Grundlagen zur Methodik der Verschneidung stahlbautypischer Körper in einem CAD-System

Der Effekt des praktischen Einsatzes von CAD-Systemen im Stahlbau erschöpft sich heute weitgehend in einer Verbesserung der Qualität der Planungsunterlagen und in der Verkürzung der Bearbeitungszeiten. Dabei ist bei schwierigen individuellen Konstruktionen die Einsparung an Arbeitszeit oft nicht sehr markant gegenüber einer traditionellen Arbeitsweise. Die dreidimensionale Erfassung, Speicherung und Verarbeitung von Konstruktionsdaten im Rechner verlangt neben größeren Rechenleistungen neue Verfahren für die Behandlung dieser Daten. Die Möglichkeiten der Automatisierung stahlbautypischer Produktionsvorgänge und einer variablen, computergestützten Planung erfordern wissenschaftlich-technische Betrachtungen des Gesamtproblems. Ausgehend von den Anforderungen des Stahlbaus wird ein neues dreidimensionales Volumenmodell für den rechnergestützten Entwurf und die Konstruktion erarbeitet. Es werden grundlegende Methoden zur Problembehandlung aufgezeigt. Die Methodik basiert im wesentlichen auf der Methode der Inzidenz-Matrizen, um die Beziehungen zwischen topologischen und geometrischen Informationen eines Körpers darzustellen. Die Ermittlung der lokalen Mannigfaltigkeiten wird mit dem Euler-Polyedersatz verglichen und an Beispielen demonstriert. Eine neue Methode zur Ermittlung der lokalen Mannigfaltigkeiten wird dargestellt. Stahlbauspezifische Konstruktionen werden erzeugt und ihre Gestalt nach Anforderungen verändert. Im besonderen werden stahlbauspezifische Ausklinkungen und Verschneidungen erarbeitet und an Beispielen präsentiert

Transhumance cattle production system in North Gondar, Amhara region, Ethiopia: is it sustainable?

The study was carried out in three highland woredas (districts) of Chilga, Dembia and Gondar Zuria in north Gondar Zone, Amhara Region, Ethiopia. These woredas were purposively selected because of their long experience in transhumance cattle production system. The objectives of the study were to characterize the transhumance cattle production system, identify the major constraints and forward appropriate developmental interventions for the future. Informal and formal surveys were employed to collect qualitative and quantitative data. From these woredas, a total of 180 representative households from 9 rural kebeles were selected using systematic random sampling methods. Semi-structured questionnaires and topical guidelines (checklists) were used to collect data. The results revealed that livestock production system in the highlands is characterized by mixed crop–livestock production and rainy season transhumance production system. Transhumance production system was practised mainly into the lowland areas. The major reasons why cattle were trekked to the lowlands were availability of feed (99.2%), free land for stocking (92.4%), low disease risk (25.0%) and availability of non-waterlogged areas (0.8%). Preferred locations were Metema (84.0%), Armachiho (9.6%), and Quara (4.0%) woredas, while very low percentages considered Alefa and Chilga woredas (0.8% each). The months when cattle movement started were May (69.5%), June (29.6%) and April (0 .8%), and the months of returned home were October (45.8%) and September (35.9%). Three major cattle trekking routes were identified, and the selection of routes depended on distance, availability of forage and non-crop covered areas. The first destination is Agamwuha kebele (Lemlem Terara) in Metema district, irrespective of the routes followed. About 60.3% of the cattle population of the three woredas was trekked to the lowlands during the rainy season. The number of cattle owners and the size of cattle population involved in one group were 4.3 ± 0.18 farmers and 58.8 ± 3.89 heads, respectively. The average daily milk off-take, lactation yield and lactation length of indigenous cows in the three studied areas was about 2.0 ± 0.07 litres, 540 ± 21.05 litres, and 8.9 ± 0.16 months, respectively. The mean age at first calving (AFC) and calving interval (CI) was 5.2 ± 0.30 years and 19.0 ± 0.38 months, respectively, while mean calf crop was 7.4 ± 0.47 heads. The average weaning age of calves was almost one year, being 11.6 ± 0.26 months. In the lowlands, milking, butter making and selling of dairy products were performed only by male herders. In the highland areas, butter (95.6%) was one of the most important saleable dairy products followed by raw milk (18.4%), fermented milk (ergo) and buttermilk (6.1%). However, during the transhumance period, butter (95.3%) was the major marketable commodity followed by raw milk (61.3%), buttermilk (18.9%) and fermented milk (14.2%). Highlanders also market dry cows, oxen, heifers and young bullocks during their stay inthe lowlands. The major constraints identified by the highlanders were conflict with the lowlanders, cattle theft, human and livestock diseases, and lack of markets. Most of the respondents (86.3%) estimated that the trend of transhumance has been increasing due to feed shortage (50.4%), expansion of crop cultivation (27.4%) and increasing cattle population (21.2%) in the highlands. Human population has also been increasing both in the highlands and lowlands, and the current infrastructure development in the lowlands (tarmac road, electricity, phone etc.) will further encourage more migration to the lowlands. The conflict over resources will intensify, probably leading to the demise of this production system unless alterative development strategies, such as intensification of the production system in the highlands and development of feed conservation and marketing in the lowlands are devised

