Securing offshore resources development:A mathematical investigation into gas leakage in long-distance flexible pipes

Gas flexible pipes are critical multi-layered equipment for offshore oil and gas development.Under high pressure conditions,small molecular components of natural gas dissolve into the polymer inner liner of the flexible pipes and further diffuse into the annular space,incurring annular pressure build-up and/or production of acidic environment,which poses serious challenges to the structure and integrity of the flexible pipes.Gas permeation in pipes is a complex phenomenon governed by various factors such as internal pressure and temperature,annular structure,external temperature.In a long-distance gas flexible pipe,moreover,gas permeation exhibits non-uniform features,and the gas permeated into the annular space flows along the metal gap.To assess the complex gas transport behavior in long-distance gas flexible pipes,a mathematical model is established in this paper considering the multiphase flow phenomena inside the flexible pipes,the diffusion of gas in the inner liner,and the gas seepage in the annular space under varying permeable properties of the annulus.In addition,the effect of a variable temperature is accounted.A numerical calculation method is accordingly constructed to solve the coupling mathematical equations.The annular permeability was shown to significantly influence the distribution of annular pressure.As permeability increases,the annular pressure tends to become more uniform,and the annular pressure at the wellhead rises more rapidly.After annular pressure relief followed by shut-in,the pressure increase follows a convex function.By simulating the pressure recovery pattern after pressure relief and comparing it with test results,we deduce that the annular permeability lies between 123 and 512 m D.The results help shed light upon assessing the annular pressure in long distance gas flexible pipes and thus ensure the security of gas transport in the emerging development of offshore resources.

Crop Resources Ethic in Plant Genetic Engineering and Fortune Transfer Between Generations

The relation between human and crop resources belongs to the ethic of resources exploitation. The purposes of discussing the ethic of crop resources are to protect the ecology and safety of crops, to gain sustainable development, furthermore, to choose and form the production structure that is favorable to saving crop resources and protecting the ecology of crops. Plant genetic engineering is the technology of molecule breeding of rearrangement of inheritance materials at the level of molecule directionally, of improving plant properties and of breeding high quality and yield varieties of crops. The prominent effects of the technology on the crop ecological system are human subjective factors increasing as well as violating the nature and intensifying the conflict between human being and nature. Therefore, in plant genetic engineering, crop resources exploitation should follow certain ethic principles. Under the theory of ethics of natural resources, by the means of biologinal-statistics, the author systematically analyzed the possible model of crop resources transfer between generations as well as the transfer mode of magnitude of real materials and magnitude of value.

Agricultural Machinery Input,Labor Resource Allocation,and Rural Household Land Transfers

This paper explores the impact of agricultural machinery input on rural households’land transfers,which is conducive to the acceleration of agricultural modernization,agricultural production at scale,and rural revitalization.By using the micro-data on rural households(2014–2018)from China Family Panel Studies(CFPS),we made an empirical analysis of the impact of agricultural machinery input on land transfers and drew three conclusions.First,agricultural machinery input has a positive impact on land transfers,which means the more rural households invest in agricultural machinery,the more willing they are to participate in land transfers.Second,the impact of agricultural machinery input on land transfers is mainly exerted by adjusting the allocation of labor resources for rural households,or rather by increasing the number of farmers engaged in agriculture and reducing the number of farmers-turned traders and workers to facilitate land transfers.Third,the impact of agricultural machinery input on land transfers concerns both the positive transfers-in and the negative transfers-out,and such an impact stays stable across income groups.Accordingly,we should further increase agricultural machinery-related subsidies,improve the agricultural machinery service outsourcing market,and help rural households to reasonably allocate their labor resource endowments and invest in agricultural machinery to increase land transfers.

Human Carrying Capacity of Rangeland Resources in China′s Mountain Areas

Based on analysis of the development potential of rangeland resources in China＇s mountain areas, the paper makes analysis and forecast in human carrying capacity of rangeland resources. It provides some reference for drawing up the development strategy in mountain areas.

