In this paper, a test system was developed in which a CCD camera was used as a sensor together with an IBM-AT-compatible computer with an Intel 80486 processor to measure the impurities and neps on a piece of cotton g...In this paper, a test system was developed in which a CCD camera was used as a sensor together with an IBM-AT-compatible computer with an Intel 80486 processor to measure the impurities and neps on a piece of cotton gray goods, and a method was proposed by which the differences of degree of gray between samples and interference caused by surface unevenness, creasing and the like within a test sample can be removed effectively. The whole test system is reliable, accurate and causing fewer subjective errors.展开更多
Defect free yarn is a great demand for spinner, knitter, and weaver and also other textile personnel because numerous end products from knit apparels to woven fabrics, from towels to sheets and from carpets to industr...Defect free yarn is a great demand for spinner, knitter, and weaver and also other textile personnel because numerous end products from knit apparels to woven fabrics, from towels to sheets and from carpets to industrial fabrics characteristics significantly depend on the physical properties of yarn. The qualities of rotor yarn are really directed by spinning parameters. The aim of this study is to observe the effect of spinning parameters such as rotor diameter and speed on thick, thin places and neps of yarn in rotor spinning process. 0.11 sliver hank of 100% cotton was used to produce 12 Ne yarn. 65% virgin cotton and 35% wastage cotton were mixed together. The positive impact of spinning parameters on yarn properties were accessed by thick places, thin places and neps. Results indicate that the yarn qualities were improved with increasing of rotor speed and rotor diameter. The rotor diameter was settled to 43 mm while rotor speed fluctuated from 35,000 to 45,000 rpm and rotor speed was fixed to 35,000 rpm while rotor diameter across contrasts from 43 mm to 66 mm.展开更多
Based on eddy covariance(EC) measurements during 2016–20, the effects of sky conditions on the net ecosystem productivity(NEP) over a subtropical “floating blanket ” wetland were investigated. Sky conditions were d...Based on eddy covariance(EC) measurements during 2016–20, the effects of sky conditions on the net ecosystem productivity(NEP) over a subtropical “floating blanket ” wetland were investigated. Sky conditions were divided into overcast, cloudy, and sunny conditions. On the half-hourly timescale, the daytime NEP responded more rapidly to the changes in the total photosynthetic active radiation(PARt) under overcast and cloudy skies than that under sunny skies. The increase in the apparent quantum yield under overcast and cloudy conditions was the greatest in spring and the least in summer. Additionally, lower atmospheric vapor pressure deficit(VPD) and moderate air temperature were more conducive to enhancing the apparent quantum yield under cloudy skies. On the daily timescale, NEP and the gross primary production(GPP) were higher under cloudy or sunny conditions than those under overcast conditions across seasons. The daily NEP and GPP during the wet season peaked under cloudy skies. The daily ecosystem light use efficiency(LUE) and water use efficiency(WUE) during the wet season also changed with sky conditions and reached their maximum under overcast and cloudy skies, respectively. The diffuse photosynthetic active radiation(PAR_d) and air temperature were primarily responsible for the variation of daily NEP from half-hourly to monthly timescales, and the direct photosynthetic active radiation(PAR_b) had a secondary effect on NEP. Under sunny conditions, PAR_b and air temperature were the dominant factors controlling daily NEP. While daily NEP was mainly controlled by PAR_d under cloudy and overcast conditions.展开更多
There has been an increasing recognition of the crucial role of forests, responsible for sequestering atmospheric CO_(2), as a moral imperative for mitigating the pace of climate change. The complexity of evaluating c...There has been an increasing recognition of the crucial role of forests, responsible for sequestering atmospheric CO_(2), as a moral imperative for mitigating the pace of climate change. The complexity of evaluating climate change impacts on forest carbon and water dynamics lies in the diverse acclimations of forests to changing environments. In this study, we assessed two of the most common acclimation traits, namely leaf area index and the maximum rate of carboxylation(V_(cmax)), to explore the potential acclimation pathways of Pinus koraiensis under climate change. We