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One DOF mechanism for the mechanical harvest of vines in an arbor structure and the validation of the

Osvaldo PENISI,José BOCCA,Horacio AGUILAR,Pedro BOCCA

《机械工程前沿（英文）》 2015年 第10卷 第3期   页码 221-232 doi: 10.1007/s11465-015-0347-9

摘要：

In the mechanized harvest of vines, grape berries are detached through the vibration to the structure supporting the clusters. According to the kind of guide selected, the clusters require one or two vibration directions in the structure. For guiding in parral structures, vibration is necessary in two directions or planes: One perpendicular to the other. The guide branches producing the clusters develop in these planes, and the guiding is called H-guiding. Mechanism theory indicates that a mechanism has as many degrees of freedom as its actuators, and an actuator is needed to achieve a certain vibration. Having the smallest number of possible actuators is beneficial in reducing moving parts and achieving more compact and easily controllable mecha-nisms. In this case, a single degree-of-freedom mechanism is proposed. It is capable of generating vibrations on two planes: One perpendicular to the other. This mechanism is the sum of two link mechanisms on perpendicular planes with a common outlet located at the output rod of the mechanism where the actuator is found. As the distance between the soil and the elements containing the clusters is not constant, a system has been designed to measure the accelerations at the bars and the rocker to validate the acceleration values that detach the grape berries in a prototype in a lab experiment, to ensure that the acceleration needed for pulling the grape berries are produced at any contact point of the bar.

关键词： harvest     mechanisms     one DOF     vibration    

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Hip-mounted electromagnetic generator to harvest energy from human motion

Dan DAI,Jing LIU

《能源前沿（英文）》 2014年 第8卷 第2期   页码 173-181 doi: 10.1007/s11708-014-0301-2

摘要： A type of electromagnetic hip-mounted generator (EHG) is proposed to harvest energy from human hip motion to generate electricity. Based on the law of electromagnetic induction, the EHG generator can convert the kinetic power of the thigh swing into electrical energy during walking or running. To demonstrate the feasibility of the present method, a prototype of the EHG has been designed and fabricated. A theoretical analysis has been conducted to interpret the working behavior of this prototype. In addition, the performance of the system has been experimentally tested through a rotary motor and human body motion. When driven by the rotary motor at a rotation speed of 100 r/min, the open-circuit voltage of this prototype is 2.5 V. Further, a maximum open-circuit voltage of approximately 1 V and a maximum output power of 284 μW could be produced respectively when walking with an EHG at a speed of 1.47 m/s. This handy renewable energy technology is promising as a pervasive electricity generation system for a group of wearable or implanted sensors, actuators and mobile electronics.

关键词： human power harvesting     pervasive energy     electricity generation     wearable energy     renewable and sustainable energy     mobile electronics    

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Breeding for pre-harvest sprouting resistance in bread wheat under rainfed conditions

Muhammad ZEESHAN, Waheed ARSHAD, Muhammad Imran KHAN, Shiraz ALI, Ali NAWAZ, Amina BATOOL, Muhammad TARIQ, Muhammad Imran AKRAM, Muhammad Amjad ALI

《农业科学与工程前沿（英文）》 2018年 第5卷 第2期   页码 253-261 doi: 10.15302/J-FASE-2018218

摘要： Pre-harvest sprouting in wheat is the germination of seeds within the spikes when rains occur after or during grain ripening, which occurs commonly in the barani tract of Pakistan. Therefore, 10 cultivars and five advanced lines of spring bread wheat were evaluated for pre-harvest sprouting resistance. After natural rainfall, seeds were immediately collected from the wet spikes and tested for germinating ability. Three different germination tests were applied to hand-threshed seed: (1) spikes threshed on the day of sampling and germination tested immediately, (2) spikes threshed on the day of sampling and germination tested 1 week later, and (3) spikes threshed 1 week after sampling and germination test immediately after threshing. Seeds and spikes kept for 1 week were place on blotting paper at room temperature. Cultivars BARS-09, 09FJ17, Doukkala-12, NARC-09 and Ouassou-20 exhibited higher sprouting resistance while other genotypes were susceptible to pre-harvest sprouting in each of the three tests. A diallel crossing was conducted with six susceptible and two resistant genotypes to assess the genetic behavior of pre-harvest sprouting resistance. The combining ability (CA) demonstrated a higher proportion of additive genetic effects for sprouting resistance, because of higher variance of general and specific CA for both parameters under study. Doukkala-12 and BARS-09 showed increased pre-harvest sprouting resistance in their F descendants.

