US Presidential Election Reflects Major Changes in US PoliticsAt present,there have been quite a few assessments on the historical significance of US Presidential Election2016 for political change in the United States...US Presidential Election Reflects Major Changes in US PoliticsAt present,there have been quite a few assessments on the historical significance of US Presidential Election2016 for political change in the United States,all of which be it high or low point to a new departure point or turning point in US politics.First,the Election reflects major changes in the power pattern展开更多
Happy New Year!As we step into a new year,we take a look back at the key feature topics covered in China Communications over the past 12 months and set out our expecta-
Today, more than 2,000 astronomers from all over the world gather together in Beijing to attend the 28^th General Assembly of the International Astronomical Union （IAU）. This is a grand event for astronomy. It is th...Today, more than 2,000 astronomers from all over the world gather together in Beijing to attend the 28^th General Assembly of the International Astronomical Union （IAU）. This is a grand event for astronomy. It is the first time for China to host an IAU General Assembly since China joined the IAU in 1935. On behalf of President HU Jintao, the Chinese Government, and the Chinese people, I am here to express our warm congratulations to this General Assembly, and express our sincere gratitude and cordial welcome to all attendants.展开更多
At all times and in all countries of the world, people have been fascinated by obtaining deeper insights into life and have eagerly absorbed new knowledge from around the globe. Thus in addition to trade, the sciences...At all times and in all countries of the world, people have been fascinated by obtaining deeper insights into life and have eagerly absorbed new knowledge from around the globe. Thus in addition to trade, the sciences early on became one of the most fruitful areas of worldwide exchange and international communication. Today, it is still often the sciences that bridge national and cultural differences between countries. The Chinese Academy of Sciences and the Max Planck Society can proudly look back展开更多
For centuries, the continuous development of science and technology has greatly promoted the process of mankind's understanding and utilization of nature, and at the same time strongly enhanced exchanges and coope...For centuries, the continuous development of science and technology has greatly promoted the process of mankind's understanding and utilization of nature, and at the same time strongly enhanced exchanges and cooperation between various nationalities and different civilizations. In the modern era, science and technology are developing vigorously and changing with each passing day. Strengthening international scientific cooperation is invaluable in展开更多
The 14^th General Meeting of TWAS was held in Beijing nine years ago. Today, we are celebrating the 23^rd General Meeting of TWAS here in Tianjin, which is indeed a grand gathering of the international scientific comm...The 14^th General Meeting of TWAS was held in Beijing nine years ago. Today, we are celebrating the 23^rd General Meeting of TWAS here in Tianjin, which is indeed a grand gathering of the international scientific community. First of all, on behalf of the Chinese people and government, I would like to extend our hearty congratulations on the convening of this meeting and our warm welcome to all TWAS Fellows, scientists and delegates from around the world.展开更多
PCIM China, international conference and exhibition for power electronics, was held in Shanghai on March 21, 2006. PCIM is one of the most authoritative organizations and has won good reputation overseas for a long time.
