Maintenance dredging: allowable limit for dredge volume differences using SBES and MBES datasets / Raiz Razali

In order to ensure channel clearances based on final dredging level are valid, sounding works are required to be used. The dredge volume being excavated is computed using sounding datasets. Although multi-beam echo sounders (MBES) are widely used today because of high-density data, single-beam echo sounders (SBES) are still relevant to be used to calculate dredge volume up to this date. As different hardware generates different data trends and distributions, different software uses various algorithms to calculate dredge volume and also due to different gridding sizes, it can be expected that the results with varying amounts of dredge volume will be generated. However, there is no thorough study on the magnitude of differences in dredge volume that can be established as an allowable limit. Although there are standards that can be used as a guideline, the applicable allowable limit is rarely discussed. This study aims to establish the allowable limit between SBES and MBES in terms of dredge volume calculation. Dredge volume calculation by various methods using different software, which are surface to datum, surface to surface and cross sections generated from SBES and MBES raw dataset, were compared. Five spatial interpolation methods which are inverse distance weighted (IDW), global polynomial interpolation, local interpolation polynomial, radial basis function (RBF), and ordinary kriging were used to grid the area before performing dredge volume computations. The comparative study of dredge volume differences were analyzed to justify the numerical limits in terms of total volumes generated by variable grid sizes, data distributions, cross sections, software, and spatial interpolations based on statistical analysis. The standard deviation result shows that using the allowable level of different limits, the percentage of dredge volume generated in between ± 0.5 to ± 1%

Health Care Poverty

This paper introduces and describes health care poverty. Underinsurance and its consequences for access to health care are highlighted. Definitions of underinsurance and its prevalence are presented. Groups that experience disproportionate barriers to obtaining medical care are identified. Manifestations of underinsurance are explicated and their relationship to receipt of medical care, such as vaccinations and medications is discussed. A refraining of the health care debate is suggested with emphasis moving from uninsurance to access to health care

Exploring Parents Involvement in University Students Education

Educationists has been focusing continuously on importance parental involvement in students’ education. This study was designed to find out parental involvement in curricular and co-curricular activities of university students. The population of this survey research was students studying in universities of Lahore Districts. Random sampling technique was used to collect data of three hundred students from different universities. The researcher constructed a questionnaire for finding out the opinions of students. After the collection of data, the quantitative data were entered in SPSS for analysis about involvement of their parents. The data was analyzed by using frequencies, percentages, means, standard deviations and correlations. Results revealed positive opinions and correlations regarding parental involvement

Phonon Confinement using Spirally Designed Elastic Resonators in Discrete Continuum

Periodic and chiral orientation of microstructures, here we call phononic crystals, have extraordinary capabilities to facilitate the innovative design of new generation metamaterials. Periodic arrangements of phononic crystals are capable of opening portals of non-passing, non-dispersive mechanical waves. Defying conventional design of regular periodicity, in this paper spirally periodic but chiral orientation of resonators are envisioned. Dynamics of the spirally connected resonators and the acoustic wave propagation through the spirally connected multiple local resonators are studied using fundamental physics. In present study the spiral systems with local resonators are assumed to be discrete media immersed in fluid. In this paper it is assumed that acoustic or ultrasonic waves in fluid are propagated along the plane of the spiral resonators and thus only the longitudinal wave mode exists due to nonexistence of shear stress in the fluid. Lagrangian formulation of the spiral systems were employed to obtain the governing Euler-Lagrange equation of the system. Discrete element method was employed to verify the equation assuming nearest neighboring effect

Perception of Fourth Year Medical Students on Task-Based Learning in Clinical Teaching

