•Both direct and indirect energy-related CO2 emissions are considered.•The driving factors are analysed at both the national and provincial levels.•Economic output was the dominant positive driving ...factor.•While energy intensity was the dominant negative driving factor.•Driving factors in China show significant spatial characteristics.
To grasp the characteristics of CO2 emissions across provinces in China and to determine changes in the centre of gravity of CO2 emissions over the 2000–2014 period, a gravity model is first used to examine the spatial distribution and centre of gravity of energy-related CO2 emissions. Then, to explore the main factors driving CO2 emission changes and to uncover feasible ways to reduce CO2 emissions, this paper decomposes changes in energy-related CO2 emissions into a population effect (ΔCP), an economic output effect (ΔCQ), an industrial structure effect (ΔCS), an energy intensity effect (ΔCI), an energy structure effect (ΔCM) and a carbon dioxide emission coefficient effect (ΔCU) at both the national and provincial levels based on the Log-Mean Divisia Index (LMDI) method. The results indicate that (1) energy-related CO2 emissions rose by approximately 5.46 billion tonnes during the 2000–2014 period, with secondary industry accounting for approximately 80% of total CO2 emissions. (2) Economic output (Q) was the dominant positive driving factor, and energy intensity (I) was the dominant negative driving factor. The population changes had a weak positive effect on CO2 emissions, but the industrial structure effect and energy structure effect varied considerably over the years without showing clear trends. (3) Over multiple spatial scales, the contribution ratios of the factors varied significantly across provinces; in general, the positive driving effects outweighed the negative inhibiting effects. Based on these empirical findings, policy recommendations to further reduce CO2 emissions are provided. The Chinese central and local governments should make full use of the important inhibiting factors, i.e., energy intensity and energy structure, and strive for breakthroughs in secondary sector.
•Analytical optical field of a cosh-Airy beam in uniaxial crystals is derived.•The centre of gravity, the beam spot size, and the linear momentum are derived.•The influence of the uniaxial crystal on ...the cosh-Airy beam is investigated.•The effect of the cosh part on the cosh-Airy beam is also investigated.•The propagation properties of the cosh-Airy beam are shown to be abundant.
Analytical optical field of a cosh-Airy beam propagating in uniaxial crystals orthogonal to the optical axis is presented. Analytical expressions of the centre of gravity, the beam spot size, and the linear momentum for the cosh-Airy beam in uniaxial crystals are also derived, respectively. The propagation properties of a cosh-Airy beam are numerically demonstrated in the uniaxial crystal. The cosh-Airy beam still has the feature of self-acceleration in the two transverse directions. However, the cosh-Airy beam in the y-direction accelerates more slowly than that in the x-direction. The centre of gravity and the beam spot size in the y-direction are always less than those in the x-direction. The influence of the uniaxial crystal on the intensity distribution, the phase distribution, the centre of gravity, the beam spot size, and the linear momentum of a cosh-Airy beam is investigated. The effect of the cosh part on the centre of gravity, the beam spot size, and the linear momentum is also studied in detail. The centre of gravity of the cosh-Airy beam is less than that of the corresponding Airy beam. However, the beam spot size and the linear momentum of the cosh-Airy beam are larger than those of the corresponding Airy beam.
This paper presents an analysis of loaded freight wagon dynamics in curve alignments. We investigate the effects of the combined centre of gravity (CCOG) on the running safety of freight wagons and ...examine proper position of the CCOG. A simple wagon-rail model is implemented using the multibody dynamics software ADAMS/Rail. The simulation model is operated on curve tracks with various radii and velocities and the curving performances are evaluated. The results indicate that the CCOG can be located within a flexible and accurate range. The longitudinal offset is good for the curving performance and the permissible lateral offset should be assessed based on the curve radius and cant deficiency.
Summary
Changing climate is already impacting the spatial distribution of many taxa, including bees, plants, birds, butterflies and fishes. A common goal is to detect range shifts in response to ...climate change, including changes in the centre of the population's distribution (the centre of gravity, COG), population boundaries and area occupied. Conventional estimators, such as the abundance‐weighted average (AWA) estimator for COG, confound range shifts with changes in the spatial distribution of available survey data and may be biased when the distribution of survey data shifts over time. AWA also does not estimate the standard error of COG in individual years and cannot incorporate data from multiple survey designs.
To explicitly account for changes in the spatial distribution of survey effort, we propose an alternative species distribution function (SDF) estimator. The SDF approach involves calculating distribution metrics, including COG, population boundary and area occupied, directly from the predicted species distribution or density function. We illustrate the SDF approach using a spatiotemporal model that is available as an r package. Using simulated data, we confirm that the SDF substantially decreases bias in COG estimates relative to the AWA estimator. We then illustrate the method by analysing data from two data sets spanning 1977–2013 for 18 marine fishes along the U.S. West Coast.
