Load Criteria Research Articles

Topology optimization framework of multiple-phase materials with stress and dynamic constraints under self-weight loads

This work aims to optimize the multi-material structures subjected to self-weight loading for the first time. Ignoring the self-weight loads results in less reliable designs, and to enhance the strength of optimized designs, stress-constrained multi-material topology optimization (MMTO) is considered with body forces. Two stress constraint aggregation schemes are employed and comparable, such as the K-S and p-norm aggregation schemes. Both of these schemes are effective with respect to stress constraints due to local stress issues. Moreover, eigenvalue constraints (MMTO) are introduced in this study with self-weight loading and stress constraints. Thus, the optimized results not only ensure self-weight load criteria but also reduce stress concentration and improve stability due to free vibration of structures. The proposed approach is an alternating-active-phase algorithm (AAPA) for dealing with the problems considered in this work. Results show that the results caused by self-weight loads are totally different from optimized results when they are not considered with self-weight loads using multi-materials.

Study on the dynamic fracture mechanical properties of ultra high-performance concrete under the influence of steel fiber content

Ultra-high performance concrete (UHPC) is characterized by its ultra-high strength and durability, making it suitable for use in large-span bridges, super high-rise buildings, and other special structures. These types of structures often have high requirements for crack control, making the exploration of UHPC's fracture mechanics properties of significant importance. Therefore, this paper sets up four steel fiber contents (0 %, 0.6 %, 1.2 % and 1.8 %) and four strain rates (10−5/s, 10−4/s, 10−3/s and 10−2/s), totaling 16 working conditions. The hydraulic servo system combined with digital image correlation (DIC) technology was used to conduct fracture mechanics tests on UHPC three-point bending beams. The test results show that the unstable fracture load of UHPC increases with the increase of strain rate and steel fiber content, and increasing the steel fiber content can enhance the strain rate effect of UHPC to a certain extent. Additionally, combined with the J-criterion model, this study proposed a dynamic criterion for the unstable fracture load of UHPC considering the influence of steel fiber content. The initial fracture toughness, unstable fracture toughness, and fracture energy of UHPC are significantly more affected by steel fiber content than by strain rate. Through DIC technology, the analysis of UHPC crack propagation shows that UHPC without steel fibers experiences rapid crack expansion in the Pre-90 % to Peak stage, with less influence from the strain rate. However, UHPC with steel fibers exhibits a more uniform crack growth rate, with the crack emergence phase gradually lagging as the strain rate increases. For UHPC without steel fibers, the crack opening displacement (COD) at the unstable fracture load point surges suddenly, while the COD development in UHPC with steel fibers is slower. At lower strain rates, an increase in steel fiber content leads to an earlier sudden increase phase in UHPC's COD; at higher strain rates, the influence of steel fiber content on the sudden increase phase of UHPC's COD is more scattered. The research results of this paper provide a theoretical basis for the calculation and analysis of the dynamic response of UHPC structures under seismic loads.

Fatigue prediction and optimization of laser peened turbine blade using artificial neural networks and ANFIS

AbstractThis paper investigates the fatigue behavior prediction of Ti‐6Al‐4V thin‐leading‐edge turbine blade specimens treated with laser shock peening (LSP) using two advanced artificial intelligence (AI) methods: artificial neural networks (ANNs) and adaptive network‐based fuzzy inference system (ANFIS). The study aims to estimate the endurance under high cycle loading conditions. First, using ABAQUS and MATLAB software, the modified Crossland criterion for uniaxial loading is applied to recalibrate endurance limit values based on modifications induced by the LSP process. Then, these techniques are employed to predict the modified Crossland criterion profile and endurance limit values influenced by the LSP treatment. Specifically, numerical values are used as training and testing data for these AI models. As a result, these AI methods provide highly accurate prediction and optimization of the modified Crossland criterion and endurance limits, demonstrating their reliability and effectiveness.

