On the correlation of theory and experiment for transversely isotropic nonlinear incompressible solids

A novel strain energy function for finite strain deformations of transversely isotropic elastic solids which is a function five invariants that have immediate physical interpretation has recently been developed. Three of the five invariants are the principal stretch ratios and the other two are squares of the dot product between the preferred direction and two principal directions of the right stretch tensor. A strain energy function, ex- pressed in terms of these invariants, has a symmetrical property almost similar to that of an isotropic elastic solid written in terms of principal stretches. This constitutive equation is attractive if principal axes techniques are used in solving boundary value problems and experimental advantage is demonstrated by showing a simple triaxial test can vary a single invariant while keeping the remaining invariants fixed. Explicit expressions for the weighted Cauchy response functions are easily obtained since the response function basis is almost mutually orthogonal. In this paper a specific form of the strain energy function for incompressible materials which is linear with respect to its physical parameters is developed. When a curve fitting method is (sensibly) applied on an experimental data, the values of the parameters are obtained uniquely via a linear positive definite system of equations. The theory compares well with experimental data and the performance of the proposed specific form is discussed. A constitutive inequality, which may reasonably be imposed upon the material parameters, is discussed

Feasibility of LoRa Implementation for Remote Weather Monitoring System through Field Measurement and Case Study Analysis

This paper discusses the feasibility of Long Range Wide-area network (LoRa-WAN) implementation for weather data collection and transmission in remote locations, specifically in east Malaysia. Currently, Malaysia Meteorological Department (MetMalaysia) has installed more than 100 weather stations around Malaysia, and out of this number, there are many stations, mostly in east Malaysia that are dependent on Very Small Aperture Terminal (VSAT) services for data transmission due to unavailability of mobile coverage. Due to significant cost of VSAT subscription, LoRa communication is proposed as an alternative solution due to its low power, low-cost, and long range characteristics. In this paper, the study has been performed through two stages; first, technical performance of LoRa network was validated through field measurement in urban areas to determine the actual LoRa characteristics in real condition. In the measurement, a LoRa module operating at 433 MHz was used to demonstrate a single channel LoRa gateway that acted as a bridge to communicate between LoRa node to IP network. Parameters such as received power spectrum and free space path loss were recorded for analysis. Second, based on the measured data, extrapolation of maximum feasible distance of LoRa signal propagation was done to analyze the viability of implementing LoRa in various locations of existing weather stations in Sabah and Sarawak. Two case studies are presented in this paper, with the aim to evaluate the suitable location of LoRa gateway to establish communication with the existing weather stations when LoRa network is used. Detailed link budget analysis was performed for each scenario. Based on the comparison between theoretical and measurement, the power transmitted from LoRa node shows inconsistent readings throughout the day, suspected due to the changes in spread factor that has been automatically set by the module. Nevertheless, taking into account this factor, it was found that the transmission range was adequate for some remote locations. Meanwhile, for some locations that are separated too far from each other, higher power is needed to allow consistent communication

Perbandingan Hasil Belajar Fisika Antara Model Gi Dengan Stad Melalui Metode Eksperimen

This study has a purpose to know: 1) The differences in physics learning outcomes of students’ through cooperative learning GI (Group Investigation) and STAD (Student Teams Achievement of Division) with experimental method. 2) The higher average study result between cooperative learning GI and STAD with experimental method. This study used a quasi experimental design. The instrument to collect data was a test, which consists of 10 questions for 70 students. The results showed: a) There are differences in the study result of students through cooperative learning GI and STAD with experimental method, b)The average study result, which uses cooperative learning GI is more higher than STAD.Penelitian ini bertujuan untuk mengetahui: 1) perbedaan hasil belajar fisika siswa melalui model pembelajaran kooperatif tipe GI (Group Investigation) dan STAD (Students Teams Achievement Of Division) dengan metode eksperimen. 2) rata-rata hasil belajar yang lebih baik melalui model pembelajaran kooperatif tipe GI dan STAD dengan metode eksperimen. Penelitian ini menggunakan Quasi eksperimental design. Alat pengumpul data berupa tes soal sebanyak 10 soal kepada 70 siswa. Hasil penelitian menunjukkan; a) ada perbedaan hasil belajar siswa melalui model pembelajaran kooperatif tipe GI dan STAD dengan metode eksperimen, b) rata-rata hasil belajar yang menggunakan model pembelajaran kooperatif tipe GI lebih tinggi dibandingkan STAD