used a mechanistic and process-based ecohydrological model applied to a P. koraiensis forest in Mt. Taehwa, South Korea. We conducted numerical investigations into the impacts of(i) Shared Socioeconomic Pathways 2–4.5(SSP2-4.5) and 5–8.5(SSP5-8.5),(ii) elevated atmospheric CO_(2) and temperature, and(iii) acclimations of leaf area index and V_(cmax)on the carbon and water dynamics of P. koraiensis. We found that there was a reduction in net primary productivity(NPP) under the SSP2-4.5 scenario, but not under SSP5-8.5, compared to the baseline, due to an imbalance between increases in atmospheric CO_(2) and temperature. A decrease in leaf area index and an increase in V_(cmax)of P. koraiensis were expected if acclimations were made to reduce its leaf temperature. Under such acclimation pathways, it would be expected that the well-known CO_(2) fertilizer effects on NPP would be attenuated.展开更多
The patterns and trends in formal higher education are changing.As world economy is moving towards a knowledge based economy,the needs and requirements of formal higher education are also changing.Countries are curren...The patterns and trends in formal higher education are changing.As world economy is moving towards a knowledge based economy,the needs and requirements of formal higher education are also changing.Countries are currently reevaluating their options of formalizing their growing education sector by drafting new education policy that aims to meet the demands of this futuristic knowledge based and technology driven economy with involvement of Artificial Intelligence and Machine Learning(AIML).Factors addressing core competence of employability,holistic development and attainment of skills are the new mantras of evolving modern day’s economy.To be in sync with such demand,requirement,and challenges,the Indian government took a significant step in drafting a New Education Policy popularly known as‘NEP 2020’.This paper makes an attempt to analyze the significant characteristics and dimensions of this NEP 2020 by undertaking a survey among stakeholders mostly students to arrive at certain key findings such as inducing centric,employable,skillful,and holistic development of students attaining such higher education.It also points out some of the implementation issues which require lead time to be adjusted with the system.展开更多
西南高山地区生态系统类型丰富、地形复杂,是响应全球气候变化的重点区域,对全球气候变化具有重要的指示作用。应用生态系统模型(Carbon Exchange between Vegetation,Soil,and the Atmosphere,CEVSA)模型估算了1954—2010年西南高山地...西南高山地区生态系统类型丰富、地形复杂,是响应全球气候变化的重点区域,对全球气候变化具有重要的指示作用。应用生态系统模型(Carbon Exchange between Vegetation,Soil,and the Atmosphere,CEVSA)模型估算了1954—2010年西南高山地区净生态系统生产力(NEP)的时空变化,分析了其对气候变化的响应。结果表明:(1)1954—2010年西南高山地区NEP平均为29.7 g C.m-.2a-1,其中低海拔地区常绿针叶林和常绿阔叶林NEP较高,而高海拔地区的草地覆盖类型NEP较低。(2)西南高山地区NEP总量的变动范围为-8.36—29.4Tg C/a,平均每年吸收碳15.4Tg C;NEP年际下降趋势显著(P<0.05),平均每年减少0.187Tg C,下降显著的区域占研究地区总面积的35.2%(P<0.05),其中草地(-0.526 g C.m-.2a-2,P<0.01)和常绿针叶林(-0.691 g C.m-.2a-2,P<0.01)下降趋势极为显著。(3)年NEP总量的年际变化与年平均温度呈负相关(r=-0.454,P<0.01),与年降水量呈正相关(r=0.708,P<0.01),与温度显著负相关的区域占60.3%(P<0.05),与降水显著正相关的区域占52.1%(P<0.05),其中草地和常绿针叶林均与温度极显著负相关(r=-0.603,P<0.01;r=-0.485,P<0.01),而与降水量极显著正相关(r=0.554,P<0.01;r=0.749,P<0.01)。(4)西南高山地区是明显的碳汇区,但是由于土壤异养呼吸(HR,heterotrophic respiration)的增长速度大于净初级生产力(NPP,net primary production)的增长速度,最近20a有部分地区开始由碳汇转为碳源。展开更多
东北地区处于我国最高纬度地区,是全球气候变化最敏感的区域之一,研究东北地区净生态系统生产力对气候变化的响应,对阐明北半球中高纬度陆地生态系统碳源汇格局具有重要意义。基于CEVSA(Carbon Exchange between Vegetation,Soil and At...东北地区处于我国最高纬度地区,是全球气候变化最敏感的区域之一,研究东北地区净生态系统生产力对气候变化的响应,对阐明北半球中高纬度陆地生态系统碳源汇格局具有重要意义。基于CEVSA(Carbon Exchange between Vegetation,Soil and Atomasphere)模型,对1961—2010年东北地区净生态系统生产力NEP的时空格局及变化趋势进行分析,并探讨了气候变化与区域碳源汇的关系。结果表明:(1)1961—2010年,东北地区年NEP总量在-0.094PgC/a—0.117PgC/a之间波动,年平均0.026PgC/a,占全国NEP总量的15%—37%。过去50年东北区域NEP没有明显的线性变化趋势,20世纪80年代碳吸收量最高,20世纪90年代后碳吸收量开始下降。(2)东北地区NEP的空间分布呈现出东部高,西部和中部低,北部高,南部低的空间格局。过去50年来,碳源区向大气释放的碳量在减少,碳汇区从大气吸收的碳也在减少。(3)NEP的年际变化与温度呈负相关(r=-0.343,P<0.05),与降水呈显著正相关(r=0.859,P<0.01),东北地区NEP和年降水量的变化规律基本一致,即同期上升或达到最高值,温度和降水共同作用导致东北地区NEP的年际变化,而年降水量的变化对NEP年际变化起主要作用。在空间上,东北地区NEP与降水呈极显著正相关(P<0.01)的面积占研究区域总面积的91.5%,与温度呈显著负相关(P<0.05)的面积占31.6%,降水也是决定NEP空间分布的最主要因子。(4)升温伴随降水增加导致1961—1990年NEP呈增加趋势,而其后升温伴随降水减少则是近20年东北区域碳汇能力减弱的重要原因。展开更多
文摘In this paper, a test system was developed in which a CCD camera was used as a sensor together with an IBM-AT-compatible computer with an Intel 80486 processor to measure the impurities and neps on a piece of cotton gray goods, and a method was proposed by which the differences of degree of gray between samples and interference caused by surface unevenness, creasing and the like within a test sample can be removed effectively. The whole test system is reliable, accurate and causing fewer subjective errors.