Investigation of the Overall Damage Assessment Method Used for Unmanned Aerial Vehicles Subjected to Blast Waves

With the aim of investigating the assessment methodology for the overall damage effects on an unmanned aerial vehicle (UAV) subjected to a blast wave, the failure criteria for the typical UAV was formulated through an analysis of the structural strength design standards. Specifically, the shear force associated with wing failure can serve as a critical parameter for assessing the overall damage inflicted on the UAV by blast waves. According to the design load criterion of the aircraft, the shear force value corresponding to the overall failure of the typical UAV was calculated. Numerical simulations were conducted to investigate the mechanical response of UAV structures under blast wave loading generated by a 500 g explosive. Combining the critical shear force values obtained from theoretical calculations with the numerical simulation results, two distances between the explosives and the UAV that could produce different damage effects were estimated, namely 1 m and 2.5 m. Subsequently, static explosion experiments with equivalent explosive charges were performed, revealing different damage effects on a typical UAV at two specific distances. The numerical simulation results were highly consistent with the experimental observations, further validating the scientific and rational basis for using shear force as a primary parameter in assessing overall structural damage to fixed-wing UAVs.

Esthetically driven immediate provisionalization in the anterior zone: 5-year results from a prospective study evaluating 3.0-mm-diameter tapered implants

ObjectivesEvaluate the 5-year safety and efficacy of a narrow-diameter (3.0 mm) implant that was immediately provisionalized with a single crown in the maxillary lateral incisor or mandibular central or lateral incisor area.Materials and methodsAn open, prospective, single-cohort, multicenter study was conducted, in which narrow-diameter implants were placed in fresh, healed extraction, or congenitally missing sites. All patients were required to meet strict criteria for immediate loading. The primary endpoints were marginal bone levels (MBL) and MBL changes (MBLC) from implant placement to 5-year follow-up. Secondary endpoints included cumulative 5-year survival and success rates, soft tissue health, and esthetic parameters.ResultsA total of 91 implants were placed in 77 patients. The mean MBL remained stable from the 1-year (− 0.79 ± 0.73 mm, n = 75) to 5-year (− 0.74 ± 0.87 mm, n = 65) follow-up. A marginal bone gain of 0.11 ± 0.83 mm was observed from the 1-year to 5-year follow-up. The cumulative 5-year survival rate was 96.5%, and the cumulative 5-year success rate was 93%. The clinical parameters, including the modified plaque index, modified sulcus bleeding index, Jemt’s papilla index, and pink esthetic score improved throughout the 5-year study.ConclusionsThe study demonstrated that narrow-diameter implants represent a safe and predictable treatment option for subjects suitable for immediate loading and with limited bone volume or limited inter-dental space.Clinical relevanceNarrow-diameter implants with immediate provisionalization can be considered for use to restore missing or damaged teeth with predictable functional and esthetic outcomes. This trial was registered with ClinicalTrials.gov (NCT02184845).

Prosthodontic criteria for maxillary immediate occlusal loading, surgical classifications of atrophic maxillae, and presentation of a new implant/anatomic classification system for immediate maxillary rehabilitation.

Immediate full-arch occlusal loading for patients with atrophic edentulous maxillae satisfies critical needs for this specific type of edentulous patient after placement of implants with high levels of primary implant stability. The needs include improved aesthetics, limited immediate improved function, and elimination of removable prostheses. Classification systems exist for edentulous maxillae but they do not include specifics regarding posterior implant placement. In conjunction with anterior implants, posterior implants improve Anterior/Posterior (A/P) spreads, decrease cantilevered segments (CLs), and likely will improve implant and prosthetic success rates. The purposes of this article include presenting a new classification system that outlines the different types of implants now available which will likely achieve the requisite primary stability for immediate fixed rehabilitation. This proposed classification system identifies a relationship between different implant options currently available and the remaining quantity of bone in the first and second maxillary molar zones. The available literature regarding current classification systems was reviewed. The benefits and limitations of each system were described. The parameters associated with Immediate Occlusal Loading (IOL) for full arch maxillary prostheses include: posterior cantilever lengths of full arch fixed prostheses; existing A/P spread considerations for full arch prostheses; and introduction of a new classification system for atrophic posterior maxillary edentulous ridges were identified. Currently, there are no available classification systems that outline specific implant options for posterior maxillae which will likely achieve the minimum primary stability needed for immediate rehabilitation. A new classification system was proposed where the rationale was to show clinicians that when a certain amount of bone remains in the posterior maxilla, there are specific implants designed to maximize primary stability. High implant primary stability is required for rehabilitation with immediate fixed implant-supported provisional prostheses. The proposed classification system assists clinicians in understanding what implant geometry is available and can be expected to achieve the requisite primary stability for immediate occlusal loading based on the available bone in the posterior maxillary molar zone. This article reviewed current classification systems for edentulous maxillary patients, as well as clinical parameters required for full arch, immediate occlusal loading. It also presented a new classification system to assist clinicians in selecting appropriate implants and surgical techniques for immediate fixed rehabilitation of patients with atrophic maxillae.

