As of January 31,2024,China had concluded mutual visa exemption agreements covering different types of passports with 157 countries,reached agreements or arrangements on simplified visa procedures with 44 countries,an...As of January 31,2024,China had concluded mutual visa exemption agreements covering different types of passports with 157 countries,reached agreements or arrangements on simplified visa procedures with 44 countries,and enjoyed comprehensive mutual visa exemptions with 23 countries including Thailand,Singapore,Maldives,and the United Arab Emirates.展开更多
In recent yea rs,t raditiona l offline supermarkets are facing big challenges,and warehouse membership superma rkets(hereinafter referred to as membership supermarkets)are quickly gaining p opu l a r it y.Ma ny t r ad...In recent yea rs,t raditiona l offline supermarkets are facing big challenges,and warehouse membership superma rkets(hereinafter referred to as membership supermarkets)are quickly gaining p opu l a r it y.Ma ny t r ad it iona l supermarkets have become membership supermarkets,and even many retail enterprises have entered this field.展开更多
CHINA’S visa-free policy keeps expanding and the country has entered a new era of welcoming visitors from an increasing global reach.By January 1,2024,China had inked mutual visa exemption agreements with 157 countri...CHINA’S visa-free policy keeps expanding and the country has entered a new era of welcoming visitors from an increasing global reach.By January 1,2024,China had inked mutual visa exemption agreements with 157 countries,simplified visa procedures with 44 countries,and enjoyed comprehensive mutual visa exemptions with 23 countries,including Thailand,Singapore,the Maldives,and the United Arab Emirates.展开更多
AIM To measure the willingness to pay for colorectal cancer screening in Guangzhou, and to identify those factors associated with it. METHODS A face-to-face questionnaire survey for pre-screening population from free ...AIM To measure the willingness to pay for colorectal cancer screening in Guangzhou, and to identify those factors associated with it. METHODS A face-to-face questionnaire survey for pre-screening population from free and non-free colonoscopy districts was used to collect information on demographic characteristics, health behaviours, the intention of the cancer screenings and willingness to pay for colorectal cancer screening. A total of 1243 participants who took part in the pre-screening for colorectal cancer in Guangzhou were collected in the study. Categorical data were compared using the χ~2 test to analyse significant differences. Non-conditional logistic regression and multi-class logistic regression were also performed for multivariate analysis and to estimate the odds ratios.RESULTS The percentage of participants willing to pay for colorectal cancer screening was 91.7%. "Unnecessary" was the dominant reason that participants gave for their unwillingness, accounting for 63.1%. Of those who were willing to pay, 29.2%, 20.7%, 14.8%, 13.0% and 22.4% of participants were willing to pay less than $100, $100-$199, $200-299, $300-$399 and more than $400, respectively. Non-logistic regression analysis showed that respondents who were male, had a high level of education, were from the family with more children/older to raise, and accepted colorectal cancer screening were willing to pay for this screening. Multi-class logistic regression analysis showed that respondents with higher annual household income per capita, from government and private enterprises, government agency/institution and peasants, and less family medical expenditure were willing to pay more.CONCLUSION Willingness to pay for colorectal cancer screening in Guangzhou is high, but the amount of willing to pay is not much.展开更多
Along with the progress of urbanization and environ- mental deterioration, residents’ desire for improved air quality is increasing. In order to quantify an individual’s willingness-to-pay (WTP) for improved air qua...Along with the progress of urbanization and environ- mental deterioration, residents’ desire for improved air quality is increasing. In order to quantify an individual’s willingness-to-pay (WTP) for improved air quality in Jinan of eastern China, a contingent valuation method (CVM) was employed. A sample of 1,500 residents was chosen on the basis of multistage sampling methods with face-to-face interviews by using a series of hypo-thetical, open-ended scenario questions which were designed to elicit the respondents’ WTP. Results showed that 59.7% of respondents were able to express their WTP and the mean WTP is 100 Chinese Yuan (CNY) per person per year. A probit model on the probability of a positive WTP and a regression model were developed to find the relationship between endogenous variables and WTP. Most parameters in the econometric analysis had the expected sign. Annual household income and expenditure on treating respiratory diseases significantly influence WTP. The rates of positive WTP and the monetary amount are larger for men than for women. Results also showed that people who lived in more polluted areas were willing to pay more for clean air. Unlike developed countries, clean air may only be considered as a public good in China in that more than 40% of respondents had no incen- tive to bear the costs of attempting to achieve better air quality, which indicates the relatively low environmental consciousness.展开更多
This paper presents an overview of petrophysical research and exploration achievements of low resistivity pay (LRP) zone by well logs in China. It includes geological characteristics and characteristics of well log ...This paper presents an overview of petrophysical research and exploration achievements of low resistivity pay (LRP) zone by well logs in China. It includes geological characteristics and characteristics of well log response of the low resistivity pay zones discovered and evaluated in recent years, as well as the problems in recognizing and evaluating low resistivity pay zones by well logs. The research areas mainly include the Neogene formations in the Bohai Bay Basin, the Triassic formations in the northern Tarim Basin and the Cretaceous formations in the Junggar Basin, The petrophysical research concerning recognition and evaluation of the low resistivity pays, based on their genetic types, is introduced in this paper.展开更多
