Analysis on unit maximum capacity of orthogonal multiple watermarking for multimedia signals in B5G wireless communications

Beyond-5G(B5G)aims to meet the growing demands of mobile traffic and expand the communication space.Considering that intelligent applications to B5G wireless communications will involve security issues regarding user data and operational data,this paper analyzes the maximum capacity of the multi-watermarking method for multimedia signal hiding as a means of alleviating the information security problem of B5G.The multiwatermarking process employs spread transform dither modulation.During the watermarking procedure,Gram-Schmidt orthogonalization is used to obtain the multiple spreading vectors.Consequently,multiple watermarks can be simultaneously embedded into the same position of a multimedia signal.Moreover,the multiple watermarks can be extracted without affecting one another during the extraction process.We analyze the effect of the size of the spreading vector on the unit maximum capacity,and consequently derive the theoretical relationship between the size of the spreading vector and the unit maximum capacity.A number of experiments are conducted to determine the optimal parameter values for maximum robustness on the premise of high capacity and good imperceptibility.

Fixed Ammonium Content and Maximum Capacity of Ammonium Fixation in Major Types of Tillage Soils in Hunan Province,China

In order to understand the status of fixed ammonium, fixed ammonium content, maximum capacity of ammonium fixation, and their influencing factors in major types of tillage soils of Hunan Province, China, were studied with sampling on fields, and laboratory incubation and determination. The main results are summarized as follows： （1） Content of fixed ammonium in the tested soils varies greatly with soil use pattern and the nature of parent material. For the paddy soils, it ranges from 135.4 ± 57.4 to 412.8±32,4 mg kg^-1, with 304.7±96.7 mg kg^-1 in average; while it ranges from 59.4 to 435.7 mg kg^-1, with 230.1 ± 89.2 mg kg^-1 in average for the upland soils. The soils developed from limnic material and slate had higher fixed ammonium content than the soils developed from granite. The percentage of fixed ammonium to total N in the upland soils is always higher than that in the paddy soils. It ranges from 6.1 ±3.6% to 16.6±4.6%, with 14.0% ±5.1% in average for the paddy soils and it amounted to 5.8±2.0% to 40.1 ± 17.8%, with 23.5 ± 14.2% in average for upland soils. （2） The maximum capacity of ammonium fixation has the same trend with the fixed ammonium content in the tested soils. For all the tested soils, the percentage of recently fixed ammonium to maximum capacity of ammonium fixation is always bellow 20% and it may be due to the fact that the soils have high fertility and high saturation of ammonium-fixing site. （3） The clay content and clay composition in the tested soils are the two important factors influencing their fixed ammonium content and maximum capacity of ammonium fixation. The results showed that hydrous mica is the main 2：1 type clay mineral in 〈 0.02 mm clay of the paddy soils, and its content in 0.02-0.002 mm clay is much higher than that in 〈 0.002 mm clay of the soils. The statistical analysis showed that both the fixed ammonium content and the maximum capacity of ammonium fixation of the paddy soils were positively correlated with the total 2：1 type clay mineral content and hydrous mica content in 〈 0.02 mm clay and 0,02-0.002 mm clay at the significant level of P0.01 or P0.05, respectively, but not correlated with the total 2：1 type clay mineral content and hydrous mica content in 〈0.002 mm clay significantly, It demonstrated that the ammonium-fixing matrix of the tested soils mainly exists in the 0.02-0.002 mm clay. The above-mentioned results showed that fixed ammonium is a major form of N in the tillage soils in Hunan Province, China. It would play an important role in N nutrition of crops, especially for upland crops, and deserve to be further researched.

AN INVERSE MAXIMUM CAPACITY PATH PROBLEM WITH LOWER BOUND CONSTRAINTS

The computational complexity of inverse mimimum capacity path problem with lower bound on capacity of maximum capacity path is examined, and it is proved that solution of this problem is NP-complete. A strong polynomial algorithm for a local optimal solution is provided.

Flexible path planning-based reconfiguration strategy for maximum capacity utilization of battery pack

Maximizing the utilization of lithium-ion battery capacity is an important means to alleviate the range anxiety of electric vehicles.Battery pack inconsistency is the main limiting factor for improving battery pack capacity utilization,and poses major safety hazards to energy storage systems.To solve this problem,a maximum capacity utilization scheme based on a path planning algorithm is proposed.Specifically,the reconfigurable topology proposed is highly flexible and fault-tolerant,enabling battery pack consistency through alternating cell discharge and reducing the increased risk of short circuits due to relay error.The Dijkstra algorithm is used to find the optimal energy path,which can effectively remove faulty cells and find the current path with the best consistency of the battery pack and the lowest relay loss.Finally,the effectiveness of the scheme is verified by hardware-in-the-loop experiments,and the experimental results show that the state-of-charge SOC consistency of the battery pack at the end of discharge is increased by 34.18%,the relay energy loss is reduced by 0.16%,and the fault unit is effectively isolated.