In our case study, the SDF estimator shows significant northward shifts for six of 18 species (with southward shifts for only 2), where two species (darkblotched and greenstriped rockfishes) have both a northward shift and a decreased area occupied. Pelagic species (e.g. Pacific hake and spiny dogfish) have more variable distribution than bottom‐associated species. We also find substantial differences between AWA and SDF estimates of COG that are likely caused by shifts in sampling distribution (which affect the AWA but not the SDF estimator).
We caution that common estimators for range shift can yield inappropriate inference whenever sampling designs have shifted over time. We conclude by suggesting further improvements in model‐based approaches to analysing climate impacts, including methods addressing the impact of local and regional temperature changes on species distribution.
Non-grain production of cultivated land (NGPOCL), as a severe threat to food security, has attracted great attention in China and other countries of the world. Although some scholars have focused on ...the NGPOCL, few studies performed the analysis at the plot scale across the whole region. This study takes Guanzhong Region as the study area and carries out a comprehensive analysis of NGPOCL according to the framework of "phenomenon-cause-countermeasure". According to the land-use map, the range of cultivated land was delineated; based on the 16-day time resolution MODIS vegetation index data, the NGPOCL range was further extracted from the cultivated land by distinguishing the grain/non-grain crops according to their seasonal variation characteristics on the vegetation index. Some spatial statistical methods were used to analyze the spatial-temporal characteristics of NGPOCL in the study area from 2000 to 2018, and it was observed as follows. Firstly, the NGPOCL problem in Guanzhong Region was getting worse during the study period, and the NGPOCL severity and area increased by 10.79% and 31.30% respectively. Secondly, the NGPOCL process showed significant temporal and spatial heterogeneity. The gravity center for NGPOCL was gradually shifted from Chunhua County to Xi'an City in the southeast. Meanwhile, the spatial autocorrelation of NGPOCL was weakening, and Moran' I was declining year by year. These indicated that the NGPOCL had been fully rolled out in the Guanzhong Region, and it had evolved from the past adjacent expansion to the current full bloom. As for the driving mechanism, while those natural factors determined the skeleton of the NGPOCL pattern, social and economic factors played an important role in the evolution process following, and different industrial policies have dominated the NGPOCL expansion at different stages. In the future, it is necessary to pay attention to the impact of industrial policies on NGPOCL and consider the demands of urbanization for non-grain agricultural products properly, so as to develop the characteristic agricultural products industry in a reasonable and compliant manner.
•Range for non-grain production of cultivated land (NGPOCL) in region scale was mapped.•NGPOCL in Guanzhong Region was getting worse but with a slowed-down speed.•Spatiotemporal heterogeneity of NGPOCL was studied by GIS and Spatial Statistics.•NGPOCL was fully rolled out in the study area, and its driving mechanism also changed.
The combined centre of gravity (CCOG) height of a suspended monorail train may have a certain influence on the centrifugal forces acting on the train under crosswinds, and changes in centrifugal ...forces will further affect the dynamic interactions among the crosswind, the vehicle and the bridge subsystem. To investigate the effect of CCOG height on the dynamic behaviour of the train, this paper proposes an improved wind-vehicle-bridge coupling dynamics model considering the CCOG height for the suspended monorail system, in which the uneven passenger weight distribution is simulated with various vehicle parameters, and the aerodynamic wind forces acting on the running vehicles and bridge are simulated considering the effect of resultant wind yaw angle. The influences of passenger number, wind velocity, and vehicle speed on the dynamic behaviours of suspended monorail trains are also explored. The results indicate that the suspended monorail train has a certain self-balancing ability due to its unique structure type, which causes the lateral responses of the car body to attenuate with the increasing car weight. In addition, it is conservative to not consider the effect of CCOG height in the lateral ride comfort evaluation of the suspended monorail train subject to crosswinds.
Sacroiliac (SI) joint dysfunction accounts for altered postural stability which can cause a continuously intense pain level and range of disabilities.
To investigate the correlation of postural ...stability with pain, disability & QOL among sufferers of sacroiliac joint dysfunction.
This cross-sectional research was undertaken at Rehabilitation Centre, Jamia Hamdard University.
A total of fifty participants were recruited using sample of convenience according to inclusion and exclusion criteria. After obtaining informed consent, three pain provocative tests and one motion palpation test were used to determine sacroiliac joint dysfunction. Humac balance master system (CSMi USB powered, Stoughton, USA), Visual analogue scale (VAS), modified Oswestry Disability Index (ODI) & WHO QOL-BREF (US version) were used to assess postural stability, pain, disability & Quality of life (QOL) respectively. Data analysis was done for correlation by SPSS version 24.0.