It is with great interest that I read the book Up and Out of Poverty,written by Chinese President Xi Jinping.The book was originally published in 2016,but remains highly topical today.Besides the struggle against pove...It is with great interest that I read the book Up and Out of Poverty,written by Chinese President Xi Jinping.The book was originally published in 2016,but remains highly topical today.Besides the struggle against poverty,which,in itself,is an essential issue of governance in modern times,President Xi addresses various other important issues in the book,including the relations and links between cadres and local people,pursuit of excellence in work,quality of state administration,industrial policies,education,cul tural construction,ethical rules in governance,etc.展开更多
24 China Textile Top Interview Swiss Textile Machinery: Many of the innovations will integrate digitalisation and sustainability Interview with Mr. Ernesto Maurer, President of Swissmem, Swiss Textile Machinery Associ...24 China Textile Top Interview Swiss Textile Machinery: Many of the innovations will integrate digitalisation and sustainability Interview with Mr. Ernesto Maurer, President of Swissmem, Swiss Textile Machinery Association ITMA 2019 will demonstrate the “inventive DNA” of Switzerland’s machinery producers. Swissmem is keen to emphasise the spirit of inventiveness which has brought history-making breakthroughs as diverse as the chocolate bar, fizzy drinks and the computer mouse – as well as a continuing stream of textile-related innovations for which ITMA will provide the latest evidence.展开更多
2004 was a year of continuous progression and development along the reform of Chinese electric industry, and a year of facing great challenge and opportunity of development, in this unordinary year, guided by the conc...2004 was a year of continuous progression and development along the reform of Chinese electric industry, and a year of facing great challenge and opportunity of development, in this unordinary year, guided by the concept of scientific development, the electric power sectors grasped the nettle, made progress volitionally, held together on teamwork, and pushed forward all-round, coordinated and sustainable development of the power industry.展开更多
Over the next 20 years,China's urban rail transit(hereinafter referred to as'urban rail')will face large-scalerenovation of existing line facilities and equipment,with more than 1000 km of renovated lines ...Over the next 20 years,China's urban rail transit(hereinafter referred to as'urban rail')will face large-scalerenovation of existing line facilities and equipment,with more than 1000 km of renovated lines to be added eachyear.In 2024,the China Association of Metros issued the Guiding Opinions on the Renovation of Existing UrbanRail Transit Lines in China,providing guiding opinions on norms,standards,and implementation approaches forthe renovation of existing lines in the coming period.In the practical work of renovating existing urban rail lines,it is necessary to continuously explore and refine relevant theoretical methods in line with industry developmenttrends and urban development requirements.The following are the author's recent reflections on theoreticalinnovation in this field.展开更多
It is normal for an association to issue publications,for they serve as the means for communication among members,as well as between members and the association.Certainly,publications may range from a few pages of a n...It is normal for an association to issue publications,for they serve as the means for communication among members,as well as between members and the association.Certainly,publications may range from a few pages of a newsletter to some kind of bulletin or magazine with lots of news concerning the subjects of interest.The most desired form of publication that an association would like to do,though not always realized,is a scientific journal.However,to publish a journal is not a simple matter;many factors that point to the success or failure of such an enterprise abound.展开更多
The past 2 years we now have behind us have demonstrated the importance of understanding the dynamics of zoonotic diseases in the wild and how the disease agents spill over to the human population.At the end of 2021,I...The past 2 years we now have behind us have demonstrated the importance of understanding the dynamics of zoonotic diseases in the wild and how the disease agents spill over to the human population.At the end of 2021,Integrative Zoology published 2 special subsections on this topic,one of which focuses on plague—a zoonotic infectious disease which through history has ravaged the world.Plague,caused by the bacterium Yersinia pestis,continues to cause deaths among people.I am quite confident that we will not get rid of wildlife plague,but human plague epidemics might be history in the not too distant future(Baril et al.2019;Vallès et al.2020).展开更多
