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Penelitian tentang analisis sifat mekanik modifikasi kemiringan mercu Spillway Tipe Ogee menggunakan metode elemen hingga software ELMER telah dilakukan. Tujuan penelitian ini adalah menganalisis besar tegangan, regangan dan deformasi pada mercu spillway bendungan tipe ogee dengan metode elemen hingga. Struktur bendungan dimodelkan dengan bantuan software FreeCAD, kemudian perhitungan metode elemen hingga dengan software Elmer dan dilanjutkan analisis dengan software ParaView. Berdasarkan hasil analisis mercu Spillway tipe Ogee dengan modifikasi kemiringan 41.18o, 45o dan 48.36o menunjukkan tegangan maksimum pada kemiringan 41.18o terjadi pada bagian dinding mercu spillway pada arah sumbu z dengan nilai 2.2 x 105 N/m2, sedangkan tegangan maksimum pada kemiringan 45o dan 48.36o terjadi pada bagian segmen dasar mercu spillway pada arah sumbu xy dengan nilai secara berurutan 2.5 x 105 N/m2 dan 3.0 x 105 N/m2. Regangan yang terjadi pada ketiga modifikasi kemiringan berurutan sebesar 35 x 10-8 , 47.5 x 10-8, dan 65 x 10-8. Deformasi yang terjadi pada ketiga modifikasi berurutan sebesar 1.4 x 10-5 m, 1.9 x 10-5 m dan 2.6x10-5 m. Dari analisis sifat mekanik modifikasi kemiringan mercu Spillway Tipe Ogee dapat disimpulkan bahwa perubahan nilai regangan dan deformasi semakin besar jika kemiringan mercu Spillway bertambah. Sedangkan nilai tegangan maksimum terjadi pada bagian dinding dan bagian segmen dasar mercu spillway. Kata Kunci : Metode Elemen Hingga, Spillway ogee, tegangan, regangan, deformasi. Abstract Research on the mechanical properties of the modification of the ogee spillway dam with slope variations has been caried out using the finite element method ELMER software. The purposes of this study were to analyze the magnitude of stress, strain and deformation on the ogee spillway. The structure of the dam was modeled with a FreeCAD software, then the calculation of the finite element method with an Elmer software and the analysis used ParaView software. Based on the analysis of the ogee spillway type with slopes of 41.18o, 45o and 48.36o, the maximum stress at the slope of 41.18o occurs in the wall section of the crest spillway in the z axis direction with a value of 2.2 x 105 N/m2, while the maximum stress at the slope of 45o and 48.36o occurs in the base segment of the crest spillway in the xy axis direction with values of 2.5 x 105 N/m2 and 3.0 x 105 N/m2 respectively. The strains that occurs in the three sequential tilt modifications were 35 x 10-8, 47.5 x 10-8, and 65 x 10-8. The deformation occurs in the three sequential modifications of 1.4 x 10-5 m, 1.9 x 10-5 m and 2.6 x 10-5 m. From the analysis of the mechanical properties of the modification of the crest spillway ogee Type it can be concluded that the change in strain and deformation values is greater if the slopes of the crest spillway increases. While, the maximum stress value occurs in the wall and the base segment of the mercu spillway. Keywords : Finite element method, spillway ogee, stress, strain, deformation.

Diese Arbeit beschäftigt sich mit den Möglichkeiten und Anwendungen der Frühmobilisation bei Patient*innen nach Gelenksersatzeingriffen. Die Implantation einer Knietotalendoprothese (KTEP) und einer Hüfttotalendoprothese (HTEP) gehört zu den am häufigsten in Deutschland durchgeführten Operationen zur Erhaltung der Gelenksbeweglichkeit und Steigerung der Lebensqualität der Patient*innen. This work deals with the possibilities and applications of early mobilization in patients after joint replacement surgery. The implantation of a total knee endoprosthesis (KTEP) and a hip endoprosthesis (HTEP) is one of the most common operations performed in Germany to maintain joint mobility and improve the patient’s quality of life.

Malnutrition und Decubitalulcera zählen weltweit zu den häufigsten Pflegephänomenen in der Praxis und stellen ein großes Gesundheitsproblem dar. Mangelernährung trägt einen wesentlichen Teil zu der Entstehung von Dekubitus bei. Daraus resultiert für die Betroffenen ein hoher Pflegebedarf, eine kostenintensive Therapie und eine verlängerte Behandlungsdauer in Gesundheitseinrichtungen. Für den gehobenen Dienst für Gesundheits- und Krankenpflege ist das frühzeitige Erkennen einer Mangelernährung und die daraus ergebenden präventiven ernährungsmedizinischen Interventionen ein wichtiger Indikator. Malnutrition and pressure ulcers are among the most common nursing phenomena in practice around the world and represent a major health problem. Malnutrition contributes significantly to the development of pressure ulcers. For those affected, this results in a high need for care, cost-intensive therapy and an extended duration of treatment in health facilities. The early detection of malnutrition and the resulting preventive nutritional medical interventions are an important indicator for the high-level service for health and nursing.

