Experimental Study of Current Loss of Stainless Steel Magnetically Insulated Transmission Line with Current Density at MA/cm Level

A magnetically insulated transmission line （MITL） is used to transmit high power electric pulses in large pulse power systems. However, current loss is unavoidable, especially when the current density is up to 1 MA/cm. In the paper, the current loss of an MITL made of stainless steel, which is usually used in large pulse power generators, is experimentally studied, and possible mechanisms to explain the current loss of the MITL are analyzed and discussed. From the experimental results, the relationship between loss current density and input current density follows approximately a power law. The loss is also related to the configuration of the MITL.

Screw placement is everything: Risk factors for loss of reduction with volar locking distal radius plates

AIM To determine factors correlated with postoperative radial shortening in patients with distal radius fractures treated with volar locking distal radius plates.METHODS A total of 250 patients with a distal radius fracture stabilised with volar locking plates between January 2010 and December 2014 were included in a multicentre retrospective cohort study. We measured the distance of the distal locking screws to the joint line immediately postoperatively and then measured radial shortening after six to eight weeks using the change in ulnar variance.RESULTS Multivariate linear regression analysis showed that there was a significant linear association between the distance of the screws from the joint line and radial shortening. No other patient, injury, or treatment-related characteristic significantly influenced radial shortening in multivariate analysis.CONCLUSION Distal locking screws should be placed as close as possible to the subchondral joint line to prevent postoperative loss of reduction.

Fuzzy-GA based algorithm for optimal placement and sizing of distribution static compensator (DSTATCOM) for loss reduction of distribution network considering reconfiguration

This work presents a fuzzy based methodology for distribution system feeder reconfiguration considering DSTATCOM with an objective of minimizing real power loss and operating cost. Installation costs of DSTATCOM devices and the cost of system operation, namely, energy loss cost due to both reconfiguration and DSTATCOM placement, are combined to form the objective function to be minimized. The distribution system tie switches, DSTATCOM location and size have been optimally determined to obtain an appropriate operational condition. In the proposed approach, the fuzzy membership function of loss sensitivity is used for the selection of weak nodes in the power system for the placement of DSTATCOM and the optimal parameter settings of the DFACTS device along with optimal selection of tie switches in reconfiguration process are governed by genetic algorithm(GA). Simulation results on IEEE 33-bus and IEEE 69-bus test systems concluded that the combinatorial method using DSTATCOM and reconfiguration is preferable to reduce power losses to 34.44% for 33-bus system and to 45.43% for 69-bus system.

Minimization of Electric Power Losses on 132 kV and 220 kV Uganda Electricity Transmission Lines

The classical minimization of power losses in transmission lines is dominated by artificial intelligence techniques, which do not guarantee global optimum amidst local minima. Revolutionary and evolutionary techniques are encumbered with sophisticated transformations, which weaken the techniques. Power loss minimization is crucial to the efficient design and operation of power transmission lines. Minimization of losses is one way to meet steady grid supply, especially at peak demand. Thus, this paper has presented a gradient technique to obtain optimal variables and values from the power loss model, which efficiently minimizes power losses by modifying the traditional power loss model that combines Ohm and Corona losses. Optimality tests showed that the unmodified model does not support the minimization of power losses on transmission lines as the Hessian matrix portrayed the maximization of power losses. However, the modified model is consistent with the gradient method of optimization, which yielded optimum variables and values from the power loss model developed in this study. The unmodified (modified) models for Bujagali-Kawanda 220 kV and Masaka West-Mbarara North 132 kV transmission lines in Uganda showed maximum power losses of 0.406 (0.391) and 0.452 (0.446) kW/km/phase respectively. These results indicate that the modified model is superior to the unmodified model in minimizing power losses in the transmission lines and should be implemented for the efficient design and operation of power transmission lines within and outside Uganda for the same transmission voltages.