A wave energy resource assessment in the China's seas based on multi-satellite merged radar altimeter data

Wave energy resources are abundant in both offshore and nearshore areas of the China＇s seas. A reliable assessment of the wave energy resources must be performed before they can be exploited. First, for a water depth in offshore waters of China, a parameterized wave power density model that considers the effects of the water depth is introduced to improve the calculating accuracy of the wave power density. Second, wave heights and wind speeds on the surface of the China＇s seas are retrieved from an AVISO multi-satellite altim-eter data set for the period from 2009 to 2013. Three mean wave period inversion models are developed and used to calculate the wave energy period. Third, a practical application value for developing the wave energy is analyzed based on buoy data. Finally, the wave power density is then calculated using the wave field data. Using the distribution of wave power density, the energy level frequency, the time variability indexes, the to-tal wave energy and the distribution of total wave energy density according to a wave state, the offshore wave energy in the China＇s seas is assessed. The results show that the areas of abundant and stable wave energy are primarily located in the north-central part of the South China Sea, the Luzon Strait, southeast of Taiwan in the China＇s seas; the wave power density values in these areas are approximately 14.0–18.5 kW/m. The wave energy in the China’s seas presents obvious seasonal variations and optimal seasons for a wave energy utilization are in winter and autumn. Except for very coastal waters, in other sea areas in the China＇s seas, the energy is primarily from the wave state with 0.5 m≤Hs≤4 m, 4 s≤Te≤10 s whereHs is a significant wave height andTe is an energy period; within this wave state, the wave energy accounts for 80% above of the total wave energy. This characteristic is advantageous to designing wave energy convertors （WECs）. The practical application value of the wave energy is higher which can be as an effective supplement for an energy con-sumption in some areas. The above results are consistent with the wave model which indicates fully that this new microwave remote sensing method altimeter is effective and feasible for the wave energy assessment.

Joint Scheduling and Resource Allocation for Federated Learning in SWIPT-Enabled Micro UAV Swarm Networks

Micro-UAV swarms usually generate massive data when performing tasks. These data can be harnessed with various machine learning(ML) algorithms to improve the swarm’s intelligence. To achieve this goal while protecting swarm data privacy, federated learning(FL) has been proposed as a promising enabling technology. During the model training process of FL, the UAV may face an energy scarcity issue due to the limited battery capacity. Fortunately, this issue is potential to be tackled via simultaneous wireless information and power transfer(SWIPT). However, the integration of SWIPT and FL brings new challenges to the system design that have yet to be addressed, which motivates our work. Specifically,in this paper, we consider a micro-UAV swarm network consisting of one base station(BS) and multiple UAVs, where the BS uses FL to train an ML model over the data collected by the swarm. During training, the BS broadcasts the model and energy simultaneously to the UAVs via SWIPT, and each UAV relies on its harvested and battery-stored energy to train the received model and then upload it to the BS for model aggregation. To improve the learning performance, we formulate a problem of maximizing the percentage of scheduled UAVs by jointly optimizing UAV scheduling and wireless resource allocation. The problem is a challenging mixed integer nonlinear programming problem and is NP-hard in general. By exploiting its special structure property, we develop two algorithms to achieve the optimal and suboptimal solutions, respectively. Numerical results show that the suboptimal algorithm achieves a near-optimal performance under various network setups, and significantly outperforms the existing representative baselines. considered.

Quality of life, work productivity impairment and healthcare resources in inflammatory bowel diseases in Brazil

