In vitro Ruminal Gas Production Kinetics of Four Fodder Trees Ensiled With or Without Molasses and Urea

This study investigated if the addition of urea （U）, molasses （M） or their 1：1 （v/v） mixture during ensiling increases the nutritional value of forage from four fodder trees （Prunus persica, Leucaena esculenta, Acacia farnesiana, and Prunus domestica）. Forage samples of fodder trees were collected in triplicate （three individual samples of each species） and subjected to an in vitro gas production （GP） procedure. Fermentation at 24 h （GP 24）, short-chain volatile fatty acids （SCFA）, and microbial crude protein production （MCP）, in vitro organic matter digestibility （OMD）, metabolizable energy （ME） and dry matter degradability （DMD） were estimated. Forage samples were incubated for 72 h in an incubator at 39oC and the volume of GP was recorded at 2, 4, 6, 8, 10, 12, 24, 48, and 72 h of incubation using the reading pressure technique. The rumen fermentation profiles were highest for P. persica, which showed the highest （P〈0.0001） DMD, ME, OMD, SCFA, GP 24 and MCP. On the other hand L. esculenta had the lowest （P〈0.0001） DMD, SCFA, MCP; P. domestica had the lowest （P〈0.0001） OMD. The addition of M to silage increased （P〈0.0001） ME and OMD, as well as GP. However, the addition of U and the mixture of U and M reduced （P〈0.0001） DMD, ME, OMD, SCFA, GY 24 and MCP. These results show that P. persica has the highest nutritive value and L. esculenta the lowest for ruminants. Additionally, the addition of M to forage from fodder trees increases rumen GP and fermentation, which may improve nutrient utilization in ruminants.

Tree Productivity and Water Potential Productivity in Returning Farmland to Forest Project in Datong County, Qinghai Province

From 2002 to 2003, based on the investigation of sample plots and stem analysis of remained plantation communities in the areas of returning farmland to forest in the 1980s in Datong County, Qinghai Province, this paper studies tree productivity and moisture potential productivity of six types of plantations on the land of returning farmland to forest, such as green poplar (Populus cathayana Rehd.) and shrub mixed forest, Asia white birch (Betula platyphylla) and China spruce (Picea asperata) mixed forest, Dahurian larch (Larix gmelinii) pure forest, China spruce pure forest and Asia white birch pure forest and so on. The results show that: in sub-humid region of Loess Plateau, 3 000 trees per hm2 is a proper standard of planting density. Under current condition, the productivity index of green poplar and shrub mixed forest, Asia white birch pure forest, China spruce pure forest, and Asia white birch and China spruce mixed forest with the density of 2 1003 333 trees per hm2 can serve as potential productivity standard of actual biomass of arbor established forest. In sub-humid area, Thornthwaite Model is adopted to estimate plant climate potential productivity, which is about 8 462 kghm2穉1. The actual potential water productive efficiency of Purplecone spruce (Picea purpurea) and Asia white birch pure established forest are 17.22 and 22.14 kgmm1hm2穉1 respectively, and that of green poplar and shrub mixed established forest, and Asia white birch and China spruce mixed established forest are 21.14 and 19.09 kgmm1hm2穉1 respectively. The potential productivity of green poplar and shrub mixed forest, Asia white birch and China spruce mixed forest, China spruce pure forest and Asia white birch pure forest which have grown into forest with the density of 3 000 trees per hm2 have attained or been close to that of local climax community, which is local maximum tree productivity at present. These types of forestation models are the developing direction of the returning farmland to forest project.