Estimating the natural and artificial radioactivity in soil samples from some oil sites in Kirkuk-Iraq using high resolution gamma rays spectrometry

The natural and artificial radioactivity in soil samples from some oil sites of Kirkuk-Iraq have been estimated using a gamma spectrometry based on a high purity germanium (HPGe) detector. For this reason, soil samples have been collected from four sites; Henjera, Jabel Boor, Jambor and Qutan. It was found that the specific activity ranged from 7.31 to 63.33 Bq kg−1 for 226Ra, from 3.54 to 42.95 Bq kg−1 for 232Th, from 103.21 to 798.52 Bq kg−1 for 40K and from 0.7 to 9.53 Bq kg−1 for 137Cs. The results have been compared with the worldwide average values. The radium equivalent activity (Raeq), the absorbed gamma dose rate (D), the annual effective dose rate (AEDE), the external hazard (Hex), the internal hazard (Hin) and Gamma radiation representative level Index (Iγ) have also been calculated. The Raeq was 92.173 Bq kg−1, the D was 45.53 nGyh-1, the AEDE outdoor and indoor were 0.0959 and 0.224, respectively, the Hex was 0.242, the Hin was 0.329, and Iγ was 0.680. It has been concluded that no harmful radiation effects have posed to the population who live in the study area. Although, there are some areas where radiation effects have resulted higher than that of the international allowable radiation values

Effect of Material and Thickness of Side Doors And B Pillar on Crashworthiness in Euro NCAP Side Impact Crash Test.

In side impact test which is one out of three tests of Euro NCAP standard, front and rear doors and B pillar are most absorbance parts among vehicle body parts. Passengers are highly in danger while side crash, because of the distance between passenger's head and vehicle body. In this paper effect of material and thickness of doors and B-pillar and their absorbed energy during crash and improvement of its crashworthiness with respect to light weight design are studied using LS DYNA solver. The objective of this paper is to propose a material for doors and B-pillar with a specified thickness to achieve maximum absorbed energy and minimum weight. The shape of the doors and B-pillar remains unchanged and its effect on crashworthiness was not investigated. Parameters which could be changed were material and thickness. Material which studied were steel AISI 1006, aluminum alloy 5182, magnesium AZ31B and high strength steel 204M. For each selected material, five thicknesses were considered and the same initial and boundary conditions according to NCAP were applied. Results show that decreasing in thickness of these parts do not always increase the absorbed energy. In order to reduce the weight and increase the total absorbed energy the best way is to use thinner parts with light material and use a reinforcement bar or foam inside the doors

Effect of Spiral Split Ring Resonator (S-SRR)structure on Truncated Pyramidal Microwave Absorber Design

This paper discusses on the effect of the spiral split ring resonator on the truncated pyramidal microwave absorber. Split ring resonator (SRR) structure can potentially be incorporated onto the truncated pyramidal microwave absorber to increase the reflection loss performance. There are many ways to increase the pyramidal microwave absorber performance. The ways are focusing the new hybrid shapes, using high carbon material, and adding the left handed material structure on the pyramid microwave absorber. Left handed material or metamaterial is an artificial material that does not exist in the real nature like FR4, Taconic, Rogers or RT Duriod.There are many types of left handed material that had been used by several researchers such as split ring resonator (SRR), and photonic band gap (PBG), electromagnetic band gap (EBG) and artificial magnetic conductor (AMC). In this research, spiral split ring resonator (S-SRR) is used to increase the microwave absorber performance. It has the potential to increase the reflection loss or 811 results of the microwave absorber at the several frequencies

Combined effect of local isolate Spodoptera littoralis nucleopolyhedrosis virus and Bacillus thuringiensis on Culex pipiens L. larvae (Culicidae: Diptera)