BACKGROUND Inflammatory bowel diseases(IBD)have been associated with a low quality of life(QoL)and a negative impact on work productivity compared to the general population.Information about disease control,patient-reported outcomes(PROs),treatment patterns and use of healthcare resources is relevant to optimizing IBD management.AIM To describe QoL and work productivity and activity impairment(WPAI),treatment patterns and use of healthcare resources among IBD patients in Brazil.METHODS A multicenter cross-sectional study included adult outpatients who were previously diagnosed with moderate to severe Crohn’s disease(CD)or ulcerative colitis(UC).At enrolment,active CD and UC were defined as having a Harvey Bradshaw Index≥8 or a CD Activity Index≥220 or calprotectin>200μg/g or previous colonoscopy results suggestive of inadequate control(per investigator criteria)and a 9-point partial Mayo score≥5,respectively.The PRO assessment included the QoL questionnaires SF-36 and EQ-5D-5L,the Inflammatory Bowel Disease Questionnaire(IBDQ),and the WPAI questionnaire.Information about healthcare resources and treatment during the previous 3 years was collected from medical records.Chi-square,Fisher’s exact and Student’s t-/Mann-Whitney U tests were used to compare PROs,treatment patterns and the use of healthcare resources by disease activity(α=0.05).RESULTS Of the 407 patients in this study(CD/UC:64.9%/35.1%,mean age 42.9/45.9 years,54.2%/56.6%female,38.3%/37.1%employed),44.7%/25.2%presented moderate-to-severe CD/UC activity,respectively,at baseline.Expressed in median values for CD/UC,respectively,the SF-36 physical component was 46.6/44.7 and the mental component was 45.2/44.2,the EQ-visual analog scale score was 80.0/70.0,and the IBDQ overall score was 164.0/165.0.Moderate to severe activity,female gender,being unemployed,a lower educational level and lower income were associated with lower QoL(P<0.05).Median work productivity impairment was 20%and 5%for CD and UC patients,respectively,and activity impairment was 30%,the latter being higher among patients with moderate to severe disease activity compared to patients with mild or no disease activity(75.0%vs 10.0%,P<0.001).For CD/UC patients,respectively,25.4%/2.8%had at least one surgery,38.3%/19.6%were hospitalized,and 70.7%/77.6%changed IBD treatment at least once during the last 3 years.The most common treatments at baseline were biologics(75.3%)and immunosuppressants(70.9%)for CD patients and 5-ASA compounds(77.5%)for UC patients.CONCLUSION Moderate to severe IBD activity,especially among CD patients,is associated with a substantial impact on QoL,work productivity impairment and an increased number of IBD surgeries and hospitalizations in Brazil.

RELATIVE SEA LEVEL RISE AND ITS EFFECTS ON ENVIRONMENT AND RESOURCES IN CHINAS COASTAL AREAS

Due to global climate warming and natural and man-made land subsidence etc., relative sea level rise in the coastal plains of China will exceed 2-3 times over the golbal mean value during the first half part of the 21st century. It will result in a series of adverse impacts on evolution of natural environment and socioeconomic development of the coastal area. This paper analyses environmental and resource effects induced by relative sea level rise in China's coastal areas on the basis of rough estimate of future relative sea level rise. These effects include inundating tidal flat and wetlands and increase in inundated risk of coastal habitable land,exacerbating storm surge. coastal erosion, flooding and salt water intrusion hazards.as well as endangering land. water. tourism and living resources and their utilization.

HAS Dynamic Buffer-Driven Resource Management to Enhance QoE in Mobile Network

Hypertext transfer protocol(HTTP) adaptive streaming(HAS) plays a key role in mobile video transmission. Considering the multi-segment and multi-rate features of HAS, this paper proposes a buffer-driven resource management(BDRM) method to enhance HAS quality of experience(QoE) in mobile network. Different from the traditional methods only focusing on base station side without considering the buffer, the proposed method takes both station and client sides into account and end user's buffer plays as the drive of whole schedule process. The proposed HAS QoE influencing factors are composed of initial delay, rebuffering and quality level. The BDRM method decomposes the HAS QoE maximization problem into client and base station sides separately to solve it in multicell and multi-user video playing scene in mobile network. In client side, the decision is made based on buffer probe and rate request algorithm by each user separately. It guarantees the less rebuffering events and decides which HAS segment rate to fetch. While, in the base station side, the schedule of wireless resource is made to maximize the quality level of all access clients and decides the final rate pulled from HAS server. The drive of buffer and twice rate request schemes make BDRMtake full advantage of HAS's multi-segment and multi-rate features. As to the simulation results, compared with proportional fair(PF), Max C/I and traditional HAS schedule(THS) methods, the proposed BDRM method decreases rebuffering percent to 1.96% from 11.1% with PF and from 7.01% with THS and increases the mean MOS of all users to 3.94 from 3.42 with PF method and from 2.15 with Max C/I method. It also guarantees a high fairness with 0.98 from the view of objective and subjective assessment metrics.

