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8823 Uppsatser om Root-cause-analysis - Sida 1 av 589

När trädens rotsystem får bestämma : En intervjustudie med en grupp yrkesverksamma inom anläggning av hållbara gröna miljöer.

ABSTRACTThis pilot study examines the knowledge about tree root systems amongst five treeplanting professionals. The aim is to find out the professionals? collective knowledge ofthe nature of root systems of various trees used in green areas. Furthermore; to explorehow the professionals adapt landscaped green areas to the tree root properties in asustainable manner. Questions: Which tree species have special root properties toconsider and how do the professionals utilize this knowledge? And: How do theprofessionals in general adjust planting according to the root systems of trees in areas tocreate sustainable green environments?Interviews with the professionals were performed.

Obalans mellan rot och krona skapar omplanteringschock i Prunus avium :

In this investigation has an attempt to find out whether so called transplanting shock depends on the moving and transplanting of trees, to other conditions, or if it is due to the imbalance between the root to shoot ratio. Seventy trees of Prunus avium have been part of the investigation and these trees have been divided into four different groups depending on methods of production, untouched on the field, trees still on the field but with root pruning, trees moved and planted into Root-Control-Bag, trees moved and planted into Spring-rings. To be able to answer the question, measurements of the length of the terminal shoots and the lateral shoots and the dimension of the stem growth have been done and also has a visual judgment of the trees vitality been performed. The result shows that it is not only the move of the trees that gives them transplanting shock, but rather the loss of roots which gives an imbalance between the root and crown..

The effect of arginine on root system development in Norway spruce (Picea abies L. Karst) somatic embryos

The demands for higher production yields and better quality materials from the forests are increasing globally. Tree breeding programs are directed to meet the future demands on forests. In order to capture the full benefits from the breeding programs, clonal propagation is necessary. For most conifer species, somatic embryogenesis (SE) is the only available option for large scale clonal propagation of Elite clonal material. For Norway spruce (Picea abies L.

Risken för spridning av röta vid förröjning i granskog i södra Sverige :

Root rot causes large economical losses for Swedish forestry. The spread of root rot can partly be prevented by treating the spruce stumps in thinnings. Late pre-commercial thinning (PCT) is one of the forestry measures where stump treatment is not used. Late PCT can be defined as: The act of cleaning the stand with the aim of improving accessibility and sight within the stand, and so to increase the mean stem´s volume during the first conventional thinning. The aim of this study was to examine how late PCT is performed, its spatial extent and if it aids the spreading of root rot. The study was limited to encompass late PCT before first conventional thinnings in spruce stands in southern Sweden. Samples of spruce stumps were taken from four stands where late PTC had been carried out.

Optimering av sintrade kugghjul

Powder Metal (PM) gears are machine element components which operate under the same principle as conventional gears, but, due to their intrinsic material characteristic need to be designed slightly different, and its manufacturing process offers advantages previously unobtainable by conventional steel gear manufacturing methods. The use of PM in similar applications, such as synchronous hubs, makes them a suitable candidate for production in such material. The current master thesis work focuses on gear design using PM by utilizing finite element method (FEM) to reduce weight and inertia taking into account root bending strength and tooth deflection.First a topological optimization is used to determine feasible candidates for different web designs which have as objective to reduce volume, similar topologies were shown during different loading conditions; and hence, this topology was chosen as a suitable candidate. A shape optimization of the topological candidate was performed having as state variables root bending strength, independent for compressive and tensile side of the tooth loading; and tooth deflection, which in concept can be correlated to static transmission error (TE).Another aspect in this thesis analysed is the possibility to incorporate non-trochoid root geometry, a trochoid root is always present when machining with a hob, into the gear root and hence reduce the stress concentration here. Due to the use of PM, a non-symmetric optimized root can be achieved and hence be optimizing compression and tension.Results showed significantly lower inertia, for example certain results showed 40% reduced when compared to solid gear, with adverse effects as increase in tooth deformation and increase in maximum principal stress.

Startfosfor till höstvete :

There is always an endeavor to govern the initial products in the plant cultivation with precision in order to keep down the expenditure and in order to decrease environmental impact. Initial phosphorus fertilizer can then be one possibility in order to keep down the fertilizer cost and to decrease environmental impact. This exam study includes a literature study about location of fertilizer and which effects this give and two field experiments. The aim with initial phosphorus fertilizer to autumn wheat is to accelerate the root growth and to give the crop a big root system before the growth stagnates before the winter. Easy to access phosphorus favours the root growth.

