Ground Versus Soil: A New Paradigm in Geotechnical Engineering Education

me of the practitioners of geotechnical engineering tend to confuse Ground with Soil. It is not just semantics but the terms have d eeper technical and philosophical implications. Soi l is a material which can be handled, felt, seen, sme lt, tasted, and tested in small to medium size samples while ‘Ground’ is an entity that exists in- situ. Just as the adage, ‘The total is more than th e sum of the individual parts’, predicting the behavi or of ground from the so-called properties measured on samples collected from the field is muc h more complex and involves judgment. Ground is an intricate natural entity very similar to ‘Humans’ and exhibits behavioral responses rather than merely possess properties like other en gineering materials. Humans have organs and traits such as being jovial, sad, friendly, angry, misanthropic, etc. but do not have properties. Thei r behavioral responses depend on genetics, environmen t in which they grow, personality they develop and to impetus they experience. Similarly, the genetics of ground is defined by its formation (alluvial, marine, residual, colluvial, a eolin, etc.) depending upon how physiogamy forms the deposit. Ground, one tends to believe, is a sol id mass on which structures are built, becomes suddenly a fluid under specific aggravating circums tances such as consisting loose saturated sand with small amount of fines but subjected to seismic activity of medium to high intensity. On the other hand, a river in flood can erode the ground b y removing particles by its high velocity leading to scour. Slopes on which civilizations thrive, bec ome unstable and sometimes even catastrophic under heavy rainfall, coupled with human activities of deforestation, cutting/steepening of slopes, saturating it by ignorance or callousness, etc. The paper presents a new paradigm that emphasizes the need to visualize Ground, not just as a materia l but rather an entity, and view Geotechnical Engineering comprehensively, beyond a mechanistic s tandpoint

Walking dynamics are symmetric (enough)

Many biological phenomena such as locomotion, circadian cycles, and breathing are rhythmic in nature and can be modeled as rhythmic dynamical systems. Dynamical systems modeling often involves neglecting certain characteristics of a physical system as a modeling convenience. For example, human locomotion is frequently treated as symmetric about the sagittal plane. In this work, we test this assumption by examining human walking dynamics around the steady-state (limit-cycle). Here we adapt statistical cross validation in order to examine whether there are statistically significant asymmetries, and even if so, test the consequences of assuming bilateral symmetry anyway. Indeed, we identify significant asymmetries in the dynamics of human walking, but nevertheless show that ignoring these asymmetries results in a more consistent and predictive model. In general, neglecting evident characteristics of a system can be more than a modeling convenience---it can produce a better model.Comment: Draft submitted to Journal of the Royal Society Interfac

Modelling Ground-Foundation Interactions

Geotechnical practice deals with designing foundations and earth structures. Structure – Foundation –\ud Grou nd interaction is a unique field or topic that concerns both structural and geotechnical engineers. Most geotechnical problems are very sensitive to foundation geometry (length, diameter, spacing), flexural stiffness etc. Even basic parameters such as bearing capacity of shallow foundations, ultimate axial and lateral load capacities of deep/pile foundations, are influenced by the foundation characteristics. More importantly, the serviceability criterion can be satisfied only by proper and rational estimates of structure – found ation – ground interactions. The paper summarizes modelling approaches for foundation – ground interactions, a leaning instability approach for tall structures, and analysis of geosynthetic-reinforced foundation beds

Local canted spin behaviour in Co_1.4-xZn_xGe_0.4Fe_1.2O₄ spinels: a macroscopic, mesoscopic and microscopic study

DC magnetization, neutron depolarization and neutron diffraction (with both polarized and unpolarized neutrons) measurements have been reported for the Co1.4-xZnxGe0.4Fe1.2O4 spinels with x=0.5, 0.6 and 0.7. Neutron depolarization and neutron diffraction measurements confirm the presence of a long range ferrimagnetic ordering of the local canted spins in these ferrite samples. The observed features of low field magnetization have been explained under the framework of thermally activated domain wall movement of ferrimagnetic arrangement of local canted spins. An important role of magnetic anisotropy (due to the presence of Co2+ ions) in establishing the magnetic ordering and domain kinetics in these ferrites has been observed