In the early exploration of many oilfields,low-resistivity-low-contrast(LRLC)pay zones are easily overlooked due to the resistivity similarity to the water zones.Existing identification methods are model-driven and ca...In the early exploration of many oilfields,low-resistivity-low-contrast(LRLC)pay zones are easily overlooked due to the resistivity similarity to the water zones.Existing identification methods are model-driven and cannot yield satisfactory results when the causes of LRLC pay zones are complicated.In this study,after analyzing a large number of core samples,main causes of LRLC pay zones in the study area are discerned,which include complex distribution of formation water salinity,high irreducible water saturation due to micropores,and high shale volume.Moreover,different oil testing layers may have different causes of LRLC pay zones.As a result,in addition to the well log data of oil testing layers,well log data of adjacent shale layers are also added to the original dataset as reference data.The densitybased spatial clustering algorithm with noise(DBSCAN)is used to cluster the original dataset into 49 clusters.A new dataset is ultimately projected into a feature space with 49 dimensions.The new dataset and oil testing results are respectively treated as input and output to train the multi-layer perceptron(MLP).A total of 3192 samples are used for stratified 8-fold cross-validation,and the accuracy of the MLP is found to be 85.53%.展开更多
Contingent Valuation Method(CVM) was used to investigate the Chinese public's willingness to pay(WTP) for a policy to reduce CO2 emissions. Face to face interviews were conducted to collect 1,653 valid questionnai...Contingent Valuation Method(CVM) was used to investigate the Chinese public's willingness to pay(WTP) for a policy to reduce CO2 emissions. Face to face interviews were conducted to collect 1,653 valid questionnaires from Beijing, Shanghai, Shandong province, and Fujian province. A model was constructed to understand the factors that influence WTP. The results indicate that the Chinese public is willing to pay CN 201.86 annually to support the policy of reducing greenhouse gas emissions. Participants from Beijing show the highest WTP, followed by participants from Fujian and Shandong, while those from Shanghai report the lowest WTP. The findings reveal that participants with higher income, higher satisfaction with their current life, and awareness of climate issues are willing to pay more for CO2 emissions reductions. In addition, those who are young, male and members of the Communist Party also indicate a higher WTP. The results imply that translating the public's willingness to protect climate into actions should be taken into account in China's low carbon policy. There is a need to consider the difference in degree of willingness, among different social groups, to pay for emissions reductions if the market-based mechanisms such as carbon tax were designed to facilitate emissions reductions.展开更多
文摘As of January 31,2024,China had concluded mutual visa exemption agreements covering different types of passports with 157 countries,reached agreements or arrangements on simplified visa procedures with 44 countries,and enjoyed comprehensive mutual visa exemptions with 23 countries including Thailand,Singapore,Maldives,and the United Arab Emirates.
文摘In recent yea rs,t raditiona l offline supermarkets are facing big challenges,and warehouse membership superma rkets(hereinafter referred to as membership supermarkets)are quickly gaining p opu l a r it y.Ma ny t r ad it iona l supermarkets have become membership supermarkets,and even many retail enterprises have entered this field.
文摘CHINA’S visa-free policy keeps expanding and the country has entered a new era of welcoming visitors from an increasing global reach.By January 1,2024,China had inked mutual visa exemption agreements with 157 countries,simplified visa procedures with 44 countries,and enjoyed comprehensive mutual visa exemptions with 23 countries,including Thailand,Singapore,the Maldives,and the United Arab Emirates.
基金Supported by the Natural Science Foundation of Guangdong Province,No.2016A030313504Guangzhou Science and Technology Program Key Project,No.201707010205
文摘AIM To measure the willingness to pay for colorectal cancer screening in Guangzhou, and to identify those factors associated with it. METHODS A face-to-face questionnaire survey for pre-screening population from free and non-free colonoscopy districts was used to collect information on demographic characteristics, health behaviours, the intention of the cancer screenings and willingness to pay for colorectal cancer screening. A total of 1243 participants who took part in the pre-screening for colorectal cancer in Guangzhou were collected in the study. Categorical data were compared using the χ~2 test to analyse significant differences. Non-conditional logistic regression and multi-class logistic regression were also performed for multivariate analysis and to estimate the odds ratios.RESULTS The percentage of participants willing to pay for colorectal cancer screening was 91.7%. "Unnecessary" was the dominant reason that participants gave for their unwillingness, accounting for 63.1%. Of those who were willing to pay, 29.2%, 20.7%, 14.8%, 13.0% and 22.4% of participants were willing to pay less than $100, $100-$199, $200-299, $300-$399 and more than $400, respectively. Non-logistic regression analysis showed that respondents who were male, had a high level of education, were from the family with more children/older to raise, and accepted colorectal cancer screening were willing to pay for this screening. Multi-class logistic regression analysis showed that respondents with higher annual household income per capita, from government and private enterprises, government agency/institution and peasants, and less family medical expenditure were willing to pay more.CONCLUSION Willingness to pay for colorectal cancer screening in Guangzhou is high, but the amount of willing to pay is not much.