Objectives This study aimed to develop and preliminarily assess the quality of a Mindfulness Breast Care(MBC)App to reduce body image distress and stigma among breast cancer survivors(BCSs).Methods The development pro...Objectives This study aimed to develop and preliminarily assess the quality of a Mindfulness Breast Care(MBC)App to reduce body image distress and stigma among breast cancer survivors(BCSs).Methods The development process of the MBC App involved:1)establishing a research group;2)determining of the content of the MBC App based on Mindfulness-Based Cognitive Therapy and 3)technical exploitation and maintenance.A mixed-methods study was conducted.We selected ten BCSs by a convenience sampling method.After using the APP for three months,five assessed the quality using the Mobile App Rating Scale:User Version(uMARS)and another five were interviewed for process evaluation.Results The MBC App was developed with three modules:1)Library to provide health education information on body image,stigma,mindfulness,recovery and etc;2)Mindfulness Yoga to offer 12 Hatha yoga videos for daily practice;and 3)Mindfulness Practices to have 12 sessions of mindfulness videoconferences.Based on the uMARS data,the MBC App received high ratings for functionality(4.10±0.34),aesthetics(3.93±0.55),information quality(4.10±0.72),and perceived impact(4.03±0.96),as well as moderate ratings for engagement(3.72±0.94)and subjective quality(3.87±0.77).Participants indicated that the MBC App provided reliable knowledge,information,and emotional support.Recommendations from participants included categorizing knowledge in the Library Module,recording videoconferences of mindfulness practice,and adding discussion sessions in the videoconference.Afterward,we optimized the MBC App to enhance the user experience accordingly.Conclusions The MBC App offers online mindfulness interventions specifically for BCSs in China.The preliminary quality assessment indicates that the MBC App may be a promising tool for delivering mindfulness interventions to BCSs.展开更多
Here we compare the efficacy of anti-obesity drugs alone or combined with exercise training on body weight and exercise capacity of obese patients.Randomized clinical trials that assessed the impact of any anti-obesit...Here we compare the efficacy of anti-obesity drugs alone or combined with exercise training on body weight and exercise capacity of obese patients.Randomized clinical trials that assessed the impact of any anti-obesity drug alone or combined with exercise training on body weight,body fat,fat-free mass and cardiorespiratory fitness in obese patients were retrieved from Pubmed and EMBASE up to May 2024.Risk of bias assessment was performed with RoB 2.0,and the GRADE approach assessed the certainty of evidence(CoE)of each main outcome.We included four publications summing up 202 patients.Two publications used orlistat as an anti-obesity drug treatment,while the other two adopted GLP-1 receptor agonist(liraglutide or tirzepatide)as a pharmacotherapy for weight management.Orlistat combined with exercise was superior to change body weight(mean difference(MD):−2.27 kg;95%CI:−2.86 to−1.69;CoE:very low),fat mass(MD:−2.89;95%CI:−3.87 to−1.91;CoE:very low),fat-free mass(MD:0.56;95%CI:0.40–0.72;CoE:very low),and VO_(2)Peak(MD:2.64;95%CI:2.52–2.76;CoE:very low).GLP-1 receptor agonist drugs combined with exercise had a great effect on body weight(MD:−3.96 kg;95%CI:−5.07 to−2.85;CoE:low),fat mass(MD:−1.76;95%CI:−2.24 to−1.27;CoE:low),fat-free mass(MD:0.50;95%CI:−0.98 to 1.98;CoE:very low)and VO_(2)Peak(MD:2.47;95%CI:1.31–3.63;CoE:very low).The results reported here suggest that exercise training remains an important approach in weight management when combined with pharmacological treatment.展开更多
Improving the specific,technical,economic,and environmental characteristics of piston engines(ICE)operating on alternative gaseous fuels is a pressing task for the energy and mechanical engineering industries.The aim ...Improving the specific,technical,economic,and environmental characteristics of piston engines(ICE)operating on alternative gaseous fuels is a pressing task for the energy and mechanical engineering industries.The aim of the study was to optimize the parameters of the ICE working cycle after replacing the base fuel(propane-butane blend)with syngas from wood sawdust to improve its technical and economic performance based on mathematical modeling.The modeling results were verified through experimental studies(differences for key parameters did not exceed 4.0%).The object of the study was an electric generator based on a single-cylinder spark ignition engine with a power of 1 kW.The article describes the main approaches to creating a mathematical model of the engine working cycle,a test bench for modeling verification,physicochemical properties of the base fuel(propane-butane blend),and laboratory syngas.It was shown that replacing the fuel from a propane-butane blend to laboratory syngas caused a decrease in engine efficiency to 33%(the efficiency of the base ICE was 0.179 vs.the efficiency of 0.119 for the converted ICE for the 0.59 kW power mode).Engine efficiency was chosen as the key criterion for optimizing the working cycle.As a result of optimization,the efficiency of the converted syngas engine was 6.1%higher than that of the base engine running on the propane-butane blend,and the power drop did not exceed 8.0%.Thus,careful fine-tuning of the working cycle parameters allows increasing the technical and economic characteristics of the syngas engine to the level of ICEs running on traditional types of fuel.展开更多
