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On January 14th, 2022, a strong earthquake with a magnitude of M6.6 occurred in the south of Java Island, Indonesia, at a depth of 40 km. The earthquake was of an intensity up to MMI V (moderate shaking) in the area near the epicenter of the earthquake. The earthquake was also felt in Jakarta (MMI II), which is about 226 km away from the epicenter. A building in Jakarta was instrumented with accelerometers and recorded the floor vibration accelerations during the event. The record shows that the peak acceleration at the 12th floor was 3.614 times higher than the peak acceleration at the ground floor. The acceleration records were then analyzed to obtain the natural frequencies of the building, the displacement at the ground and 12th floors, and the vibration characteristics of the building due to the earthquake shaking. In order to study the performance of the building for future larger earthquake, a computer model of the building was also built. Comparison of the computer model of the building with the characteristics calculated using the recorded data was carried out for adjusting the behavior of the building. Parameters used for adjustment are building’s natural periods and damping ratios. After attempts to adjust those parameters, the model building is then used for calculating the threshold when the building enters inelastic phase and the percentage of inter-story drift. This can be used as a structural warning sign should larger earthquakes strike in the future.

Natural gas has diverse content such as Methane, Ethane, Carbon dioxide, Hydrogen Sulfide, and other gases. In addition, natural gas is formed over a very long time, where it comes from fossil fuels. Natural gas that has been treated and produced products are called synthesis gas which can be used to make ammonia (NH3). To produce ammonia, steam compounds (H2O) are used which are reacted with natural gas to produce hydrogen (H2) and Nitrogen (N2) obtained from the air. Ammonia manufacturing can be done by several processes, namely desulfurization (natural gas purification), Steam Reforming, Shift Converter, CO2 removal, methanation, and refrigeration units. The data used in this simulation is data on the ammonia plant at PT. Petrokimia Gresik. What is seen from this simulation is the influence of the composition of natural gas with variations in composition, namely 75% – 99% methane. The largest yield was obtained in the composition of 75% methane with an ammonia product yield of 82.34 tons/hour, this is because the division of the composition is divided propositionally into other compounds such as ethane, and propane, i-butane, etc. which have more H2 content. Then there is the ratio of methane flow rate to steam using a variation of 1:3.5 - 1:7.5 where the largest ammonia product is obtained from a ratio of 1:7.5 with ammonia product yields of 84.79 tons/hour because more and more steam causes the formation of more hydrogen. Furthermore, there is a ratio of methane flow rate to air with a variation of 1:5.5 - 1:7.5 where the largest ammonia product is obtained from a ratio of 1:5.5 with an ammonia product yield of 84.87 tons/hour because the air content consists of N2 and O2, where if the O2 content is a lot it will react with Methane so that the H2 produced will be less if methane reacts also with O2 not only with H2O.

Lake Sentani is one of the national priority lakes that must be saved from eutrophication and the threat of water quality degradation due to pollution. This study aims to assess the water quality parameters of Lake Sentani at ten study sites. We use two assessments to determine the trophic state, referring to Indonesia's criteria for lake trophic levels and the Trophic State Index (TSI). Also uses the Water Quality Index (WQI) to determine the suitability level of Lake Sentani water for various utilisation purposes. The study results show that the concentration of several parameters has exceeded the class-A to class-D quality standards. Lake Sentani tends to be eutrophic to hypereutrophic due to the high concentration of nutrient elements. Likewise, the TSI method classifies Lake Sentani into eutrophic to hypertrophic states (TSITP: 68.21–79.19). Lake Sentani's water transparency level includes eutrophic and mesotrophic (TSISD: 44.47–47.94) states. Based on the WQI value, the water quality of Lake Sentani is predominantly classified as poor to marginal as a source of drinking water (WQI: 44.56–54.10), so it is not suitable for use as a source of drinking water. Water quality is marginal if used to support recreational activities (WQI: 55.56–63.92). For use in aquaculture and irrigation, the water quality of Lake Sentani is classified as fair (WQI: 65.64–76.91) and good to excellent (WQI: 89.01–100.00), respectively. So, it is suitable for supporting aquaculture activities and as a water source for irrigation.