Tree Network Formation in Poisson Equation Models and the Implications for the Maximum Entropy Production Principle

This paper presents not only practical but also instructive mathematical models to simulate tree network formation using the Poisson equation and the Finite Difference Method (FDM). Then, the implications for entropic theories are discussed from the viewpoint of Maximum Entropy Production (MEP). According to the MEP principle, open systems existing in the state far from equilibrium are stabilized when entropy production is maximized, creating dissipative structures with low entropy such as the tree-shaped network. We prepare two simulation models: one is the Poisson equation model that simulates the state far from equilibrium, and the other is the Laplace equation model that simulates the isolated state or the state near thermodynamic equilibrium. The output of these equations is considered to be positively correlated to entropy production of the system. Setting the Poisson equation model so that entropy production is maximized, tree network formation is advanced. We suppose that this is due to the invocation of the MEP principle, that is, entropy of the system is lowered by emitting maximal entropy out of the system. On the other hand, tree network formation is not observed in the Laplace equation model. Our simulation results will offer the persuasive evidence that certifies the effect of the MEP principle.

Study of Atlas Cedar Growth (<i>Cedrus atlantica</i>Manetti) in El M’sid Mountains (East Algeria): Productivity and Growth According to Planting Methods

The Atlas cedar (Cedrus atlantica) is one of the more valuable reforestation species in the Mediterranean areas. But this species suffers from rainfall limitation and climate changes, particularly in its originated area, North Africa. Therefore, any knowledge about the plantation practices to improve the tree water availability and the reforestation success has great importance. The current study has been undertaken in this view, i.e. to compare the growth of cedar plots located in El M’Sid Mountains, Souk Ahras department (700 km east of Algiers), according to different planting methods. The radial growth and the productivity have been measured on a cedar plot with a total surface of 165 ha. 150 ha has been planted in 1970 on hillside ditches, and 15 ha of which the majority is planted in a simple hole and some bouquets on terraces, both are originated from a complementary reforestation achieved during 1980. The results show that most of the trees planted in 1970 reach a height ranging between 10 and 17 m and a diameter between 23 and 44 cm. Even some trees were 20 m high with diameter of 65 cm. The productivity fluctuates between 3 and 8 m3/ha/year, values close to the one of natural native plots. Trees planted in 1980 reach a height ranging between 5. 5 to 7 m, and diameter between 11.5 to 23 cm. The radial growth improves that the hillside ditches help the roots anchoring and trees growth during the first season after plantation. These results indicate that the cedar tree can be used with success in areas outside the natural cedar forest presence, and that appropriate planting techniques can compensate in part the lower rainfall occurring in these chosen regeneration areas.

Comparative productivity of Prosopis cineraria and Tecomella undulata based agroforestry systems in degraded lands of Indian Desert

Tree-crop interactions were monitored by measuring tree growth characters of Prosopis cineraria L. and Tecomella undulata L. and yields of Vigna radiata （L） in agroforestry systems in degraded lands of Indian Desert. Potential competition for resource between the trees and associated crop was analyzed by measuring soil water contents, soil organic matters and NH4-N at different depths of soil layers i.e., 0-25 cm, 25-50 cm and 50-75 cm in the experimental plots. The plots size were 16 m × 18 m （D1）, 20 m × 18 m （D2） and 32 m × 18 m （D3） with tree densities of 208, 138 and 104 trees.ha^-1 after June 2002, respectively. Results showed that tree height increased by 3% to 7% during June 2002 to June 2004. Collar diameter increased by 30% and 11% in D1, 23% and 19% in D2 and 18% and 36% in D3 plots, respectively, in P. cineraria and T. undulata in two years period. The increase in crown diameter was 9% to 18% in P. cineraria and 11% to 16% in T. undulata. Tree growth was relatively greater in 2002 than in 2003. Yield of V. radiata increased linearly from D1 to D3 plots. Lowest soil water content at 1 m distance from tree base indicated greater utilization of soil water within the tree rooting zone. Concentrations of soil organic matters and NH4-N were the highest （p〈0.05） in 0-25 cm soil layer. P. cineraria was more beneficial than T. undulata in improving soil conditions and increasing crop yield by 11.1% and thus more suitable for its integration in agricultural land. The yield of agricultural crop increased when density of tree species was appropriate （i.e., optimum tree density）, though it varied with tree size and depended upon resource availability. The result indicated bio-economic benefits of optimum density of P. cineraria and T. undulata over traditional practices of maintaining random trees in farming system in arid zones.

