relocation was performed using the double-difference method with differential times derived from the phase-picked data. Two intraplate earthquake sequences of small-to-moderate magnitudes in the northern Manila subduction system were investigated in this study. The results revealed distinct fault planes, but a contrasting seismogeny over the northern Manila Trench. The seismicity in the frontal wedge (as measured in 2005) was mainly contributed by a fluid overpressure sequence, whereas that in the incoming plate (as measured in 2006) was contributed by the aftershocks of an extensional faulting sequence. The obtained seismic velocity models and Vp/Vs ratios revealed that the overpressure was likely caused by high pore-fluid pressure within the shallow subduction zone. By using the near-field waveform inversion algorithm, we determined focal mechanism solutions for a few relatively large earthquakes. Through the use of data obtained from global seismic observations, we determined that stress transfer may be responsible for the seismic activity in the study area during the period of 2005–2006. In late 2005, the plate interface in the frontal wedge area was unlocked by the overpressure effect due to a thrusting-dominant sequence. This event changed the stress regime across the Manila Trench and triggered a normal fault extension at the outer trench slope in mid-2006. However, in the present study, a hybrid focal mechanism solution indicating reverse and strike–slip mechanisms was implemented, and it revealed that the plate interface locked again in late 2006.Graphical

Impact mechanism of carbon emission trading pilot policy on green total factor productivity——Empirical research based on the double difference model

This paper uses the panel data of 30 provinces and cities in China from 2008 to 2018, adopts the double-difference method and the mediation effect model to empirically evaluate the carbon emission reduction effect of the carbon emission trading pilot policy, and demonstrates that the specific impact mechanism of carbon emission trading pilot policy to improve green total factor productivity The study found that the carbon emission trading pilot policy promotes carbon emission reduction in regional industries through cost-benefit mechanisms, market mechanisms, and technological innovation mechanisms, thereby improving green total factor productivity; Corporate green technology innovation is the key way to promote carbon emission reduction and low-carbon development. , and the introduction of high-quality human capital can enhance the concept of green development for enterprises; the role of financial products such as green credit and green finance in serving green development has yet to be explored, and the foreign investment in the field of green development needs to be guided. Finally, it is concluded that the implementation of the pilot policy should uphold the principle of combining the government's macro-control and market-determining mechanism, play the key role of technological innovation, and formulate differentiated policies.

Research on the Influence of FTZ Policy on Regional Economy

China's free trade zone has achieved relatively mature development, showing a trend of extending from the east to the West. Current studies generally believe that the early establishment of the free trade zone will have a positive impact on the near area, so what about the establishment of the third inland free trade zone? In order to study its economic impact, this paper uses DID method to select the annual panel data of Chinese provinces, cities and autonomous regions from 2006 to 2018, from economic growth, foreign trade and freight volume, etc. This paper evaluates the economic effects of three free trade zones in the middle and upper reaches of the Yangtze River, namely, Sichuan, Chongqing and Hubei. According to the functional orientation of the three FTZ, the mechanism of the three FTZ is analyzed qualitatively. In terms of quantitative research, this paper uses the double difference method to analyze the differences in economy, trade and freight volume after the establishment of the free trade zone by analyzing the coefficients of policy variables and their significance. A robustness test was carried out on the impact of the post-policy implementation on the regional economy and foreign trade, and it was concluded that the three provinces had a positive impact on the regional economy and trade. Finally, relevant development suggestions are put forward.

Can Network Infrastructure Construction Alleviate Corporate Financing Constraints?

T The construction of network infrastructure is conducive to promoting enterprises to ease financing constraints, which is of great practical significance for optimizing the allocation efficiency of enterprise factors and promoting high-quality economic development. Based on the perspective of information asymmetry, taking the "Broadband China" pilot as a natural experiment, using the data of Chinese listed companies from 2009 to 2020, and using the multi-period double difference method to empirically test the impact of network infrastructure construction on the constraint level of enterprise financing and verify its internal mechanism. The study found that the construction of network infrastructure helps to alleviate the financing constraint level of enterprises. Heterogeneity analysis shows that the policy significantly alleviates the financing constraints of large-scale enterprises, but the impact on small and medium-sized enterprises is not significant. The conclusions of this paper not only broaden the perspective of "new infrastructure" research, but also provide reliable empirical evidence and policy implications for the impact of network infrastructure construction on micro-enterprise behavior.

The impact of capital market opening on China's stock liquidity

Taking the listed companies in Shanghai stock market from 2011 to 2017 and the listed companies in Shenzhen stock market from 2013 to 2019 as samples, this paper uses the ratio of the absolute value of daily return to the daily turnover to measure the stock liquidity, and uses the double difference method to test whether the capital market opening has a significant impact on the liquidity of China's stock market. The results show that the opening of the capital market is conducive to improving the liquidity of the stock market, and the effect of Shenzhen stock market is more obvious.