Local muscle quality imaging in human calf by phase angle electrical impedance tomography (ΦEIT) has been proposed to monitor the local muscle aging (MA), local muscle fat infiltration (FI), and local muscle cross-sectional area (CSA) for the daily monitoring of muscle quality. The MA is assessed by the calf-specialized phase angle Jacobian matrix $^{\boldsymbol {\Phi }}$ J, the FI is estimated by the phase angle distribution $\Phi _{M}$ , and the high-intensity binarization of phase angle CSA predicts CSA ( $\widehat {\Phi _{M}}$ ). The ΦEIT is applied to 14 healthy subjects categorized into the young subject group (age $\le 30$ , $n = 7$ ) and middle-aged subject group (age > 30, $n = 7$ ). An independent samples t-test was conducted to elucidate the statistical significance of spatial-mean phase angle $\langle \Phi \rangle $ for MA assessment, spatial-mean phase angle $\langle \Phi \rangle _{M}$ for FI estimation as compared with FI by conventional ultrasound (uFI), and phase angle CSA ( $\widehat {\Phi _{M}}$ ) for CSA prediction compared to muscle area by the conventional ultrasound CSA (uCSA). The results from the independent t-test show that the ΦEIT correlates well with the subject’s age, uFI, and uCSA. The $\langle \Phi \rangle $ is significantly correlated to the MA ( $n \, =14$ , $p \lt 0.001$ ) in the young and middle-aged groups. The $\langle \Phi \rangle _{\mathbf {M}}$ is related substantially to FI ( $n =14$ , $p \lt 0.05$ ) in the young and middle-aged groups. the $\widehat {\Phi _{M}}$ is significantly related to CSA ( $n =14$ , $p \lt 0.05$ ) in the young and middle-aged subject groups.

The propagation of waves in a homogeneous, isotropic linear elastic half-space is investigated herein. A buried point pulse generates a vibration in an arbitrary direction. Both source and receiver points are located in the interior of the three-dimensional domain. To solve the elastodynamic problem, also known as Lamb's problem, the source image and the superposition principle are both used to derive a numerical transient solution. Accordingly, the transient response of the problem in the time domain can be considered as the superposition of the responses to the real and imaginary sources in the full-space and some additional vertical loads on the surface of the half-space. The additional vertical loads are distributed over a rectangular area on the surface of the half-space and are space- and time-dependent functions that vary with time as the Heaviside step, the Dirac delta, and derivatives of the Dirac delta functions. The motion at depth due to a point source applied on the surface is obtained using some well-known approaches reported in the literature. To achieve the Laplace transform displacement, Helmholtz potentials have been employed for the displacement field and the Laplace transform wave equation as well as the Hankel transform of boundary conditions have been satisfied. The inverse Laplace transform (time-domain solutions) is found via a modified version of some other methods reported in the literature. The solutions obtained in this way automatically satisfy the traction-free boundary conditions over the surface of the half-space and can be implemented in the three-dimensional time-domain boundary element method (BEM), and no discretization of the ground surface is needed.

• A half-space TD-BEM model was proposed for analyzing the corrugated orthotropic stratum. • A stepped incremental meshing was applied for preparing the model of widespread boundaries. • Some new results were illustrated to obtain the surface response of the orthotropic layer. In this paper, the model of a linear corrugated orthotropic stratum above a semi-infinite substratum is elaborated by a half-space time-domain boundary element method (TD-BEM) subjected to oblique incident plane SH waves. The ground surface and the interface are corrugated in a similar ratio using a Gaussian-shaped function. In the used approach, only the corrugated boundaries are required to be discretized. An incremental mesh scheme is applied to reduce the number of boundary elements in the large width of the interface. After developing the algorithm and solving a verification example, the seismic ground response is obtained and compared by assuming three cases of the model based on the isotropy factor, one isotropic case, and two orthotropic cases. Some effective parameters, including the shape ratio of the corrugation, frequency content, and wavefront propagation angle, are also considered to obtain the amplification pattern of the surface. Finally, by developing the method to multi-layered medium, its efficiency is investigated in the analysis of orthotropic heterogeneous models with more degrees of freedom. The results showed that both geometry and material factors were directly affected by the phenomenon of wave propagation so that the corrugation depth and the velocity of the wavefront in different directions could significantly control the response of the ground surface. [ABSTRACT FROM AUTHOR]

Delay of medical treatment among Indonesian women was a common phenomenon. Culturally, Indonesians women rely on their family for decision-making that might suspend medical treatment and poorer diagnoses. Understanding decision-making experience is a crucial element required to shorten cancer treatment delays.