Comparative productivity of Prosopis cineraria and Tecomella undulata based agroforestry systems in degraded lands of Indian Desert

Tree-crop interactions were monitored by measuring tree growth characters of Prosopis cineraria L.and Tecomella undulata L.and yields of Vigna radiata(L) in agroforestry systems in degraded lands of Indian Desert.Potential competition for resource between the trees and associated crop was analyzed by measuring soil water contents, soil organic matters and NH4-N at different depths of soil layers i.e., 0-25 cm, 25-50 cm and 50-75 cm in the experimental plots.The plots size were 16 m × 18 m(D1), 20 m × 18 m(D2) and 32 m × 18 m(D3) with tree densities of 208, 138 and 104 trees·ha-1 after June 2002, respectively.Results showed that tree height increased by 3% to 7% during June 2002 to June 2004.Collar diameter increased by 30% and 11% in D1, 23% and 19% in D2 and 18% and 36% in D3 plots, respectively, in P.cineraria and T.undulata in two years period.The increase in crown diameter was 9% to 18% in P.cineraria and 11% to 16% in T.undulata.Tree growth was relatively greater in 2002 than in 2003.Yield of V.radiata increased linearly from D1 to D3 plots.Lowest soil water content at 1 m distance from tree base indicated greater utilization of soil water within the tree rooting zone.Concentrations of soil organic matters and NH4-N were the highest(p<0.05) in 0-25 cm soil layer.P.cineraria was more beneficial than T.undulata in improving soil conditions and increasing crop yield by 11.1% and thus more suitable for its integration in agricultural land.The yield of agricultural crop increased when density of tree species was appropriate(i.e., optimum tree density), though it varied with tree size and depended upon resource availability.The result indicated bio-economic benefits of optimum density of P.cineraria and T.undulata over traditional practices of maintaining random trees in farming system in arid zones.

新型灌溉技术在果树中应用的研究进展

果树是我国农业中重要的支柱产业,而我国水资源匮乏是影响果树生产的瓶颈问题。近年,研究学者根据果树的需水特性、生长发育规律、栽培环境条件等因素,研制多种新型节水灌溉技术,并得到较好的试验印证效果,该文将国内外有关新型灌溉技术在果树中的研究进行综合阐述,并对今后新型灌溉技术进行展望,以期将新型灌溉技术更好地服务于果树生产、提高果园管理水平提供借鉴。

一种高效16位有符号数乘法器设计

为了进一步优化乘法器的性能,提高乘法运算单元的运算速率,本文基于Radix 4 Booth算法和Wallace树压缩结构提出了一种改进的16位有符号数乘法器。其特点包括优化Radix 4 Booth编码方式,有效减小部分积选择电路的面积;改进部分积计算过程,通过优化取反加1的方法直接生成被乘数的相反数,同时采用经典的符号位补偿算法使得部分积阵列变得规整易压缩;提出一种新型42压缩器,采用单个全加器处理压缩器的中间进位,针对每行部分积不同的数据特征,细化处理了Wallace树压缩结构,提高了部分积的压缩效率。基于SMIC 180 nm标准单元库进行了综合与验证,结果表明本文所设计的乘法器关键路径延时为3.94 ns,面积为16246μm^(2),相比于现有的乘法器,本文乘法器的运算速率和综合性能都得到显著提升。

Productivity and energy balance of forest plantation harvesting in Uganda

The study evaluated the productivity and energy balance of the harvesting and the extraction of wood in plantation of exotic tree species, i.e., Pinus patula （Schiede ex Schlectendahl et Chamisso） and Cupressus lusitanica （Mill.）. The harvesting and extraction operations concerned clear-cut felling on two different types of terrain （gentle and steep terrain） and two levels of prun- ing. The results show that cutting is not affected by the terrain gradient whereas the pruning condition shows a significant effect on the delimbing operation. The productivity of cutting is evaluated at 28.1 m3.d-1 for unpruned trees and at 30.2 m3.d t for pruned trees. For the extraction phase, rolling was significantly affected by terrain conditions. On steep terrain, the gross productivity can be evaluated at 22.5 m3.d 1 for an extraction distance of 40 m, while for the same distance on gentle terrain the productivity decreases to 14.1 m3.d~. As a result, the steep terrain condition showed higher energy efficiency, suggesting that it is the more efficient system of extraction. The productivity model and the energy balance resulting from the study provide a better understanding of the variables af- fecting motor-manual cutting and rolling extraction in exotic plantations in Uganda.