Abstrak Plastik konvensional yang sering digunakan dalam kehidupan sehari-hari menyebabkan terjadinya penumpukan limbah plastik dan menyebabkan masalah pencemaran lingkungan karena plastik sulit terurai oleh mikroorganisme. Bioplastik merupakan salah satu solusi yang digunakan dalam mengurangi pencemaran lingkungan, sifatnya yang mudah terdegradasi dan terurai oleh mikroorganisme dalam waktu yang cukup singkat membuat plastik tersebut ramah lingkungan. Bahan yang digunakan dalam pembuatan bioplastik pada penelitian ini adalah pati jagung dan serat selulosa yang diekstrak dari kertas bekas menggunakan metode Asetilasi. Tujuan umum dari penelitian ini, adalah untuk mengetahui pengaruh penambahan serat selulosa pada sampel bioplastik dengan gliserol berperan sebagai pemlastis. Analisis bioplastik dilakukan dengan melakukan pengukuran uji kekuatan tarik, uji daya serap air, uji biodegradasi, dan pengamatan struktur menggunakan mikroskop optik. Hasil uji kuat tarik terbaik didapat pada penambahan 2 gram pulp selulosa, dengan nilai kuat tarik sebesar 1,65 MPa dan persentase nilai elongasi sampel 25%. Untuk uji daya serap air dengan persentase terkecil didapat pada penambahan 1 gram pulp dengan nilai 35,48%. Hasil uji biodegradasi terbaik adalah pada penambahan 1 gram dan 2 gram, dengan lama waktu degradasi 13 hari. Abstract Conventional plastics which are often used in everyday life cause the accumulation of plastic waste and cause environmental pollution problems because plastics are difficult to decompose by microorganisms. Bioplastic is one of the solutions used in reducing environmental pollution, its nature is easily degraded and decomposed by microorganisms in a fairly short time making the plastic environmentally friendly. The materials used in the manufacture of bioplastics in this study are corn starch and cellulose fibers which are extracted from wasted paper using the acetylation method. The general objective of this study was to determine the effect of adding cellulose fibers to bioplastic samples with glycerol acting as plasticizers. Bioplastic analysis is carried out by measuring the tensile strength test, water absorption test, biodegradation test, and observing the structure using an optical microscope. The best tensile strength test results were obtained in the addition of 2 grams of cellulose pulp, with a tensile strength value of 1.65 MPa and a percentage of the sample's elongation value of 25%. For the water absorption test with the smallest percentage was obtained the addition of 1 gram of pulp with a value of 35.48%. The best biodegradation test results were in the addition of 1 gram and 2 grams, with a degradation time of 13 days. &nbsp

Laser‐based powder bed fusion of metals (PBF‐LB/M) is used to build up configurable open‐porous structures—designed materials (DMs) — out of the nickel‐based superalloy Haynes 282. The main objective is to investigate process parameter influences on DM's morphological properties—relative density (RD), mean pore diameter (PD), mean strut diameter (SD), and surface ratio (SR). For the analysis of hatch distance, laser power, and scan speed—hence line and volume energy—effects a three‐level design of experiment (DoE) is utilized. The resulting process parameter combinations are applied to 77 samples; Multiple repetitions ensured statistical validity for the attained morphological information. The data points were used to elaborate equations for the properties based on the introduced process parameters. The identified relations were implemented into previously developed tolerance equations, which were afterward pre‐print‐predictable. These calculation‐based boundaries were assessed for their validity by comparing them to certain data points from five parameter sets. The RD equation was finally used to analyze the capability of reducing its tolerance width. Here, the formerly identified position‐dependent term was compensated by process parameter adaptions. The effects of the compensation on the other properties were also investigated.

Introduction: Autologous platelet-rich plasma (PRP) has been a growing trend in the field of medicine due to its broad range of application and is considered safe from bloodborne diseases. Furthermore, various studies have tried to optimize the use of autologous PRP through various preparation protocols, including PRP activation. However, most of the studies available have not evaluated the safety for intravenous delivery of PRP, especially autologous activated PRP (aaPRP). Therefore, this study aimed to evaluate the safety of intravenous delivery of aaPRP.Methods: Blood was drawn from each patient and aaPRP was isolated through calcium activation and light irradiation. Each aaPRP was administered intravenously to all patients. Adverse events were documented and analyzed.Results: Six hundred eleven patients participated in this study with a total of 4244 aaPRP therapies. Quality control of autologous aaPRP showed no platelets present after both calcium activation and light irradiation. No adverse events such as allergic reaction, infection, and coagulation problems were observed on all patients over the course of the study.Conclusion: Our results showed that intravenous administration of autologous aaPRP is safe even in patients with various pathological conditions.