Strong positive correlations were found between reaction time, VAS (r = 0.791) and modified ODI score (r = 0.576) and weak positive correlations between eyes closed solid surface (ECSS) component of modified clinical test of sensory interaction & balance with VAS (r = 0.333) and with modified ODI score (r = 0.304) and eyes open foam surface (EOFS) component with environmental component of QOL (r = 0.287). There were negative correlations between reaction time, physical health (r = −0.413), psychological health (r = −0.375), social relations (r = −0.305), and environment (r = −0.379) parameters of QOL.
According to the findings of the study, there were positive correlations of reaction time with pain and disability and negative correlations with QOL. Awareness of clinicians regarding the altered postural stability can help in improvising the assessment and treatment protocols for patients of SI dysfunction.
In vehicular accident reconstruction, a number of parameters need to be estimated, as commonly no specific measurement data or convenient measurement methods are available. One of these parameters is ...the position of a car’s centre of gravity. Depending on the impact configuration, the centre of gravity may have a significant influence on the reconstruction result. A number of regression models and rules of thumb have already been developed in the past to calculate the position of the centre of gravity. The further automotive vehicle development in recent years has led to different vehicle architectures with larger masses. This study therefore deals with developing and testing a new regression model for vehicles, distinguishing between conventional and electric drives. That is based on the analysis of 147 rollover stability measurements of road vehicles from the years 2016–2022. The model developed from these tests for the centre of gravity height shows a good fit with the measurement data and only requires knowledge of the roof height.
•Evaluation of latest rollover stability measurement data•Development of an regression model for approximation of CG height of CEVs•Development of an regression model for approximation of CG height of BEVs
Restoring the ability to walk with a prosthesis is considered a fundamental rehabilitation goal after transfemoral amputation. An essential prerequisite for achieving this goal is adequate force ...transmission between the prosthesis and the body. Does bone anchorage of an artificial limb permit a more normal force transmission?
Data of 15 healthy subjects, nine amputees fitted with bone-anchored prostheses, nine amputees using socket prostheses, and 18 patients with a total hip replacement were included in this multicenter, observational study. Ground reaction force was measured using Kistler force plates. Kinematics was recorded with 12 Vicon Bonita cameras. Subjects were instructed to walk at three different speeds: first at their self-selected, then at slow, and finally at fast speed.
Self-selected walking speeds of subject groups were significantly different, osseointegrated amputees walked the slowest. The lowest ground reaction force was measured for osseointegrated amputees on the prosthetic side, who also showed the highest force on their contralateral side. Patients with hip replacements showed values similar as healthy subjects. The vertical center of gravity movement was specific for each subject group.
The force transmission capacity of the bone-anchored prosthetic leg is limited during walking and is lower than both in socket prostheses users without symptoms and patients with total hip replacement. Therefore, active amputees well fitted with a socket prosthesis who consider a transition to bone-anchorage should be advised that their walking speed may decrease with high probability, and that their self-selected walking speed may even be slower than 3 km/h.
•Restoring gait with bone-anchored versus socket prostheses and hip replacements•Osseointegrated amputees have a special gait adaptation to unload the prosthetic leg•Physiological gait is impossible•Reduced force transmission in the implant-bone interface can be ruled out as a cause•Bone-anchored prostheses can be recommended at walking speeds of slower than 3 km/h
This article applies grounded theory and epistemological, teleological, ontological, and methodological (ETOM) lenses to describe the prevalent contemporary theories of the centre of gravity concept, ...originated by Carl von Clausewitz. These include the theories of John Warden, Joe Strange & Richard Iron, Antulio Echevarria II, Milan Vego, Dale Eikmeier, and Jacob Barfoed. The article then compares the theories across 14 deduced theoretical aspects and produces a comparison matrix, that can be used as an analytical tool, and discusses implications as guidance for further research and doctrine development. The article argues that the term "centre of gravity" is polluted, and that the application of the term in military planning and doctrines requires careful attention to the specific theory being applied, so that logical consistency and clear, accurate communication is achieved. Alternatively, the concept may be removed from doctrine altogether, renovated with inclusion of a new unpolluted term, or reconstructed with removal of the centre of gravity, leaving a "critical factor analysis" concept behind. This article also provides a level of granularity to the debate about the concept, that renders critics like Paparone & Davis Jr and Zweibelson partly irrelevant and can provide a more nuanced and qualitative basis for future discussion.
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Dostopno za:
BFBNIB, DOBA, IZUM, KILJ, NUK, ODKLJ, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
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