文摘Defect free yarn is a great demand for spinner, knitter, and weaver and also other textile personnel because numerous end products from knit apparels to woven fabrics, from towels to sheets and from carpets to industrial fabrics characteristics significantly depend on the physical properties of yarn. The qualities of rotor yarn are really directed by spinning parameters. The aim of this study is to observe the effect of spinning parameters such as rotor diameter and speed on thick, thin places and neps of yarn in rotor spinning process. 0.11 sliver hank of 100% cotton was used to produce 12 Ne yarn. 65% virgin cotton and 35% wastage cotton were mixed together. The positive impact of spinning parameters on yarn properties were accessed by thick places, thin places and neps. Results indicate that the yarn qualities were improved with increasing of rotor speed and rotor diameter. The rotor diameter was settled to 43 mm while rotor speed fluctuated from 35,000 to 45,000 rpm and rotor speed was fixed to 35,000 rpm while rotor diameter across contrasts from 43 mm to 66 mm.
基金funded by the National Natural Science Foundation of China (Grant No. 91937301)the Second Tibetan Plateau Scientific Expedition and Research (STEP) program (Grant No. 2019QZKK0105)the National Natural Science Foundation of China (Grant Nos. 41975017, 41905010)。
文摘Based on eddy covariance(EC) measurements during 2016–20, the effects of sky conditions on the net ecosystem productivity(NEP) over a subtropical “floating blanket ” wetland were investigated. Sky conditions were divided into overcast, cloudy, and sunny conditions. On the half-hourly timescale, the daytime NEP responded more rapidly to the changes in the total photosynthetic active radiation(PARt) under overcast and cloudy skies than that under sunny skies. The increase in the apparent quantum yield under overcast and cloudy conditions was the greatest in spring and the least in summer. Additionally, lower atmospheric vapor pressure deficit(VPD) and moderate air temperature were more conducive to enhancing the apparent quantum yield under cloudy skies. On the daily timescale, NEP and the gross primary production(GPP) were higher under cloudy or sunny conditions than those under overcast conditions across seasons. The daily NEP and GPP during the wet season peaked under cloudy skies. The daily ecosystem light use efficiency(LUE) and water use efficiency(WUE) during the wet season also changed with sky conditions and reached their maximum under overcast and cloudy skies, respectively. The diffuse photosynthetic active radiation(PAR_d) and air temperature were primarily responsible for the variation of daily NEP from half-hourly to monthly timescales, and the direct photosynthetic active radiation(PAR_b) had a secondary effect on NEP. Under sunny conditions, PAR_b and air temperature were the dominant factors controlling daily NEP. While daily NEP was mainly controlled by PAR_d under cloudy and overcast conditions.
基金supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT)(No.2021R1C1C1004801)。
文摘There has been an increasing recognition of the crucial role of forests, responsible for sequestering atmospheric CO_(2), as a moral imperative for mitigating the pace of climate change. The complexity of evaluating climate change impacts on forest carbon and water dynamics lies in the diverse acclimations of forests to changing environments. In this study, we assessed two of the most common acclimation traits, namely leaf area index and the maximum rate of carboxylation(V_(cmax)), to explore the potential acclimation pathways of Pinus koraiensis under climate change. We used a mechanistic and process-based ecohydrological model applied to a P. koraiensis forest in Mt. Taehwa, South Korea. We conducted numerical investigations into the impacts of(i) Shared Socioeconomic Pathways 2–4.5(SSP2-4.5) and 5–8.5(SSP5-8.5),(ii) elevated atmospheric CO_(2) and temperature, and(iii) acclimations of leaf area index and V_(cmax)on the carbon and water dynamics of P. koraiensis. We found that there was a reduction in net primary productivity(NPP) under the SSP2-4.5 scenario, but not under SSP5-8.5, compared to the baseline, due to an imbalance between increases in atmospheric CO_(2) and temperature. A decrease in leaf area index and an increase in V_(cmax)of P. koraiensis were expected if acclimations were made to reduce its leaf temperature. Under such acclimation pathways, it would be expected that the well-known CO_(2) fertilizer effects on NPP would be attenuated.