Volatile organic compounds (VOCs) range in their reaction rates with atmospheric oxidants by several orders of magnitude. Therefore, studying their atmospheric concentrations across seasons and years requires isomer resolution to fully understand their impact on oxidant budgets and secondary organic aerosol formation. An automated gas chromatograph/flame ionization detector (GC-FID) was developed for hourly sampling and analysis of C5–C15hydrocarbons at remote locations. Samples are collected on an air-cooled multibed adsorbent trap for preconcentration of hydrocarbons in the target volatility range, specifically designed to minimize dead volume and enable rapid heating and sample flushing. Instrument control uses custom electronics designed to allow flexible autonomous operation at moderate cost, with automated data transfer and processing. The instrument has been deployed for over two years with samples collected mid-canopy from the Virginia Forest Laboratory located in the Pace research forest in central Virginia. We present here the design of the instrument itself, control electronics, and calibration and data analysis approaches to facilitate the development of similar systems by the atmospheric chemistry community. Detection limits of all species are in the range of a few to tens of ppt and the instrument is suitable for detection of a wide range of biogenic, lightly oxygenated, and anthropogenic (predominantly hydrocarbon) compounds. Data from calibrations are examined to provide understanding of instrument stability and quantify uncertainty. In this work, we present challenges and recommendations for future deployments, as well as suggested adaptions to decrease required maintenance and increase instrument up-time. The presented design is particularly suitable for long-term and remote deployment campaigns where access, maintenance, and transport of materials are difficult.

Multinode electrical impedance tomography (mnEIT) throughout whole-body electrical muscle stimulation (wbEMS) has been proposed for the simultaneous imaging of muscle compartments response. mnEIT has two characteristics, which are: 1) network hardware for synchronized measurement in multinode simultaneously and 2) nodal fast Fourier transform (FFT) for canceling time-varying noise. By mnEIT, the muscle compartments response in the upper arm and thigh of eight healthy subjects is imaged throughout wbEMS under four voltage intensity levels. According to the reconstructed images of conductivity distribution $\sigma $ in prior training and throughout wbEMS, the conductivity distribution trend of the upper arm and thigh is boosted along with the rise of wbEMS voltage intensity. As the hardware error evaluation, the normalized spatial-mean impedance error $\varepsilon _{f}$ of mnEIT is relatively higher in the increase of frequency, while the average error $\langle \varepsilon \rangle $ is 7.521%, respectively. Here, our mnEIT has the best result at $\varepsilon _{f} < \langle \varepsilon \rangle $ , which occurred at $f \le2500$ Hz that covers the frequency selection $f_{1} =500$ Hz and $f_{2} =1000$ Hz to obtain the best visualization of conductivity distribution $\sigma $ . Meanwhile, based on the Pearson correlation as the statistical evaluation, the mnEIT has a relatively high accuracy value at the upper arm $r_{\mathrm {arm}}$ = 0.9391 and thigh $r_{\mathrm {thigh}} =0.894$ .

• Scattering attenuation of transient SH -wave. • Orthotropic Gaussian-shaped sedimentary basin. • Time-domain boundary element method. • Illustrating the responses in time and frequency domains. • Isotropy-factor, wave angle, and geometrical effect of sedimentary basin. The surface motion of an orthotropic Gaussian-shaped sedimentary basin embedded in a linear elastic half-space was successfully obtained under transient SH -wave propagation. In the use of the time-domain boundary element approach, a simple model was developed only by discretizing the interface. To achieve better convergence of the response, an attenuation rule was implemented with the assistance of the reduction exponential function applied in the boundary integral equations. After a brief overview of the method, the heterogonous sub-structured basin model was created and decomposed into two parts to satisfy the modified continuity conditions based on the normal direction at the interface node position. Then, the coupled matrices were temporarily solved at each time-step to obtain the boundary values. The developed computer code was tested by solving a validation example. Finally, to illustrate the valley surface response in the time/frequency-domain, a general sensitivity analysis was performed by considering the parameters of frequency, shape-ratio, isotropy-factor, and wave angle in the form of snapshots, seismograms, and amplification patterns. The results showed that the effect of orthotropic anisotropy was very efficient on the ground response and different seismic patterns on the surface of sedimentary basins were extracted by changes in the quantity of this parameter. [ABSTRACT FROM AUTHOR]