Industry and energy continue to require piston engines(PICE)at a high level worldwide.Therefore,science and technology must urgently work on improving the PICE working cycle.Improving the quality of the intake process...Industry and energy continue to require piston engines(PICE)at a high level worldwide.Therefore,science and technology must urgently work on improving the PICE working cycle.Improving the quality of the intake process of theworking fluid into the cylinder is one of the most effective ways to improve the operational performance of PICE.The purpose of the study was to assess the impact of various cylinder head(CylH)designs on the gas-dynamic and heat-exchange qualities of air flows within an engine model’s intake system.Three different CylH designs were studied:the basic configuration and upgraded cylinder heads with a square valve and a square valve port.These designs are innovative.Laboratory conditions were used to conduct the studies for stationary air flow.The experiments covered the range of Reynolds numbers from 8500 to 96,000.The intake system’s gas dynamics and heat transfer were determined using the thermal anemometry method,which was based on constant-temperature hot-wire anemometers.It has been established that the use of upgraded CylHs causes an increase in the turbulence number of flow by an average of 13.5%.Additionally,itwas found that the increase in the turbulence number of flowin the cylinder is about 19%when installing new CylH designs.It was shown that therewas an increase in the heat transfer coefficient in the intake pipe by 10%–40%when installing modernized CylH designs in the intake system.The article focused on the problems of increasing the turbulence level and intensifying the heat transfer of stationary air flow in the intake system,specifically in PICEs.The study’s findings are novel in the areas of applied gas dynamics and PICEs.展开更多
We find the necessary and sufficient conditions on a coproduct of connected acts over a semigroup to be strongly hopfian. From this, we deduce the conditions of the strong hopfness for unitary acts over groups. Moreov...We find the necessary and sufficient conditions on a coproduct of connected acts over a semigroup to be strongly hopfian. From this, we deduce the conditions of the strong hopfness for unitary acts over groups. Moreover, we prove that a finite coproduct of strongly hopfian acts over an arbitrary semigroup is strongly hopfian.展开更多
Mongolia is a landlocked country with limited infrastructure and high dependence on the Xingang Tianjin port in China for imports. This research examines the potential impacts of establishing a dry port in Zamyn-Uud, ...Mongolia is a landlocked country with limited infrastructure and high dependence on the Xingang Tianjin port in China for imports. This research examines the potential impacts of establishing a dry port in Zamyn-Uud, Mongolia, utilizing a system dynamics modeling approach via Vensim software. The study evaluates transportation time, costs, inflation, and logistics performance index improvements, revealing that the establishment of the dry port can reduce transportation costs and delays significantly while enhancing economic growth. The findings offer actionable insights for policymakers and stakeholders in addressing logistical inefficiencies and fostering sustainable development in landlocked regions.展开更多
As a major principle underlying the Communist Party of China's(CPC)governance in the new era and a core piece of its holistic approach to national security,ensuring both development and security emphasizes compreh...As a major principle underlying the Communist Party of China's(CPC)governance in the new era and a core piece of its holistic approach to national security,ensuring both development and security emphasizes comprehensive governance from a long-term perspective and influences the world with its global vision.It keeps pace with the times by prioritizing innovative areas and is of great theoretical and practical significance.On the new journey ahead,we must firmly ensure both development and security.More importantly,we must ensure both high-quality development and high-level security,safeguarding the former through the latter.This is an urgent requirement we face in today's world,which has entered a period of turbulence and transformation characterized by increasing complexity.Confronted with the formidable tasks of promoting reform and development while maintaining stability at home and the grave challenges brought about by international turbulence and changes,we must earnestly implement the guiding principles of the 20th CPC National Congress and the third plenary session of the 20th Party Central Committee.We should ensure secure and sustainable development,accelerate efforts to modernize China's national security system and capacity,foster high-level security,and improve the mechanisms for preserving national security in foreign-related affairs.In short,we should strive to achieve a positive interplay between high-quality development and high-level security,so as to effectively safeguard Chinese modernization.展开更多
文摘US Presidential Election Reflects Major Changes in US PoliticsAt present,there have been quite a few assessments on the historical significance of US Presidential Election2016 for political change in the United States,all of which be it high or low point to a new departure point or turning point in US politics.First,the Election reflects major changes in the power pattern
文摘Happy New Year!As we step into a new year,we take a look back at the key feature topics covered in China Communications over the past 12 months and set out our expecta-
文摘Today, more than 2,000 astronomers from all over the world gather together in Beijing to attend the 28^th General Assembly of the International Astronomical Union （IAU）. This is a grand event for astronomy. It is the first time for China to host an IAU General Assembly since China joined the IAU in 1935. On behalf of President HU Jintao, the Chinese Government, and the Chinese people, I am here to express our warm congratulations to this General Assembly, and express our sincere gratitude and cordial welcome to all attendants.
