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Analysis and Innovative Strategies of Tax Preferential Policies to Promote the Sustainable Development of Small-Scale Individual Businesses
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作者 Tiantian Wang Xinyu Yi +1 位作者 Ziyi Zhang Jingjing Xiang 《Proceedings of Business and Economic Studies》 2024年第3期120-125,共6页
This study conducted an in-depth analysis of the current tax preferential policies for small-scale individual businesses and compared them with similar policies both domestically and internationally,aiming to reveal t... This study conducted an in-depth analysis of the current tax preferential policies for small-scale individual businesses and compared them with similar policies both domestically and internationally,aiming to reveal the advantages and disadvantages of the current system.After examining the impact of these tax preferential policies on the economic status of individual business owners and the broader social economy,this article proposes a set of innovative tax preferential strategies based on theoretical foundations.By developing these innovative strategies and clarifying their implementation paths,the aim is to promote the sustainable and healthy development of small-scale individual businesses,thereby fostering comprehensive socio-economic progress.The conclusion of this study not only summarizes policy recommendations with practical significance but also provides theoretical support for the optimization and innovation of future related systems. 展开更多
关键词 small-scale individual operation Tax incentives Policy analysis Economic effects Innovation strategy
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基于SWMM和LISFLOOD-FP的城市内涝耦合模型研究 被引量:2
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作者 李智 张倩 兰双双 《水电能源科学》 北大核心 2024年第2期202-206,共5页
以柳州市箭盘山流域为例,构建SWMM一维管道模型与LISFLOOD-FP二维地面模型并将其耦合,基于实测降雨“20180818”24 h暴雨资料,将得到的暴雨内涝淹没水深和淹没面积与该场次降雨情况下记录淹没点的范围相比较,验证耦合模型具有较好的适... 以柳州市箭盘山流域为例,构建SWMM一维管道模型与LISFLOOD-FP二维地面模型并将其耦合,基于实测降雨“20180818”24 h暴雨资料,将得到的暴雨内涝淹没水深和淹没面积与该场次降雨情况下记录淹没点的范围相比较,验证耦合模型具有较好的适用性。进而基于耦合模型,对柳州市箭盘山流域2、5、10、20年一遇下设计降雨进行模拟,得到不同重现期下研究区的溢流节点、淹没水深和淹没面积,并于ARCGIS平台将结果可视化。结果表明,重现期由2年上升到20年过程中,溢流节点比例从9.03%增加至25.99%,溢流面积从0.473 km^(2)增加至2.114 km^(2);重点淹没区域分布在屏山大道、炮团路、西江路和东堤路。 展开更多
关键词 SWMM LISflood-FP 城市洪涝 耦合 箭盘山流域
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基于MIKE FLOOD模型的平原水网地区内涝治理效果模拟研究
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作者 侯俊 陈诚 +3 位作者 郑玉磊 丁伟 时间 苗令占 《水利水电科技进展》 CSCD 北大核心 2024年第6期41-47,70,共8页
为科学评估平原水网地区内涝治理效果,以昆山市淀山湖镇为研究对象,基于MIKE FLOOD模型,耦合一维河网、二维地形和一维管网模拟了平原水网地区城镇内涝情况。采用实测降雨数据对模型进行了率定和验证,并模拟了2年一遇、5年一遇、10年一... 为科学评估平原水网地区内涝治理效果,以昆山市淀山湖镇为研究对象,基于MIKE FLOOD模型,耦合一维河网、二维地形和一维管网模拟了平原水网地区城镇内涝情况。采用实测降雨数据对模型进行了率定和验证,并模拟了2年一遇、5年一遇、10年一遇和20年一遇4种重现期降雨条件下现状和治理后的最大淹没水深。模拟结果表明:20年一遇降雨条件下内涝范围变化明显,其余3种重现期降雨条件下内涝范围变化不明显;对于降雨重现期较小条件下的城市内涝治理,应优先考虑管网改造,而针对短历时的强暴雨事件,应优先考虑海绵城市设施建设改造;为了应对不同重现期、短历时降雨造成的城市内涝风险,应在管网改造的基础上配合海绵城市设施建设改造。 展开更多
关键词 平原水网 内涝治理 海绵城市设施 MIKE flood模型 淀山湖镇
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An analytical model for estimating rock strength parameters from small-scale drilling data 被引量:13
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作者 Sajjad Kalantari Alireza Baghbanan Hamid Hashemalhosseini 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2019年第1期135-145,共11页
The small-scale drilling technique can be a fast and reliable method to estimate rock strength parameters. It needs to link the operational drilling parameters and strength properties of rock. The parameters such as b... The small-scale drilling technique can be a fast and reliable method to estimate rock strength parameters. It needs to link the operational drilling parameters and strength properties of rock. The parameters such as bit geometry, bit movement, contact frictions and crushed zone affect the estimated parameters.An analytical model considering operational drilling data and effective parameters can be used for these purposes. In this research, an analytical model was developed based on limit equilibrium of forces in a Tshaped drag bit considering the effective parameters such as bit geometry, crushed zone and contact frictions in drilling process. Based on the model, a method was used to estimate rock strength parameters such as cohesion, internal friction angle and uniaxial compressive strength of different rock types from operational drilling data. Some drilling tests were conducted by a portable and powerful drilling machine which was developed for this work. The obtained results for strength properties of different rock types from the drilling experiments based on the proposed model are in good agreement with the results of standard tests. Experimental results show that the contact friction between the cutting face and rock is close to that between bit end wearing face and rock due to the same bit material. In this case,the strength parameters, especially internal friction angle and cohesion, are estimated only by using a blunt bit drilling data and the bit bluntness does not affect the estimated results. 展开更多