Triple Band Textile Array Antenna with Enhanced Gain and Low SAR for Off Body Communication Applications

A triple band wearable microstrip patch antenna array has been designed and analyzed in this work. The designed antenna can be operated in ISM, LAES and X-Band with moderate average gain of 4.2 dB. The antenna gain has been improved by constructing array structure of 1X2 and 1X4 with good impedance feeding by quarter wave transformer. The proposed array antennas are providing moderate gain of 5.7 dB (1X2) and 8.3 dB (1X4) with efficiency more than 90% in the operating bands. The antenna model and the array has been constructed on wearable substrate with conductive textile as radiating element in the design for off body wearable communication applications. SAR analysis also providing acceptable values below 1.6 w/kg at triple operating bands with body placement experimentation. &nbsp

Gravitational Collapse of Inhomogeneous Dust in (2+1) Dimensions

We examine the gravitational collapse of spherically symmetric inhomogeneous dust in (2+1) dimensions, with cosmological constant. We obtain the analytical expressions for the interior metric. We match the solution to a vacuum exterior. We discuss the nature of the singularity formed by analyzing the outgoing radial null geodesics. We examine the formation of trapped surfaces during the collapse.Comment: Accepted for publication in CQ

A non-mechanistic perspective of geotechnical engineering

Engineers deal mostly with materials that have unique and specific properties. On the other hand, entities are somewhat like living beings that do not possess unique properties but exhibit behavioral responses to stimuli (actions) . Clays and sands can exist in different state s ranging from liquid to solid and loosest to densest respectively. Responses of soils in general and ground in particular a re examined and analyzed under different test and design conditions. Similarly , the state in which ground exist s can be quantified though the over consolidation ratio. The most commonly used parameter, the undrained shear strength, is sensitive to the manne r in which it is determined . The paper emphasizes the need to visualize soil in the specific sense and ground in a broader perspective as entities rather than as strictly engi neering materials. It is suggested that g eotechnical engineering should be viewed compreh ensively and beyond a simple mechanistic perspective . A unique comparison of ground with a human being elu cidates the concepts enunciated

Knowledge, attitude and practices of antibiotic usage among the medical undergraduates of a tertiary care teaching hospital: an observational cross-sectional study

Background: Social aspect of antibiotic management forms a significant way to overcome the rapidly intensifying problem of antibiotic resistance. Medical students should not only be made aware of the current emerging health issues but also be directed towards rational antibiotics prescribing behavior as future medical practitioners. Aims and objective of the study was to assess the knowledge, attitude and practices (KAP) related to antibiotic usage in second year medical undergraduate students.Methods: The study design was cross sectional, questionnaire based survey. The questionnaire was distributed to a 3rd term and 4th term medical students in their second year of MBBS, to know the KAP regarding antibiotic usage and was assessed by a five point Likert scale and few questions were of true and false type. The data was analyzed by using SPSS.Results: Out of 162 students, 138 (85.19%) participated in the study; 63 (45.65%) were males and 75 (54.35%) were females. 84.06% of the participants known that irrational and indiscriminate antimicrobial use leads to the emergence of resistance. 96.38% agreed that Antibacterial resistance(ABR) was an important and a serious global public health issue and national problem. 71.01% of the respondents were aware that bacteria were not responsible for causing colds and flu. 86.23% said it can lead to more adverse drug reaction.Conclusions: The present survey on antibiotic usage gives useful information about the knowledge, attitudes and practices of second year medical undergraduates, which may be utilized to plan suitable educational interventions that aim at improving the antimicrobial prescribing and use to maximize their effective and efficient use and minimize the development of resistance