Height Variation Research Articles

Evaluating the Use of Seasonal Surface Displacements and Time‐Variable Gravity to Constrain the Interior of Mars

AbstractThe mass transport of volatiles on Mars represents a seasonally changing load on the surface of the planet. Like on Earth, as mass is redistributed across the planet, the surface responds in a complex manner becoming displaced downwards or upwards. The magnitude and extent of displacement depend on the properties of the load and mechanical properties of the planetary interior. Based on new estimates of the height variation of the seasonal polar caps (SPCs), we predict local surface displacements of up to tens of millimeters with a strong degree 1 signal throughout the Martian year. The long‐wavelength portion of the displacement is potentially observable, with a magnitude of a few millimeters, located away from the SPC where one could realistically measure it with a landed or orbital mission. We also model the direct contribution of this process to observable time variable gravity, where we find the zonal coefficients to be in line with previous measurements, although with a smaller magnitude. Future measurements of this displacement could be used to help elucidate the composition of the interior of Mars using this process as a probe into the Martian interior. Furthermore, more refined measurements of time‐variable gravity would be a powerful tool in constraining the pole‐to‐pole volatile cycle present on Mars.

Pressing Strength of Plastic Bottle Couch as a Form of Waste Management Innovation in UMKM Sobotik

Abstract In general, people burn plastic waste openly because they do not know the impact it can cause. Couch from plastic bottles one of the effective alternative innovations. The objective of this study was to determine the strength of the plastic bottle couch from the UMKM Sobotik couch product as the effort to develop creativity in utilizing plastic waste. Plastic bottles that have been glued according to the size and shape designed are given a load (load cell) at the center point of the test object. The shortening of the specimen during compression was observed by two linear variable differential transformers (LVDT) which were placed on the top of the flat surface on different sides of the specimen. The difference in the compressive strength of the plastic bottle couch specimen was based on the variable height of the plastic bottles making up the couch, the cross-sectional shape of the couch, and the position of the fastener (duct tape). There are three types of plastic bottles that make up the couch for this test, namely 1500 ml, 600 ml and 330 ml with the height of each bottle being 290 mm, 226 mm and 170 mm respectively. The results of the compressive load test on the plastic bottles that make up the couch ranged from 241 kgf-621 kgf. The strength of the couch is influenced by the number of adhesives, the location of the adhesive and the shape of the couch. The specimen with the smallest rigidity is a rectangular cross section. Round cross sections tend to have advantages over other cross sections. Due to the pressure received by the test object can be spread evenly throughout the radius of the test object. For a square cross section, there is a cross section that is shorter than the other parts, resulting in non-uniformity of the load received by the parts of the cross section, so that the round shape has great strength.

PENGARUH VARIASI TINGGI SUDU TURBIN DARI TINGGI BASIN TERHADAP DAYA DAN EFISIENSI TURBIN VORTEX

Electrical energy is a very important need for human life in various aspects, both on a large and small scale. One of the efforts to reduce the use of fossil fuels is to use natural resources that are not limited and can be renewed. Micro Hydro Power Plant (MHP) is an alternative source of electricity for the community, one of which is a vortex turbine. The vortex turbine is one type of micro hydro turbine that utilizes a whirlpool as a blade drive. This study examines the effect of blade height variations of 25%, 30%, and 35% of the basin height on power and efficiency. The results showed that the largest turbine power at 25% blade height variation from the basin height with a discharge of 0.009 m3/s was 3.294 Watt with an efficiency of 51.10%. The largest turbine power at an angle variation of 30% of the basin height with a discharge of 0.009 m3/s is 3.364 Watt with an efficiency of 50.66%. The largest turbine power at an angle variation of 35% of the basin height with a discharge of 0.009 m3/s is 4.062 Watt with an efficiency of 62.35%. Turbine power based on two-way anova analysis shows that between variations in turbine height and flow discharge have a significant effect on the turbine power produced and turbine efficiency based on two-way anova analysis shows that between variations in turbine height and flow discharge have a significant effect on the turbine efficiency produced.

