Normal Angle Research Articles

The Effect Of Neck Pain On Craniovertebral Angle Due To The Use Of Smartphone As A Learning Media For Physiotherapy Students In Widya Husada University Semarang

The COVID-19 pandemic in Indonesia affects student learning methods, one of which is the change from offline to online. Learning activities using a smartphone for a long time causes the neck position to become not ergonomic. The result will be neck pain. The purpose of this study was to determine the effect of the craniovertebral angle on neck pain in physiotherapy students at Widya Husada University Semarang. The research method using observational cross sectional. The results showed that most of the samples had normal cranivertebral angle (CVA) with mild neck pain and neck pain frequency more than 1 time per week. While the strong correlation is CVA is directly proportional to the frequency of neck pain.

Translated article] Syndesmosis injury associated with high-energy tibial shaft fractures: Case series of a misdiagnosis rupture

IntroductionAnkle syndesmosis injuries can be associated with a spiral mechanism on tibial shaft fractures. We are not aware if there is evidence of the incidence of ipsilateral syndesmotic lesson associated to high-energy tibial shaft fracture mechanisms. The aim of this study was to analyze the incidence of syndesmotic injuries associated with high-energy tibial shaft fractures. MethodsTwo hundred thirty-three diaphyseal tibial fractures operated between January 2007 and January 2017, the fracture patterns were analyzed, they were classified according to AO, the talocrural angle was measured, they analyzed failures and reoperations and described a novel failure method. ResultsFrom a total of 234 fractures that met the inclusion criteria, 159 (64.96%) suffered closed fractures and 75 (32.05%) where open fractures. According to the AO classification system: 152 (64.10%) were simple patterns 42.A; 49 (20.94%) wedge type patterns 42.B and 33 (14.10%) complex patterns 42.C. Ten patients, a 4.27% of the sample, shown an increased talocrural angle in the postoperative radiographs, evidencing shortening of the fibula. Nine patients underwent surgery, the remaining patient was lost to follow-up. All the treated patients presented restoration of the normal talocrural angle. ConclusionThe incidence of syndesmotic injuries associated with high-energy tibial shaft fractures reaches 4.27%. We think that is necessary to evaluate the ankle and syndesmosis in all tibial shaft fractures, even with high-energy patterns, not only in spiral patterns.

Analysis of transmission spectra in one-dimensional ternary photonic crystals with complex unit cell

We investigate the light transmission spectra of a one-dimensional semiconductor ternary photonic crystal with a complex unit cell composed of different combinations of two three-layers (symmetric and asymmetric) using the transfer matrix method. The transmittance properties of such photonic crystals are analyzed numerically for the normal and oblique incidence angles of electromagnetic radiation. The complete transmission spectra for the complex ternary photonic structures have been verified from the Brewster angle. Special attention is paid to the study of light transmission spectra dependencies as a function of the thicknesses of layers in the complex unit cell. The proposed structure can be used to design the optical wide-band filters, omnidirectional reflectors at the infrared and terahertz regimes.

Gap Formation Around 0.5Ωe in the Whistler‐Mode Waves Due To the Plateau‐Like Shape in the Parallel Electron Distribution: 2D PIC Simulations

AbstractThe power gap around 0.5Ωe (where Ωe is the equatorial electron gyrofrequency) of whistler‐mode waves is commonly observed in the Earth's inner magnetosphere, but its generation mechanism is still under debate. By performing two‐dimensional particle‐in‐cell simulations in a uniform background magnetic field, we investigate the spectral properties of whistler‐mode waves excited by temperature anisotropic electrons. The waves have positive growth rates in a wide range of normal angles (θ ≈ 0°–35°), resulting in the generation of both parallel and nonparallel waves. Although the nonparallel wave modes are weaker than the parallel ones, they can cause the plateau‐like shape around 0.5 VAe (where VAe represent the electron Alfven speed) in the parallel direction of electron velocity distribution. The plateau‐like electron component can then lead to severe damping in the waves around 0.5Ωe via the cyclotron resonance, and the power gap is formed. This mechanism is called as “spectrum bite”. Our study sheds fresh light on the well‐known gap formation at ∼0.5Ωe in the whistler‐mode waves, which is ubiquitously detected near the equator in the inner magnetosphere.