关键词 ANALYTICAL model ROCK strength PARAMETERS small-scale DRILLING data
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Numerical Simulation for Accuracy of Velocity Analysis in Small-Scale High-Resolution Marine Multichannel Seismic Technology 被引量:5
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作者 LUO Di CAI Feng WU Zhiqiang 《Journal of Ocean University of China》 SCIE CAS CSCD 2017年第3期370-382,共13页
When used with large energy sparkers, marine multichannel small-scale high-resolution seismic detection technology has a high resolution, high-detection precision, a wide applicable range, and is very flexible. Positi... When used with large energy sparkers, marine multichannel small-scale high-resolution seismic detection technology has a high resolution, high-detection precision, a wide applicable range, and is very flexible. Positive results have been achieved in submarine geological research, particularly in the investigation of marine gas hydrates. However, the amount of traveltime difference information is reduced for the velocity analysis under conditions of a shorter spread length, thus leading to poorer focusing of the velocity spectrum energy group and a lower accuracy of the velocity analysis. It is thus currently debatable whether the velocity analysis accuracy of short-arrangement multichannel seismic detection technology is able to meet the requirements of practical application in natural gas hydrate exploration. Therefore, in this study the bottom boundary of gas hydrates(Bottom Simulating Reflector, BSR) is used to conduct numerical simulation to discuss the accuracy of the velocity analysis related to such technology. Results show that a higher dominant frequency and smaller sampling interval are not only able to improve the seismic resolution, but they also compensate for the defects of the short-arrangement, thereby improving the accuracy of the velocity analysis. In conclusion, the accuracy of the velocity analysis in this small-scale, high-resolution, multi-channel seismic detection technology meets the requirements of natural gas hydrate exploration. 展开更多
关键词 small-scale HIGH-RESOLUTION multichannel seismic velocity analysis accuracy gas hydrate
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Weak wide-band signal detection method based on small-scale periodic state of Duffing oscillator 被引量:3
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作者 Jian Hou Xiao-peng Yan +1 位作者 Ping Li Xin-hong Hao 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第3期205-215,共11页
The conventional Duffing oscillator weak signal detection method, which is based on a strong reference signal, has inherent deficiencies. To address these issues, the characteristics of the Duffing oscillator's phase... The conventional Duffing oscillator weak signal detection method, which is based on a strong reference signal, has inherent deficiencies. To address these issues, the characteristics of the Duffing oscillator's phase trajectory in a small- scale periodic state are analyzed by introducing the theory of stopping oscillation system. Based on this approach, a novel Duffing oscillator weak wide-band signal detection method is proposed. In this novel method, the reference signal is discarded, and the to-be-detected signal is directly used as a driving force. By calculating the cosine function of a phase space angle, a single Duffing oscillator can be used for weak wide-band signal detection instead of an array of uncoupled Duffing oscillators. Simulation results indicate that, compared with the conventional Duffing oscillator detection method, this approach performs better in frequency detection intervals, and reduces the signal-to-noise ratio detection threshold, while improving the real-time performance of the system. 展开更多
关键词 Duffing oscillator weak signal detection stopping oscillation system small-scale periodic state
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Factors affecting technical efficiency of small-scale apple farms in Balochistan Plateau, Pakistan 被引量:2
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作者 Ghulam MURTAZA Gopal Bahadur THAPA 《Journal of Mountain Science》 SCIE CSCD 2017年第4期782-794,共13页