Optimization of Hanger Spacing of Steel Arch Bridges Using Dynamic Loads

Bridges are basic infrastructure that must be met to create regional connectivity in Indonesia. One type of bridge that is often used is a curved bridge, which has the advantages of high strength, attractiveness, aesthetics and economy. In order to accelerate the development of bridge infrastructure, an efficient innovation in curved bridge design is needed. The development of curved bridge structures to achieve efficient designs has received much attention in several decades. However, researchers have only focused on optimising the geometry variation of the arch height. Therefore, the aim of this research is to innovate the optimisation of the hanger spacing on the arch bridge structure. In order to obtain optimal results, a bridge model is carried out by varying the hanger spacing of the centre model with a hanger spacing ratio of (1.3 - 1.1 - 0.9 - 0.7), a flat model with a hanger spacing ratio of (1 - 1 - 1 - 1) and an edge model with a hanger spacing ratio of (0.7 - 0.9 - 1.1 - 1.3), so that from the three models, the effect of hanger location on three conditions is obtained. Each model is modelled in the SAP2000 software and given a bridge service load to obtain the internal forces and deflections that occur. The output of the internal force and deflection is then analysed to determine the effect of the location of the bridge service hanger. The serviceability of the bridge is also analysed by calculating the ratio between the weight of the bridge and the deflection that occurs. The results of the analysis show that the location of the hanger affects the performance of the arch bridge structure. The centre model bridge design produces the most efficient structural performance in resisting the compressive axial forces and moments that occur, and produces the least deflection. Meanwhile, the edge model will provide the most efficient structural performance in resisting tensile axial forces. By referring to the results of the bridge weight to deflection ratio analysis, it can be concluded that the centre model produces the most efficient structural design when compared to other curved bridge models.

EFEKTIVITAS TIGA BAHAN ORGANIK TERHADAP SERANGAN HAMA, PERTUMBUHAN DAN PRODUKSI SAWI

Pakcoy mustard greens are a type of rain-resistant vegetable. Pakcoy has green leaves with high nutritional content and economic value. One of the efforts that can be made to increase plant production is by providing fertilizer. Fertilization is carried out in order to meet the nutrient needs of plants, so that they can provide high yields, especially using organic fertilizer so that you can use waste as fertilizer. One type of recycled waste that can be used as organic fertilizer is egg shells, tea dregs and banana peels, each of which contains elements that are good for cultivation. Apart from that, pak choy mustard plants have the main problem that causes damage to pak choy, namely destructive pests that eat pak choy leaves such as plutella caterpillars, tritip caterpillars, armyworms, aphids (Aphids), cabbage spanner caterpillars. This research will be carried out from October to December 2023 at the UNISKA Integrated Field Laboratory. With a height of 67 meters above sea level, the temperature is 31.2◦C, humidity is 62.3% and soil pH is 6. Based on the research results, it shows that there is a very real influ.ence on the observed variables of plant height and number of leaves at the age of 14, 21 and 28 DAP, and it has an effect significant in root length at 28 days after planting. Fresh weight, dry weight, and armyworm pest attacks were lowest at P7.

Trends of extreme waves around Hainan Island during typhoon processes

Extreme waves mostly occur during typhoon processes in China Seas. This study statistically shows the trends of extreme wave height over the past several decades around Hainan Island, based on the reconstruction of historical wave processes during the typhoon events from 1949 to 2022. Totally 807 events in the tropical cyclone (TC) best track datasets are numerically simulated by the widely used wave model SWAN. The driving wind fields are reconstructed as a combination of an empirical cyclone wind model with the reanalysis wind field data, in order to better simulate waves near cyclone centers with higher spatial resolution. Based on the reconstructed wave data, the spatial distribution of wave characteristics around Hainan Island has been provided. The Mann-Kendall test shows a descending trend of extreme wave height in the southeast side of Hainan Island, where the maximum descending rate could reach up to 5 cm/yr. The influence of the long-term trend on the design extreme wave height is also discussed. Comparing to the variation of the design extreme wave height with sampling period, the long-term trend is also a significant impact factor.