Orthodontic Treatment of Severe Bimaxillary Dentoalveolar Protrusion with Skeletal Class II Malocclusion Without Using Miniscrews

Bimaxillary dentoalveolar protrusion is characterized by the proclined anterior teeth, protrusive lips, and a convex profile. A proper orthodontic treatment modality for efficient anchorage control is necessary to retract the anterior teeth and improve the facial esthetics significantly. The commonly used miniscrew could provide absolute anchorage, however, it is accompanied by some risks and complications, especially in adolescent females. This case report described a 16-year-old female with diagnosis of skeletal Class II, normal mandibular plane angle, and Angle Class I malocclusion associated with proclined upper and lower anterior teeth, excessive overjet, and a convex profile with lip incompetence. We extracted her four first premolars first. Then, the Tip-Edge Plus bracket system and differential force method were applied to replace the temporary anchorage device. The total treatment duration was 27 months. Her dentoalveolar protrusion was decreased, both lips were significantly retracted, the mentalis strain was reduced, and her chin projection was improved. This case demonstrated that differential tooth movement with controlled light orthodontic forces could be an effective strategy to treat severe bimaxillary protrusion.

Effect of Gear Design Parameters on Stress Histories Induced by Different Tooth Bending Fatigue Tests: A Numerical-Statistical Investigation

The characterization of new materials for enabling gear design is definitely a fundamental objective in the gear industry and research. Single Tooth Bending Fatigue (STBF) tests can be performed to speed up this process. However, it is well known that STBF tests tend to overestimate material strength compared to tests performed directly on meshing gears (MG) which, in turn, require an excessively long test time. Therefore, it is common practice to use a constant correction factor fkorr of 0.9 to translate STBF results for designing actual MG (e.g., via ISO 6336). Recent works involving a combination of Finite Element Models (FEM) and multiaxial (non-proportional) fatigue criteria based on the critical plane concept have highlighted that the assumption of considering fkorr as a constant independent of the gear design parameters leads to inaccurate results. However, in previous studies, no correlation between fkorr and gear design parameters has emerged. In the present paper, the influence of the normal pressure angle (αn), the profile shift coefficient (x*), and the normal module (mn) on fkorr was investigated by analyzing FEM simulations with the Findley fatigue criterion. 27 gear geometries were studied by varying the above 3 parameters in 3 levels (full factorial DOE). These geometries were simulated in both MG and STBF configurations. The results of the 54 FEM simulations were analyzed by applying the Findley fatigue criterion and the corresponding fkorr were calculated. The correlation between fkorr and αn, x* and mn was investigated using the Analysis of Variance (ANOVA) technique. The results show that the only gear design parameter influencing fkorr is x* hence, a regression model for fkorr including x* has been developed. This latter has been then adopted for calculating and comparing fkorr values from other combination of the parameters found in literature, giving good correspondence.

Deformation and film formation mechanisms during high velocity impact of silicon carbide nanoparticles

Molecular dynamics simulations were conducted to study the factors that affect deformation behavior that occurs during high-speed impact of SiC nanoparticles onto flat substrates. For these simulations, a 6 nm particle was impacted onto a (110)-oriented SiC substrate and the particle impact velocity (3000–4000 m/s), particle orientation, and impact angle (0°–75°) were systematically varied. A broad range of impact behaviors were observed and categorized from elastic with no particle sticking to plastic with significant particle deformation and sticking. High impact velocities and near normal impact angles were found to enhance particle sticking. Particle orientation also had an effect. For some impact conditions, disordering of the lattice within the particle was observed and quantified. Particle impacts that resulted in the greatest degree of amorphization also exhibited significant deformation. This suggests that amorphization followed by viscous flow in the disordered region of the particle is the primary deformation mechanism responsible for particle sticking.