A strain components-based Mohr–Coulomb fracture criterion for proportional loading

Ductile fracture criteria are crucial in the application of elastoplastic materials like advanced high-strength steels, particularly due to their tendency to fail without significant localized necking. It is aimed to figure out the unified mechanism for ductile fracture and accurately describe it with phenomenological criteria. In this study, the effect of the stress triaxiality and the Lode parameter is analyzed mathematically. The maximum shear strain and the normal strain to fracture are emphasized in the proposed strain components-based Mohr–Coulomb fracture criterion particularly designed for plane stress states, and it is assumed that fracture occurs when the combination of the maximum shear strain and the normal strain reaches the critical value. It is then extended to describe fracture with the equivalent plastic strain and the normal strain to fracture. The experimental fracture data of AA 2024-T351 and the additively manufactured Ti-6Al-4V titanium alloy are used to verify the proposed models. A fracture forming limit diagram comprising forming limit curves calibrated from stress states under different stress triaxialities is proposed based on the proposed fracture criteria for plane stress states. This study shows that a strong correlation between the maximum shear strain and the normal strain to fracture has been observed, and it can be described piecewise-linearly. Besides, the orientation of the fracture surface under both tension (including plane strain tension) and compression (including plane strain compression) can be qualitatively explained by the Mohr’s strain circles. The results provide a new insight into the intrinsic deformation and fracture mechanism of materials that fail without severe localized necking.

Fatigue and monotonically-loaded reinforced concrete specimens subjected to partial area loading

The degradation of concrete structures is often due to the continuous application of compressive fatigue loads. Understanding of concrete behaviour in different environmental conditions and under especial fatigue loading arrangements, particularly in cases where the loaded area is smaller than loaded element, herein referred to as partially loaded area, is of utmost importance to make a realistic prediction of the concrete fatigue life for a reliable design of civil engineering infrastructure. This paper focuses on investigating the fatigue performance of reinforced concrete specimens subjected to partially loaded areas, considering the influences of steel fibres, reinforcement arrangement, and the environmental factor of water submergence. A typical example of a partially loaded concrete component subjected to fatigue loading is circular spread footings used as concrete foundations for typical wind turbines. In these types of elements, the compressive strength of the concrete can be enhanced due to the confinement provided by way of lateral restraint stemming from surrounding concrete and reinforcement. However, design codes primarily address static loading and lack specific criteria for fatigue loading in these partially loaded regions. To address this research gap, results from a comprehensive experimental study, which in total included 111 concrete specimens subjected to monotonic loading and 25 specimens tested under cyclic loading, were used to study this problem. The investigation aimed to evaluate the effects of steel fibres and reinforcement arrangement on both static and fatigue capacity. Additionally, the impact of submerging concrete structures in water on their fatigue performance was examined, revealing a decrease in their fatigue life. The experimental results demonstrated that the presence of steel fibres and splitting reinforcement significantly increased both static and fatigue capacity. Most current design codes neglect the environmental factor of water submergence, leading to reduced fatigue capacity in concrete structures. Consequently, the validity of the design codes DNV-OS-C502 and fib Model Code 2010 was evaluated, and a new environmental factor for partially loaded areas subjected to cyclic loading is proposed. To evaluate the experimental results and understand the mechanical response, nonlinear finite element analyses were conducted using a smeared-crack continuum modelling procedure coupled with high cycle fatigue material models to assess its applicability for estimating fatigue performance of partially loaded reinforced concrete elements. It was found that a plane stress modelling procedure was capable of estimating fatigue capacity for dry concrete components, however, overestimated the fatigue capacity of wet concrete components.