In this paper, the seismic response of elastic homogeneous ground surface was presented in the presence of unlined horseshoe-shaped underground cavities subjected to obliquely propagating incident SH-waves by using the time-domain half-plane boundary element method (BEM). The Ricker wavelet was considered for the incident wave function. In the use of the proposed method, the boundary around the tunnel was only required to be discretized. After comparing the results of the present study with existing analytical responses, it was found that the method had good accuracy in modeling horseshoe-shaped tunnels. The responses are presented as two-/three-dimensional diagrams in the time/frequency domain. Also, a comparative study is carried out between circular and horseshoe cross-sections to observe the effect of the geometry on the response pattern. The results show that the existence of subsurface openings as well as horseshoe-shaped cavities has a significant effect on the variation of seismic patterns and critical states of the ground surface. The used method can be proposed to geotechnical engineers for preparing simple underground models to achieve the transient responses.

In this paper, a half-plane time-domain boundary element method is applied to obtain the seismic ground response, including a subsurface box-shaped lined tunnel deployed in a linear homogenous elastic medium exposed to obliquely incident SH-waves. Only the boundary around the tunnel is required to be discretized. To prepare an appropriate model by quadratic elements, a double-node procedure is used to receive dual boundary fields at corners as well as change the direction of the normal vector. After encoding the method in a previously confirmed computer program, a numerical study is carried out to sensitize some effective parameters, including frequency content and incident wave angle for obtaining a surface response. The depth and impedance ratio of the lining are assumed to be unvaried. The responses are illustrated in the time and frequency domains as two/three-dimensional graphs. The results showed that subsurface openings with sharp corners distorted the propagation path of the anti-plane waves to achieve the critical states on the ground surface. The present approach can be proposed to civil engineers for preparing simple underground box-shaped models with angular boundaries.

ABSTRACTHow countries, particularly low- and middle-income economies, should pay the coronavirus disease 2019 (COVID-19) vaccine is an important and understudied issue. We undertook an online survey to measure the willingness-to-pay (WTP) for a COVID-19 vaccine and its determinants in Indonesia. The WTP was assessed using a simple dichotomous contingent valuation approach and a linear regression model was used to assess its associated determinants. There were 1,359 respondents who completed the survey. In total, 78.3% (1,065) were willing to pay for the COVID-19 vaccine with a mean and median WTP of US$ 57.20 (95%CI: US$ 54.56, US$ 59.85) and US$ 30.94 (95%CI: US$ 30.94, US$ 30.94), respectively. Being a health-care worker, having a high income, and having high perceived risk were associated with higher WTP. These findings suggest that the WTP for a COVID-19 vaccine is relatively high in Indonesia. This WTP information can be used to construct a payment model for a COVID-19 vaccine in the country. Nevertheless, to attain higher vaccine coverage, it may be necessary to partially subsidize the vaccine for those who are less wealthy and to design health promotion materials to increase the perceived risk for COVID-19 in the country.

The growth plate is cartilage tissue found at the end of long bones in children, responsible for longitudinal bone growth. Injuries to the growth plate cartilage often lead to unwanted bony repair, resulting in growth disturbances such as limb length discrepancy and angulation deformity in children. There is currently no clinical treatment that can fully repair an injured growth plate. Tissue engineering is promising for regeneration of growth plate. Adipose-derived stromal vascular fraction highlight the promising potential as tissue engineering therapy for inducing regeneration of injured growth plate and able to reduce the formation of bony repair that can lead to deformity and limb length discrepancy. Using an animal model of growth plate injury, bone bridge formation is evaluated after 28 days using Enzyme-linked Immunoassay, radiology, histopathology and Immunofloresence examination. Radiological analyses performed by evaluation of grey value using ImageJ software and diameter bone bridge measured from the end to end distance between uninjured growth plate evaluated by histopatology examination. Enzyme-linked Immunoassay and immunofloresence are used to evaluate chondrocyte and chondrogenic marker within the defect. The result shows in group with Adipose-derived stromal vascular fraction have a significant lower bone bridge formation compare to positive control group. This current study represents the first work that has utilized this animal model to investigate whether Adipose-derived stromal vascular fraction can be used to initiate regeneration at the injured growth plate.

