Physical Origins of Universal Mobility in MOSFET Inversion Layers: Conservation Laws

The salient properties of charge flow (or current) along the MOSFET’s inversion layer are shown to be consilient with a river’s flow in a gravitational potential field, insofar as both are fundamentally governed by energy conservation principles, and their laminar and turbulent conditions determined by friction losses at shallow depths. We establish analytically that the low-field, "universal" effective mobility, μ_eff<b>, </b>long reported to vary as ~(E*_T)^-1/3 for transversal fields below 0.5 MV/cm, is manifestation and consequence of both energy and momentum conservation under laminar flow conditions and quantum mechanical effects, in which case the inversion layer’s mean thickness also varies as ~(E*_T)^-1/3 up to a maximum value E*_T ≈ 0.35 MV/cm at 300K, determined only by interface "terrain" amplitude and fundamental constants.

Wall Pressures In a Channel Flow Obstructed By a Line of Inclined Rods: Invariant Groups and Semi-Empirical Correlations

An experiment is conducted in a rectangular channel obstructed by a transverse line of four inclined cylindrical rods. The wall pressure around the perimeter of a central rod and the pressure drop through the channel are measured varying the inclination angle of the rods. Three assemblies of rods with different diameters are tested. The measurements were analyzed applying momentum conservation principles and semi-empirical considerations. Several invariant dimensionless groups of parameters relating the pressure at key locations of the system with characteristic dimensions of the rods are produced. It was found that the independence principle holds for most of the Euler numbers characterizing the pressure at different locations, that is, the group is independent of the inclination angle provided that the inlet velocity projection normal to the rods is used to non-dimensionalize the pressure. The resulting semi-empirical correlations can be useful for designing similar hydraulic units.

Physical Origins of Universal Mobility in MOSFET Inversion Layers: Conservation Laws

The salient properties of charge flow (or current) along the MOSFET’s inversion layer are shown to be consilient with a river’s flow in a gravitational potential field, insofar as both are fundamentally governed by energy conservation principles, and their laminar and turbulent conditions determined by friction losses at shallow depths. We establish analytically that the low-field, "universal" effective mobility, μ_eff<b>, </b>long reported to vary as ~(E*_T)^-1/3 for transversal fields below 0.5 MV/cm, is manifestation and consequence of both energy and momentum conservation under laminar flow conditions and quantum mechanical effects, in which case the inversion layer’s mean thickness also varies as ~(E*_T)^-1/3 up to a maximum value E*_T ≈ 0.35 MV/cm at 300K, determined only by interface "terrain" amplitude and fundamental constants.

Conservation Laws at Physical Origins of Universal Mobility in MOSFET Inversion Layers in Consilience with River Flow in a Gravitational Field

The salient properties of charge flow (or current) along the MOSFET’s inversion layer are shown to be analogous to a river’s flow in a gravitational potential field, insofar as both are fundamentally governed by energy conservation principles, and their laminar and turbulent conditions determined by friction losses at shallow depths. We formulate an accurate model for a non–uniform mobile charge density giving rise to a mean potential<i> </i>across an inversion layer of finite extent<i>,</i> which we measure by a sensitive experimental method …

Conservation Laws at Physical Origins of Universal Mobility in MOSFET Inversion Layers in Consilience with River Flow in a Gravitational Field

The salient properties of charge flow (or current) along the MOSFET’s inversion layer are shown to be analogous to a river’s flow in a gravitational potential field, insofar as both are fundamentally governed by energy conservation principles, and their laminar and turbulent conditions determined by friction losses at shallow depths. We formulate an accurate model for a non–uniform mobile charge density giving rise to a mean potential<i> </i>across an inversion layer of finite extent<i>,</i> which we measure by a sensitive experimental method …

Earthen architectural heritage in the international context: values, threats, conservation principles and strategies

PurposeThis research aims to highlight the values, principles and recommendations for conservation in order to establish valid strategies for the conservation of earthen built heritage. This is done following a methodology which uses indirect (bibliography) and direct (case study) sources systematically analysed from different perspectives: the values of Earth as a material and of architectural and vernacular heritage; the heritage conservation principles found in international documents; and the analysis of over 3,000 case studies from which good practices in earthen architecture conservation are extracted.Design/methodology/approachEarthen built architectural heritage is found widely in all parts of the world, in archaeological sites and monumental and vernacular architecture, which research centres and researchers are increasingly studying and cataloguing. However, despite its richness and historic and cultural values, as well as its many merits in environmental sustainability, sociocultural and socio-economic terms, the value of this heritage has not been fully recognized in fields with major repercussions in conservation.FindingsFinally, these data are cross-referenced to establish the broadest possible strategies to guarantee all aspects to be taken into account in the conservation of earthen built architectural heritage.Originality/valueThe text provides an overview of the different methodologies in order to extract specific strategies applicable to the conservation of this heritage, both locally and globally.

Agroforestry development in Lake Toba catchment area: Farmer’s perception and interest

The Lake Toba Catchment Area (LTCA) has degraded due to a lack of implementation of conservation principles. Agroforestry is one of the land-use techniques with a conservation approach. Agroforestry development in LTCA should be supported by stakeholders, especially farmers. Farmers’ support will be formed if they have a good perception and interest in developing the agroforestry systems. The study aims to determine farmers’ characteristics, perceptions, and interests in agroforestry development in LTCA. The study was conducted from July until August 2019 at Simalungun Regency, North Sumatra Province. Data were collected through semi-structured interviews using a questionnaire with 30 respondents. Measurement of farmers’ perception and interest use a Likert scale. The data were then analyzed descriptively. The results showed that the farmers’ age is dominated by the productive phase (30-50 years old); they are only completed elementary schools, with average landholding was <0.3 ha, and farming experience >10 years. Farmers’ perceptions and interests in agroforestry development in LTCA are in good categories, each with a score of 4.18. These perceptions and interests of farmers are supporting factors that would positively impact the development of sustainable agroforestry in LTCA.

Physical Exercise Reduce Fatigue in Children With Leukemia

Fatigue is a complaint that many children with Acute lymphoblastic leukemia (ALL) feel while undergoing chemotherapy and is a multidimensional problem. The condition of fatigue that children continuously feel requires treatment from health workers. To optimize physical exercise interventions, researchers combined physical exercise with Levine theory based on four conservation principles to increase patient activity during treatment. The goal of the study was to provide physical exercise to children with ALL undergoing chemotherapy. The research method is quantitative with Quasy Experimen With Control Group Pre-Test-Post-Test Design. This study sample of ALL children aged 8-13 years who underwent maintenance phase chemotherapy. The sample was taken using consecutive sampling techniques with a total of 22 people. The data collection tool uses the Multidimensional Fatigue Scale questionnaire. The results showed that the average fatigue scale in the pre-test intervention group was 31.18 and post-test 47.64. The pre-test control group was 27.27 and post-test 39.18. The level of fatigue experienced by children decreased (p 0.000) after being given physical exercise walking 5 minutes, six times in 14 days. The involvement of health workers is expected in conducting a comprehensive assessment of fatigue symptoms, and the results of this study can be used as one of the physical exercise interventions in the management of fatigue in children with leukemia.