In Balochistan, Agriculture is dominated by small-scale farmers and the apple production sector is confronted with the chronic constraint of low output per unit of input. Although some agricultural policies have been ... In Balochistan, Agriculture is dominated by small-scale farmers and the apple production sector is confronted with the chronic constraint of low output per unit of input. Although some agricultural policies have been implemented in this province, studies on effectiveness and impacts of such policies over apple production and farmers' performance are still limited. This study is an effort to bridge the research gap on this potential crop in the plateau by investigating technical and scale efficiency of 181 officially designated small-scale apple farmers in mountainous district Mastung in Balochistan; then explored factors that underlie differences in production inefficiency. A two-stage input-oriented Data Envelopment Analysis(DEA) methodology was employed to evaluate technical and scale efficiency followed by truncated bootstrapped regression framework to analyze the correlative determinants to efficiency. Average technical and scale efficiencies of larger landholders were higher than medium and small landholders. Analysis indicated that there is still ample scope for inefficient sample farmers to reduce the input use by 33% without compromising the given yield level. Maximum contributions to the total input savings were from the use of urea, farm yard manure(FYM) and labor-use. Farmer's experience, farm ownership, irrigation constraints, and farmer's access to trainings, credit and extension services significantly affected apple farmers' technical efficiency. Based on the findings of this study, strategies are suggested to enhancing efficiencies by farmers' capacity development through effective extension services and trainings and provision of adequate credit. 展开更多
关键词 small-scale apple farmers Technical efficiency Data envelopment analysis (DEA) BOOTSTRAP Efficiency-improving resources Balochistan Plateau
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Shock-induced fracture of dolomite rock in small-scale blast tests 被引量:1
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作者 Pawel Baranowski Michal Kucewicz +1 位作者 Mateusz Pytlik Jerzy Matachowski 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2022年第6期1823-1835,共13页
This paper attempts to study dolomite failure using small-scale blast tests.The experimental setup consisted of a cylindrical specimen with a central borehole fitted with a detonation cord inside a copper pipe.The spe... This paper attempts to study dolomite failure using small-scale blast tests.The experimental setup consisted of a cylindrical specimen with a central borehole fitted with a detonation cord inside a copper pipe.The specimen was confined using lead material.During the test,acceleration histories were recorded using sensors placed on the lead confinement.The results showed that heterogeneity and initial cracks significantly influenced the observed failure and cracking patterns.The tests were numerically represented using the previously validated Johnson-HolmquistⅡ(JH-2)constitutive model.The properties of the detonation cord were first determined and verified in a special test with a lead specimen to compare the deformation in the test with that of numerical simulation.Then,the small-scale blast test was simulated,and the failure of the dolomite was compared with the test observations.Comparisons of acceleration histories,scabbing failure,and number of radial cracks and crack density confirmed the overall repeatability of the actual testing data.It is likely that the proposed model can be further used for numerical studies of blasting of dolomite rock. 展开更多
关键词 Johnson-HolmquistⅡmodel(JH-2) ROCK BLASTING FRACTURE small-scale test
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Study on the Roles of FWUA in Construction, Management and Maintenance of Small-Scale Irrigation and Water Conservancy 被引量:1
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作者 Shaoshu LI Ke YUAN 《Asian Agricultural Research》 2013年第4期139-144,共6页
In recent years, China has been frequented by floods and droughts which has greatly evoked much concern from the Central Government about rural water conservancy construction. Irrigation is closely related to the &quo... In recent years, China has been frequented by floods and droughts which has greatly evoked much concern from the Central Government about rural water conservancy construction. Irrigation is closely related to the "three rural" issues and concerns about the vital interests of farmers. To achieve a virtuous circle of agricultural water supply, it is necessary and urgent to establish Farmer Water User Association (FWUA) to participate in the construction, management and maintenance of small-scale irrigation system. Based on the survey on nationwide "Small-scale irrigation conditions", the roles of FWUA in the construction, management and maintenance of small-scale water conservancy have studied in this study. 展开更多
关键词 small-scale IRRIGATION FWUA CONSTRUCTION Managemen
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Effect of high-or low-speed fluctuations on the small-scale bursting events in an active control experiment 被引量:1