关键词： bread wheat     germination index     general combining ability     pre-harvest sprouting     specific combining ability    

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Influence of harvest date on seed yield and quality in forage kochia

Cody F. CREECH, Blair L. WALDRON, Corey V. RAMSOM, Dale R. ZOBELL, Joseph Earl CREECH

《农业科学与工程前沿（英文）》 2018年 第5卷 第1期   页码 71-79 doi: 10.15302/J-FASE-2017196

摘要： Forage kochia ( ) is used for rangeland reclamation and livestock and wildlife forage, but limited research has been conducted on its seed production. Therefore, this research evaluated the effect of harvest date on seed weight, germination, and seed yield of forage kochia subspecies and . Seed was harvested from individual plants for 3 years during October, November, and December. October harvest had the lightest 100-seed weights, with the November harvest slightly heavier than December, for most accessions. Cultivar Snowstorm and breeding line Sahsel, both subsp. , had the greatest 100-seed weights in November, 155 and 143 mg, respectively, whereas, cv. Immigrant (subsp. ), the standard for forage kochia, ranked among the least for 100-seed weight. For most accessions, germination was lowest from the October harvest (11%–43%), with greater germination with November and December harvested seeds (43%–64%). Viable seed yields were greatest in November with the exception of two accessions, which peaked in October, indicating earlier maturity. Results indicate that forage kochia usually reaches optimum seed maturity by early November, after plants are exposed to freezing temperatures; however, earlier maturing accessions exist in both subspecies and .

关键词： forage     rangeland     seed germination     seed quality    

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Approaches to achieve high grain yield and high resource use efficiency in rice

Jianchang YANG

《农业科学与工程前沿（英文）》 2015年 第2卷 第2期   页码 115-123 doi: 10.15302/J-FASE-2015055

摘要： This article discusses approaches to simultaneously increase grain yield and resource use efficiency in rice. Breeding nitrogen efficient cultivars without sacrificing rice yield potential, improving grain fill in later-flowering inferior spikelets and enhancing harvest index are three important approaches to achieving the dual goal of high grain yield and high resource use efficiency. Deeper root distribution and higher leaf photosynthetic N use efficiency at lower N rates could be used as selection criteria to develop N-efficient cultivars. Enhancing sink activity through increasing sugar-spikelet ratio at the heading time and enhancing the conversion efficiency from sucrose to starch though increasing the ratio of abscisic acid to ethylene in grains during grain fill could effectively improve grain fill in inferior spikelets. Several practices, such as post-anthesis controlled soil drying, an alternate wetting and moderate soil drying regime during the whole growing season, and non-flooded straw mulching cultivation, could substantially increase grain yield and water use efficiency, mainly via enhanced remobilization of stored carbon from vegetative tissues to grains and improved harvest index. Further research is needed to understand synergistic interaction between water and N on crop and soil and the mechanism underlying high resource use efficiency in high-yielding rice.

关键词： rice     nitrogen-efficient cultivar     grain fill     harvest index     nitrogen use efficiency     water use efficiency    

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Improving water use efficiency in grain production of winter wheat and summer maize in the North China Plain: a review

Xiying ZHANG,Wenli QIN,Juanna XIE

《农业科学与工程前沿（英文）》 2016年 第3卷 第1期   页码 25-33 doi: 10.15302/J-FASE-2016090

摘要： Reducing irrigation water use by improving water use efficiency (WUE) in grain production is critical for the development of sustainable agriculture in the North China Plain (NCP). This article summarizes the research progresses in WUE improvement carried out at the Luancheng station located in the Northern part of NCP for the past three decades. Progresses in four aspects of yield and WUE improvement are presented, including yield and WUE improvement associated with cultivar selection, irrigation management for improving yield and WUE under limited water supply, managing root system for efficient soil water use and reducing soil evaporation by straw mulch. The results showed that annual average increase of 0.014 kg·m for winter wheat and 0.02 kg·m in WUE were observed for the past three decades, and this increase was largely associated with the improvement in harvest index related to cultivar renewal and an increase in chemical fertilizer use and soil fertility. The results also indicated that deficit irrigation for winter wheat could significantly reduce the irrigation water use, whereas the seasonal yield showed a smaller reduction rate and WUE was significantly improved. Straw mulching of summer maize using the straw from winter wheat could reduce seasonal soil evaporation by 30–40 mm. With new cultivars and improved management practices it was possible to further increase grain production without much increase in water use. Future strategies to further improve WUE are also discussed.