Development and field evaluation in African and Asian countries of an hepatitis B virus PCR on open polyvalent platforms to determine treatment eligibility: results from the “Agence Nationale de Recherche sur le Sida et les hépatites” 12327 study

ObjectivesWidespread testing and treatment are essential to eliminate hepatitis B virus (HBV) infection as a public health concern. However, in resource-limited countries, access to HBV PCR is limited. In this study, we developed a quantitative HBV PCR assay on open molecular platforms and evaluate its performance in diagnosing clinically significant HBV DNA thresholds as defined by the WHO (2000 IU/mL, 20 000 IU/mL, and 200 000 IU/mL). MethodsWe implemented our HBV PCR test in seven African and Asian countries and France, using either an in-house laboratory method or a European conformity for in vitro diagnostic (CE-IVD) marked version of the PCR (Generic HBV Charge Virale, Biocentric). Results were compared with reference tests (Roche Cobas AmpliPrep/Cobas TaqMan and Abbott RealTime on Abbott m2000). ResultsThere was a good agreement between the HBV DNA results of 1015 samples tested by the PCR on open polyvalent platforms and the results from reference tests (mean difference (bias ± standard deviation [SD]): −0.3 ± 0.7 log10 IU/mL and −0.2 ± 0.9 log10 IU/mL when compared with Roche and Abbott tests, respectively). Kappa-Cohen agreements between the HBV PCR on open polyvalent platforms and the Roche/Abbott assays appeared almost perfect for HBV DNA levels ranged from >20 000 to 200 000 IU/mL and >200 000 IU/mL, substantial and moderate for HBV DNA levels ranged from 2000 to 20 000 IU/mL when compared with Abbott and Roche, respectively. The assay's performance was consistent across genotypes A, B, C, D, and E. DiscussionThis field evaluation showed that our HBV PCR test is a valuable alternative to proprietary PCR systems. PCR assays on open platforms contribute to expanding clinical laboratory solutions for diagnosing individuals who meet the viral load criteria for antiviral therapy (>20 000 IU/mL) and mother-to-child prophylaxis (>200 000 IU/mL).

A Test System for Transmission Expansion Planning Studies

This paper introduces a 17-bus 500 kV test system intended for transmission expansion planning (TEP) studies. The overhead lines used in the system are based on an actual 500 kV transmission line geometry. Although several test systems have been developed for various forms of power system analysis, few are specifically tailored for TEP studies at the transmission voltage level, as opposed to the distribution voltage level. Current test systems for TEP studies are limited to single loading conditions only for normal operating conditions, and the majority of these systems are intertwined with issues related to the energy market or devised specifically for integrating new generations and loads into the existing power systems. However, ensuring a test system satisfies both voltage drop and line loading criteria during both normal and all single contingency operations is crucial in TEP studies, and addressing these issues under contingency conditions poses notable challenges. Moreover, practical TEP scenarios involve varied loadings, including peak load and dominant loading (60% of peak load) scenarios, while the existing test systems are configured solely for single loading conditions. To address these technical gaps, this paper introduces the 17-bus test system operating at a transmission voltage level of 500 kV, meeting technical requirements under normal and all single contingency operations for both peak load and dominant load scenarios. Detailed specifications of the proposed test system and load flow analysis at both normal and contingency conditions for different loading conditions are presented. This test system serves as an invaluable resource for TEP studies.