Increasing the Maximum Capacity Path in a Network and Its Application for Improving the Connection Between Two Routers

Abstract:This paper addresses the problem of improving the optimal value of the Maximum Capacity Path(MCP)through expansion in a flexible network,and minimizing the involved costs.The only condition applied to the cost functions is to be non-decreasing monotone.This is a non-restrictive condition,reflecting the reality in practice,and is considered for the first time in the literature.Moreover,the total cost of expansion is a combination of max-type cost(e.g.,for supervision)and sum-type cost(e.g.for building infrastructures,price of materials,price of labor,etc.).For this purpose,two types of strategies are combined:(l)increasing the capacity of the existing arcs,and(l)adding potential new arcs.Two different problems are introduced and solved.Both the problems have immediate applications in Internet routing infrastructure.The first one is to extend the network,so that the capacity of an McP in the modified network becomes equal to a prescribed value,therefore the cost of modifications is minimized.A strongly polynomial-time algorithm is deduced to solve this problem.The second problem is a network expansion under a budget constraint,so that the capacity of an McP is maximized.A weakly polynomial-time algorithm is presented to deal with it.In the special case when all the costs are linear,a Meggido's parametric search technique is used to develop an algorithm for solving the problem in strongly polynomial time.This new approach has a time complexity of O(n^(4)),which is better than the time complexity of O(n4 log(n)of the previously known method from literature.

A MODEL FOR THE“MAXIMUM CAPACITY” OF ROOMS OR OF SPACE

A discrete optimum mathematical model to derive the 'maximum capacity' of people in a room or in a space used for public gatherings is developed. There are two outcomes in the model. One is focused on whether the person farthest from exits can escape from the room. The other concentrates on the evacuation time of all the people in the room. According to the results of the two outcomes, a more reasonable 'maximum capacity' can be worked out in a simple way.

STUDY ON MAXIMUM HYDROGEN CAPACITY FOR Zr-Ni AMORPHOUS ALLOY

To design the amorphous hydrogen storage alloy efficiently, the maximum hydrogen capacities for Zr - Ni amorphous alloy were calculated. Based on the Rhomb Unit Structure Model(RUSM) for amorphous alloy and the experimental result that hydrogen atoms exist in 3Zr1Ni and 4Zr tetrahedron interstices in Zr-Ni amolphous alloy, the numbers of 3Zr-1Ni and 4Zr tetrahedron interstices in a RUSM were calculated which correspond to the hydrogen capacity. The two extremum Zr distribution states were calculated, such as highly heterogeneous Zr distribution and homogeneous Zr distribution. The calculated curves of hydrogen capacity with different Zr contents at two states indicate that the hydrogen capacity increases with increasing Zr content and reaches its maximum when Zr is 75%. The theoretical maximum hydrogen capacity for Zr - Ni amorphous alloy is 2.0 (H/M). Meanwhile, the hydrogen capacity of heterogenous Zr distribution alloy is higher than that of homogenous one at the same Zr content. The experimental results prove the calculated results reasonable, and accordingly, the experimental results that the distribution of Zr atom in amorphous alloy occur heterogeneous after a few hydrogen absorption desorption cycles can be explained.

The Clinical Role of Changes of Maximum Expiratory Flow at 25%and 50%of Vital Capacity before and after Bronchodilator Reversibility Test in Diagnosing Asthma

Summary:Changes of maximum expiratory flow at 25%and 50%of vital capacity(MEF2s and MEFso,respectively),and predominant parameters indicating small airways function in asthmatics before and after bronchodilator(BD)reversibility test have been less interpreted.Our study aimed to investigate the clinical role of changes of MEF2s and MEFso before and after BD reversibility test in diagnosing asthma.Forced expiratory volume in the first second(FEV),MEF2s,and MEFso were measured before and after BD reversibility test in 207 asthmatic patients using standard process.Forty healthy individuals were enrolled as controls.Receiver operating characteristic(ROC)curve was used to assess the diagnostic accuracy of reversibility of MEF2s and MEFgo before and after BD reversibility test(OMEF 2s%and AMEF so%,respectively)in diagnosing asthma.Among these functional criteria,AMEF2;%and 0MEFs%≥25%performed the best diagnostic performance.The sensitivity,specificity,and accuracy of AMEF 25%≥25%as an objcctive diagnostic test for asthma were 63.29%,87.50%,and 67.21%,and of AMEFs0%≥25%were 79.23%,85.00%,and 80.16%,respectively.The area under the ROC curve of the indicators was 0.8203 and 0.9104,respectively.By contrast,an increase in FEV≥12%and 200 mL demonstrated a sensitivity of 62.32%,specificity of 82.50%,and accuracy of 65.59%in diagnosing asthma.The changes of MEF2s and MEFso before and after BD reversibility test may be of additional value in the clinical diagnosis of asthma,with cutoff values of 25%being the most.