One of the most important part of tissue engineering (TE) is a matrix called scaffold. A good scaffold integrates with the host tissue and support the growth and differentiation of the cells. Collagen is the most abundant protein in the ECM and has been considered to be a group of proteins with a characteristic molecular structure—fibrillar structure, which contributes to the extracellular scaffolding.

Innovative seismic analysis: DASBEM introduces a novel numerical model for studying seismic effects on complex terrains.Orthotropy’s impact: Beyond impedance ratio, the study underscores the crucial role of orthotropy in shaping ground movement.Practical applications: The research provides insights applicable to real-world scenarios, enhancing seismic risk assessments for various topographies.

Indonesia with abundant limestone raw materials, lightweight brick is the most important component in building construction, so it needs a light brick product that qualifies in thermal, mechanical and acoustic properties. In this paper raised the lightweight brick domains that qualify on the properties of thermal conductivity as building wall components.The advantage of low light density brick (500-650 kg/m3), more economical, suitable for high rise building can reduce the weight of 30-40% in compared to conventional brick (clay brick). To obtain AAC type lightweight brick product that qualifies for low thermal and density properties to the effect of Aluminum (Al) additive element variation using artificial neural network (ANN). The composition of the main elements of lightweight brick O (29-45 % wt), Si (25-35% wt) and Ca (20-40 % wt). Mixing ratio of the main element of light brick (Ca, O and Si) with Aluminum additive element (Al), is done by simulation method of artificial neural network (ANN), Al additive element as a porosity regulator is formed. The simulation of thermal conductivity to the influence of main element variation: Ca (22-32 % wt), Si (12-33 % wt). Simulation of thermal conductivity to effect of additive Al variation (1-7 % wt). Simulation of thermal conductivity to density variation (500-1200 kg/m3). The simulated results of four AAC brick samples showed the thermal conductivity (0.145-0.192 W/m.K) to the influence of qualified Aluminum additives (2.10-6.75 % wt). Additive Al the higher the lower density value (higher porosity) additive Al smaller than 2.10 % wt does not meet the requirements in the simulation.Thermal conductivity of AAC light brick sample (0.184 W/m.K) the influence of the main elements that qualify Ca (20.32-30.35 % wt) and Si (26.57 % wt). Simulation of artificial neural network (ANN) of light brick shows that maximum allowable Si content of 26.57 % wt, Ca content is in the range 20.32-30.35 % wt, and the minimum content of aluminum in brick is light at 2.10 % wt. ANN tests performed to predict the thermal conductivity of light brick samples obtained results of the average AAC light brick thermal conductivity of 0.151 W/m.K. The best performance with Artificial Neural Network (ANN) characteristics has a validation MSE of 0.002252.

This study presents the formulation of a finite-element numerical method for the analysis of shear wave dispersion out of plane SH. Also, it evaluates the seismic behavior of alluvial valleys located in a semi-infinite rigid space. This formulation is implemented in computer codes in time domain. To examine the accuracy of the program, various examples are solved and some numerical considerations in the dynamic analysis of the topographic feature are investigated by parametric studies. The results indicate that the appropriate time step in the finite-element method (FEM) is 45/1000 of the predominant period of the incident wave. The appropriate length of the element should be selected for placing at least eight nodes on the smallest wavelength. Increasing Gaussian points in integrating mass matrices in comparison with stiffness matrices is not effective in the accuracy of results. It was found that the choice of δ> 0.5 in Newmark’s integration method reduced the amplitude, but the change in the $$\alpha$$αvalue did not affect the results. The effect of a feature on the ground response is only noticeable if the wavelengths are comparable with the dimensions of the feature.

Heat treatment of T-Joint’s steel arc welded are performed are investigated in this research. The heat treatment process that used were annealing and quenching. The microstructure was investigated by optical microscope. The mechanical behavior of the samples was investigated using universal tensile testing machine for tensile test and Microvickers hardness method for hardness testing. The microstructure of welding zone of welding metals with various heat treatments is grain boundary ferrite, Widmanstatten ferrite and acicular ferrite. The weld metal with quenching treatment has a highest tensile strength with tensile strength 197.97 Mpa. The quenching process increases the tensile strength by 49.58 %. The distortion value in weld metal without heat treatment, quenching and annealing is 0.11mm; 0.04 mm and 0.08 mm respectively. The hardness number of weld metals with quenching process have a highest number base metal, HAZ and weld metals. Results showed that the mechanical properties of T-joints steel arc welded can be improved by various heat treatments.