Selecting for food-feed traits in desi and kabuli genotypes of chickpea (Cicer arietinum)

The study explored the genetic and environmental variability in chickpea for food-feed traits. Seventy nine genotypes of 17 early-maturing desi genotypes, 19 early-maturing kabuli genotypes and 43 late-maturing kabuli genotypes were evaluated for food-feed traits in 7 trials laid out in a randomized complete block design in 3 locations in Ethiopia. All trials showed wide genotypic ranges in various traits related to grain yield, straw yield and straw quality. Analysis of variance for individual trials showed significant (P<0.05) effects of genotype, location and their interaction on grain and straw yields, CP, IVOMD and NDF in all populations. Correlation analysis exhibited either positive or insignificant correlations with straw yield in all trials. The correlation between IVOMD and grain yield was insignificant in all trials. Grain yield correlated significantly (P<0.001) and positively to NDF in early maturing kabuli, however, the correlation was moderate (r= 0.396). Grain yield correlated either weakly or insignificantly to CP and Ca in the trials. The correlation between P and grain yield was ignored as the straw content of P was very small in all genotypes (<1.78 g/kg). Weak or absence of correlations between grain yields with straw traits would enable chickpea breeders to manipulate grain yield and straw traits independently. This presents an opportunity to identify parental genotypes for improving grain yield and straw traits for individual locations

Innovative Partnership Approach to Chickpea seed production and Technology Dissemination: Lessons from Ethiopia

Innovative partnership in chickpea seed production and technology dissemination was assessed in increasing chickpea productivity through facilitated access to quality seed. The study was designed to evaluate the benefits gained from partnership implemented for the last 10 years in chickpea technology by seed system of crop production. Farmers' participatory variety selection (FPVS)' has been implemented as epicenter of the new innovation. The varieties selected by the farmers were ultimately demonstrated and visited by large number of farmers and other stakeholders. This was complemented with the establishment and technical backstopping of farmers' seed producer associations to produce and market quality seed to fill the gap by the formal sector. Intervention with chickpea technologies were initiated right after training partners in chickpea seed and grain vale chain. From 2008 to 2015, over 350 FPVS trials were conducted concurrently with demonstrations. The farmers' seed producer associations cover the lion's share of the seed supply and became an innovative approach that enhanced the chickpea seed system. The production of certified and quality declared seed increased from 632.7t in 2008 to 3290 tons in 2014. The drastic increase in productivity and production of chickpea during the intervention period were largely attributed to the interventions made. The national chickpea productivity has doubled in a decade's time (2006-2015) and attained peak of 1.9ton ha-1 in 2014. Similarly production showed drastic increase during the intervention period where the production in 2015 was 124% more compared to the production in 2006. Lessons were driven from the approach that many development parties and the government policy recognized the approach as key player for enhancing the chickpea sector

Optimizing near infrared reflectance spectroscopy to predict nutritional quality of chickpea straw for livestock feeding

Multidimensional improvement programs of chickpea require screening of a large number of genotypes for straw nutritive value. The ability of near infrared reflectance spectroscopy (NIRS) to determine the nutritive value of chickpea straw was identified in the current study. A total of 480 samples of chickpea straw representing a nation-wide range of environments and genotypic diversity (40 genotypes) were scanned at a spectral range of 1108 to 2492 nm. The samples were reduced to 190 representative samples based on the spectral data then divided into a calibration set (160 samples) and a cross-validation set (30 samples). All 190 samples were analysed for dry matter, ash, crude protein, neutral detergent fibre, acid detergent fibre, acid detergent lignin, Zn, Mn, Ca, Mg, Fe, P, and in vitro gas production metabolizable energy using conventional methods. Multiple regression analysis was used to build the prediction equations. The prediction equation generated by the study accurately predicted the nutritive value of chickpea straw (R2 of cross validation > 0.68; standard error of prediction < 1%). Breeding programs targeting improving food-feed traits of chickpea could use NIRS as a fast, cheap, and reliable tool to screen genotypes for straw nutritional quality