Background Clinical teaching is always challenging. Different teaching strategies are used for effective teaching and learning in a clinical environment. Task-based learning (TBL) is the teaching strategy where tasks are used for the learning of students. We conducted this study to explore student’s perceptions about Task-based learning. Method This descriptive study was carried out for the academic year 2019-2020 in Shalamar medical college Lahore.TBL taught 4th-year MBBS students during a clinical rotation in Gynae/Obs, and at the end of rotation, they were asked to fill a questionnaire regarding their perceptions about TBL. Results 87 students participated in the study. All the students agreed that TBL is an effective teaching approach, and they have a positive response towards TBL in clinical setting.85%students said TBL improve communication skills, 89.6% Said TBL provide the opportunity of direct encounter with patients, 71.2% find it helpful and informative and 40.2%said that it promotes the active involvement of students. Conclusion: Students found TBL as an effective teaching approach in a clinical setting and find it more advantageous because it involves them more in teaching and learning and help them to improve their communication skills, and provide them opportunities to deal with patients

Wave Propagation in Metamaterial using Multiscale Resonators by Creating Local Anisotropy

Directional guiding, passing or stopping of elastic waves through engineered materials have many applications to the engineering fields. Recently, such engineered composite materials received great attention by the broader research community. In elastic waves, the longitudinal and transverse motion of material particles are coupled, which exhibits richer physics and demands greater attention than electromagnetic waves and acoustic waves in fluids. Waves in periodic media exhibit the property of Bragg scattering and create frequency band gaps in which the energy propagation is prohibited. However, in addition to the Bragg scattering, it has been found that local resonance of artificially designed resonators can also play a critical role in the generation of low-frequency band gaps. It has been found that negative effective mass density and negative effective elastic modulus are created by virtue of the local resonators and are correlated with the creation of the frequency band gaps that can be artificially perturbed. In this paper, the authors present a novel anisotropic design of metamaterial using local split-ring resonators of multiple-length scales. Unlike traditional metamaterials, multiple split rings of different dimensions are embedded in a polymer matrix. Considering the complexity of the proposed material, it is extremely difficult to find the dynamic response of the material using analytical methods. Thus, a numerical simulation was performed in order to find frequency band gaps. Simultaneously, correlation between the band gaps and negative effective mass density and negative effective elastic modulus was verified. Both unidirectional split rings and bidirectional chiral split rings were studied. The effects of discontinuity in the rings at larger scales were compared with the dynamic characteristics of full rings in the proposed metamaterial. Application of such metamaterials will be primarily for vibration isolation and impact mitigation of structures. The proposed configuration is based on unit dimension and is, thus, dimensionless. The concept can be easily commutable between macro-scale structures for low-frequency applications and micro-scale MEMS devices for high-frequency applications

Low Frequency Energy Scavenging using Sub-Wave Length Scale Acousto-Elastic Metamaterial

This letter presents the possibility of energy scavenging (ES) utilizing the physics of acousto-elastic metamaterial (AEMM) at low frequencies (\u3c∼3KHz). It is proposed to use the AEMM in a dual mode (Acoustic Filter and Energy Harvester), simultaneously. AEMM’s are typically reported for filtering acoustic waves by trapping or guiding the acoustic energy, whereas this letter shows that the dynamic energy trapped inside the soft constituent (matrix) ofmetamaterials can be significantly harvested by strategically embedding piezoelectric wafers in the matrix. With unit cell AEMM model, we experimentally asserted that at lower acoustic frequencies (\u3c ∼3 KHz), maximum power in the micro Watts (∼35µW) range can be generated, whereas, recently reported phononic crystal based metamaterials harvested only nano Watt (∼30nW) power against 10KΩ resistive load. Efficient energy scavengers at low acoustic frequencies are almost absent due to large required size relevant to the acoustic wavelength. Here we report sub wave length scale energy scavengers utilizing the coupled physics of local, structural and matrix resonances. Upon validation of the argument through analytical, numerical and experimental studies, a multi-frequency energy scavenger (ES) with multi-cellmodel is designed with varying geometrical properties capable of scavenging energy (power output from ∼10µW – ∼90µW) between 0.2 KHz and 1.5 KHz acoustic frequencies