China＇s Graphite Resources and the Supply-Demand Situation

Graphite is a rare and important nonmetallic mineral. Till 2017, the global graphite resource reserves had exceeded one billion tons, which are mainly distributed in China （0.45 billion tons）, Mozambique （0.14 billion tons）, Madagascar （0.1 billion tons）, Turkey （0.09 billion tons）, Brazil （0.07 billion tons）, and Tanzania （0.07 billion tons）. These six countries include about 92% of the global graphite resource reserves, of which China accounts for about 45% of the world＇s total resource reserves.

Study on human resources cost accounting based on standards and general rules

The issue of the new standards for employees＇ salary and general financial rules that include employees＇ salary and relevant expenditures, have a great impact on human resources cost accounting. This paper performs a specialized study on human resources cost and employees＇ salary, accounts setting and accounting treatment for human resources cost accounting, human resources cost report, etc. on the basis of relevant provisions in the new Chinese accounting standards, the general financial rules, international accounting standards, and relevant academic research findings.

Fluctuating resources,disturbance and plant strategies:diverse mechanisms underlying plant invasions

This paper examines the hypothesis that non-native plant invasions are related to fluctuating resource availability as proposed by Davis et al. （2000）. I measured relative functional responses of both invasive and native plants to changed resource availability due to nutrient enrichment and rainfall, and to increased disturbance. Data are presented from studies in two contrasting ecosystems. First is a series of glasshouse and field experiments on the invader Hieracium lepidulum and associated invasive and native species in subalpine temperate New Zealand. Second is a field study of invasive and native plant responses to altered disturbance regimes and rainfall from tropical savannas of north eastern Australia. Invaders responded differently from native species to changes in resource availability in both subalpine and tropical studies. However, invaders differed among themselves showing that different species exploit different functional niches to invade their respective habitats. These findings contribute to the contention that the fluctuating resource hypothesis does not provide a universal explanation for plant invasions. The diverse functional responses to increased resource availability among invaders in this and previous studies suggest that the cause of invasion depends on unique combinations of habitat and functional attributes of invaders and native assemblages. Such findings imply that universal predictions of what will happen under climate change scenarios across the globe will be difficult to make.

Management Model of Resources Equilibrium Distribution among Overlapping-Generations

The overlapping generation models the western scholars have designed from various perspectives to address different kinds of issues do not reflect Chinese emerging political and economic problems, and cannot be entirely and blindly applied to Chinese practical situation. In this paper the authors endeavor to incorporate some western scholars' research results into their own research findings to present overlapping generations model theory in a new perspective through establishing an overlapping generations theory on population including articulation of concepts and theorems of biological generation, economic generation and social generation and the overlapping periods in biological generation and two overlapping periods in economic generation among three generations. This management model with equilibrium distribution of resource wealth includes overlapping generations length model (6), equilibrium transfer model (θ) and a complete model on equilibrium distribution among generations (δ-θ). The model

An Analysis of Labor Resources “One River and Two Tributaries” Region in Tibet, China

Focusing on the region of Yarlung Zangbo River and the middle reaches of itstwo tributaries of Nianchu River and Lhasa River in Tibet (Hereafter referred to as the 'One Riverand Two Tributaries' region), and based on the data from China 3rd, 4th and5th population censuses,the article has analyzed change patterns of this region' s labor force. Major findings from thestudy are summarized as follows; (1) Compared with the data from the 3rd census, labor forcepopulation in 2000 has increased significantly. (2) Children dependency coefficient has dropped,while old people dependency coefficient has changed very slightly with an increase of 0. 047% only.(3) Compared 2000 with 1982, illiteracy and semi-illiteracy rate of the population above 15 yearsold have decreased significantly by 30. 69 percentage points, but still higher than the nationalaverage. (4) Women' s illiteracy rate has dropped faster than men's, but up to 2000 it was generallyquite high. The upgrading of the entire population's overall quality has a long way to go.