Active VLF Transmission Experiments Between the DSX and VPM Spacecraft

AbstractThis study presents results from magnetic field line conjunctions between the medium‐Earth orbiting Demonstration and Science Experiments (DSX) satellite and the low‐Earth orbiting (LEO) very low frequencies (VLF) Propagation Mapper (VPM) satellite. DSX transmitted at VLF toward VPM, which was equipped with a single‐axis dipole electric field antenna, when the two spacecraft passed near the same magnetic field line. VPM did not observe DSX signals in any of the 27 attempted conjunction experiments; the goal of this study, therefore, is to explain why DSX signals were not received. Explanations include (a) the predicted power at LEO from DSX transmissions was too low for VPM to observe; (b) VPM's trajectory missed the “spot” of highest intensity due to the focused ray paths reaching LEO; or (c) rays mirrored before reaching VPM. Different combinations of these explanations are found. We present ray‐tracing analysis for each conjunction event to predict the distribution of power and wave normal angles in the vicinity of VPM at LEO altitudes. We find that, for low‐frequency (below 4 kHz) transmissions, nearly all rays mirror before reaching LEO, resulting in low amplitudes at LEO. For mid‐ and high‐frequency transmissions (∼8 and 28 kHz respectively), the power at LEO is above the noise threshold of the VPM receiver (between 0.5 μV/m and 1 μV/m). We conclude that the antenna efficiency and plasmasphere model are critical in determining the predicted power at LEO, and are also the two most significant sources of uncertainty that could explain the apparent discrepancy between predicted amplitudes and VPM observations.

Side-to-Side Difference of Metatarsal Rotation in Normal Individuals.

A previous study defined the normal first metatarsal pronation angle (MPA) as <16 degrees and normal α angle as <18 degrees. The primary purpose of this study was to assess the side-to-side variation in first metatarsal pronation between feet in normal individuals. MPA and α angles were measured on standardized coronal weightbearing computed tomography slices. Pairedt tests were used to test significance of mean side-to-side differences in a population of 63 normal, asymptomatic individuals. The mean side-to-side difference in first metatarsal pronation was 4.3 degrees (95% CI 3.3, 5.2 degrees) for MPA and 4.9 degrees (95% CI 3.8, 6.0 degrees) for α angle. The normative range for side-to-side difference was calculated as 12 degrees for MPA and 14 degrees for α angle, as defined by 2 SDs from the mean. In a cohort of normal patients, the mean difference in first metatarsal pronation between sides was approximately 4 to 5 degrees based on MPA and α angle. However, considerable variation in differences was observed. These findings may be considered when assessing first metatarsal pronation using population-based values as it may influence thresholds for identifying pathology in an individual.

Broadband pyramid antireflective structure on chalcogenide glasses by the hot embossing method for infrared photonics

Pyramidal antireflective structures were produced by hot embossing single- and double-sides of an amorphous GeSe4 optical element. The optical performances were measured across the wavelength range from 2 µm to 15 µm. The transmittance at normal incident angle was increased up to 75.6% and 79.8% for single and double-side embossing respectively. The experimental results were in close agreement with simulation performed using the rigorous coupled-wave analysis (RCWA). Theoretical models also predicted well the transmittance changes as a function of incident angle from 0 ° to 50 ° at a fixed laser wavelength of 5.1 µm. A Fabry-Perot interferometer consisting of two single surface embossed samples is proposed.

Effect of the Preservative Benzalkonium Chloride in Prostaglandin Analogues on Corneal Sensitivity

Purpose: To investigate the effect of a prostaglandin (PG) analogue with or without preservative benzalkonium chloride (BAK) on corneal sensitivity.Methods: Central corneal sensitivity was measured prospectively with a Cochet–Bonnet esthesiometer in patients with normal tension glaucoma (NTG) or primary open angle glaucoma (POAG) before and 1 and 3 months after treatment. All patients began treatment with PG monotherapy with or without BAK preservative.Results: The study enrolled 84 patients: 52 NTG and 32 POAG. The treatment was PG with BAK preservative in 45 eyes and without BAK preservative in 39 eyes. Without BAK, the mean corneal sensitivity was 58.22 ± 3.56, 57.77 ± 4.59, and 56.33 ± 5.47 mm before and after 1 and 3 months, respectively; with BAK the mean corneal sensitivity was 58.20 ± 4.51, 56.31 ± 6.22, and 55.52 ± 6.23 mm. Corneal sensitivity was reduced significantly in patients using PG with the preservative BAK after 3 months (p = 0.033). Co-administration of artificial tears did not affect this reduction in corneal sensitivity.Conclusions: PG with the preservative BAK reduced corneal sensitivity and artificial tears did not improve this reduction. Reduced corneal sensitivity and accompanying side effects should be considered in the long-term use of PG with the preservative BAK.