Odlingsmetodernas påverkan på vitaliteten hos Prunus avium :

The objective of this study was to get a better understanding of how the cultivation methods influence the vitality in Prunus avium. The purpose was also to examine if there was any differences in shoot growth and trunk expansion depending on the method of cultivation. To find the answer to this question a literature study and a case study has been done. The literature study concerns the concepts vitality and stress. Different definitions of these concepts are shown and their connection whit establishment is explained. In the background the species Prunus avium, and the four method of cultivation that are included in this case study are described. Measurements of the shoot growth and trunk expansion were made in this study, and as a complement to these methods, a visual estimate of the vitality was made.

Terrorismens orsaker : Om skapandet av generella kausalteorier när det gäller uppkomsten av terrorism

The first of the dual purposes of this work has been to describe the research that has been done regarding the root causes of terrorism and second, using a general causal theory and examining the political dimensions of it, to discuss whether or not general causal theories (grand-theories) are helpful for researchers and policy-makers when reacting to social developments in the form of terrorism. The essay is a qualitative literature analysis and I have based my studies on mostly new books treating root causes of terrorism. I have concentrated on discussing international terrorism and how political dimensions may impact the occurence of this form of political violence. The conclusions I have made is that there is no widespread consensus among researchers and scholars as to what really causes terrorism. Neither can the general model examined in chapter 5 be used to predict when and where terrorism will occur next.

Effekten på nedbrytningen av rötter vid tillförsel av ammonium sulfat i en granskog i sydvästra Sverige

Decomposition of organic matter is a critical process in the ecosystem, which involves many essential biotic and physical parts. Decomposition is therefore an important process both above and below ground. The rate of decomposition is dependent of many environmental factors for example: pH, moisture and supply of oxygen. The decomposition can therefore be affected by large scaled environmental influences, such as acidification and climatic changes. The root litter in the forest is in different ways affected by acidification, liming and manuering.

Plasmodiophora brassicae ? host and environment interactions

In this thesis, three separate experiments have been performed on different aspects of the interaction between the causal agent of clubroot, Plasmodiophora brassicae, and its hosts. In the first experiment the pathotype of the P. brassicae single spore isolate, which is currently used to construct a reference genome, has been classified using the ECD bioassay. The disease severity of infected plants was scored according to two different scales and the pathotype was determined according to three previously published guidelines. The results were compared to previous published studies describing the e3 isolate. The life cycle of P. brassicae is not well understood.

Hedmans Kvadratrotsalgoritm

I detta 10-poängsarbete går jag igenom hur min egenhändigt producerade kvadratrotsalgoritm fungerar praktiskt och teoretiskt. Med denna algoritm kan man för hand räkna ut kvadratrötter som innehåller 50-60 värdesiffror. Med de tidigare kända algoritmerna för kvadratrötter kan man räkna ut 5-6 värdesiffror. Min algoritm fungerar inte på samma sätt som de tidigare använda kvadratrotsalgoritmerna men den är lika korrekt. Stor tyngdvikt i arbetet har därför lagts på att visa på att det finns flera olika korrekta algoritmer för våra vanliga räknesätt.

Vegetationens roll i erosiva vattendrag : en review och fältstudie av två nyckelområden i Rönne å

The vegetation?s impact on erosion control is widely explored, even though research? results are scattered where it suggests a both positive and negative relationship between roots and erosion tendency. Research has measured the roots? impact on erosion by many different methods, hence the aim of this study is to offer a clearance of what factors play an important role in the choice of appropriate species controlling river bank erosion. I have therefore studied 17 articles concerning vegetation and erosion control, which were found in different databases such as: Web of Knowledge, Biological Sciences, Academic Search Elite and Google Scholar.

Pinus contorta susceptibility to Heterobasidion spp. : a study of stumps, roots and artificial spore infections of stumps

The Lodgepole pines susceptibility to Heterobasidion spp. was investigated in three parts ofthis study. In the first part, discs from freshly cut stumps were collected and analyzed to seeif the fungi can spread and grow naturally in Lodgepole pine stands. In the second part, rootsamples were collected from Lodgepole pines planted in former infected Norway sprucestands to see if the fungi can spread through root contacts. For the third part, new stumpswas created and artificially infected with spores of both the S?type (H.

Angelica archangelica L.

Angelica archangelica (Garden angelica) is the only Medicinal and Aromatic Plant (MAP) with a Nordic origin. The plant can reach up to three meters when cultivated. Angelica archangelica is used as flavouring in additives, honey, beverage base, essential oils, fol-klore medicine and as ornamental for decorative purposes. Commercial cultivation is mainly focused on root production. Production countries are Poland, Netherland, France, Belgium, Switzerland, and former Czechoslovakia with an overall yearly world production of 1000 kg of essential oils.

Stuka. En förvaringsmetod för grönsaker under vinterhalvåret

Uppsats för avläggande av filosofie kandidatexamen i Kulturvård, Trädgårdens hantverk och design, 22, 5 hp, 2015.

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