AbstractA local isolate of Spodoptera littoralis nucleopolyhedrosis virus (SlNPV) showed pathogenicity against Culex pipiens larvae, its long incubation period was broken using a combination between SlNPV and Bacillus thuringiensis subsp. kurstaki (Btk). Laboratory bioassay tests revealed that Culex pipiens 3rd larval instars were susceptible to the applied combination. Data revealed that the addition of Btk generally increased the toxic effect of SlNPV since LC50 decreased from 1.3×103PIB/ml (for SlNPV alone) to 3.6×102 mixed polyhedra and spores/ml (SlNPV-Btk combination), indicating a synergistic ratio of 3.6. LC95 was surprisingly 137-folds dropped as well. The addition of SlNPV generally increased the toxic effect of Btk at a low concentration, where the LC50 outstandingly decreased from 2.5×105spores/ml (for Btk) to 3.6×102 mixed polyhedra and spores/ml (for SlNPV-Btk combination), indicating a synergistic ratio of 6.9×102

Crashworthiness Determination for Front and Rear Doors and B Pillar Subjected to Side Impact Crash by a Mobile Deformable Barrier.

In Euro NCAP standard, adult protection is one of the most important rating scores with 50% weight factor while child protection and pedestrian protection are accounted into consideration with 20% weight factor. For adult protection testing, three tests are required to perform: (1) side impact, (2) pole impact, (3) front impact. In the side impact test, dummy's head, chest, shoulder, thorax, ribs, abdomen, pelvic and femur must be studied to evaluate the rating score. Crashworthiness of a car during side impact can describe the score rated for that car. In this paper the goal is to determine the crashworthiness of side doors and B-pillar in side impact crash test by simulation using LS DYNA software in order to predict required changes to achieve 5 star rating. A model of car has been developed using Hypermesh and CATIA software. A mobile deformable barrier (MDB) model and its honey comp area have been prepared with respect to ECE R95 and Euro NCAP standard. Initial condition such as velocity has been assigned to MDB. Results show that improvement in design in order to increase absorbed energy can probably has positive effect on crash performance as good as using side air bag in order to achieve 5 star rating

KARAKTERISTIK FISIKOKIMIA GELATIN KULIT IKAN AYAM-AYAM ( Abaliste stellaris ) DENGAN PRA-PERLAKUAN KONSENTRASI ASAM SITRAT

Gelatin is a fibrous protein obtained by partial denaturation of collagen. Traditionally, gelatin derived  from mammals’ skins and bones, such as cow and pork. However, both mammals’ gelatin could risk for bovine spongiform encephalopathy (BSE) and foot mouth disease (FMD), besides, gelatin extracted from pork is prohibited in Islam rules. Therefore, fish processing waste is potential as a source of gelatin in terms of starry triggerfish (Abalistes stellaris) skin gelatin. The aims of this study is to characterize physichochemical of gelatin extracted from skin of starry triggerfish. The methods used in this research, experiment with completely randomized design (CDR) by soaking different concentrations of citric acid (0.2; 0.4; and 0.6 M). The results showed that the concentrations of citric acid  had significantly different (P0.05) on the yield, viscosity, gel strength, and fat content of starry triggerfish skin gelatin. On the other hand, the pH, melting point, galling point, protein, moisture, and ash value of starry triggerfish skin gelatin did not perform significantly different (P0.05). The most properties of starry triggerfish skin gelatin meet the commercial gelatin, and it is able to as a potential alternative of halal gelatin

The impact of board diversity on financial reporting quality in the GCC listed firms: the role of family and royal directors

The present study examines the impact of board diversity on financial reporting quality with special consideration of the extent to which family and royal directors influence financial reporting quality (FRQ). The study utilises a sample of 181 listed GCC firms over the period from 2010 to 2016. Board personal attributes, including board expertise, age, gender, and nationality are investigated along with some other board issues such as; board size, meetings, and independence. Panel data analysis with fixed and random effect models are conducted to estimate the results. The results reveal that companies with large board size and greater age have less FRQ. Further, the results report that institutional founders, higher board independence, and expertise associate with greater levels of FRQ. The results also find that board meetings and family founders negatively influence FRQ. However, female directors, foreign directors, and royal board members setting in the board did not contribute to the levels of FRQ in the sampled companies. Finally, the results indicate that companies with a CEO royal member have higher levels of FRQ however, companies with chair board royals have less levels of FRQ. This research has valuable implications for investors, board of directors, analysts, academicians, and policymakers