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作者 Xiao-Tong Cui Nan Jiang Zhan-Qi Tang 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第1期319-327,共9页
Active control of a fully developed turbulence boundary layer(TBL) over a flat plate has been investigated with a statistical view. The piezoelectric(PZT) oscillator is employed to produce periodic input into the inne... Active control of a fully developed turbulence boundary layer(TBL) over a flat plate has been investigated with a statistical view. The piezoelectric(PZT) oscillator is employed to produce periodic input into the inner region of the TBL.A wall probe is fixed upstream of the oscillator to identify the high-or low-speed fluctuations as the detecting signals.Then, the impact of the detecting signals on the small-scale bursting process is investigated based on the data acquired by the traversing probe downstream of the oscillator. The results indicate that the small-scale bursting intensity is restrained more apparently at high-speed detecting fluctuations but less impacted at low-speed detecting fluctuations. Furthermore, the perturbed-scale fluctuations arrange the small-scale bursting process in the near-wall region. The detecting signals have an obvious impact on this arrangement, especially the high-intensity regions of the small-scale bursting events: the vibration enhances the intensity at high-speed detecting signals but weakens it at low-speed detecting signals in these regions, which gives a direct evidence on how detecting signals interfering the small-scale bursting process. 展开更多
关键词 turbulent boundary layer active control discrete wavelet decomposition small-scale bursting process
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Small-Scale Tomato Cultivators’ Perception on Pesticides Usage and Practices in Buea Cameroon 被引量:1
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作者 Tinyami Erick Tandi Choi Jae Wook +2 位作者 Tumenta Terence Shendeh Eko Alain Eko Chick Ofilia Afoh 《Health》 2014年第21期2945-2958,共14页
It has been shown that farmers with limited knowledge of the use and safe handling of pesticides may suffer exposure which results in adverse health effects. In Buea, Cameroon, small-scale tomato farmers commonly use ... It has been shown that farmers with limited knowledge of the use and safe handling of pesticides may suffer exposure which results in adverse health effects. In Buea, Cameroon, small-scale tomato farmers commonly use pesticides for pest control. Information was obtained from these tomato farmers to determine the extent and types of their pesticide use, their knowledge of pesticide use and effectiveness, and their perception of potential harm resulting from pesticide use. A standardized questionnaire, interviews, field observations and an analytical ranking game were used to describe the pesticide use of 93 tomato farmers. Many farmers (47.6%) used pyrethiod and organophosphorus insecticides and identified these chemicals as the most effective in pesticide control;these are WHO Class II pesticides which are the most hazardous to humans. Most farmers (83.8%) used knapsack sprayers to apply pesticides, with 76.3% using no or partial personal protective equipment (PPE). It was notable that 55.5% of farmers expressed no concern regarding the wind direction (pesticide drift) during spraying. The results showed a significant association between the method of pesticides application and farm size (P < 0.001). Most farmers (85.0%) reported at least one symptom of acute pesticide poisoning following spraying. This study revealed that the tomato farmers have a high exposure to pesticides secondary to inadequate knowledge of the safe and judicious use of pesticides. Strategies that provide training on the appropriate use of pesticides, how to reduce exposure to and health risks of pesticides and alternative options of pest management and control are required. The study also raised concerns that further control of the sale and distribution of pesticides may be indicated. 展开更多
关键词 small-scale FARMING TOMATO Cultivation PESTICIDES POISONING Cameroon
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Processes of small-scale tidal flat accretion and salt marsh changes on the plain coast of Jiangsu Province,China 被引量:2
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作者 ZHANG Yunfeng ZHANG Zhenke +3 位作者 HE Huachun CHEN Yingying JIANG Songliu REN Hang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2017年第4期80-86,共7页