Bioplastik masih memiliki kekurangan dibandingkan dengan plastik kemasan konvensional. Salah satunya adalah bioplastik tidak sekuat plastik kemasan konvensional. Salah satu cara dalam meningkatkan kekuatan mekanis bioplastik adalah dengan menambahkan pengisi dalam pembuatannya. Graphene oxide (GO) merupakan material pengisi yang mempunyai potensi menambah kekuatan mekanis dari bioplastik. Penelitian ini dilakukan untuk mengetahui pengaruh penambahan larutan GO yang disintesis dari tongkol jagung terhadap perubahan sifat fisis bioplastik berbahan dasar pati jagung. Pengujian bioplastik dilakukan dengan uji kuat tarik, uji daya serap air dan uji biodegrasi. Hasil penelitian menunjukkan bahwa penambahan larutan GO mempengaruhi kekuatan mekanik, daya serap air dan waktu biodegrasi bioplastik. Yaitu dengan nilai uji kuat tarik sebesar 1,20 MPa, sedangkan daya serap air 40% dan waktu degradasi sempurna 11 hari. Kata kunci: Bioplastik; Graphene Oxide; Kuat Tarik, daya serap air, Biodegradasi. Abstract Bioplastics still have disadvantages compared to conventional plastic packaging. One of them is that bioplastics are not as strong as conventional plastic packaging. One way to increase the mechanical strength of bioplastics is to add fillers in the manufacturing process. Graphene oxide (GO) is a filler that has the potential to increase the mechanical strength of bioplastics. This study was conducted to determine the effect of adding GO solution synthesized from corn cobs to changes in the physical properties of bioplastics based on corn starch. Bioplastic testing is carried out by tensile strength test, water absorption test and biodegradation test. The results showed that the addition of the GO solution affected the mechanical strength, water absorption capacity and the time of biodegradation of bioplastics. Namely, the tensile strength test value is 1.20 MPa, while the water absorption capacity is 40% and the complete degradation time is 11 days. Keywords: Bioplastics; Graphene Oxide; Tensile Strength; water absorption capacity; Biodegration. &nbsp

Timber utilisation and wood construction are fundamental components of Europe's strategy on progressing towards a sustainable bio-based economy. Both components require optimised strength grading procedures in Europe's sawmills. To further improve the current procedures, quality assessment and segregation of the raw material need to start already at the roundwood stage. Furthermore, the quality information should be made accessible throughout the production process to leverage the full potential for optimisation. This paper discusses the current state of research on combined log and board strength grading with a focus on the situation in Europe. It highlights limitations due to technology and current standardisation and identifies knowledge gaps and research opportunities. The European research project READiStrength (resource-efficient and data-driven integrated log and board strength grading) has been initiated to address these issues. Funder: ERANET Cofund Call "ForestValue – Innovating the forestbased bioeconomy"; Fachagentur Nachwachsende Rohstoffe e.V; Austrian Federal Ministry for Agriculture, Regions and Tourism; Microtec Srl GmbH; RemaSawco AB, Schilliger Bois SAS; Wiehag GmbH; Österreichische Bundesforste AG; Austrian Chamber of Agriculture;ISBN for host publication: 978-1-7138-4097-8; 978-1-7138-4111-1 READiStrength

Buildings taller than four storeys require the designer to mitigate consequences of unexpected events, e.g. terrorism or accidents, such that a disproportionate collapse can be avoided after initial damage. One approach to halt damage propagation is using structural robustness, i.e. by providing alternative load paths. For platform-type cross-laminated timber (CLT) buildings, catenary action as an alternative load path is not fully understood. The goal of the research presented in this paper is to numerically study catenary action as a resistance mechanism for floor panels after internal load-bearing wall removal, and to identify the governing parameters of this mechanism. For this purpose, a non-linear high-fidelity finite element model was constructed and calibrated against test results. All components and connections were individually modelled, to account for failure in the connectors and the timber components. A parameter study evaluated the impact of the floor span, the storey location, the connection type and the tie level on the development of catenary action. It was shown that in specific the connection, the storey location and the tie level had significant effects on catenary action. The results provide insight into how CLT floor systems can be detailed to trigger catenary action following internal wall removal. Funder: Bo Rydin Foundation;ISBN for host publication: 978-1-7138-4097-8; 978-1-7138-4111-1

This paper summarises the contemporary practices and implementations of existing codes and guidelines with respect to disproportionate collapse prevention as discussed in detail in Mpidi Bita et al. [1]. Focus is given on structural robustness, defined as the ideal method to decrease the probability of disproportionate collapse in buildings following an initial damage. The results from a global survey with 171 participants (mainly structural engineers) are presented. By comparing practices applied to different structural materials (steel, concrete and timber) and in different regions (Canada, USA, Europe, Australia/New Zealand), areas of improvements for the existing codes and guidelines as well as further research are identified. The results emphasise on the importance of including specific recommendations for structural robustness in building codes, applicable to high importance and high occupancy structures. A performance-based approach is preferable, rather than prescriptive requirements, for practical and economical solutions. In addition, the obtained responses highlight the need to further develop the existing indirect and direct methods for disproportionate collapse prevention and structural robustness to include material-specific considerations. ISBN for host publication: 978-1-7138-4097-8; 978-1-7138-4111-1