ON THE BOTTLENECK CAPACITY EXPANSION PROBLEMS ON NETWORKS

This article considers a class of bottleneck capacity expansion problems. Such problems aim to enhance bottleneck capacity to a certain level with minimum cost. Given a network G（V,A,C^-） consisting of a set of nodes V = {v1,v2,... ,vn}, a set of arcs A C {（vi,vj） ｜ i = 1,2,...,n; j = 1,2,...,n} and a capacity vector C. The component C^-ij of C is the capacity of arc （vi, vj）. Define the capacity of a subset A′ of A as the minimum capacity of the arcs in A, the capacity of a family F of subsets of A is the maximum capacity of its members. There are two types of expanding models. In the arc-expanding model, the unit cost to increase the capacity of arc （vi, vj） is ωij. In the node-expanding model, it is assumed that the capacities of all arcs （vi, vj） which start at the same node vi should be increased by the same amount and that the unit cost to make such expansion is wi. This article considers three kinds of bottleneck capacity expansion problems （path, spanning arborescence and maximum flow） in both expanding models. For each kind of expansion problems, this article discusses the characteristics of the problems and presents several results on the complexity of the problems.

Power optimization for maximum channel capacity in MIMO relay system

Introducing multiple-input multiple-output（MIMO） relay channel could offer significant capacity gain. And it is of great importance to develop effective power allocation strategies to achieve power efficiency and improve channel capacity in amplify-and-forward relay system. This article investigates a two-hop MIMO relay system with multiple antennas in relay node （RN） and receiver （RX）. Maximizing capacity with antenna selection（MCAS） and maximizing capacity with eigen-decomposition （MCED） schemes are proposed to efficiently allocate power among antennas in RN under first and second hop limited scenarios. The analysis and simulation results show that both MCED and MCAS can improve the channel capacity compared with uniform power allocation （UPA） scheme in most of the studied areas. The MCAS bears comparison with MCED with an acceptable capacity loss, but lowers the complexity by saving channel state information （CSI） feedback to the transmitter （TX）. Moreover, when the RN is close to RX, the performance of UPA is also close to the upper bound as the performance of first hop is limited.

“Extreme utilization” theory and practice in gas storages with complex geological conditions

Based on more than 20-year operation of gas storages with complex geological conditions and a series of research findings, the pressure-bearing dynamics mechanism of geological body is revealed. With the discovery of gas-water flowing law of multi-cycle relative permeability hysteresis and differential utilization in zones, the extreme utilization theory targeting at the maximum amount of stored gas, maximum injection-production capacity and maximum efficiency in space utilization is proposed to support the three-in-one evaluation method of the maximum pressure-bearing capacity of geological body, maximum well production capacity and maximum peak shaving capacity of storage space. This study realizes the full potential of gas storage(storage capacity) at maximum pressure, maximum formation-wellbore coordinate production, optimum well spacing density match with finite-time unsteady flow, and peaking shaving capacity at minimum pressure, achieving perfect balance between security and capacity. Operation in gas storages, such as Hutubi in Xinjiang, Xiangguosi in Xinan, and Shuang6 in Liaohe, proves that extreme utilization theory has promoted high quality development of gas storages in China.

Novel Radiation-Adjustable Heating Terminal Based on Flat Heat Pipe Combined with Air Source Heat Pump

The electrification of building heating is an effective way to meet the global carbon target. As a clean and sustainable electrified heating technology, air-source heat pumps (ASHPs) are widely used in areas lacking central heating. However, as a major component of space heating, heating terminals might not fit well with ASHP in order to achieve both intermittency and comfort. Therefore, this study proposes a novel radiation-adjustable heating terminal combined with an ASHP to achieve electrification, intermittency, and better thermal comfort. Radiant terminals currently suffer from three major problems: limited maximum heating capacity, inability to freely adapt, and difficulty with combining them with ASHPs. These problems were solved by improving the structural design of the novel terminal (Improvement A–E). Results showed that the maximum heating capacity increased by 23.6% and radiation heat transfer ratio from 10.1% to 30.9% was provided for users with the novel terminal. Further, new flat heat pipe (FHP) design improved stability (compressor oil return), intermittency (refrigerant thermal inertia), and safety (refrigerant leakage risk) by reducing the length of exposed refrigerant pipes. Furthermore, a new phased operation strategy was proposed for the novel terminal, and the adjustability of the terminal was improved. The results can be used as reference information for decarbonizing buildings by electrifying heating terminals.