文摘At all times and in all countries of the world, people have been fascinated by obtaining deeper insights into life and have eagerly absorbed new knowledge from around the globe. Thus in addition to trade, the sciences early on became one of the most fruitful areas of worldwide exchange and international communication. Today, it is still often the sciences that bridge national and cultural differences between countries. The Chinese Academy of Sciences and the Max Planck Society can proudly look back
文摘For centuries, the continuous development of science and technology has greatly promoted the process of mankind's understanding and utilization of nature, and at the same time strongly enhanced exchanges and cooperation between various nationalities and different civilizations. In the modern era, science and technology are developing vigorously and changing with each passing day. Strengthening international scientific cooperation is invaluable in
文摘The 14^th General Meeting of TWAS was held in Beijing nine years ago. Today, we are celebrating the 23^rd General Meeting of TWAS here in Tianjin, which is indeed a grand gathering of the international scientific community. First of all, on behalf of the Chinese people and government, I would like to extend our hearty congratulations on the convening of this meeting and our warm welcome to all TWAS Fellows, scientists and delegates from around the world.
文摘PCIM China, international conference and exhibition for power electronics, was held in Shanghai on March 21, 2006. PCIM is one of the most authoritative organizations and has won good reputation overseas for a long time.
文摘It is with great interest that I read the book Up and Out of Poverty,written by Chinese President Xi Jinping.The book was originally published in 2016,but remains highly topical today.Besides the struggle against poverty,which,in itself,is an essential issue of governance in modern times,President Xi addresses various other important issues in the book,including the relations and links between cadres and local people,pursuit of excellence in work,quality of state administration,industrial policies,education,cul tural construction,ethical rules in governance,etc.
文摘24 China Textile Top Interview Swiss Textile Machinery: Many of the innovations will integrate digitalisation and sustainability Interview with Mr. Ernesto Maurer, President of Swissmem, Swiss Textile Machinery Association ITMA 2019 will demonstrate the “inventive DNA” of Switzerland’s machinery producers. Swissmem is keen to emphasise the spirit of inventiveness which has brought history-making breakthroughs as diverse as the chocolate bar, fizzy drinks and the computer mouse – as well as a continuing stream of textile-related innovations for which ITMA will provide the latest evidence.
文摘2004 was a year of continuous progression and development along the reform of Chinese electric industry, and a year of facing great challenge and opportunity of development, in this unordinary year, guided by the concept of scientific development, the electric power sectors grasped the nettle, made progress volitionally, held together on teamwork, and pushed forward all-round, coordinated and sustainable development of the power industry.
文摘Over the next 20 years,China's urban rail transit(hereinafter referred to as'urban rail')will face large-scalerenovation of existing line facilities and equipment,with more than 1000 km of renovated lines to be added eachyear.In 2024,the China Association of Metros issued the Guiding Opinions on the Renovation of Existing UrbanRail Transit Lines in China,providing guiding opinions on norms,standards,and implementation approaches forthe renovation of existing lines in the coming period.In the practical work of renovating existing urban rail lines,it is necessary to continuously explore and refine relevant theoretical methods in line with industry developmenttrends and urban development requirements.The following are the author's recent reflections on theoreticalinnovation in this field.
文摘It is normal for an association to issue publications,for they serve as the means for communication among members,as well as between members and the association.Certainly,publications may range from a few pages of a newsletter to some kind of bulletin or magazine with lots of news concerning the subjects of interest.The most desired form of publication that an association would like to do,though not always realized,is a scientific journal.However,to publish a journal is not a simple matter;many factors that point to the success or failure of such an enterprise abound.
文摘The past 2 years we now have behind us have demonstrated the importance of understanding the dynamics of zoonotic diseases in the wild and how the disease agents spill over to the human population.At the end of 2021,Integrative Zoology published 2 special subsections on this topic,one of which focuses on plague—a zoonotic infectious disease which through history has ravaged the world.Plague,caused by the bacterium Yersinia pestis,continues to cause deaths among people.I am quite confident that we will not get rid of wildlife plague,but human plague epidemics might be history in the not too distant future(Baril et al.2019;Vallès et al.2020).