利用向量叉积计算与二叉树追踪快速搜索封闭区域

目的自动填充等值线图的难点是自动搜索出值域相同的各个封闭区域,常用的扫描线填充和区域填充方式存在计算量大、效率不高等问题。方法针对此问题,提出利用多边形特征点的向量叉积计算结果与多边形的绘制顺逆方向之间的相关性,判定等值图中断层多边形的走向,基于构成封闭等值区域的等值线及其属性值具有的规律性性质,即等值线属性值是等值或等间距,追踪区域时利用填充边界或断层上的等值线端点创建追踪二叉树。追踪相邻的两个等值线端点所在的封闭区域时,将其中一个端点作为二叉树的根节点,沿边界查找左右相邻的下一条等值线端点,并将找到的端点作为左右子节点,从而实现封闭区域的快速追踪;通过封闭区域面积排序确定不同区域之间相互包含关系,据此构建拓扑相邻关系树,实现封闭区域的顺序覆盖填充,设计出更加简单、快速区分不同封闭区域的区域填充颜色选取方法。结果该方法简化了复杂的等值连通区域搜索算法,等值图的颜色变化趋势能保持一致,数据测试对比证明了所提算法的正确性。结论该算法通过一系列等值线能一次性得到组成封闭区域边界的点集合,因此,可以实现等值线和等值区域边界的完全吻合,当某些等值线发生变化时,只需更新相关的等值区域即可,提高了等值图件的编辑效率。

基于“三教”改革的“果树生产技术”课程思政探索

“三教”改革是新时代高等职业教育发展的关键核心。为促进高职专业课课程思政改革,课程团队以高职园艺技术专业核心课程“果树生产技术”教学为例,分析了“果树生产技术”课程思政的必要性、现状和存在问题。并从“三教”改革的视角,研究了如何挖掘、融入课程思政元素,实施课程思政教育,探索课程思政与职业技能培养的有机融合方式,提高职业院校园艺类专业人才培养质量,为其他专业课程进行课程思政教育和“三教”改革提供借鉴。

Tree Automata for Extracting Consensus from Partial Replicas of a Structured Document

In an asynchronous cooperative editing workflow of a structured document, each of the co-authors receives in the different phases of the editing process, a copy of the document to insert its contribution. For confidentiality reasons, this copy may be only a partial replica containing only parts of the (global) document which are of demonstrated interest for the considered co-author. Note that some parts may be a demonstrated interest over a co-author;they will therefore be accessible concurrently. When it’s synchronization time (e.g. at the end of an asynchronous editing phase of the process), we want to merge all contributions of all authors in a single document. Due to the asynchronism of edition and to the potential existence of the document parts offering concurrent access, conflicts may arise and make partial replicas unmergeable in their entirety: they are inconsistent, meaning that they contain conflictual parts. The purpose of this paper is to propose a merging approach said by consensus of such partial replicas using tree automata. Specifically, from the partial replicas updates, we build a tree automaton that accepts exactly the consensus documents. These documents are the maximum prefixes containing no conflict of partial replicas merged.