文摘The patterns and trends in formal higher education are changing.As world economy is moving towards a knowledge based economy,the needs and requirements of formal higher education are also changing.Countries are currently reevaluating their options of formalizing their growing education sector by drafting new education policy that aims to meet the demands of this futuristic knowledge based and technology driven economy with involvement of Artificial Intelligence and Machine Learning(AIML).Factors addressing core competence of employability,holistic development and attainment of skills are the new mantras of evolving modern day’s economy.To be in sync with such demand,requirement,and challenges,the Indian government took a significant step in drafting a New Education Policy popularly known as‘NEP 2020’.This paper makes an attempt to analyze the significant characteristics and dimensions of this NEP 2020 by undertaking a survey among stakeholders mostly students to arrive at certain key findings such as inducing centric,employable,skillful,and holistic development of students attaining such higher education.It also points out some of the implementation issues which require lead time to be adjusted with the system.
文摘西南高山地区生态系统类型丰富、地形复杂,是响应全球气候变化的重点区域,对全球气候变化具有重要的指示作用。应用生态系统模型(Carbon Exchange between Vegetation,Soil,and the Atmosphere,CEVSA)模型估算了1954—2010年西南高山地区净生态系统生产力(NEP)的时空变化,分析了其对气候变化的响应。结果表明:(1)1954—2010年西南高山地区NEP平均为29.7 g C.m-.2a-1,其中低海拔地区常绿针叶林和常绿阔叶林NEP较高,而高海拔地区的草地覆盖类型NEP较低。(2)西南高山地区NEP总量的变动范围为-8.36—29.4Tg C/a,平均每年吸收碳15.4Tg C;NEP年际下降趋势显著(P<0.05),平均每年减少0.187Tg C,下降显著的区域占研究地区总面积的35.2%(P<0.05),其中草地(-0.526 g C.m-.2a-2,P<0.01)和常绿针叶林(-0.691 g C.m-.2a-2,P<0.01)下降趋势极为显著。(3)年NEP总量的年际变化与年平均温度呈负相关(r=-0.454,P<0.01),与年降水量呈正相关(r=0.708,P<0.01),与温度显著负相关的区域占60.3%(P<0.05),与降水显著正相关的区域占52.1%(P<0.05),其中草地和常绿针叶林均与温度极显著负相关(r=-0.603,P<0.01;r=-0.485,P<0.01),而与降水量极显著正相关(r=0.554,P<0.01;r=0.749,P<0.01)。(4)西南高山地区是明显的碳汇区,但是由于土壤异养呼吸(HR,heterotrophic respiration)的增长速度大于净初级生产力(NPP,net primary production)的增长速度,最近20a有部分地区开始由碳汇转为碳源。
文摘东北地区处于我国最高纬度地区,是全球气候变化最敏感的区域之一,研究东北地区净生态系统生产力对气候变化的响应,对阐明北半球中高纬度陆地生态系统碳源汇格局具有重要意义。基于CEVSA(Carbon Exchange between Vegetation,Soil and Atomasphere)模型,对1961—2010年东北地区净生态系统生产力NEP的时空格局及变化趋势进行分析,并探讨了气候变化与区域碳源汇的关系。结果表明:(1)1961—2010年,东北地区年NEP总量在-0.094PgC/a—0.117PgC/a之间波动,年平均0.026PgC/a,占全国NEP总量的15%—37%。过去50年东北区域NEP没有明显的线性变化趋势,20世纪80年代碳吸收量最高,20世纪90年代后碳吸收量开始下降。(2)东北地区NEP的空间分布呈现出东部高,西部和中部低,北部高,南部低的空间格局。过去50年来,碳源区向大气释放的碳量在减少,碳汇区从大气吸收的碳也在减少。(3)NEP的年际变化与温度呈负相关(r=-0.343,P<0.05),与降水呈显著正相关(r=0.859,P<0.01),东北地区NEP和年降水量的变化规律基本一致,即同期上升或达到最高值,温度和降水共同作用导致东北地区NEP的年际变化,而年降水量的变化对NEP年际变化起主要作用。在空间上,东北地区NEP与降水呈极显著正相关(P<0.01)的面积占研究区域总面积的91.5%,与温度呈显著负相关(P<0.05)的面积占31.6%,降水也是决定NEP空间分布的最主要因子。(4)升温伴随降水增加导致1961—1990年NEP呈增加趋势,而其后升温伴随降水减少则是近20年东北区域碳汇能力减弱的重要原因。