Flexural Capacity Criteria for Load And Resistance Factor Rating of Shallow Covered Corrugated Metal Culverts

Departments of transportation are required to inspect and rate bridges that span more than 20 ft (6.1 m). One frequent challenge is rating shallow-buried corrugated metal culverts, since there are no standard methodologies deemed applicable to all sections and depths for defining the resistance when moment or combined moment and thrust controls. The commonly used Culvert ANalysis and DEsign (CANDE) finite element software was developed specifically for culvert design; its companion program, CANDE Tool Box, enables computing of load rating factors. However, owing to nonlinearities associated with soil–structure interaction and yielding of the corrugated cross-section, extracting accurate representations of available resistance for shallow-buried corrugated metal culverts may require a cumbersome iterative procedure. Furthermore, the resulting rating factor from not properly implementing nonlinear procedures may indicate an available resistance that is unconservative from a safety perspective. Recent improvements adopted by AASHTO and incorporated into CANDE include combined thrust–moment criterion, but are deemed suitable only for culverts with deep corrugation cross-sections. The objective of this research was therefore to assess flexure criteria for load rating shallow-buried corrugated metal pipe and arch structures, including standard corrugation cross-sections, to simplify the process without significantly sacrificing accuracy. Challenges with available methods and recently implemented combined criterion for the shallow-buried culvert scenario are first discussed. A modified flexural capacity criterion based on load and resistance factor rating is then developed and presented. Finally, the accuracy and applicability of the methodologies are assessed using a range of practical corrugated metal culvert dimensions and parameters.

Hysteretic model of seawater and sea sand concrete-filled FRP- steel composite tube columns considering the confinement effectiveness

Aiming at the problems of marine infrastructure facing corrosion and complex load environments, a seawater and sea sand concrete-filled CFRP- steel composite tube (SFSCT) column structure was proposed: CFRP sheets are pasted on the inner and outer walls of the steel tube to provide corrosion resistance and improve yield capacity, and then the environment-friendly seawater and sea sand concrete is used to fill the steel tube. Based on pseudo-static tests, a fiber model was established based on OpenSEEs. The axial compression ratio, steel tube thickness, yield strength, shear span ratio, and CFRP layer were analyzed and collected as a database. The influence rules of the designed parameters were obtained. Combining experimental data and fiber model results, a complete hysteretic model was finally proposed based on the equal ratio superposition of parameters. The proposed model includes the parameter prediction methods such as peak load, drift ratio, and stiffness of the descending section, as well as the loading and unloading criteria. A trilinear skeleton curve model was established to predict the developing trends of various parameters. The confinement effectiveness of steel and CFRP was fully taken into considerations in the proposed model. The predicted results are in good agreement with the simulation results of SFSCT.

Increasing the Competitiveness of MSMEs in the Global Market by Integrating Digital Marketing and Environmental Awareness: Case Study of the Implementation of Green Environmental Awareness and Green Product Pricing and Its Impact on Green Product Purchasing

This research aims to increase the competitiveness of MSMEs in the global market by integrating digital marketing and environmental awareness: a case study of the application of green environmental awareness and green product pricing and its impact on green product purchasing. This type of research is quantitative with a cross-sectional approach. The population in this study is all MSMEs assisted by the green-based DKI Jakarta Industry, Trade, Small and Medium Enterprises Cooperative which amounts to 284 MSMEs. The sampling technique used is cluster random sampling. Determination of the sample size using the Generic formula so that the sample obtained amounted to 164 respondents. The main research instrument used was a questionnaire with Likert Scale. The data analysis technique used is Confirmatory Factor Analysis Second Order to determine the value of each instrument factor used with standardized factor loading and t-value criteria. The accepted value in the test was more than 0.5 for standardized factor loading and more than 1.96 for t-value. Structural model analysis is carried out using Struqtural Equation Modeling (SEM). The analysis process was carried out using Lisrel with fit model criteria, namely chi square, GFI, AGFI, NFI and CFI, PNFI, and AIC. The results of the analysis show that there is a direct influence of green marketing on green product purchasing. There is a direct influence of green environmental awareness on green product purchasing. There is a direct influence of green product pricing on green product purchasing. There is a direct influence of green marketing on green environmental awareness. There is a direct influence of green environmental awareness on green product pricing

Comparing the efficiency of strengthening timber beams reinforced with carbon composite rods and plates