Large-scaled reclamation modifies the coastal environment dramatically while accelerating the disappearance of salt marshes,which causes the degradation of the coastal ecosystem and the biodiversity function.In this s... Large-scaled reclamation modifies the coastal environment dramatically while accelerating the disappearance of salt marshes,which causes the degradation of the coastal ecosystem and the biodiversity function.In this study,we explored the changes of tidal flat and salt marsh coverage in a small-scale tidal flat with an area of ~160 000 m^2 in the plain coast of Jiangsu Province,China.Human activities(e.g.,the construction of dikes) are a crucial contributor that benefits for the tidal flat accretions and the following changes of salt marsh coverage.Located in the front of the man-made "concave coastline",the study area is suitable for sediment accretion after the dike construction in the end of 2006.On the basis of the annual tidal surface elevation survey from 2007 to 2012,the sedimentation rates in the human influenced tidal flat varied from a few centimeters per year to 23 cm/a.The study area experienced a rapid accretion in the tidal flat and the expansion of the salt marsh,with the formation of a longshore bar,and a subsequent decline of the salt marsh.Breaking waves during the flooding tide brought much sediment from the adjacent tidal flat to the study area,which caused burial and degeneration of the salt marsh.The vertical grain size changes within a 66 cm long core in the study area also demonstrated the above changes in the tidal environment.This study indicates that the responses of small-scale tidal flat changes to reclamation are significant,and the rational reclamation would benefit for the new salt marsh formation in front of the dikes.Further research about the evolution of small scale tidal flat as well as the spatial planning of the polder dike should be strengthened for the purpose to maintain a healthier coastal environment. 展开更多
关键词 tidal flat salt marsh small-scale tidal flat response to reclamation plain coast of Jiangsu Province
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基于MIKE FLOOD耦合模型模拟的城市内涝对道路安全风险的影响评估
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作者 程麒铭 刘霖皓 +4 位作者 刘非 毛钧 苏义鸿 何旸 陈垚 《中国农村水利水电》 北大核心 2024年第8期94-104,共11页
城市内涝风险评估对预防洪涝灾害有重要作用,但现有研究很少针对道路安全风险评估。以重庆市秀山县为研究对象,通过构建MIKE FLOOD耦合模型对道路安全风险进行评估。结果表明:地面积水深度主要集中在0.05~0.15 m,不同重现期(P=1%~20%)... 城市内涝风险评估对预防洪涝灾害有重要作用,但现有研究很少针对道路安全风险评估。以重庆市秀山县为研究对象,通过构建MIKE FLOOD耦合模型对道路安全风险进行评估。结果表明:地面积水深度主要集中在0.05~0.15 m,不同重现期(P=1%~20%)降雨下的水深在空间分布上大体呈一致状态,积水时间主要集中在60~90 min,积水流速主要大于0.8 m/s。其中,老城区部分区域的基础设施安全风险以极高风险(水深>0.4 m)为主,其余区域为轻微风险(水深<0.5 m)为主,而行人安全风险以Ⅲ级(危险性指数1.25~2)为主,其余区域则以Ⅰ级(危险性指数<0.75)为主。大部分路段的交通运行状况以畅通等级(保留系数>0.7)为主,但部分路段遇暴雨时中断(保留系数=0)。研究结果可为城市内涝发生前的交通管控和通行预警提供科学依据。 展开更多
关键词 城市内涝 MIKE flood 内涝风险 道路安全评估
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Climate change drives flooding risk increases in the Yellow River Basin 被引量:1
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作者 Hengxing Lan Zheng Zhao +9 位作者 Langping Li Junhua Li Bojie Fu Naiman Tian Ruixun Lai Sha Zhou Yanbo Zhu Fanyu Zhang Jianbing Peng John J.Clague 《Geography and Sustainability》 CSCD 2024年第2期193-199,共7页
The Yellow River Basin(YRB)has experienced severe floods and continuous riverbed elevation throughout history.Global climate change has been suggested to be driving a worldwide increase in flooding risk.However,owing ... The Yellow River Basin(YRB)has experienced severe floods and continuous riverbed elevation throughout history.Global climate change has been suggested to be driving a worldwide increase in flooding risk.However,owing to insufficient evidence,the quantitative correlation between flooding and climate change remains illdefined.We present a long time series of maximum flood discharge in the YRB dating back to 1843 compiled from historical documents and instrument measurements.Variations in yearly maximum flood discharge show distinct periods:a dramatic decreasing period from 1843 to 1950,and an oscillating gentle decreasing from 1950 to 2021,with the latter period also showing increasing more extreme floods.A Mann-Kendall test analysis suggests that the latter period can be further split into two distinct sub-periods:an oscillating gentle decreasing period from 1950 to 2000,and a clear recent increasing period from 2000 to 2021.We further predict that climate change will cause an ongoing remarkable increase in future flooding risk and an∼44.4 billion US dollars loss of floods in the YRB in 2100. 展开更多
关键词 flooding risk Risk management Climate change flood discharge Extreme precipitation
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The Human Dimension in the UNESCO Kogelberg Biosphere Reserve:Integrating Livelihood Issues of Small-Scale Fisheries with the Conservation of Natural Resources
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作者 Inka Schomer 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期86-86,共1页