Adsorption Properties and Cost of Dicarboxylic Nanocellulose on Copper Ions for Wastewater Treatment

The accumulation of Cu^(2+)in water is a potential threat to human health and environment.Dicarboxylic nano-cellulose(DNC)with rich carboxyl groups was prepared through the NaIO_(4)–NaClO_(2) sequential oxidation meth-od to efficiently remove copper ions,and the Cu 2+adsorption properties and cost were studied.The maximum adsorption capacity reached 184.2 mg/g at pH 6 and an adsorbent dose of 5 g/L.Theoretically,the maximum adsorption capacities of monocarboxylic nanocellulose(MNC),DNC,and tricarboxylic nanocellulose(TNC)with carboxyl groups as the main adsorption sites were calculated to be 228.7,261.3,and 148.1 mg/g,respectively.The Cu^(2+)adsorption costs of MNC,DNC,and TNC were calculated and compared with those of powdered activated carbon(PAC).The Cu^(2+)adsorption capacity of DNC is higher than that of PAC,and the adsorption cost is close to or lower than that of PAC,demonstrating that the DNC prepared by sequential oxidation of NaIO_(4)–NaClO_(2) has competitive adsorption capacity and cost in the treatment of wastewater containing Cu^(2+).

A comparison of flight energetics and kinematics of migratory Brambling and residential Eurasian Tree Sparrow

Background:Unlike resident birds,migratory birds are generally believed to have evolved to enhance flight efficiency;however,direct evidence is still scarce due to the difficulty of measuring the flight speed and mechanical power.Methods:We studied the differences in morphology,flight kinematics,and energy cost between two passerines with comparable size,a migrant(Fringilla montifringilla,Brambling,BRAM),and a resident(Passer montanus,Eurasian Tree Sparrow,TRSP).Results:The BRAM had longer wings,higher aspect ratio,lower wingbeat frequency,and stroke amplitude compared to the TRSP despite the two species had a comparable body mass.The BRAM had a significantly lower maximum speed,lower power at any specific speed,and thus lower flight energy cost in relative to the TRSP although the two species had a comparable maximum vertical speed and acceleration.Conclusions:Our results suggest that adaptation for migration may have led to reduced power output and maximum speed to increase energy efficiency for migratory flight while residents increase flight speed and speed range adapting to diverse habitats.

Key factors determining biochar sorption capacity for metal contaminants:a literature synthesis

The sorption capacity and affinity of biochar for metals are both important attributes that determine biochar’s suitability as a soil amendment for contaminant mitigation,yet few analyses have considered both characteristics simultaneously.We present a systematic review of literature published between 2010 and 2018 to test the hypothesis that sorption capacity and affinity are affected by biochar properties,attributes of the metal contaminant,and experimental conditions,in that order.We used random forest(RF)and multi-objective optimization to analyze data of 559 individual Langmuir adsorption isotherms extracted from 133 studies covering the sorption capacity(C_(max))and affinity(K_(L))of biochar for 17 different metals,elabo-rated from six different feedstock classes,three different types of feedstock pretreatment,and five types of post-pyrolysis treatment.Highest sorption values were obtained for Pb(II),Cr(IV),and Cd(II).The feedstock used was the key determinant influencing biochar’s capacity and affinity to sorb metal contaminants(first and fourth most important variable in RF mod-els for C_(max) and K_(L),respectively)with best results obtained for biochar elaborated from nutrient-dense feedstocks(animal biowaste,sludge,and manure).Biochars that had both high sorption capacity and affinity were the result of a longer dura-tion of pyrolysis;they had lower C and higher N and O content,as well as lower C/N and higher O/C and H/C ratios,higher pore volumes and higher pH.Applying some form of pretreatment was better than none,whereas chemical modification was the best of the post-treatment methods analyzed.This review demonstrates clearly that multiple parameters during the preparation process influence the effectiveness of biochar to immobilize metal contaminants.Future research that focuses on mechanisms and the underlying factors for the correlations observed should allow the development of biochar formulations that are even more effective at immobilizing metal contaminants in soils and sediments.