This paper presents radon flux profiles from four regions in Schleswig–Holstein (Northern Germany). Three of these regions are located over deep-rooted tectonic faults or salt diapirs and one is in an area without any tectonic or halokinetic activity, but with steep topography. Contrary to recently published studies on spatial patterns of soil radon gas concentration we measured flux of radon from soil into the atmosphere. All radon devices of each profile were deployed simultaneously to avoid inconsistencies due to strong diurnal variations of radon exhalation. To compare data from different seasons, values had to be normalized. Observed radon flux patterns are apparently related to the mineralogical composition of the Quaternary strata (particularly to the abundance of reddish granite and porphyry), and its grain size (with a flux maximum in well-sorted sand/silt). Minimum radon flux occurs above non-permeable, clay-rich soil layers. Small amounts of water content in the pore space increase radon flux, whereas excessive water content lessens it. Peak flux values, however, are observed over a deep-rooted fault system on the eastern side of Lake Plön, i.e., at the boundary of the Eastholstein Platform and the Eastholstein Trough. Furthermore, high radon flux values are observed in two regions associated with salt diapirism and near-surface halokinetic faults. These regions show frequent local radon flux maxima, which indicate that the uppermost strata above salt diapirs are very inhomogeneous. Deep-rooted increased permeability (effective radon flux depth) or just the boundaries between permeable and impermeable strata appear to concentrate radon flux. In summary, our radon flux profiles are in accordance with the published evidence of low radon concentrations in the “normal” soils of Schleswig–Holstein. However, very high values of radon flux are likely to occur at distinct locations near salt diapirism at depth, boundaries between permeable and impermeable strata, and finally at the tectonically active flanks of the North German Basin.

Tall buildings with a high occupancy need to resist disproportionate collapse caused by unforeseen exposures, e.g. terrorism or accidents. If a damage has occurred in a building, the damage propagation can be halted if the structure is robust, i.e. it provides alternative load paths (ALPs). The ALPs of platform-type cross-laminated timber buildings have not been studied in detail on the component level. The goals of this paper are thus to elicit which ALPs may develop on single storeys in a corner bay of a platform-type cross-laminated timber building, and to study how the various building components contribute to the ALPs. For this purpose, a non-linear quasi-static pushdown analysis was conducted in a finite element model of an 8-storey building after a wall removal. Friction, fastener failure, timber failure and large displacements were accounted for. Four different ALPs were identified at various storeys and their mechanisms were described. The results could be used to improve the capacity of the ALPs and make platform-type cross-laminated timber buildings more robust in the future. Funder: Bo Rydin Foundation;ISBN for host publication: 978-1-7138-4097-8; 978-1-7138-4111-1

Engineered wood products of today's construction industry require predictable mechanical properties of the used structural timber. At sawmills, automated strength grading is used to assess the stiffness and strength of sawn and dried timber boards. This process can be based on various technologies, e.g. surface scanning, dynamic excitation, flat-wise bending, which are used to derive so-called indicating properties, i.e. simplified numerical values. Heuristically derived statistical models can then be used to predict the stiffness and strength based on indicating properties. However, statistical strength grading can only exploit a small fraction of the potential strength of a single board, since it assesses the properties of a board in relation to its population. A growing number of sawmills in Sweden use computed tomography (CT) scanners to assess the incoming logs to optimise their positioning prior to sawing. CT scans provide high-quality data of the cross-sectional density distribution along the length of a log, which could also be used to derive continuum mechanical models of the yet unsawn boards and with that assess their mechanical properties. If the stiffness and strength of a virtual board can be predicted before it is sawn, then it could be pre-classified into a strength class or its specific use as a specific construction part could be predetermined already at the log stage, which would lead to a more efficient material usage. Additionally, the predictive power of the existing statistical strength grading processes could be improved for the final boards. The goals of this study were to i) derive 3D quasi-continuum and finite element (FE) models of CT scanned timber boards using different material laws for local stiffness based on measured density and ii) compare their capabilities for predicting stiffness and strength of the boards. The experimental material consisted of dried softwood boards (12% moisture content) of nominal cross-sectional dimensions 50x100mm with different lengths, scanned with a medical high-resolution CT scanner. The boards underwent an eigenfrequency measurement by dynamic excitation and were tested until failure in a four-point bending test, where both the local and global displacement were recorded. A previously developed algorithm was used to derive 3D quasi-continuum reconstructions from the CT scans and subsequently finite element (FE) models. The algorithm reconstructed the board geometry, pith, knots and local fibre directions (material coordinate system) on a volume grid of material points spaced 0.68mm apart. The stiffness tensor in each material point was made locally dependent on the measured density by different mathematical laws, e.g. constant, linear or power laws. Furthermore, material laws which scaled the stiffness tensor based on the ratio between the simulated and measured eigenfrequency were tested for comparison. The bending stiffness profile was calculated for each board along its length and different indicating properties for predicting stiffness and strength were derived and compared with respect to the experimental results. With the FE model, strain distributions in the cross-sections were studied and local stress states around the experimentally observed points of initial failure were investigated to determine whether similar dominant failure stress states existed among boards. The results showed high coefficients of determination between predicted stiffness and strength for material laws based on power laws and low values for linear laws. Nevertheless, the four-point bending tests only provided point-wise data (mid points) that could be used to validate the numerical model. It is therefore recommended to use field-based evaluations in the future, e.g. the surface strain obtained with DIC under four-point testing. ReadIStrength