Fisheries management worldwide struggles to strike a balance between protecting resources,ensuring fair access to resources and promoting economic effectiveness and stability.The transition to a participatory democrac... Fisheries management worldwide struggles to strike a balance between protecting resources,ensuring fair access to resources and promoting economic effectiveness and stability.The transition to a participatory democracy in South Africa in 1994 resulted in the transformation of government institutions and an extensive process of legislative reform regarding 展开更多
关键词 CONSERVATION small-scale FISHERIES marine RESOURCES LIVELIHOOD strategies
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Small-Scale Duplications Play a Significant Role in Rice Genome Evolution
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作者 Guo Xin-yi Xu Guo-hua ZHANG Yang Hu Wei-min FAN Long-jiang 《Rice science》 SCIE 2005年第3期173-178,共6页
Genes are continually being created by the processes of genome duplication (ohnolog) and gene duplication (paralog). Whole-genome duplications have been found to be widespread in plant species and play an importan... Genes are continually being created by the processes of genome duplication (ohnolog) and gene duplication (paralog). Whole-genome duplications have been found to be widespread in plant species and play an important role in plant evolution. Clearly un-overlapping duplicated blocks of whole-genome duplications can be detected in the genome of sequenced rice (Oryza sativa). Syntenic ohnolog pairs (ohnologues) of the whole-genome duplications in rice were identified based on their syntenic duplicate lines. The paralogs of ohnologues were further scanned using multi-round reciprocal BLAST best-hit searching (E〈e^-14). The results indicated that an average of 0.55 sister paralogs could be found for every ohnologue in rice. These results suggest that small-scale duplications, as well as whole-genome duplications, play a significant role in the two duplicated rice genomes. 展开更多
关键词 small-scale duplication ohnologue genome evolution Oryza sativa ARABIDOPSIS
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Density disturbance of small-scale fieldaligned irregularities in the ionosphere heating experiments
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作者 Xiang WANG Chen ZHOU +2 位作者 Moran LIU Binbin NI Zhengyu ZHAO 《Plasma Science and Technology》 SCIE EI CAS CSCD 2018年第12期9-18,共10页
A theoretical model which describes the small-scale irregularities excited by powerful high frequency (3–30 MHz) electromagnetic wave in ionosphere heating is investigated quantitatively in this paper. The model is... A theoretical model which describes the small-scale irregularities excited by powerful high frequency (3–30 MHz) electromagnetic wave in ionosphere heating is investigated quantitatively in this paper. The model is based on the transport equation in magnetic plasma and mode conversion from electromagnetic wave to electrostatic wave in ionospheric modification.Threshold electric field for exciting small-scale (meter scale) irregularities and spatial spectra of irregularities are analytically calculated by this model. The results indicate that background electron density and geomagnetic field play an important role for the threshold electric field and the spatial scale of the electron density irregularities. The results demonstrate that the electric field threshold increases with the decrease of the spatial scale of the irregularities. For exciting meter scale irregularities, the threshold electric field is about tens of mV m^(-1). The theoretical results are consistent with those of the experiments. 展开更多
关键词 small-scale irregularities ionosphere heating experiment thermal parametric instability resonant instability
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Adoption of small-scale irrigation technologies and its impact on land productivity:Evidence from Rwanda
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作者 Jules NGANGO Seungjee HONG 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2021年第8期2302-2312,共11页
In an attempt to identify solutions to the effects of erratic rainfall patterns and droughts that limit agricultural production growth,the Rwandan government has recently increased investments in irrigation developmen... In an attempt to identify solutions to the effects of erratic rainfall patterns and droughts that limit agricultural production growth,the Rwandan government has recently increased investments in irrigation development.In this study,we analyze the adoption of small-scale irrigation technologies(SSITs)and its impact on land productivity using cross-sectional data from a sample of 360 farmers in Rwanda.The study uses the propensity score matching technique to address potential self-selection bias.Our results reveal that adoption decisions are significantly influenced by factors such as education,farm size,group membership,gender,extension services,access to credit,access to weather forecast information,risk perceptions,access to a reliable source of water for irrigation,awareness of rainwater harvesting techniques,and awareness of subsidy programs.In addition,the results show that the adoption of SSITs has a significantly positive impact on land productivity.The study concludes with policy implications that highlight the need to promote the adoption of SSITs among farmers as a strategy to improve agricultural productivity and food security in Rwanda. 展开更多