Scientific research plays a key role in the advancement of human knowledge and pursuit of solutions to important societal challenges. Typically, research occurs within specific institutions where data are generated and subsequently analyzed. Although collaborative science bringing together multiple institutions is now common, in such collaborations the analytical processing of the data is often performed by individual researchers within the team, with only limited internal oversight and critical analysis of the workflow prior to publication. Here, we show how hackathons can be a means of enhancing collaborative science by enabling peer review before results of analyses are published by cross-validating the design of studies or underlying data sets and by driving reproducibility of scientific analyses. Traditionally, in data analysis processes, data generators and bioinformaticians are divided and do not collaborate on analyzing the data. Hackathons are a good strategy to build bridges over the traditional divide and are potentially a great agile extension to the more structured collaborations between multiple investigators and institutions.

A direct half-plane time-domain boundary element method (BEM) was developed and successfully applied to analyze the transient response of ground surface in the presence of arbitrarily shaped lined tunnels, embedded in a linear elastic half-space, subjected to propagating obliquely incident plane SH-waves. To prepare the model, only the interface and inner boundary of the lining need to be discretized. The problem was decomposed into a pitted half-plane and a closed ring-shaped domain, corresponding to the substructure procedure. After computing the matrices and satisfying the compatibility as well as boundary conditions, the coupled equations were solved to obtain the boundary values. To validate the responses, a practical example was analyzed and compared with those of the published works. The results showed that the model was very simple and the accuracy was favorable. Advanced numerical results were also illustrated for single/twin circular lined tunnels as synthetic seismograms and three-dimensional frequency-domain responses. The method used in this paper is recommended to obtain the transient response of underground structures in combination with other numerical methods. [ABSTRACT FROM AUTHOR]

The aimed of this research is to investigate the effect of T-Joint’s root gap on physical and mechanical properties of weld metal. Low carbon steel were joined in T-joint types using MIG (Metal Inert Gas) with variation of root gap. The root gap used were 0 mm, 3 mm and 6 mm. The physical properties examined with chemical composition, microstructure and corrosion using optical microscope. The mechanical properties were measured with respect to the strength and hardness using Universal testing machine and Vickers Microhardness. The results show that the highest value found in welds with a gap of 3 mm with a value of 163.57 MPa. Hardness value is directly proportional to the tensile strength of the material. The highest value found in welds with root gap of 3 mm, followed by root gap of 6 mm, and 0 mm Hardness values in the welding area is higher than the parent metal and HAZ because the number of Si, Mn and Cu elements in the welding metals are bigger than base metal. Weld with all variation of root gap have a good corrosion resistance because the corrosion rate in welds with various root gap have a value below 0.02 mmpy. Microstructure of weld metals were Accicular ferrite, Widmanstatten ferrite, and grain boundary ferrite, while microstructure of base metal and HAZ were ferrite and perlite.

Gibberellic Acid-Stimulated Arabidopsis (GASA) proteins are present in various plants and have a role in plant growth, stress responses, and hormone crosstalk. GASA coding sequences in barley were discovered in this study. We then investigated gene and protein structure, physicochemical characteristics, evolutionary and phylogenetic relationships, promoter region, post-translational modification, and in silico gene expression. Finally, real-time quantitative PCR (RT-qPCR) was used to examine the expression of GASA genes in root and shoot tissues under drought stress. We found 11 GASA genes spread across six of seven chromosomes in the barley genome. A conserved GASA domain and 12-cysteine residues at the C-terminus were included in the proteins. All GASA genes contained secretory signal peptides. The GASA genes in Hordeum vulgare(HvGASA) have been classified into three subfamilies based on evolutionary analysis. According to synteny analyses, segmental duplications are significant in forming the GASA gene family. According to the cis-elements analyses, GASA genes may be induced by a variety of phytohormones and stresses. Tissue-specific expression analysis indicated that GASA genes had varied expression patterns in different tissues. Contrary to common perception, the expression study of GASA genes under biotic and abiotic stresses revealed that GASA genes are more induced by abiotic stresses than biotic stresses. The qPCR confirmed the response of GASA genes to abiotic stresses and showed different expression patterns of these genes under drought stress. Overall, these results can improve our knowledge about the function of GASA genes and provide data for future researches.