基金The Natural Science Foundation of Shandong Prov-ince (Grant No. Y2005E01)The Environment Protection Science and Technology Project of Shandong Province (No. [2006] 025).
文摘Along with the progress of urbanization and environ- mental deterioration, residents’ desire for improved air quality is increasing. In order to quantify an individual’s willingness-to-pay (WTP) for improved air quality in Jinan of eastern China, a contingent valuation method (CVM) was employed. A sample of 1,500 residents was chosen on the basis of multistage sampling methods with face-to-face interviews by using a series of hypo-thetical, open-ended scenario questions which were designed to elicit the respondents’ WTP. Results showed that 59.7% of respondents were able to express their WTP and the mean WTP is 100 Chinese Yuan (CNY) per person per year. A probit model on the probability of a positive WTP and a regression model were developed to find the relationship between endogenous variables and WTP. Most parameters in the econometric analysis had the expected sign. Annual household income and expenditure on treating respiratory diseases significantly influence WTP. The rates of positive WTP and the monetary amount are larger for men than for women. Results also showed that people who lived in more polluted areas were willing to pay more for clean air. Unlike developed countries, clean air may only be considered as a public good in China in that more than 40% of respondents had no incen- tive to bear the costs of attempting to achieve better air quality, which indicates the relatively low environmental consciousness.
基金Supported by CNPC Innovation Foundation,Research Projects of PetroChina,Xinjiang and Tarim Oil Companies
文摘This paper presents an overview of petrophysical research and exploration achievements of low resistivity pay (LRP) zone by well logs in China. It includes geological characteristics and characteristics of well log response of the low resistivity pay zones discovered and evaluated in recent years, as well as the problems in recognizing and evaluating low resistivity pay zones by well logs. The research areas mainly include the Neogene formations in the Bohai Bay Basin, the Triassic formations in the northern Tarim Basin and the Cretaceous formations in the Junggar Basin, The petrophysical research concerning recognition and evaluation of the low resistivity pays, based on their genetic types, is introduced in this paper.
基金funded by the Strategic Cooperation Technology Projects of CNPC and CUPB(ZLZX2020-03)
文摘In the early exploration of many oilfields,low-resistivity-low-contrast(LRLC)pay zones are easily overlooked due to the resistivity similarity to the water zones.Existing identification methods are model-driven and cannot yield satisfactory results when the causes of LRLC pay zones are complicated.In this study,after analyzing a large number of core samples,main causes of LRLC pay zones in the study area are discerned,which include complex distribution of formation water salinity,high irreducible water saturation due to micropores,and high shale volume.Moreover,different oil testing layers may have different causes of LRLC pay zones.As a result,in addition to the well log data of oil testing layers,well log data of adjacent shale layers are also added to the original dataset as reference data.The densitybased spatial clustering algorithm with noise(DBSCAN)is used to cluster the original dataset into 49 clusters.A new dataset is ultimately projected into a feature space with 49 dimensions.The new dataset and oil testing results are respectively treated as input and output to train the multi-layer perceptron(MLP).A total of 3192 samples are used for stratified 8-fold cross-validation,and the accuracy of the MLP is found to be 85.53%.
基金supported by the Foundation of the Humanities and Social Science, Ministry of Education of the People’s Republic of China (No. 09YJA790119)
文摘Contingent Valuation Method(CVM) was used to investigate the Chinese public's willingness to pay(WTP) for a policy to reduce CO2 emissions. Face to face interviews were conducted to collect 1,653 valid questionnaires from Beijing, Shanghai, Shandong province, and Fujian province. A model was constructed to understand the factors that influence WTP. The results indicate that the Chinese public is willing to pay CN 201.86 annually to support the policy of reducing greenhouse gas emissions. Participants from Beijing show the highest WTP, followed by participants from Fujian and Shandong, while those from Shanghai report the lowest WTP. The findings reveal that participants with higher income, higher satisfaction with their current life, and awareness of climate issues are willing to pay more for CO2 emissions reductions. In addition, those who are young, male and members of the Communist Party also indicate a higher WTP. The results imply that translating the public's willingness to protect climate into actions should be taken into account in China's low carbon policy. There is a need to consider the difference in degree of willingness, among different social groups, to pay for emissions reductions if the market-based mechanisms such as carbon tax were designed to facilitate emissions reductions.