Investigation on current loss of high-power vacuum transmission lines with coaxial-disk transitions by particle-in-cell simulations

Coaxial-disk transitions can generate non-uniform magnetic fields and abrupt impedance variations in magnetically insulated transmission lines(MITLs),resulting in disturbed electron flow and non-negligible current loss.In this paper,3 D particle-in-cell simulations are conducted with UNPIC-3 d to investigate the current loss mechanism and the influence of the input parameters of the coaxial-disk transition on current loss in an MITL system.The results reveal that the magnetic field non-uniformity causes major current loss in the MITL after the coaxialdisk transition,and the non-uniformity decreases with the distance away from the transition.The uniformity of the magnetic field is improved when increasing the number of feed lines of a linear transformer driver-based accelerator with coaxial-disk transitions.The number of input feed lines should be no less than four in the azimuthal distribution to obtain acceptable uniformity of the magnetic field.To make the ratio of the current loss to the total current of the accelerator less than 2%at peak anode current,the ratio of the current in each feed line to the total current should be no less than 8%.

The Need for Awareness of Drinking Water Loss Reduction for Sustainable Water Resource Management in Rwanda

Drinking water loss or Non-Revenue Water (NRW) threatens the financial viability of water utilities and sustainable natural water resource management. However, little attention has been paid to quantitative assessment of the spatial distribution of water losses in Rwanda. Therefore, this study focused on the magnitude of water losses, the associated environmental and socio-economic consequences, as well as the potential benefits from water loss reduction in Rwanda. Based on water usage records from the Water and Sanitation Corporation (WASAC) of Rwanda, NRW was calculated for 15 WASAC branches and Provinces, from July 2013 to June 2014, by using the International Water Association (IWA) standard water balance approach. The results highlight an annual NRW of 16,502,198 or 41% of the total water produced, inducing a revenue loss of US$ 8,713,156. In 14 of the 15 WASAC water branches and all Rwandan provinces, the NRW ratios exceed the NRW threshold (10%) recommended by the American Water Works Association (AWWA). Because of the lost revenue, the water facilities may not expand quickly enough to meet the demands of the rapidly growing population. The suggested 50% reduction in NRW would provide additional 8,251,100 m3 of treated water yearly, enough to serve extra 41,925 households or irrigate 661 ha of cropland and save US$ 4,356,579, which would reduce the financial gap in Rwanda’s National Water Improvement Project by more than 24%.

Semi-Markovian Model of Two-Line Queuing System with Losses

In the present paper, to build model of two-line queuing system with losses GI/G/2/0, the approach introduced by V.S. Korolyuk and A.F. Turbin, is used. It is based on application of the theory of semi-Markov processes with arbitrary phase space of states. This approach allows us to omit some restrictions. The stationary characteristics of the system have been defined, assuming that the incoming flow of requests and their service times have distributions of general form. The particular cases of the system were considered. The used approach can be useful for modeling systems of various purposes.

Improved Method of Power Loss and Electric Field Calculations of HVAC Transmission Lines

An improved method for calculating the corona power loss and the ground-level electric field on HVAC transmission lines induced by corona is proposed.Based on a charge simulation method combined with a method of successive images,the proposed method has the number and location of the simulated charges not arbitrary.When the surface electric field of a conductor exceeds the onset value,charges are emitted from corona into the space around,and the space ions and the surface charges on each sub-conductor are simulated by using the images of the other sub-conductors.The displacements of the space ions are calculated at every time step during corona periods in both the positive and the negative half cycles.Several examples are calculated by using the proposed method,and the calculated electric field at the ground level and the corona power loss agree well with previous measurements.The results show that simulating 12 charges in each conductor during 600 time steps in one cycle takes less time while guarantees the accuracy.The corona discharge from a 220 kV transmission line enhances slightly(less than 2%) the electric field at the ground level,but this effect is little from a 500 kV line.The improved method is a good compromise between the time cost and the accuracy of calculation.