Engineered wood products of today's construction industry require predictable mechanical properties of the used structural timber. At sawmills, automated strength grading is used to assess the stiffness and strength of sawn and dried timber boards. This process can be based on various technologies, e.g. surface scanning, dynamic excitation, flat-wise bending, which are used to derive so-called indicating properties, i.e. simplified numerical values. Heuristically derived statistical models can then be used to predict the stiffness and strength based on indicating properties. However, statistical strength grading can only exploit a small fraction of the potential strength of a single board, since it assesses the properties of a board in relation to its population. A growing number of sawmills in Sweden use computed tomography (CT) scanners to assess the incoming logs to optimise their positioning prior to sawing. CT scans provide high-quality data of the cross-sectional density distribution along the length of a log, which could also be used to derive continuum mechanical models of the yet unsawn boards and with that assess their mechanical properties. If the stiffness and strength of a virtual board can be predicted before it is sawn, then it could be pre-classified into a strength class or its specific use as a specific construction part could be predetermined already at the log stage, which would lead to a more efficient material usage. Additionally, the predictive power of the existing statistical strength grading processes could be improved for the final boards. The goals of this study were to i) derive 3D quasi-continuum and finite element (FE) models of CT scanned timber boards using different material laws for local stiffness based on measured density and ii) compare their capabilities for predicting stiffness and strength of the boards. The experimental material consisted of dried softwood boards (12% moisture content) of nominal cross-sectional dimensions 50x100mm with different lengths, scanned with a medical high-resolution CT scanner. The boards underwent an eigenfrequency measurement by dynamic excitation and were tested until failure in a four-point bending test, where both the local and global displacement were recorded. A previously developed algorithm was used to derive 3D quasi-continuum reconstructions from the CT scans and subsequently finite element (FE) models. The algorithm reconstructed the board geometry, pith, knots and local fibre directions (material coordinate system) on a volume grid of material points spaced 0.68mm apart. The stiffness tensor in each material point was made locally dependent on the measured density by different mathematical laws, e.g. constant, linear or power laws. Furthermore, material laws which scaled the stiffness tensor based on the ratio between the simulated and measured eigenfrequency were tested for comparison. The bending stiffness profile was calculated for each board along its length and different indicating properties for predicting stiffness and strength were derived and compared with respect to the experimental results. With the FE model, strain distributions in the cross-sections were studied and local stress states around the experimentally observed points of initial failure were investigated to determine whether similar dominant failure stress states existed among boards. The results showed high coefficients of determination between predicted stiffness and strength for material laws based on power laws and low values for linear laws. Nevertheless, the four-point bending tests only provided point-wise data (mid points) that could be used to validate the numerical model. It is therefore recommended to use field-based evaluations in the future, e.g. the surface strain obtained with DIC under four-point testing. ReadIStrength

A procedure is presented to generate 3D FE models of timber boards based on CT scans. Theboards were tested in four-point bending tests until failure and the local displacement in the pure bendingzone was recorded. The CT scans were treated as 3D images and image processing methods were usedto reconstruct the board, the knots and the pith. A new procedure to reconstruct the fibre deviationsaround knots by accounting for image gradient information was used. A quadratic tetrahedral mesh wasgenerated for the region of the board which was under pure bending in the tests. The fibre directions andthe stiffness tensor, scaled by the local density, were transferred into each integration point of the meshand the bending test was replicated. Preliminary results show that the procedure is able to realisticallypredict the observed local stiffness of the boards. Further development of the procedure is required toaccount for dead knots and to extend the procedure for indicating strength and predicting failure. ReadiStrength

Telah dilakukan penelitian tentang visualisasi fenomena kombinasi difraksi dan interferensni pada celah ganda dengan tujuan menerapkan metode secant untuk memperoleh solusi jarak terang pusat ke terang dengan intensitas tertentu dan memperoleh grafik 2 dimensi dari distribusi intensitas cahaya. Solusi jarak terang pusat (intensitas maksimum) ke terang dengan intensitas tertentu padakasuskombinasi difraksi dan interferensi pada celah ganda diperoleh dengan mencari akar-akar persamaan intensitascahayanya.Dari hasil perhitungan grafis dan komputasi diperoleh solusi jarak terang pusat ke terang dengan intensitas tertentu.Pada nilai perbandingan 0.6I0, metode grafis dengan rentang nilai x dari 0.00877 sampai 0.0088 diperoleh nilai jarak terang pusat ke terang dengan intensitas tertentu sebesar 0.008781 mm. Sedangkan pada metode komputasi dengan nilai tebakan 0.005 dan 0.264 diperoleh nilai jarak 0.00878129 mm. Dari dua variasi yang digunakandapat dilihat bahwa pada variasi panjang gelombang, 500 nm, 550 nm, dan 600 nm diperoleh interval pita terang pusat berturut-turut dari -0.0094392 mm sampai 0.00943919 mm, -0.0103831 mm sampai 0.01038311 mm, dan-0.011327 mm sampai 0.01132703 mm. Kemudian pada variasi jarak celah ke layar 500 mm, 550 mm, dan 600 mm diperoleh nilai interval pita terang berturut-turut dari -0.0103831mm sampai 0.01038311 mm, -0.01142142 mm sampai 0.01142142 mm, dan -0.0124597 mm sampai 0.01245973 mm.Katakunci: Difraksi; interferensi; Celah Ganda; Intensitas, Secant Abstract Research on the visualization of diffraction and interference combination phenomena on double slits has been carried out to apply the secant method for determining the solution of the maximum distance intensity to bright with the certain intensity and obtaining a two graph of the light intensity distribution. The solution of the maximum distance intensity to bright with a certain intensity is obtained by looking for the roots of the light intensity equation.From the result of calculationgraphical and computationally have gotten the solution of the maximum distance intensity to bright with a certain intensity. On the comparison value 0.6I0, a graph method with the interval from 0.00877 to 0.0088 is gotten the maximum distance intensity luminous with a certain intensity of 0.008781 mm. Meanwhile, on computational methods with the guessed value, 0.005 to 0.264 is reached distance value 0.00878129 mm. From two variation used, can be viewed that on wavelength variation 500 nm, 550 nm, 600 nm, are obtained a central light band interval successively from -0.0094392 mm to 0.00943919 mm, -0.0103831 mm to 0.01038311 mm, and 0.011327 mm to 0.01132703 mm. Then in the variation of the gap distance to the screen of500 mm, 550 mm, and 600 mm, the values of thebright band intervals are obtained from -0.0103831 mmto 0.01038311 mm, -0.01142142 mm to0.01142142mm, and -0.0124597 mm to 0.01245973mm.Keywords: Diffraction; Interference; double slits; intensity; and secant.