基金supported by the National Natural Science Foundation of China(No.71974162 and No.7231101009).
文摘Objectives This study aimed to develop and preliminarily assess the quality of a Mindfulness Breast Care(MBC)App to reduce body image distress and stigma among breast cancer survivors(BCSs).Methods The development process of the MBC App involved:1)establishing a research group;2)determining of the content of the MBC App based on Mindfulness-Based Cognitive Therapy and 3)technical exploitation and maintenance.A mixed-methods study was conducted.We selected ten BCSs by a convenience sampling method.After using the APP for three months,five assessed the quality using the Mobile App Rating Scale:User Version(uMARS)and another five were interviewed for process evaluation.Results The MBC App was developed with three modules:1)Library to provide health education information on body image,stigma,mindfulness,recovery and etc;2)Mindfulness Yoga to offer 12 Hatha yoga videos for daily practice;and 3)Mindfulness Practices to have 12 sessions of mindfulness videoconferences.Based on the uMARS data,the MBC App received high ratings for functionality(4.10±0.34),aesthetics(3.93±0.55),information quality(4.10±0.72),and perceived impact(4.03±0.96),as well as moderate ratings for engagement(3.72±0.94)and subjective quality(3.87±0.77).Participants indicated that the MBC App provided reliable knowledge,information,and emotional support.Recommendations from participants included categorizing knowledge in the Library Module,recording videoconferences of mindfulness practice,and adding discussion sessions in the videoconference.Afterward,we optimized the MBC App to enhance the user experience accordingly.Conclusions The MBC App offers online mindfulness interventions specifically for BCSs in China.The preliminary quality assessment indicates that the MBC App may be a promising tool for delivering mindfulness interventions to BCSs.
基金supported by Brazilian agencies CAPES(Finance Code 001)CNPq through PQ productivity scholarship.
文摘Here we compare the efficacy of anti-obesity drugs alone or combined with exercise training on body weight and exercise capacity of obese patients.Randomized clinical trials that assessed the impact of any anti-obesity drug alone or combined with exercise training on body weight,body fat,fat-free mass and cardiorespiratory fitness in obese patients were retrieved from Pubmed and EMBASE up to May 2024.Risk of bias assessment was performed with RoB 2.0,and the GRADE approach assessed the certainty of evidence(CoE)of each main outcome.We included four publications summing up 202 patients.Two publications used orlistat as an anti-obesity drug treatment,while the other two adopted GLP-1 receptor agonist(liraglutide or tirzepatide)as a pharmacotherapy for weight management.Orlistat combined with exercise was superior to change body weight(mean difference(MD):−2.27 kg;95%CI:−2.86 to−1.69;CoE:very low),fat mass(MD:−2.89;95%CI:−3.87 to−1.91;CoE:very low),fat-free mass(MD:0.56;95%CI:0.40–0.72;CoE:very low),and VO_(2)Peak(MD:2.64;95%CI:2.52–2.76;CoE:very low).GLP-1 receptor agonist drugs combined with exercise had a great effect on body weight(MD:−3.96 kg;95%CI:−5.07 to−2.85;CoE:low),fat mass(MD:−1.76;95%CI:−2.24 to−1.27;CoE:low),fat-free mass(MD:0.50;95%CI:−0.98 to 1.98;CoE:very low)and VO_(2)Peak(MD:2.47;95%CI:1.31–3.63;CoE:very low).The results reported here suggest that exercise training remains an important approach in weight management when combined with pharmacological treatment.
基金the Ministry of Science and Higher Education of the Russian Federation(Ural Federal University Program of Development within the Priority-2030 Program)is gratefully acknowledged.