Agro-morphological Growth Response of Acha (FONIO) (Digitaria exilis and Digitaria iburua [Kippist] Stapf.) Exposed to Colchicine: Germination, Plant Height and Leaf Number

Acha (Fonio) Digitaria sp. is a valuable cereal crop widely cultivated in several African countries. The genetic improvement of Acha through induced mutagenesis has gained attention for enhancing desirable traits. Colchicine, a mitotic inhibitor, is commonly used to induce polyploidy, which can lead to alterations in plant characteristics. This study aimed to investigate the effects of colchicine treatment on germination, plant height, and leaf count of two Acha species. Seeds from two Digitaria species, Digitaria exilis, and Digitaria iburua, were subjected to colchicine treatment using different concentrations (0.05, 0.10, 0.15, and 0.20g/dL). The control group was treated with distilled water. Germination rates were assessed by measuring the percentage of seeds that successfully sprouted. Plant height and leaf number were measured at maturity and analyzed using ANOVA on SPSS Version 26. The results indicated that colchicine treatment significantly affected germination, plant height, and leaf number in both Digitaria species. Germination rates varied depending on the concentration, with lower germination observed at higher concentrations (70.70% and 74.3% for 0.20g/dL treatment in both species). In terms of plant height, colchicine-treated Acha plants exhibited significant differences compared to the control group. The majority of treated plants showed increased growth (57.00 cm to 60.70 cm in D. exilis and 114.10 to 122.40 cm in D. iburua) compared to the control. Variability in plant height was observed among the treated plants, suggesting that colchicine-induced polyploidy had varying effects on height across different genotypes. Similarly, the number of leaves was affected by colchicine treatment. Treated plants exhibited an increase in leaf number (56.70 to 60.7 for D exilis and 32.60 to 36.30 for D. iburua), compared to the control group (49.7 and 29.7 respectively). This variability suggests that colchicine-induced polyploidy may have influenced leaf development and growth patterns in Acha. Colchicine treatment had significant effects on germination, plant height, and leaf count in both varieties of Acha. The results suggest that colchicine-induced polyploidy can alter these plant characteristics. These findings provide insights into the potential use of colchicine treatment for inducing desirable traits in Acha through polyploidization, which may have implications for crop improvement and breeding programs. Further research is warranted to explore the underlying mechanisms and assess the impact of these alterations on overall agronomic performance and yield potential.

Spatio-temporal variation of aerosol loading and planetary boundary layer height before, during and after COVID-19 lockdown over the major cities in India

Spatio-temporal variation of aerosol loading and planetary boundary layer height before, during and after COVID-19 lockdown over the major cities in India

Culm Morphological Analysis in Moso Bamboo Reveals the Negative Regulation of Internode Diameter and Thickness by Monthly Precipitation.

The neglect of Moso bamboo's phenotype variations hinders its broader utilization, despite its high economic value globally. Thus, this study investigated the morphological variations of 16 Moso bamboo populations. The analysis revealed the culm heights ranging from 9.67 m to 17.5 m, with average heights under the first branch ranging from 4.91 m to 7.67 m. The total internode numbers under the first branch varied from 17 to 36, with internode lengths spanning 2.9 cm to 46.4 cm, diameters ranging from 5.10 cm to 17.2 cm, and wall thicknesses from 3.20 mm to 33.3 mm, indicating distinct attributes among the populations. Furthermore, strong positive correlations were observed between the internode diameter, thickness, length, and volume. The coefficient of variation of height under the first branch showed strong positive correlations with several parameters, indicating variability in their contribution to the total culm height. A regression analysis revealed patterns of covariation among the culm parameters, highlighting their influence on the culm height and structural characteristics. Both the diameter and thickness significantly contribute to the internode volume and culm height, and the culm parameters tend to either increase or decrease together, influencing the culm height. Moreover, this study also identified a significant negative correlation between monthly precipitation and the internode diameter and thickness, especially during December and January, impacting the primary thickening growth and, consequently, the internode size.

RESPON TANAMAN PAKCOY (Brassica rapa L.) TERHADAP PEMBERIAN SERBUK KAYU DAN PUPUK PETRORGANIK

One effort that can be made to improve soil fertility is by providing rich and petroganic powders. This research aims to determine the growth response of pakcoy plants to a combination of wood dust and petrorganic fertilizer treatments. This research was carried out from April to July 2023 in Sumber Rejeki Village, Merauke. This research used a randomized block design. The variables observed were plant height, number of leaves, leaf length, leaf width, and wet weight. The results of the research showed that the combination of sawdust and petroganic treatments had a different effect on each variable of pakcoy plant growth. The highest treatment on the plant height variable was obtained in the treatment without rich powder + 1 t.ha-1 petroganic fertilizer, the number of leaves in the sawdust treatment was 20 t.ha-1 + 3 t.ha-1 petroganic fertilizer, the leaf length was found in the treatment without wood dust + petroganic fertilizer 1 t.ha-1, leaf width was found in the treatment without sawdust + petroganic fertilizer 1 t.ha-1 and wet weight was found in the wood powder treatment 10 t.ha-1 + petroganic fertilizer 3 t.ha-1.