Incidence and predictors of puerperal sepsis among postpartum women at Debre Markos comprehensive specialized hospital, northwest Ethiopia: A prospective cohort study

Background: Puerperal sepsis is one of the leading causes of maternal mortality, particularly in low and middle-income countries where most maternal deaths occur. Women with puerperal sepsis are prone to long-term disabilities, such as chronic pelvic pain, blocked fallopian tubes, and secondary infertility. Besides this, puerperal sepsis has received less attention. For this reason, this study aimed to determine the incidence of puerperal sepsis and its predictors among postpartum women at Debre Markos Comprehensive Specialized Hospital. Methods: A prospective cohort study was conducted among 330 postpartum women from September 2020 to 2021. A pre-tested interviewer-administered questionnaire with a data extraction checklist was used to collect the data. Data were entered into Epi data 4.2 and analyzed using STATA 14.0. The incidence rate of puerperal sepsis was calculated, and a Kaplan-Meier survival curve was used to estimate the survival probability of developing puerperal sepsis. The cox-proportional hazards regression model was fitted to identify predictors of puerperal sepsis. Results: The study participants were followed for a total of 1685.3 person-week observations. The incidence rate of puerperal sepsis was 14.24 per 1,000 person-weeks. However, the overall incidence of puerperal sepsis was 7.27%. Not attending formal education [AHR: 3.55, 95% CI: (1.09–11.58)], a cesarean delivery [AHR: 4.50; 95% CI: (1.79–11.30)], premature rupture of the membranes [AHR: 3.25; 95% CI: (1.08–9.79)], complicated pregnancy [AHR: 4.80; 95% CI: (1.85–12.43)], being referred [AHR: 2.90; 95% CI: (1.10–7.65)], and not having birth preparedness and complication readiness plan [AHR: 2.95; 95% CI: (1.08–10.50)] were statistically significant predictors of puerperal sepsis. Conclusion: The incidence of puerperal sepsis was 7.27%. Not attending formal education, cesarean delivery, premature rupture of membranes, complicated pregnancy, referral status, and absence of birth preparedness and complication readiness plan were predictors associated with the incidence of puerperal sepsis

Embodying the Spirit(s): Pentecostal Demonology and Deliverance Discourse in Ethiopia

The article explores Pentecostal embodiment practices and concepts with regard to Holy Spirit baptism and demon possession. The studied material is connected to a specific and highly controversial debate in Ethiopian Pentecostalism, which revolves around the possibility of demon possession in born-again and Spirit-filled Christians. This debate runs through much of Ethiopian Pentecostal history and ultimately is concerned with whether or how Christians can host conflicting spiritual forces, in light of the strong dualism between God and evil in Pentecostal cosmology. The article shows that the embodiment of spirits and/or the Holy Spirit is related to theological concepts of the self, because these concepts define what may or may not be discerned in certain bodily manifestations. Moreover, the article contends that this debate thrives on a certain ambiguity in spirit embodiment, which invites the discernment of spiritual experts and thereby becomes a resource of power

A systems and partnership approach to agricultural research for development: Lessons from Ethiopia

In spite of the availability of several improved agricultural technologies generated by the research system in Ethiopia over the last four decades, adoption of these innovations by smallholder farmers has been very low. This has led to stagnation of agricultural productivity and low crop yields, exposing the country to recurrent food shortfalls and national food insecurity. The old approach to agricultural research emphasized developing new technologies mainly through onstation research that were then supposed to reach farmers through the public-sector extension system. The Ethiopian Institute of Agricultural Research (EIAR) has in recent years introduced a shift in agricultural research for development, which is based on the innovation systems approach that involved cultivating partnerships with several actors along the value chain, especially farmers, farmers’ cooperatives and input suppliers. This paper presents the methodology used to facilitate agricultural innovations and the diffusion of new technologies and illustrates the outcomes of this initiative with regard to technology adoption, productivity growth and the market orientation of production. The authors use examples from experiences in scaling up three grain legumes. Compared to the three-year baseline average (2003–05), crop output increased nationally by 89%, 85% and 97% in 2008 for common bean, chickpea and lentil respectively. Nationally, 53–59% of the output growth is attributable to yield growth due to technological change, while the balance is due to area expansion. These results affirm that the new approach has led to accelerated adoption of new and high-yielding or low-risk varieties