关键词 small-scale irrigation maize production Rwanda technology adoption impact assessment propensity score matching
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Impact of Small-scale Production Mode on Citrus Industry of Hunan Province,China——Based on the Investigation on Citrus Industry in Shimen County
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作者 HU Zhi-dan1,WANG Kui-wu2,BO Xin1,TAN Jie2 1.College of Humanities,Hunan Agricultural University,Changsha 410128,China 2.Department of Scientific Research,Hunan Agricultural University,Changsha 410128,China 《Asian Agricultural Research》 2010年第3期38-40,共3页
Small-scale farmer is defined by the domestic and foreign experts and scholars.They point out that since the fragmentation of production and the diseconomy of scale in small-scale farmer is inconsistent with the chara... Small-scale farmer is defined by the domestic and foreign experts and scholars.They point out that since the fragmentation of production and the diseconomy of scale in small-scale farmer is inconsistent with the characteristics of scale and technology of modern agricultural production,it is necessary to eliminate the adverse effects of existing mode in order to provide theoretical references for the relevant researches.Citrus industry in Shimen County,Hunan Province,China is introduced from the aspects of natural geographical condition and socio-economic benefit.Impact of small-scale production mode on citrus production in Shimen County is discussed.Firstly,blindness of small-scale production is the main reason leading to overproduction of citrus.Secondly,small-scale production mode has limitation on the acceptance of new technologies,restricts the operation of geographical trademark,and constraints the enthusiasm of enterprises in entering the agricultural field.Finally,suggestions are put forward,such as encouraging the circulation of rural land,improving the organization degree of farmers,changing the work function of grass-roots government and perfecting the agricultural financial credit system. 展开更多
关键词 small-scale PRODUCTION MODE CITRUS INDUSTRY Geogra
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Case Study:Promoting Sustainable Energy Greenhouse Heating Systems to Small-Scale Local Farms
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作者 Jeremy Ferrell Ok-Youn Yu Heiyoung Kim 《Journal of Agricultural Science and Technology(A)》 2020年第4期165-180,共16页
Biomass energy generated from livestock manure,other agricultural by-products and food waste can be an affordable greenhouse-heating energy source for those seeking lower energy costs.Appalachian State University,Nort... Biomass energy generated from livestock manure,other agricultural by-products and food waste can be an affordable greenhouse-heating energy source for those seeking lower energy costs.Appalachian State University,North Carolina(NC),USA,has built a 6.1 m×9.1 m greenhouse,called the“Nexus”to test the integrated sustainable energy heating system for growing season extension with less energy cost.This is done by using on-farm biomass resources/wastes such as agricultural waste and wood chips to produce energy coupled with solar water heating to store and supplement required thermal inputs.Growing season extension with heated greenhouses increases the availability of local food throughout the year,expands available markets and increases farmers’profits.Nexus includes an above ground 5,680-L water storage tank and an aquaculture pond.It is supported by a small-scale pyrolysis system,an anaerobic digestion system,solar thermal and compost heating.The preliminary result showed that compared to a conventional space heating system,about 30%of energy was saved to keep the greenhouse temperature available for growing by radiation from the water storage tank.The main purpose of this study was to test the proposed greenhouse heating systems developed at Nexus by implementing pilot systems on two local farms.Pyrolysis and solar thermal system in conjunction with heat storage and delivery system for each farm were built and tested in order to demonstrate how to reduce greenhouse energy use.This paper describes the results of the case study,which showed significant energy savings that can promote the resource-limited farmers’interest. 展开更多
关键词 GREENHOUSE sustainable energy farms heating system small-scale.
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