This study reports the results of experiments comparing the effect of structural reinforcement for timber beams strengthened with different carbon composite materials. Samples of one series were strengthened by gluing a carbon fiber plate from the outside to the face of the beam. The samples of the other series were strengthened by laterally gluing two carbon fiber rods inside the beam. According to the bending research program, the ultimate loads and deflections were determined for both series. As a result of the analysis of the results and comparison with unreinforced samples from the control series, the effect of beam reinforcement and the model of their destruction were determined. Studies have shown that the effect of external reinforcement with a plate was 86.7 % according to the criterion of full failure load, 20.5 % according to the criterion of ultimate load, 13.4 % according to the criterion of ultimate deflection. The effect of rod reinforcement was 48.6 %, 18.6 %, and 4.1 %, respectively. The theoretical analysis of the results showed a convergence of up to 8.2 % with the experimental results. External reinforcement with a plate compared to lateral gluing of rods showed better results due to the placement of the plate in the zone of maximum tensile stresses. This arrangement more effectively limited the spread of ultimate stresses and the development of cracks. The reinforcement parameters of the samples (materials, placement, percentage of reinforcement) were selected under the condition of the same theoretically predicted bearing capacity after reinforcement. However, comparative experimental studies have revealed differences in the processes of deformation and destruction of reinforced beams. The results will contribute to making rational project decisions and for choosing a relevant technique of strengthening timber beams with carbon composite materials

Parametric optimisation on the performance of the journal bearing using Taguchi approach

Hydrodynamic journal bearings are widely used to support high-speed rotating equipment due to their excellent strength and load-bearing capacity. Therefore, bearings are essential mechanical elements to improve the quality of rotating equipment. Bearing performance depends on various factors but pressure and frictional torque plays a vital role in load carrying capacity of bearing. In this present work, both experimental and analytical approach of a typical journal bearing has been carried out to determine the optimal performance of the bearing. Taguchi-based optimisation method has been proposed for journal bearing. Taguchi L27 orthogonal array has been planned to study peak pressure and frictional torque with three input parameters speed, load and viscosity index. The result shows that loading criterion influences much on performance of bearing. The experimental data is obtained from a journal bearing test rig and the analytical data are generated by MINITAB 18. From the experiment, it can be confirmed that speed – 2000 rpm, load – 600 N and viscosity index – 150 are the ideal process parameters for lower peak pressure and less frictional torque.

Quantitative assessment on synchronisation capability of a line‐start permanent magnet synchronous motor with hybrid rotor

AbstractThe authors devote a quantitative assessment on the synchronisation capability of a line‐start permanent magnet synchronous motor (LSPMSM) equipped with a hybrid rotor. The quantitative assessment is realised by determining a load criterion consisting of load torques and inertias under which the motor will just synchronise. During the process of load‐criterion determination, close attention is paid to parameters governing the motor synchronisation behaviour. Following the principle of stator‐current error minimisation, the time‐variant magnetising inductances and permanent magnet (PM) flux linkages of the analysed LSPMSM are simplified into slip‐dependent constants via the simple and robust genetic algorithm (GA). The load criterion is then obtained after the establishment of a dynamic motor model involving the simplified parameters. Prototyping tests focused on motor speed‐time responses under different mechanical loads are carried out to validate the obtained load criterion and the paper analyses.

Behaviour of recycled aggregate concrete-filled stainless steel tubular columns subjected to lateral monotonic and cyclic loading

This paper presents a series of experimental research on recycled aggregate concrete-filled stainless steel tubular (RAC-FSST) columns subjected to lateral monotonic and cyclic loading. The influence of axial load level, shear span ratio, and replacement ratio of recycled coarse aggregate on the RAC-FSST members under compression-bending loads is studied. The test results indicate that the RAC-FSST columns exhibit favorable ductility and energy dissipation capacity. The P-Δ skeleton curves of the columns subjected to lateral cyclic loading are similar to those of columns under monotonic loading. It indicates that, compared with the plastic damage of the concrete, the cyclic hardening characteristics of the stainless steel have more significant influence on the bearing capacity. Considering the characteristics of material loading and unloading criteria, a FE model is established to analyze the seismic performance of RAC-FSST, with the internal force development and stress distribution discussed. Based on the parametric analysis, the modification method of bearing capacity and the hysteretic models of RAC-FSST members are proposed.