Penelitian tentang kajian awal sifat optik Graphene Oxide (GO) berbahan dasar arang sekam padi dengan metode Liquid Phase Exfoliation (LPE) menggunakan alat bantu blender dan Ultrasonic Cleaner telah dilakukan. Tujuan penelitian ini adalah mengetahui pengaruh variasi waktu sintesis GO menggunakan blender, ultrasonifikasi, dan blender yang dilanjutkan dengan ultrasonifikasi pada sifat optik GO, berdasarkan pada hasil karakterisasi UV-Vis. Dengan menggunakan alat bantu tersebut dilakukan variasi waktu 1 jam, 2 jam, dan 3 jam. Larutan didiamkan semalam, diambil bagian yang terangkat ke permukaannya dan dipisahkan. Kemudian bagian yang dipisahkan tersebut diencerkan dengan menggunakan aquades. Hasil tersebut dikarakterisasi menggunakan Spektrometer UV-Vis untuk mendapatkan spektrum serapannya. Berdasarkan hasil analisis spektrum dari ketiga perlakuan diperoleh jangkauan spektrum berada dalam range 200 nm sampai 400 nm. Nilai puncak serapan maksimum pada perlakuan blender 1 jam, 2 jam dan 3 jam secara berturut – turut adalah 3,319; 3,333dan 3,983 pada masing – masing panjang gelombang 223 nm; 222 nm dan 223 nm. Nilai puncak serapan maksimum pada perlakuan ultrasonifikasi 1 jam, jam dan 3 jam secara berturut – turut adalah 2,466; 2,115 dan 1,877 pada masing – masing panjang gelombang 223 nm; 223 nm dan 224 nm. Nilai puncak serapan maksimum pada perlakuan blender yang dilanjutkan dengan ultrasonifikasi 1 jam, 2 jam dan 3 jam secara berturut – turut adalah 2,777; 1,838; dan 1,961 pada masing – masing panjang gelombang 224 nm; 223 nm dan 224 nm. Berdasarkan nilai puncak serapan dan rentang panjang gelombang yang diperoleh dari hasil karakterisasi spektrometer UV-Vis, dapat disimpulkan bahwa material GO berhasil disintesis dalam penelitian ini. Dari hasil perbandingan spektrum ketiga perlakuan di atas, sintesis GO dengan metode LPE dengan alat bantu blender menghasilkan GO dengan konsentrasi yang paling tinggi dan waktu mempengaruhi jumlah konsenterasi GO yang dihasilkan.Kata kunci: GO; LPE, blender; ultrasonifikasi; blender-ultrasonifikasi. AbstractA preliminary study on the optical properties of Graphene Oxide (GO) from rice husk charcoal with the Liquid Phase Exfoliation (LPE) method using a blender and ultrasonic cleaner treatment has been done. The purpose of this research is to determine the influence of the time variation of GO synthesis using a blender, ultrasonication, and blender followed by ultrasonication on the optical properties of GO, based on the results of UV-Vis characterization. With the use of the treatment tools, we made 1 hour, 2 hours, and 3 hours’ time variations respectively. The solution was left overnight, then the raised portion on the surface was separated from the solution. The separated parts were diluted using equates and then characterized using the UV-Vis spectrometer to obtain its absorption spectrum. Based on the results of the spectrum analysis of the three treatments, spectrum coverage is obtained in the range of 200 nm to 400 nm. The maximum absorption coefficients from the 1 – hour, 2 – hour, and 3 – hour blender treatment were 3.319; 3.333, and 3.983 at 223 nm, 222 nm, and 223 nm respectively. The corresponding values from ultrasonication treatment were 2.466; 2.115 and 1.877 at 223 nm, 223 nm, and 224 nm respectively, and those from the blender treatment followed by ultrasonication were 2.777; 1.838 and 1.961 at 224 nm, 223 nm, and 224 nm respectively. Based on the absorption coefficients and the wavelength range obtained from UV-Vis spectrometer characterization results, it can be concluded that the GO material was successfully synthesized in this research. From the comparisons of the three treatments, GO synthesized using the LPE method with the blender treatment yields GO with the highest concentration, and time affects the number of GO concentrations produced.Keywords: GO, LPE, Blender, Ultrasonication, Blender- ultrasonication.