Variation of winter wheat plant height depending on ecotype and meteorological conditions

Variation of winter wheat plant height depending on ecotype and meteorological conditions

Mathematical explanations for knee osteotomies: "Dear engineer, how would you explain it in a simple way?"

Knee osteotomies are effective procedures to treat different deformities and to redistribute the load at the joint level, reducing the risk of wear and, consequently, the need for invasive procedures. Particularly, knee osteotomies are effective in treating early arthritis related to knee deformities in young and active patients with high functional demands, with excellent long-term results. Precise mathematical calculations are imperative during the preoperative phase to achieve tailored and accurate corrections for each patient and avoid complications, but sometimes those formulas are challenging to comprehend and apply. Four specific questions regarding controversial topics (planning methods, patellar height, tibial slope, and limb length variation) were formulated. An electronic search was performed on PubMed and Cochrane Library to find articles containing detailed mathematical or trigonometrical explanations. A team of orthopedic surgeons and an engineer summarized the available Literature and mathematical rules, with a final clear mathematical explanation given by the engineer. Wherever the explanation was not available in Literature, it was postulated by the same engineer. After the exclusion process, five studies were analyzed. For three questions, no studies were found that provided mathematical analyses or explanations. Through independent calculations, it was demonstrated why Dugdale's method underestimates the correction angle compared to Miniaci's method, and it was shown that the variation in patellar height after osteotomy can be predicted using simple formulas. The five included studies examine postoperative variations in limb length and tibial slope, providing formulas applicable in preoperative planning. New formulas were independently computed, using the planned correction angle and preoperatively obtained measurements to predict the studied variations. There is a strict connection among surgery, planning, and mathematics formulas in knee osteotomies. The aim of this study was to analyze the current literature and provide mathematical and trigonometric explanations to important controversial topics in knee osteotomies. Simple and easy applicable formulas are provided to enhance the accuracy and outcomes of this surgical procedure.

Assessing the engineering, environmental and economic aspects of repowering onshore wind energy

As onshore wind farms approach the end of their life, critical decisions about their future become imperative. Wind turbine repowering projects encounter multifaceted challenges across economic, engineering, environmental, and social domains. This study critically examines the state of the art in onshore wind repowering on a global scale. The potential of repowering onshore wind to achieve three key objectives is investigated: enhancing energy output, extending operational life, and contributing to net-zero targets. The analyses reveal significant increases in generation capacity through repowering, with benefits extending to local economies and emissions reduction. Additionally, technological advancements such as variable hub heights and wind turbine classes offer optimization opportunities for repowering projects. Challenges such as time-limited consents and financial disincentives prompt an examination of the complexities inherent in these issues and the opportunities they present. The study analyses the complicated interactions of engineering, environmental, and economic factors on a global scale. To overcome these challenges, the study recommends implementing stable financial support mechanisms, streamlining regulations through adaptive energy laws, and enhancing public engagement. Emphasising sustainable practices, the paper calls for clear legislative frameworks focused on wind turbine recyclability and collaborative efforts between the wind industry and communities to ensure environmentally responsible repowering projects.