双高建设背景下《果树生产技术》课程模块化项目教学设计与实践

模块化项目教学是整合模块教学和项目化教学并运用于教学的新模式,该文在总结已有《果树生产技术》课程模块化项目教学设计的基础上,依托双高专业群建设需要,提出了符合现代职教理念的模块化项目教学设计,按照果园生产岗位能力要求设计采收及芽前管理、开花期管理以及果园环境条件等11个教学模块,并整合成果园周年管理和果园建立2个教学项目,创设情景开展教学,提高人才培养质量。

Net Primary Productivity and Management Potential of Artificial Pinus tabulaeformis Forest in Shanxi Province

The dynamic variation of net primary productivity of artificial Pinus tabulaeformis forest was studied in Shanxi Province,and potential productivity of artificial forest was predicted to provide reference for improving quality of regional forest stand. The regression equation was established by using the stratification and harvesting method with the relative growth model. Cumulative method and Thornthwaite Memorial model was used to estimate the actual and potential productivity of the forest. The productivity of P. tabulaeformis forest increased with the increase of age and started decrease with the mature period. The actual productivity of P. tabulaeformis forest was 4. 462 t/( ha·year); the contribution rate of trees was 72. 17% of the total productivity,and with the increase of age,the total biomass increased but productivity decreased at late near-mature forest; the contribution rate of herb layer was 21. 16% in the young forest stage,and then decreased gradually. On the contrary,the contribution rate of shrub layer increased gradually,and the contribution rate of the grassland was more than that of the herb layer,so as the key period of structural management; the average potential productivity of forest was 8. 422 t/( ha·year),and the potential space of P. tabulaeformis was at least 32% in Shanxi Province. In conclusion,the potential space of productivity of P. tabulaeformis was at least 32%,and the primary limiting factor of P. tabulaeformis forest productivity in Shanxi Province was rainfall.

Agro-Ecological Adaptation and Participatory Evaluation of Multipurpose Tree and Shrub Legumes in Mid Altitudes of Sud-Kivu, D. R. Congo

Livestock is traditionally managed in mixed crop-livestock production systems in Sud-Kivu, D. R. Congo. Currently, livestock production is facing numerous constraints due to wars and insecurity in the country, with looting of animals, demographic pressure on natural resources, and lack of extension services. Multipurpose trees and shrubs with adequate forage quality could help overcome dry-season feed shortage. The objective of this research was to assess the agro-ecological adaptability of selected forage tree and shrub legumes combined with farmer participatory evaluation. The study was carried out at two distinct mid-altitude sites in Sud-Kivu. Trees and shrubs were planted randomly in eleven lines, with each species/accession consisting of nine plants split into three replications. Following a standardization cut after one year of growth, regular biomass harvests were performed every eight weeks during one year;Desmodium and Flemingia were cut at 0.5 m above soil surface, while Leucaena and Calliandra at 1 m. Before every harvest, plant height was measured and number of stems counted. Fresh leaf and stem biomass were weighted, sub samples dried and leaves analyzed for nutritive value. Results from agronomic evaluation show that Leucaena diversifolia ILRI 15551 and Leucaena leucocephala had the highest yield in the rainy season on fertile soil;during dry season, Leucaena diversifolia ILRI 15551 was superior. On poor soil, Flemingia macrophylla CIAT 17403 performed best in both seasons, however, its forage quality was relatively low. Forage tree and shrub legumes chosen by farmers were, in general, the same as those superior ones in agronomic evaluation.

基于故障树和产生式规则的故障诊断专家系统设计

[目的]为充分运用核动力装置的运行管理经验辅助核动力操纵人员进行故障诊断,设计一种船用核动力装置故障诊断专家系统。[方法]首先,根据故障树与产生式规则之间的逻辑一致性,提出一种将故障树知识转化为产生式规则的方法;然后,对采用正、反向混合推理方法的专家系统知识库和推理机进行优化设计,并依据故障树最小割集和重要度分析结果设计正向推理策略以简化推理流程;最后,根据人工对故障状态判断的思路设计状态监测模块,实时采集关键设备参数以转化为专家系统可识别的设备信息。[结果]结果显示,采用所提方法可解决专家系统知识获取困难的问题,能在保证推理准确度的前提下提升推理效率,实现了专家系统的在线故障诊断功能。[结论]研究表明采用所提方法可提升专家系统获取知识的能力和推理效率,对保障核动力装置的运行管理安全具有重要意义。