关键词： harvest index     cultivar selection     deficit irrigation     root water uptake     straw mulching    

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Effects of irrigation and nitrogen management on hybrid maize seed production in north-west China

Hui RAN,Shaozhong KANG,Fusheng LI,Ling TONG,Taisheng DU

《农业科学与工程前沿（英文）》 2016年 第3卷 第1期   页码 55-64 doi: 10.15302/J-FASE-2016091

摘要： Scientific irrigation and nitrogen management is important for agricultural production in arid areas. To quantify the effect of water and nitrogen management on yield components, biomass partitioning and harvest index ( ) of maize for seed production with plastic film-mulching, field experiments including different irrigation and N treatments were conducted in arid north-west China in 2013 and 2014. The results indicated that kernel number per plant ( ) was significantly affected by irrigation and N treatments. However, 100-kernel weight was relatively stable. Reducing irrigation quantity significantly increased stem partitioning index ( ) and leaf partitioning index ( ), and decreased ear partitioning index ( ) at harvest, but lowering N rate (from 500 to 100 kg N·hm ) did not significantly reduce , , and at harvest. was significantly reduced by reducing irrigation quantity, but not by reducing N rate. Linear relationships were found between , , , at harvest and and evapotranspiration ( ).

关键词： yield components     biomass partitioning     harvest index     irrigation     nitrogen     maize for seed production    

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Microalgae cultivation and culture medium recycling by a two-stage cultivation system

Xinfeng Wang, Lu Lin, Haifeng Lu, Zhidan Liu, Na Duan, Taili Dong, Hua Xiao, Baoming Li, Pei Xu

《环境科学与工程前沿（英文）》 2018年 第12卷 第6期 doi: 10.1007/s11783-018-1078-z

摘要：

A two-stage system was designed for microalgae cultivation and nutrients removal.

Two species of microalgae were cultivated for biomass production.

UF costed less than centrifuge for harvesting microalgae at small scale.

100% NH4+ of the wastewater was removed and met discharge requirement.

关键词： Microalgae harvest     Ultrafiltration     Poultry wastewater     Nutrient removal     Two stage cultivation    

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标题 作者 时间 类型 操作

One DOF mechanism for the mechanical harvest of vines in an arbor structure and the validation of the

Osvaldo PENISI,José BOCCA,Horacio AGUILAR,Pedro BOCCA

期刊论文

Hip-mounted electromagnetic generator to harvest energy from human motion

Dan DAI,Jing LIU

期刊论文

Breeding for pre-harvest sprouting resistance in bread wheat under rainfed conditions

Muhammad ZEESHAN, Waheed ARSHAD, Muhammad Imran KHAN, Shiraz ALI, Ali NAWAZ, Amina BATOOL, Muhammad TARIQ, Muhammad Imran AKRAM, Muhammad Amjad ALI

期刊论文

Influence of harvest date on seed yield and quality in forage kochia

Cody F. CREECH, Blair L. WALDRON, Corey V. RAMSOM, Dale R. ZOBELL, Joseph Earl CREECH

期刊论文

Approaches to achieve high grain yield and high resource use efficiency in rice

Jianchang YANG

期刊论文

Improving water use efficiency in grain production of winter wheat and summer maize in the North China Plain: a review

Xiying ZHANG,Wenli QIN,Juanna XIE

期刊论文

Effects of irrigation and nitrogen management on hybrid maize seed production in north-west China

Hui RAN,Shaozhong KANG,Fusheng LI,Ling TONG,Taisheng DU

期刊论文

Microalgae cultivation and culture medium recycling by a two-stage cultivation system

Xinfeng Wang, Lu Lin, Haifeng Lu, Zhidan Liu, Na Duan, Taili Dong, Hua Xiao, Baoming Li, Pei Xu

期刊论文