Software and equations using segmental measures to estimate height in children and adolescents with cerebral palsy considering the level of gross motor function

In children with Cerebral palsy (CP) bone deformities create a difficulty in the collection of height measures by direct methods. Body segments are an alternative to study for anthropometric evaluation in children with CP. Motor compromise affects growth in these children. To our knowledge, no equations have been developed to estimate height that consider the level of involvement of children with CP. The aim was to develop equations to estimate height using segmental measures for children with cerebral palsy (CP). This was a cross-sectional study. The sample consisted of children and adolescents with CP of both sexes from 2 to 19 years old from five cities in Argentina. Children whose height and knee-heel height (KH) could be measured were included. Height, KH, and clinical covariables were collected. Linear regression models with height as the dependent variable and KH as predictors adjusted for significant covariates were developed and compared for R2, adjusted R2, and the root mean square of the error. 242 children and adolescents (mean age 9±4 years) with a confirmed diagnosis of CP were included. The interaction between height and other variables such KH, sex, GMFCS, and age was analyzed. Two equations were developed to estimate height according to GMFCS level (GMFCS Level I-III: H =1.5 × KH(cm)+2.28 × age(years)+ 51; GMFCS Level IV-V: H =2.13 × KH (cm)+ 0.91 × age(years)+37). The concordance correlation coefficient between estimated and observed height was 0.95 (95%CI [0.94; 0.96]). Height in children and adolescents with CP can be predicted using KH, GMFCS, and age. The equations and software can estimate height when this cannot be obtained directly.

Computational analysis of microchannel heat sinks with constant circular pin fins: Performance evaluation and optimization

This research entails a comprehensive computational simulation aimed at comparing the performance of microchannel heat sinks (MCHS) featuring 55-pin fins, characterized by constant circular pins with a diameter of 15µm, uniform spacing of 50µm, and variable heights ranging from 60 to 35µm. The primary objective was to assess the performance of these models with a reference Mini channel. Mesh independence validation was meticulously executed on MCHS with pin fins to ascertain the accuracy of the computational findings. The simulation encompassed seven Reynolds numbers within the range of 500–1500. The performance evaluation incorporated hydraulic and thermal factors, specifically pressure drop, Nusselt number, and the thermal performance factor (TPF). A holistic assessment of overall performance was achieved through the establishment of a heat sink thermal performance factor, accounting for both hydraulic and thermal aspects. The optimal geometry was determined based on this factor, and corresponding visual representations were generated to illustrate these findings.

The relationship beteen height, arm length, hand grip strength, togok flexibility to petanque shooting accuracy

Background and purpose This research aims to determine the relationship between height, arm length, hand grip strength, togok flexibility to petanque shooting accuracy. Material and methods This research was carried out at the Petanque Training Field of Tunas Pembangunan University and Petanque Field Karangasem. In this study used correlational method. Correlational research is a type of research with problem characteristics in the form of correlational relationships between two or more variables. The relationship between these variables can be determined through the calculation of the correlation coefficient using analysis techniques. In this study, a description will be made of the correlation and the amount of contribution between height to petanque shooting accuracy, arm length to petanque shooting accuracy, hand grip strength to petanque shooting accuracy and togok flexibility to petanque shooting accuracy. Data analysis in this study used multiple correlation analysis and partial correlation analysis. Results The results of this study show that the For the variables Body Height, Arm Length, Hand Grip Strength and Togok Flexibility on the Petanque Shooting Accuracy variable, the coefficient of determination or R Square was calculated at 0.785, meaning that the independent variables were (Body Height, Arm Length, Hand Grip Strength and Togok Flexibility). Simultaneously have a relationship with the dependent variable Petanque Shooting Accuracy of 0.785 (78.5%), while the remaining 21.5% (100% - 78.5% = 21.5%) is influenced by other variables outside the variables studied. Conclusions The conclusion of this research is variables of height, arm length, hand grip strength, togok flexibility together affect the dependent variable Petanque Shooting Accuracy by 78.5%.

APPLICATION OF MACHINE LEARNING MODELS AND GSA METHOD FOR DESIGNING STUD CONNECTORS

The design of stud connectors is aided by determining the relationship between shear strength and the input variables (number, diameter, height, tensile strength and elastic modulus of the studs, and compressive strength and elastic modulus of the concrete) that influence strength. Since strength is nonlinearly related to the influencing variables, which makes the predictions of the relevant empirical equations unreliable, the use of machine learning (ML) models is preferred. The prediction results of eight machine learning models were evaluated, including linear regression (LR1), ridge regression (RR), lasso regression (LR2), back-propagation artificial neural network (BP ANN), genetic algorithm optimized BP ANN (GA-BP ANN), extreme learning machines (ELM), random forests (RF), and support vector machines (SVM). The results show that the GA-BP ANN model is the most accurate model for prediction with a mean absolute percentage error (MAPE) of 6.17% and an R2 of 0.9599. Based on the GA-BP ANN model and the global sensitivity analysis (GSA) method, a new parameter importance analysis method was developed to compare the magnitude of the effect of different input variables on strength. It was found that stud diameter had the greatest effect on shear strength.