Pose Tracking of Spacecraft Based on Point Cloud DCA Features

As a key on-orbit service technology, relative measurement of non-cooperative spatial targets can give accurate relative pose for the unmanned rendezvous and docking of non-cooperative targets. With the rapid development of three-dimensional data acquisition equipment such as flash lidar in the field of non-cooperative targets’ pose measurement in recent years, research on the pose tracking technology based on the three-dimensional (3D) point cloud of non-cooperative targets has become more and more urgent. In this paper, we proposed an approach for autonomous recognition and pose tracking of non-cooperative targets based on point cloud features. For this method, the density, curvature and normal angle of a non-cooperative target 3D point cloud are first calculated as the local feature description (DCA) of the point cloud, and then the feature description is used to match and remove errors through RANSAC. Finally the Iterative Closest Point (ICP) algorithm is adopted to obtain the precise pose of the non-cooperative target. Experimental results have shown that this approach can effectively find the features of non-cooperative tumbling targets, get rid of the dependence on the target model and database, and realize the pose tracking of non-cooperative targets.

The accuracy of Infrared sensor detection in asmarttoilet.

Background: Infrared (IR) sensors are useful tools for detecting distance and proximity. However, these sensors are not good at detecting edges of an area, therefore when used in a smart toilet it has difficulty in detecting the orientation and position of the user's body. The aim of this study was to design an IR sensor for a smart toilet with a more accurate and consistent detection. Methods: A total of 12(six men and six women) participants with different body types were involved in this study. IR sensor detection was tested in the sitting and squatting toilets. For the best accuracy, the IR sensor's angle was measured. Red, blue, and red-blue plastic covers were used, as these colors improve precision. The microcontroller was set up to calculate the participant's distance and presence in the cubicle. Results: Toilet positioning varied greatly depending on whether one is sitting or squatting. For sitting toilet, the red cover was close to the accurate distance at a 172° angle. IR detected a man but not a woman's body. The blue cover provided the same best angle of 172° with a higher sensor distance. When the red and blue cover combination was applied, the reading of 141cm detected both men and women, at 172° angle. The actual distance for squatting toilets was 158cm. The optimal angle for both red and blue covers was 176°, however the sensor distance was greater for the blue cover. Finally, the red and blue cover combination gave a more accurate distance of up to 163cm from the actual reading, when detecting both genders at a normal angle of 76°. Conclusion: The combination of red and blue cover gave the most accurate detection for the squatting and sitting toilets. The best angle for sitting was 172°, and for squatting was 176°.

Wide-angle broadband polarization independent bend-able nano-meta absorber employed in optical wavelength

A new wide-angle, bend-able, three-layer nano-meta-absorber (NMA) unit cell structure, consisting of tungsten (W)-silicon dioxide (SiO2)-tungsten (W) for the entire visible spectrum (445 nm–780nm) has been proposed. The NMA has an average absorption of 97.58% and peak absorption of 99.99% has been achieved at 581.3194 nm under a normal incidence angle. This unit cell shows a good impedance match, good capacitive and inductive coupling along with plasmonic resonance features, as well as high electromagnetic (EM) fields with power loss distribution. The design was numerically simulated by the finite integration technique (FIT) and validated with the finite element method (FEM). The proposed NMA can be implemented as a solar energy harvester, optical sensor, light detector, or imaging application.

The Pattern of Occlusal Contact in Lateral Mandibular Jaw Position

Objective: To determine the pattern of occlusal contacts in lateral jaw position of the mandibles in different of molar classification. &#x0D; Study Design: Observational study.&#x0D; Setting: Study carried out at Department of Prosthodontics; Institute of Dentistry, LUMHS, Jamshoro, Pakistan from June 2020 to December 2020.&#x0D; Materials and Methods: Subjects having normal Angle’s class 1 occlusal alignment, both male and females aged between 20-30 years old and subjects having full dentition with the exception for third molars were included the study. While Subjects with severe attrition problems, Subjects were placed in a dental chair with the Frankfurt level parallel to the floor. The interocclusal contacts were recorded with 12μ thick shim stock in four lateral positions on both sides; 0.5, 1, 2, and 3 mm measured with Vernier caliper from the maximum intercuspation point. The shim stock was placed on the occlusal surface on the right side, and the subject was asked to close his/her mandible in the maximum intercuspation position. While a constant pulling force was maintained on the shim stock, the subject was then asked to perform a habitual gliding movement to the right. When the subject’s mandible was moved 0.5 mm right from the intercuspal position, the presence or absence of an occlusal contact were examined and recorded.&#x0D; Results: From 81 patients, the minimum age was found 20 years and maximum age was 30 years with mean and standard deviation of the age was 25.40 ± 2.84 years. Males were 44/81 (54.3%) while females were 33/81 (45.7%). The different lateral positions on right side of tooth of patients at 0.5 mm were 225, 1 mm were 176, 2 mm were 161 and 3 mm were 140. The different lateral positions on left side of tooth of patients at 0.5mm were 197, 1 mm were 171, 2mm were 146 and 3 mm were 123.&#x0D; Conclusion: In the current study, significant association was found between tooth number and first molar tooth lateral position on right side but there was no significant association for other positions and between tooth numbers and different lateral position on left side.