Die vorliegende Studie hat bestätigt, dass Notfallereignisse im zahnärztlichen Berufsalltag zwar nicht die Regel sind, allerdings muss ein Zahnarzt entsprechend unserer Datenerhebung bei 30-jähriger Berufstätigkeit nach der Statistik in diesem Zeitraum mit 12 bis 15 Notfällen rechnen. Die traumatisierende Wirkung eines Notfallereignisses, auf das die Praxis nicht vorbereitet ist, sollte dabei nicht unterschätzt werden. Das Wissen auf Notfallsituationen gut vorbereitet zu sein, verschafft dabei sowohl dem Behandler als auch dem Praxisteam Souveränität. Eine professionelle Reaktion auf ein Notfallereignis erhält auch das Vertrauen des betroffenen Patienten sowie anderer Patienten in der Praxis, die selbst nicht unmittelbar vom Notfall betroffen sind. In jeder der befragten Praxen ist eine gewisse Notfallausstattung vorhanden und in fast allen dieser Praxen wird ein - wenn auch teils nur praxisinternes - Training durchgeführt. Die teils von den Empfehlungen der vorliegenden Arbeit divergierende und unvollständige Notfallausstattung zeigt jedoch, dass bei der Vorbereitung auf Notfallereignisse noch erhebliches Verbesserungspotential besteht. Bei der Datenerhebung für die Umfrage war das teils zurückhaltende Antwortverhalten der Zahnarztpraxen problematisch. Die Umfrage hat auch gezeigt, dass die konventionelle Methode mit Papierfragebögen jedenfalls bei der hier befragten Zielgruppe immer noch wesentlich ergebnisreicher ist als eine online-Befragung. Die Hemmung, einen zugesandten oder gar ausgehändigten Fragebogen unbearbeitet zu lassen, erscheint größer als die Versuchung, ihn einfach wegzuklicken. Für vergleichbare Erhebungen empfiehlt sich daher bei dieser Zielgruppe immer noch die konventionelle, analoge Methode. Die Umfrage hat gezeigt, dass eine ganze Reihe der Medikamente und Hilfsmittel, die für Notfälle notwendig sind, bei den Befragten auch vorgehalten werden. Allerdings besteht in manchem Notfallkoffer auch noch Ergänzungsbedarf. Hier gilt es, das Problembewusstsein der Behandler zu schärfen und die Notfallausstattung zu ergänzen. Überlegungen, sich aufgrund eines wenig invasiven Behandlungsspektrums nur mit einer reduzierten Notfallausstattung zufrieden zu geben, erscheinen wenig sinnvoll, weil sämtliche gängig mögliche Notfallsituationen auch im Rahmen derartiger Behandlungen auftreten können. Auch sollten Notfallsituationen ernsthaft trainiert werden. Die beste Ausstattung ist sicherlich nur wenig hilfreich, wenn im Ernstfall niemand weiß, wo sich was befindet und wie es richtig eingesetzt wird. Bisweilen ist die Schulung durch einen externen Dozenten didaktisch sicherlich effizienter als die durch den eigenen Praxisinhaber oder einen anderen Mitarbeiter. Die genannten Empfehlungen dieser Arbeit dienen als Ansatz, die ambulante zahnärztliche Versorgung und Patientensicherheit weiter zu verbessern. Wünschenswert wäre es, wenn langfristig komplett zusammengestellte und übersichtlich gestaltete Notfallsets von der Industrie in den Handel gebracht werden könnten, die der einzelnen Praxis das zeitintensive Zusammenstellen ersparen würde. Eine langfristige Vision wäre, dass sich der Behandler via Internet über ein im Notfallkoffer eingebautes Headset sich direkt mit einem erfahrenen Notfallmediziner in Verbindung setzen kann. Dieser wüsste dann genau über den Inhalt des entsprechenden Notfallkoffers Bescheid und könnte den Zahnarzt in der für ihn immer ungewohnten und stressigen Situation beratend unterstützen.

Without additional design considerations, such as structural robustness, the failure of a building’s structural element can develop into a progressive and/or disproportionate collapse. The existing requirements given in international guidelines for preventing disproportionate collapse are generally not practical and uneconomic when applied to multi-storey cross-laminated timber (CLT) buildings in platform-type construction. This paper summarises recent research and improved approaches developed to meet structural robustness for such buildings. To ensure alternative load-paths using simplified linear elastic analytical procedures, an improved method using engineering mechanics was derived for CLT buildings in platform-type construction to aid in quantifying connection tie forces between structural components. Using advanced nonlinear dynamic analyses, the behaviour of two case-study buildings under element removal scenarios are studied: i) 12-storey with CLT floor and wall system; and ii) 9-storey flat-plate CLT floor system point-supported on glulam columns. Finally, in a nonlinear pushdown analysis of a platform CLT bay to characterise the resistance mechanism of the floor and wall panels, four different alternative load-paths are evaluated. The presented findings can support the design of multi-storey CLT buildings in platform-type construction to ensure structural robustness. Godkänd;2021;Nivå 0;2021-05-28 (alebob)