Linear systems characterization of the topographical spatial resolution of optical instruments

Lateral resolving power is a key performance attribute of Fizeau interferometers, confocal microscopes, interference microscopes, and other instruments measuring surface form and texture. Within a well-defined scope of applicability, limited by surface slope, texture, and continuity, a linear response model provides a starting point for characterizing spatial resolution under ideal conditions. Presently, the instrument transfer function (ITF) is a standardized way to quantify linear response to surface height variations as a function of spatial frequency. In this paper, we build on the ITF idea and introduce terms, mathematical definitions, and appropriate physical units for applying a linear systems model to surface topography measurement. These new terms include topographical equivalents of the point-, line-, and edge-spread functions, as well as a complex-valued transfer function that extends the ITF concept to systems with spatial-frequency-dependent topography distortions. As an example, we consider the experimental determination of lateral resolving power of a coherence scanning interference microscope using a step-height surface feature to measure the ITF directly. The experiment illustrates the proposed mathematical definitions and provides a direct comparison to theoretical calculations performed using a scalar diffraction model.

Constant static pressure strategy for residential kitchen exhaust system: Deducing control parameters from required exhaust rate and non-distributed data transmission

Roof fans have gradually replaced the non-powered hood as supplementary power to increase exhaust rate in high-rise residential kitchen shafts. However, an effective control strategy for roof fans is lacking. This paper studies the constant static pressure strategy and deduces its control parameters based on required exhaust rate and non-distributed data transmission. First, the static pressure set value (SV) is investigated under the worst exhaust condition, considering variations in shaft heights and measuring positions (MP). Then, an on/off mechanism is set up based on the measured static pressure and the fan frequency when the exhaust rate is adequate. Results show that under the recommended shaft sizes and design concurrent usage rates, the SVs for users' exhaust rate reaching 500 m³/h are −60, −60, and 0 Pa for 10/18/26-floor shafts when the MP is at a shaft's outlet, and roof fans are turned on when the static pressure reaches 100, 90, and 90 Pa and turned off when the fan frequency is below 32, 30, and 22 Hz. The MP at the shafts' outlet can keep the shaft at a slightly negative pressure. Control parameters for specific applications can be obtained through the proposed calculation process. An 18-floor shaft study found that the constant static pressure strategy can achieve 50 % energy savings compared to the constant frequency operation of the roof fan. These findings contribute to reliable control without users' distributed data transmission and to lower energy consumption of the residential kitchen exhaust system.

Modeling of nanoblood flow in an artery in presence of eco-friendly and biocompatible hybrid nanoparticles

Transferring biological fluid through arteries is a topic that has garnered serious interest in recent times, especially when it pertains to applications such as drug delivery. In our body, arteries serve as the primary conduits for blood flow and this study aims to model the blood flow in this situation. The working fluid is essentially pure blood, which acts as a base fluid, supplemented with nanoparticles of Titanium Dioxide (TiO2) and Gold (Au). Nanoparticles could change the thermal and rheological properties of blood which might be particularly advantageous for ensuring smoother flow or optimal distribution of drug molecules within the bloodstream. In the present work, a porous channel is considered with parallel walls that exhibit varying permeability on boundaries. Such a design enables the nanoblood to enter and exit the channel, mimicking certain natural processes like transvascular fluid exchange. Additionally, the variable height of the channel that expands and squeezes uniformly could be reminiscent of the pulsatile nature of blood flow seen in our arteries due to heartbeats. To understand the dynamics of this hybrid nanoblood flow, the governing equations are converted into a set of nonlinear ordinary differential equations using the similarity transformation approach. For solving these transformed equations, the research harnesses the BVP4C built-in function in MATLAB software. Through this computational approach, the research provides insights into the velocity and temperature profile of the fluid, the distribution of normal pressure, wall shear stress, and the Nusselt number concerning various parameters. The findings of the present study can be significant and useful in biological sciences and technologies and the detailed results are presented completely in the article’s body.