Performance improvement of a desiccant based cooling system by mitigation of non-uniform illumination on the coupled low concentrating photovoltaic thermal units

A Low Concentrating Photovoltaic Thermal system typically employs compound parabolic concentrator to focus sunlight and enhance the quality of both thermal and electrical energy extracted. One of the major issues during this process is the introduction of non-uniform illumination on the photovoltaic panels which can cause hot-spots and significantly reduce both the reliability and the electrical output from this system. This non-uniform illumination can be mitigated by integrating homogenizers which are typically linear extensions to the compound parabolic concentrators profile also referred to as elongated compound parabolic concentrators. In this work, the performance of a 2.5× Elongated Compound Parabolic Concentrator truncated to 1.7× and connected to a desiccant based cooling system has been explored. For a detailed analysis of the system, a coupled 3-D optical, electrical, thermal and process efficiency model has been developed. A full-scale prototype of the modelled system is also fabricated using a 380-Watt peak photovoltaic panel. Experiments conducted on the developed system showed a peak outlet water temperature of 56 °C at a mass flowrate of 24 L per hour. Comparative studies between compound parabolic concentrators and elongated compound parabolic concentrators based low concentrating photovoltaic thermal system is also presented to showcase the overall improvement in the process efficiency due to the mitigation of non-uniformity. Using a 400 mm length of the homogenizer the spatial non-uniformity factor was found to drop from 0.5 to 0.29 under normal incidence angle and results in a rise of 12% in the electrical output when compared to a compound parabolic concentrators-based system. The coefficient of performance of the desiccant-based air-cooling system is found to increase by 50% when coupled with two series-connected elongated compound parabolic concentrators based low concentrating photovoltaic thermal system. The improvement in coefficient of performance is mainly because of thermal and electrical energy savings from the developed system amounting to 352 kWhe/year and 665 kWhth/year, respectively. Further, the mitigation of non-uniform illumination showed a performance improvement of 5% in the coefficient of performance of the air-cooling system compared to a compound parabolic concentrators-based system.

Empirical Modeling of the Global Distribution of Magnetosonic Waves with Ambient Plasma Environment using Van Allen Probes

It is suggested that magnetosonic waves (also known as equatorial noise) can scatter radiation belt electrons in the Earth’s magnetosphere. Therefore, it is important to understand the global distribution of these waves between the proton cyclotron frequency and the lower hybrid resonance frequency. In this study, we developed an empirical model for estimating the global distribution of magnetosonic wave amplitudes and wave normal angles. The model is based on the entire mission period (approximately 2012–2019) of observations of Van Allen Probes A and B as a function of the distance from the Earth (denoted by L*), magnetic local time (MLT), magnetic latitude (λ), and geomagnetic activity (denoted by the Kp index). In previous studies the wave distribution inside and outside the plasmasphere were separately investigated and modeled. Our model, on the other hand, identifies the wave distribution along with the ambient plasma environment—defined by the ratio of the plasma frequency (fpe) to the electron cyclotron frequency (fce)—without separately determining the wave distribution according to the plasmapause location. The model results show that, as Kp increases, the dayside wave amplitude in the equatorial region intensifies. It thereby propagates the intense region towards the wider MLT and inward to L* &lt; 4. In contrast, the fpe/fce ratio decreases with increasing Kp for all regions. Nevertheless, the decreasing aspect differs between regions above and below L* = 4. This finding implies that the particle energy and pitch angle that magnetosonic waves can effectively scatter vary depending on the locations and geomagnetic activity. Our model agrees with the statistically observed wave distribution and ambient plasma environment with a coefficient of determination of &gt; 0.9. The model is valid in all MLTs, 2 ≤ L* &lt; 6, |λ| &lt; 20°, and Kp ≤ 6.