文摘Improving the specific,technical,economic,and environmental characteristics of piston engines(ICE)operating on alternative gaseous fuels is a pressing task for the energy and mechanical engineering industries.The aim of the study was to optimize the parameters of the ICE working cycle after replacing the base fuel(propane-butane blend)with syngas from wood sawdust to improve its technical and economic performance based on mathematical modeling.The modeling results were verified through experimental studies(differences for key parameters did not exceed 4.0%).The object of the study was an electric generator based on a single-cylinder spark ignition engine with a power of 1 kW.The article describes the main approaches to creating a mathematical model of the engine working cycle,a test bench for modeling verification,physicochemical properties of the base fuel(propane-butane blend),and laboratory syngas.It was shown that replacing the fuel from a propane-butane blend to laboratory syngas caused a decrease in engine efficiency to 33%(the efficiency of the base ICE was 0.179 vs.the efficiency of 0.119 for the converted ICE for the 0.59 kW power mode).Engine efficiency was chosen as the key criterion for optimizing the working cycle.As a result of optimization,the efficiency of the converted syngas engine was 6.1%higher than that of the base engine running on the propane-butane blend,and the power drop did not exceed 8.0%.Thus,careful fine-tuning of the working cycle parameters allows increasing the technical and economic characteristics of the syngas engine to the level of ICEs running on traditional types of fuel.
文摘Industry and energy continue to require piston engines(PICE)at a high level worldwide.Therefore,science and technology must urgently work on improving the PICE working cycle.Improving the quality of the intake process of theworking fluid into the cylinder is one of the most effective ways to improve the operational performance of PICE.The purpose of the study was to assess the impact of various cylinder head(CylH)designs on the gas-dynamic and heat-exchange qualities of air flows within an engine model’s intake system.Three different CylH designs were studied:the basic configuration and upgraded cylinder heads with a square valve and a square valve port.These designs are innovative.Laboratory conditions were used to conduct the studies for stationary air flow.The experiments covered the range of Reynolds numbers from 8500 to 96,000.The intake system’s gas dynamics and heat transfer were determined using the thermal anemometry method,which was based on constant-temperature hot-wire anemometers.It has been established that the use of upgraded CylHs causes an increase in the turbulence number of flow by an average of 13.5%.Additionally,itwas found that the increase in the turbulence number of flowin the cylinder is about 19%when installing new CylH designs.It was shown that therewas an increase in the heat transfer coefficient in the intake pipe by 10%–40%when installing modernized CylH designs in the intake system.The article focused on the problems of increasing the turbulence level and intensifying the heat transfer of stationary air flow in the intake system,specifically in PICEs.The study’s findings are novel in the areas of applied gas dynamics and PICEs.
文摘We find the necessary and sufficient conditions on a coproduct of connected acts over a semigroup to be strongly hopfian. From this, we deduce the conditions of the strong hopfness for unitary acts over groups. Moreover, we prove that a finite coproduct of strongly hopfian acts over an arbitrary semigroup is strongly hopfian.
文摘Mongolia is a landlocked country with limited infrastructure and high dependence on the Xingang Tianjin port in China for imports. This research examines the potential impacts of establishing a dry port in Zamyn-Uud, Mongolia, utilizing a system dynamics modeling approach via Vensim software. The study evaluates transportation time, costs, inflation, and logistics performance index improvements, revealing that the establishment of the dry port can reduce transportation costs and delays significantly while enhancing economic growth. The findings offer actionable insights for policymakers and stakeholders in addressing logistical inefficiencies and fostering sustainable development in landlocked regions.
文摘As a major principle underlying the Communist Party of China's(CPC)governance in the new era and a core piece of its holistic approach to national security,ensuring both development and security emphasizes comprehensive governance from a long-term perspective and influences the world with its global vision.It keeps pace with the times by prioritizing innovative areas and is of great theoretical and practical significance.On the new journey ahead,we must firmly ensure both development and security.More importantly,we must ensure both high-quality development and high-level security,safeguarding the former through the latter.This is an urgent requirement we face in today's world,which has entered a period of turbulence and transformation characterized by increasing complexity.Confronted with the formidable tasks of promoting reform and development while maintaining stability at home and the grave challenges brought about by international turbulence and changes,we must earnestly implement the guiding principles of the 20th CPC National Congress and the third plenary session of the 20th Party Central Committee.We should ensure secure and sustainable development,accelerate efforts to modernize China's national security system and capacity,foster high-level security,and improve the mechanisms for preserving national security in foreign-related affairs.In short,we should strive to achieve a positive interplay between high-quality development and high-level security,so as to effectively safeguard Chinese modernization.