基于Triplet Loss和KNN的非侵入式未知负荷识别

针对在接入新负荷时传统非侵入式负荷识别算法会产生误分类的问题,提出一种基于三元组损失(Triplet Loss)和KNN的非侵入式未知负荷识别算法。首先,采用负荷稳态运行时的电流、电压构造多特征融合的彩色V-I轨迹图像;然后,挖掘在线的Semi-Hard样本对,使用Triplet Loss训练神经网络,并得到各样本的特征向量;最后,对特征向量进行PCA降维,并基于类中心构造邻域,使用KNN算法来进行负荷识别。使用PLAID、COOLL数据集对所提算法进行测试。测试结果表明,所提的负荷识别算法在已知类别负荷的分类和未知负荷的识别方面均有较高的准确率。

Construction of New Value Chain Management and Various BOMs for Research Project of SDGs Food Loss Reduction:Case Studies on Circular Economy Sweets Product Planning,Sales Event Holding,and Questionnaire Surveys

Regarding the social problem of food loss in Japan,about 10%-20%of agricultural products(e.g.vegetables and fruits)are seen as“non-standardized foods”or“surplus foods”by the Agricultural Cooperative Association.Those foods are then discarded.The Tamaki Laboratory of the School of Business,Aoyama Gakuin University is promoting the“SDGs Food Loss Regeneration Project”through industry and academic collaboration—as a research study—to solve this social problem.Therefore,the purpose of this research is the following three subjects:(1)Indicate the design of VCM(value chain management).VCM corresponds to the planning,manufacturing,and sales meetings of“SDGs Moist Vegetable Cake”,and the roles of stakeholders engaged in each area of VCM.(2)Design various BOMs(bill of materials)corresponding to the VCM.Describe how to use BOM and the significance of using each BOM in cooperation.(3)In order to verify the effectiveness of the“SDGs Food Loss Regeneration Project”with“SDGs Moist Vegetable Cake”,conduct and analyze questionnaire surveys and consider the results.

The Difference of the Copy Number Variation and Loss of Heterozygosity of Human Lung Large Cell Cancer Cell Line with Different Metastatic Potential

Background and Objective It has been proven that copy number gain/or loss (copy number variation CNV) in uences gene expression and result in phenotypic variation by

Endoscopic therapy for weight loss: Gastroplasty, duodenal sleeves, intragastric balloons, and aspiration

A new paradigm in the treatment of obesity and metabolic disease is developing. The global obesity epidemic continues to expand despite the availability of diet and lifestyle counseling, pharmacologic therapy, and weight loss surgery. Endoscopic procedures have the potential to bridge the gap between medical therapy and surgery. Current primary endoscopic bariatric therapies can be classified as restrictive, bypass, spaceoccupying, or aspiration therapy. Restrictive procedures include the USGI Primary Obesity Surgery Endolumenal procedure, endoscopic sleeve gastroplasty using Apollo Over Stitch, Trans Oral GAstroplasty, gastric volume reduction using the ACE stapler, and insertion of the TERIS restrictive device. Intestinal bypass has been reported using the EndoB arrier duodenal-jejunal bypass liner. A number of space-occupying devices have been studied or are in use, including intragastric balloons(Orbera, Reshape Duo, Heliosphere BAG, Obalon), Transpyloric Shuttle, and Sati Sphere. The Aspire Assist aspiration system has demonstrated efficacy. Finally, endoscopic revision of gastric bypass to address weight regain has been studied using Apollo Over Stitch, the USGI Incisionless Operating Platform Revision Obesity Surgery Endolumenal procedure, Stomaphyx, and endoscopic sclerotherapy. Endoscopic therapies for weight loss are potentially reversible, repeatable, less invasive, and lower cost than various medical and surgical alternatives. Given the variety of devices under development, in clinical trials, and currently in use, patients will have multiple endoscopic options with greater efficacy than medical therapy, and with lower invasiveness and greater accessibility than surgery.