基于事件树连锁故障推演和证据推理的制氢站设备风险评价

针对制氢站系统复杂,易受到外部攻击,进而引发连锁故障及严重安全事故的问题,采用基于事件树的连锁故障推演方法,明确了制氢站设备连锁故障的后果和发生概率。在此基础上建立了考虑安全性、经济性和环保性的连锁故障风险评价指标体系。考虑到造成严重后果和影响的不精确性和不确定性,采用模糊隶属度函数进行评价指标的模糊化。最后建立了基于证据推理的风险评价模型,并应用到制氢站设备的风险评估中,实现了制氢站设备的风险评价和排序。实例分析表明,该方法可行有效,为下一步制定制氢站设备安全防范措施提供了依据。

阔叶红松林林木与林分生长对采伐干扰的响应

提升森林质量、修复生态功能是东北阔叶红松林生态修复的核心,而阐明林木与林分生长对采伐干扰的响应机理是其中的关键。森林对采伐干扰的响应会受到空间尺度、时间尺度以及干扰程度等因素的综合影响。以往的研究侧重于比较不同采伐处理下林木生长的相对大小,而忽视了不同恢复时间下,林木和林分生长随干扰程度的变化。以吉林蛟河阔叶红松林采伐样地为对象,基于连续四次样地调查数据(2011、2013、2015、2018年),分别探讨了林木和林分生长在不同恢复阶段对不同程度采伐干扰的响应,并通过构建分段模型确定采伐干扰阈值。结果显示:林木和林分生长对采伐干扰的响应并不一致,采伐促进了林木生长,并且林木生长量随采伐强度的升高而升高;采伐降低了林分生产力,林分生产力随采伐强度的升高而降低。林木和林分生长对采伐干扰的响应存在时滞效应:林木和林分生长在采伐后两年内并无显著变化,而在采伐三年后才发生明显变化。此外,分段模型的结果显示:当保留木断面积为21.6 m^(2)/hm^(2)时,林分生产力最高,表明通过密度调整使阔叶红松林胸高断面积维持在21.6 m^(2)/hm^(2)附近,可使林分处于较高的生产力水平、促进森林恢复。研究结果能够为制定科学的阔叶红松林生态修复策略提供技术支撑。

Bayesian Network Model of Product Information Diffusion and Reasoning of Influence

Information diffusion on social media has become a key strategy in people’s daily interactions. This paper studies consumers’ participation in the product information diffusion, and analyzes the complexity of information diffusion which is affected by many factors. Prior investigations of information diffusion have primarily focused on the composition of diffusion networks with independent factors and the intricacy of the process has not been completely evaluated. The majority of prior investigations have focused on strategies and the moving forces in social media processes and the determination of influential seed nodes, with few evaluations conducted about the factors affecting consumers’ choices in information diffusion. In this study, a Bayesian network model of product information diffusion was created to examine the links between factors and consumer deportment. It revealed how those factors had an impact on each other and on consumer deportment choice. The innovation of the thesis is reflected in the exploration and analysis of the specific communication path of product information diffusion, which provides a better marketing idea and practical method for the development of mobile e-commerce. The research findings can help identify the quantitative relationships between the factors affecting the process of product information diffusion and user behavior.

茶树花的功能成分及相关产品研究进展

茶树花作为茶树生长发育过程中的副产物,具有丰富的保健功能成分和研究利用价值。中国是茶叶大国,茶树花资源丰富且开发潜力巨大。茶树花中存在丰富的保健功能成分,且与茶叶相似,对茶树花进行系统开发利用有助于增加茶农和茶企业的经济收益,实现“变废为宝”进一步提高茶产业的附加值,为茶农创造更多的经济价值。本文主要是通过文献综述的方式,收集、整理并分析近几年茶树花的研究和开发利用现状。从茶树花资源角度出发,对其生化成分的提取及近年茶树花产品开发利用现状进行综述,以期为茶树花资源的开发提供新的思路和参考,对茶产业的可持续发展具有一定的实践和经济价值。