True vertical changes in patients with skeletal class III malocclusion after nonsurgical orthodontic treatment—a retrospective study comparing different vertical facial patterns

Background/purposeRotating mandible backward downward is one of the treatment options in non-surgical skeletal class III malocclusion. The purpose of this study was to compare the true vertical changes after camouflage orthodontic treatment of adult patients with skeletal class III malocclusion categorized by vertical facial type. Materials and methodsThis retrospective study included 27 adult patients (age >18 years) with skeletal class III malocclusion (ANB<1°) who underwent nonsurgical orthodontic treatment at Taipei Veterans General Hospital. The patients were divided into the low-angle (SN-MP<28°), high-angle (SN-MP>36°), and normal-angle (28°≤ SN-MP ≤ 36°) groups according to the original vertical facial pattern. Pretreatment (T1) and post-treatment (T2) lateral cephalograms were superimposed and treatment changes were evaluated. ResultsIn all cases, proper overjet and occlusion were achieved after treatment, and the lower anterior facial height increased with the backward rotation of the mandibular plane. Increase in vertical dimension was the most obvious in the high-angle group, while it was the least obvious in the low-angle group. Extrusion of both the maxillary and mandibular incisors was observed in the high-angle group; however, intrusion of the maxillary and mandibular incisors and decreased overbite were observed in the low-angle group. ConclusionCamouflage orthodontic treatment of skeletal class III malocclusion improves the facial profile by increasing the vertical dimension and clockwise rotation of the mandible. According to our results, patients with a high mandibular plane angle showed better response to vertical dimension increment treatment mechanics than those with low and normal mandibular plane angles.

Simulation of a Centrifugal Pump Based on a Lagrangian Particle Solver

Abstract A three-dimensional full-scale centrifugal pump is simulated using the moving particle semi-implicit (MPS) method. The generic smoothed wall (GSW) boundary is used and extended to three dimensions to address complicated wall shapes and thin-walled structures such as blades in turbomachines. The nonsurface detection technique (NSD) based on conceptual particles is introduced to avoid the loss of the particle-number-density near wall boundaries. A generic approach that can transfer arbitrary CAD models to wall-particle models is established by utilizing the nodal information of the shell mesh. An adaptative resolution technique is proposed by using fine and coarse particles to model the wall boundary with complex geometry. Fine and coarse particles are applied to curved and flat surfaces, respectively, to reduce the computational cost while maintaining high discretizing precision. A criterion based on the normal smooth angle (NSA) is defined to evaluate the local or global precision of established models and provide instructions for refinement. A fully-developed velocity inflow boundary based on 3D inlet rings and pressure outflow boundary based on the moving virtual wall is implemented. Three typical cases including hydrostatic cases with a typical geometry, flow over a two-dimensional backward-facing step, and flow over a three-dimensional tube are tested to verify the proposed models. A particle-based framework to simulate incompressible fluid machines, in which flow fields can be integrally discretized and solved within a single coordinate system, is established. The results are compared with those of the fine volume method and satisfactory agreements are observed.

Computational investigation of various wedges electromagnetic wave absorbers on anechoic chambers

The anechoic chamber is closely related as a device for precisely measuring various acoustic characteristics. Anechoic chambers room conditions controlled to produce a sound field-free space. This study focused on testing various commercial wedges such as Eckel, diamond, pyramidal, and oblique pyramidal. The test was done by varying the elevation of an incident angle at 0°-85° with a stepping distance is 5°. This study is analyzed at 1-3 GHz frequency. This research was conducted based on a computational analysis using the finite element method on electromagnetic wave physics interfaces using COMSOL Multiphysics. The results show that, in general, pyramidal has the best performance. These results are assessed from the stability of absorption performance, the Eckel model obtains -66.6 dB at 1 GHz frequency but on another frequency tests with drastic performance fluctuations. In general, a pyramidal model can be an ideal absorber for anechoic applications because it provides good absorption performance for near normal and normal incidence angles. The results of the design and testing of the wedges model for anechoic are expected to be references in designing the optimal anechoic chamber room. Furthermore, it can contribute positively to tuning acoustic instruments such as microphones or reducing the antenna measurement error.