Structural-equivalent mean recurrence intervals for NESC Rule 250B

Overhead lines in the United States are currently designed based on both deterministic and probabilistic loading concepts for ice and wind. These load cases are specified in the National Electrical Safety Code (NESC) (Institute of Electrical and Electronics Engineers, Inc. (IEEE), 2023). The deterministic loads for the continental United States are based on three loading districts: light, medium, and heavy, and the corresponding loads based on the specified weather criteria are to be used with specified structural load factors. In practice, the factored deterministic loads often control the design of a structure compared to the probabilistic loads which apply a load factor of 1.0. Furthermore, the deterministic loads are not associated with a Mean Recurrence Interval (MRI), thereby making the assessment of the reliability index cumbersome for structures controlled by these loads. A method to determine an equivalent MRI for these deterministic loads is presented, which involves associating the factored deterministic loads with a probability of exceedance based on location for ice and wind loads. The method is applied to a 230 kV transmission line including seven structure types and line angles, and for 26 locations across the continental United States, and a comparison of the equivalent MRI based on the deterministic loads is made to the probabilistic loads. Trends are presented which illustrate that the resulting equivalent MRI vary significantly among location and structure types. The findings highlight that different structure types of the same transmission line are associated with a wide range of equivalent MRI. Discussion is provided on the trends observed in case study and the inconsistency in structural reliability that could result from the application of deterministic ice and wind load criteria in NESC Rule 250B. It is not the intent of this paper to state what design MRIs are needed to ensure adequate reliability. The intent of this paper is to determine what range of structural equivalent MRIs overhead lines in the United States are currently designed to withstand.

Application of Photojournalistic Code of Ethics to Legal and Criminal News at Tribun Bone

This study discusses the application of the photojournalism code of ethics to legal and criminal news in Tribun Bone. The objectives of this study are (a) to determine the criteria for journalists in publishing photojournalism on legal and criminal news in Tribun Bone, (b) to identify efforts to apply the code of ethics for photojournalism on legal and criminal news in Tribun Bone, and (c) to analyze What obstacles do Tribun Bone journalists face in publishing photojournalism on legal and criminal news in Tribun Bone? The type of research using qualitative descriptive with data sources is journalists in the field of law and crime rubrics and the person in charge of Tribun Bone. Data collection techniques by observation, interviews, and documentation. Data analysis uses Miles and Huberman analysis, which consists of three stages, namely data reduction, data exposure and conclusions. The results showed that, 1) The criteria for photojournalism loading on legal and criminal news in the Bone Tribune are, photojournalism must appear as it is, photos obtained in the field must be sterile from excessive editing . It is done for the sake of validity and honesty of information. If the immoral victim takes it from behind so that the victim's face is not visible, if his face is visible then at the time of loading his face must be blurred. 2) Tribun Bone already understands the existing photojournalism code of ethics and has been implemented in accordance with the code of ethics, but there are still errors from the party The Bone Tribune where some of the news is published still shows the face of the perpetrator of the crime. 3) The first obstacle faced was that it was difficult to obtain photos if not at the time of press release because of limited access for journalists to get images. Second, the lack of communication between journalists at the Bone Tribune, then the third is negligent, forgetting the ethics of existing photos , it is done to compete to provide good news. warmest to the audience.

Hypoplastic model with an inner memory surface for sand under cyclic loading

We propose a hypoplastic model for granular soil using the memory surface notion to consider the stress history. This paper aims to resolve the limitations of the hypoplastic model that are rooted in the neglected memory impacts. First, we make use of the intergranular strain concept in conjunction with a reference hypoplastic model to present a simple model accounting for cyclic loading. Further, by integrating the memory concept into the hypoplastic model using intergranular strain, we present a new hypoplastic model that can recall the strain and stress history. The memory surface is derived from the constitutive model employing a definition of dissipation energy. The loading criterion based on the dissipation surface improves the model’s performance in predicting cyclic loading. Finally, the performance of our models is compared based on laboratory tests.