In this paper, stress behavior of shallow tunnels under simultaneous non-uniform surface traction and symmetric gravity loading was studied using a direct boundary element method (BEM). The existing full-plane elastostatic fundamental solutions to displacement and stress fields were used and implemented in a developed algorithm. The cross-section of the tunnel was considered in circular, square, and horseshoe shapes and the lateral coefficient of the domain was assumed as unit quantity. Double-node procedure of the BEM was applied at the corners to improve the model including sudden traction changes. The results showed that the method used was a powerful tool for modeling underground openings under various external as well as internal loads. Eccentric loads significantly influenced the stress pattern of the surrounding tunnel. The achievements can be practically used in completing and modifying regulations for stability investigation of shallow tunnels.

Shot-peening is one of the surface modification methods to increase material hardness and smoothen its surface at the same time. SS-316L, one type of biocompatible material, is commonly used in medical field particularly for joining fractured bones. However, the surface-crack-prone characteristic of SS-316L has limited its application to be used for such application. In this research, steel balls with diameter 0.4 mm is subjected to the surface of SS-316L Osteosynthesis Plate with variation of time; 9, 10, 11 and 12 minutes holding at constant pressure of 6 bar. The nozzle-to-plate distance is fixed at 100 mm. The impact of the shot balls is a deformed surface and produces a flat-like structure on osteosynthesis plate shot in 12 minutes time. The result shows that shot peening of SS 316L gives its best microstructure after 12 minutes of treatment.

Exoskeleton is an external cantilever to support inner living organism organs. Some animals have the exoskeleton attached naturally on their body as those found in a million species of arthropods order. The word “Arthropods” itself are related to their body plan—their segmented body, hard exoskeleton, and jointed appendages [1]. This structure inspired us to implement the exoskeleton to help humans who are permanently or temporarily have problems with their lower limb, for example those who are recovering from stroke or road-accidents. Stroke is a condition where lower limb is partially paralyzed (Hemiplegia) and causes inability to walk normally or to do other physical activities [2].The exoskeleton consists of four main parts; frame for the leg (XOTF), frame for the thigh (XOF), the belt, and the controller stick. The frame is designed using lightweight material. Considering the material’s availability and price at the local market, we choose Aluminum Composite Panel (ACP) as frame’s material. The belt acts as the brain for the exoskeleton, where it provides electrical power and the source of motion. There are four frames on the exoskeleton which moves simultaneously while walking. In the design, we use two joy-sticks as main controller to adjust position of each exoskeleton frame. The sticks are attached to standing-canes which help the user to improve stability. The sticks have buttons and lever to control the exoskeleton and adjust thighs and legs fit for several moves; stand, sit, walk, going up and downstairs, or any other position which need balance and power.The exoskeleton design has been tested for its motion and stability. The results show that the design is suitable for those who are fully or partially paralyzed on their lower limb.

Dynamic Compression Plate (DCP) is a plate made of biomaterials like stainless steel 316L (SS-316L) or titanium, which is used for joining fractured/broken bones for fast recovery. Due to its excellent properties on corrosion, toughness, and hardness; SS-316L is widely used for medical application. Despite its excellent properties, the surface of SS-316L commonly degraded after machining. Therefore, the surface of SS-316L needs to be treated before further use. Shot peening is one of the methods to increase the surface hardness and roughness of material. This research aims to investigate the effect of shot peening to the surface of DCP made of SS-316L from its microstructures, surface roughness, and hardness. In this research, the DCP is designed for joining arms, which are upper-arm (humerus) and forearm (radius and ulna). First we machined the DCP to have holes and bend the plate to match the user bone structure. The DCP is 105 mm × 12 mm × 4 mm in dimension and has 6 holes, 5 mm diameter each, with holes aligned to the plate. After machining, the surface is modified by shot peening using following properties: steel ball (0.4 mm in diameter and hardness 250 HV), 100 mm nozzle-to-plate distance, and shot for 10 minutes. Our parameters are variations in pressure, ranging from 4 to 6 bar. The microstructure of the treated surface was analyzed after shot peening. The result shows that the shot peening treatment of SS-316L has increases its surface hardness and roughness with significant change on its microstructure, which makes a better surface characteristics for DCP.