Climate Change and its Impact on Water Resources in the Huai River Basin

Rainfall and air temperature data from six meteorological stations above the Bengbu Sluice and hydrological and water resources evaluation data from the Bengbu Hydrological Station in the Huai River Basin from 1961 to 2008 are used to analyze the impact of changes in climatic factors on the amount of water resources in the Basin. There was a general trend of rise in its average annual air temperature, with the highest increase of 0.289℃/10a recorded at Bengbu in Anhui Province. Rising rainfall was mainly observed in the western part of the study area, while rainfall actually declined in the eastern part, i.e. the middle reaches of the Huai River. The Average rainfall in the study area was in a vaguely declining trend. In other words, the rainfall in the Basin is still much affected by natural fluctuations. On the whole, there was a trend of gradual decrease in the quantity of the Basin＇s water resources for the period under study. Water resources quantity is found to fall with decreasing rainfall and rising air temperature. Regression analysis is used to establish a mathematical model between water resources quantity and climatic factors （i.e. air temperature and rainfall） in order to explore the impact of climate change on water resources in the Basin. Moreover, various scenarios are set to quantitatively analyze the response of water resources to climate change. Sensitivity analysis shows that changes in rainfall have a much bigger impact on its water resources quantity than changes in its air temperature.

Adaptive Time Slot Resource Allocation in SWIPT IoT Networks

The rapid advancement of Internet of Things(IoT)technology has brought convenience to people’s lives;however further development of IoT faces serious challenges,such as limited energy and shortage of network spectrum resources.To address the above challenges,this study proposes a simultaneous wireless information and power transfer IoT adaptive time slot resource allocation(SIATS)algorithm.First,an adaptive time slot consisting of periods for sensing,information transmission,and energy harvesting is designed to ensure that the minimum energy harvesting requirement ismet while the maximumuplink and downlink throughputs are obtained.Second,the optimal transmit power and channel assignment of the system are obtained using the Lagrangian dual and gradient descent methods,and the optimal time slot assignment is determined for each IoT device such that the sum of the throughput of all devices is maximized.Simulation results show that the SIATS algorithm performs satisfactorily and provides an increase in the throughput by up to 14.4%compared with that of the fixed time slot allocation(FTS)algorithm.In the case of a large noise variance,the SIATS algorithm has good noise immunity,and the total throughput of the IoT devices obtained using the SIATS algorithm can be improved by up to 34.7%compared with that obtained using the FTS algorithm.

Prospering Revolution of Resource Efficiency in Northeast Industrial Area in China

Despite its strong advantages in resource, technology and human resource, China's Northeast Industrial Area is also experiencing problems of unreasonable industrial structure, envi- ronmental pollution, and the degradation of ecological condition, etc., which prevent this area from achieving a sustainable devel- opment. Through analyzing the resource problem, the present paper proposed a strategy of circular economy for the prosperity of this are, discussed the theories of circular economy and re- source recycling, and finally concluded that improving resource productivity is at the core of circular economy.

The Study of Woodland Use Efficiency from the Perspective of Forest Resources Change

From the perspective of forest resources change,this article uses comparative analysis and panel data regression to study the woodland use efficiency from forest resources quantity and quality change.The results show that although the forest coverage and forest stock volume per hectare show an overall upward trend,there are different change laws between the two;there are also differences in the influencing factors between forest coverage and forest stock volume per hectare( population density,rainfall and project having significant effect on forest coverage;population density,economic density and institution having significant effect on forest stock per hectare).Finally the recommendations are put forth for improving the woodland resources use efficiency:it is necessary to improve both the forest quantity and forest quality,focus on demand and supply,and pay equal attention to project promotion and property rights system reform.