Multi-storey cross-laminated timber (CLT) buildings are a comparatively recent construction type. Knowledge concerning the performance of CLT buildings regarding the prevention of disproportionate collapse after unforeseeable events (e.g. accidents or acts of terrorism) is not as refined as that for concrete and steel buildings. In particular, alternative load paths (ALPs) after the removal of a wall panel in platform-framed variants have not yet been studied in detail. The goal of this work was therefore to study ALPs in CLT buildings. An eight-storey bay of an existing building was evaluated by conducting a non-linear static pushdown analysis in a finite element analysis on three representative storeys. The analyses accounted for single fastener behaviour, timber crushing, friction, brittle failure and large deformations. The force–deformation behaviours elicited under the pushdown analyses were subsequently inserted in a simplified dynamic model to evaluate the transient response of the entire bay. Four ALPs were identified in this case – shear resistance in the floor panels, arching action of the walls, catenary action in the floor panels and hanging action from the roof. The dynamic analysis did not show a collapse, unless the inter-compartment stiffness was significantly reduced. The resistance mechanisms are described in this paper, which may provide information for improved building design. Validerad;2020;Nivå 2;2020-04-22 (alebob)

A method is presented for reconstructing the geometry, the pith, the knots and the local fibre orientations in timber boards, based on X-ray computed tomography scans. The local fibre deviations around knots were found by a new algorithm, based on image analysis. The experimental data comprised tomography scans, eigenfrequency measurements and four-point bending tests of 20 Norway spruce boards. 3D and 1D finite element models of the pure bending zone of the bending tests were created, accounting for the exact board geometry and the reconstructed fibre deviations. A purely density based, a purely eigenfrequency based, and a mixed constitutive law were compared. Model estimations showed a high coefficient of determination (R2) for global modulus of elasticity (MoE) (R2⩽0.93), local MoE (R2⩽0.87), bending strength (R2⩽0.83), and the location of initial failure. Constitutive laws accounting for eigenfrequency showed the most accurate results. In the future, adapting the method for logs could enable analyses of boards before sawing. Validerad;2021;Nivå 2;2021-11-22 (beamah);Funder: READiStrength project READiStrength

Abstract. Longitudinal panels include several thousand participants and variables. Traditionally, psychologists analyze only a few variables – partly because common unregularized linear models perform poorly when the number of variables ( p) approaches the number of observations ( N). Predictive modeling methods can be used when N [Formula: see text] p situations arise in psychological research. We illustrate these techniques on exemplary variables from the German GESIS Panel, while describing the choice of preprocessing, model classes, resampling techniques, hyperparameter tuning, and performance measures. In analyses with about 2,000 subjects and variables each, we predict panelists’ gender, sick days, an evaluation of US President Trump, income, life satisfaction, and sleep satisfaction. Elastic net and random forest models were compared to dummy predictions in benchmark experiments. While good performance was achieved, the linear elastic net performed similar to the nonlinear random forest. Elastic nets were refitted to extract the ten most important predictors. Their interpretation validates our approach, and further modeling options are discussed. Code can be found at https://osf.io/zpse3/

Multi-storey buildings require mitigation of consequences of unexpected or accidental events, to prevent disproportionate collapse after an initial damage. Cross-laminated timber (CLT) in platform-type construction is increasingly used for multi-storey buildings, however, the collapse behaviour and alternative load paths (ALPs) are not fully understood. A 3D non-linear component-based finite element model was developed for a platform-type CLT floor system to study the ALPs after an internal wall loss, in a pushdown analysis. The model, which accounted for connection failure, timber crushing and large displacements, was calibrated to experimental results and then adapted for boundary conditions corresponding to typical residential and office buildings. Subsequently, five parameters (floor span, connection type, vertical location of the floor, tying level, horizontal wall stiffness) were varied, to study their effects on the ALPs in 80 models. The results showed that three ALPs occurred, of which catenary action was the most dominant. Collapse resistance was mainly affected by the floor span, followed by the axial strength, stiffness and ductility of the floor-to-floor connection, the weight of the level above and the floor panel thickness. This study provides an approach to model ALPs in a platform-type CLT floor system to design disproportionate collapse resistant multi-storey CLT buildings. Validerad;2021;Nivå 2;2021-05-19 (beamah)

Component production via laser‐based powder bed fusion of metals (PBF‐LB/M) is becoming reality for multiple applications. Especially for sophisticated parts, as in case of gas turbines, assurance of repeatable properties involves control of process and machine parameters. PBF‐LB/M is used to build configurable open‐porous structures—designed materials (DMs)—out of the high temperature superalloy Haynes 282 with relative densities from 35% to 65%. The objective is investigating positioning influence and process stability based on their relative densities in discrete scan fields and build jobs. As DMs made from Haynes 282 are not yet scientifically investigated, first the process boundaries are identified. The used PBF‐LB/M machine—EOS M 400‐4—works with four lasers in four quadrants—a quadrant benchmarking is carried out. The experiment is repeated in a second build job. Scatter is identified in quadrant and build job benchmarking. A further aspect under investigation is positioning within laser quadrants. However, keeping laser and parameter combinations constant, sample locations are assessed. A relative density dependency on the laser deflection angle—as a positional measure—is observed. The results of positioning influence and scatter are used to formulate a tolerance equation for relative densities of DMs.