Footprint of harmful substances in spent pot lining of aluminum reduction cell

Spent pot lining(SPL) from aluminum reduction cells is considered to be hazardous materials due to containing a large amount of soluble fluoride salts and trace toxic cyanides. The distribution of fluorides and cyanide in a 350 kA cell operated for 2396 days was analyzed and the footprint and corrosion mechanism of the harmful substances in SPL were also studied. It is found that the fluorides are mainly concentrated in the cathode carbon block and the layer of dry barrier under the cathodes, which is closely related to permeability of the cathodes and dry barrier the fluorides penetrate in. Cyanide has a low concentration in the cell center and a high concentration in the sidewall, which is positively related to the air amount entering into the areas in the cells.

loss-averse测度的低碳闭环供应链最优减排研究

以低碳产品销售为不确定市场环境为背景,以Stackelberg博弈理论为方法,以loss-averse为工具,构建了双第三方回收低碳风险再制造闭环供应链模型,研究了制造商低碳减排能力、碳排放征税政策、销售商风险厌恶程度和废旧低碳产品回收市场竞争特性等因素的影响作用机理;揭示非合作博弈和协调运作下,订单数量、交易价格、低碳废旧产品回收价格等重要变量和节点企业收益、期望效用及整个链条收益的变化规律及隐含的经济意义与管理理念。设计正向渠道收益共享、逆向渠道风险共担契约,克服风险规避效应和双重边际效应的不利影响,实现低碳再制造闭环供应链的协调;通过数值仿真研究和灵敏度分析,验证了低碳风险再制造闭环供应链模型的有效性及实用性,为供应链上下游企业开展低碳减排合作提供了理论依据和政策建议。

A hypothesis study on bionic active noise reduction of auditory organs

Background:Noise exposure can lead to hearing loss and multiple system dysfunctions.As various forms of noise exist in our living environments,and our auditory organs are very sensitive to acoustic stimuli,it is a challenge to protect our hearing system in certain noisy environments.Presentation of the hypothesis:Herein,we propose that our hearing organ could serve as a noise eliminator for high intensity noise and enhance acoustic signal processing abilities by increasing the signal-noise ratio.For suprathreshold signals,the hearing system is capable of regulating the middle ear muscles and other structures to actively suppress the sound level to a safe range.Testing the hypothesis:To test our hypothesis,both mathematic model analyses and animal model studies are needed.Based on a digital 3D reconstructed model,every structure in the auditory system can be analyzed and tested for its contribution to the process of noise reduction.Products manufactured by this bionic method could be used and verified in animal models and volunteers.Implications:By mimicking the noise-reduction effect of the sophisticated structures in the hearing system,we may be able to provide a model that establishes a new active-sound-suppression mode.This innovative method may overcome the limited capabilities of current noise protection options and become a promising possibility for noise prevention.

Evaluation of C and P Factors in Universal Soil Loss Equation on Trapping Sediment: Case Study of Santubong River

Universal Soil Loss Equation (USLE) is the most comprehensive technique available to predict the long term average annual rate of erosion on a field slope. USLE was governed by five factors include soil erodibility factor (K), rainfall and runoff erodibility index (R), crop/vegetation and management factor (C), support practice factor (P) and slope length-gradient factor (LS). In the past, K, R and LS factors are extensively studied. But the impacts of factors C and P to outfall Total Suspended Solid (TSS) and % reduction of TSS are not fully studied yet. Therefore, this study employs Buffer Zone Calculator as a tool to determine the sediment removal efficiency for different C and P factors. The selected study areas are Santubong River, Kuching, Sarawak. Results show that the outfall TSS is increasing with the increase of C values. The most effective and efficient land use for reducing TSS among 17 land uses investigated is found to be forest with undergrowth, followed by mixed dipt. forest, forest with no undergrowth, cultivated grass, logging 30, logging 10^6, wet rice, new shifting agriculture, oil palm, rubber, cocoa, coffee, tea and lastly settlement/cleared land. Besides, results also indicate that the % reduction of TSS is increasing with the decrease of P factor. The most effective support practice to reduce the outfall TSS is found to be terracing, followed by contour-strip cropping, contouring and lastly not implementing any soil conservation practice.

Higher-Order Line Element Analysis of Potential Field with Slender Heterogeneities

Potential field due to line sources residing on slender heterogeneities is involved in various areas,such as heat conduction,potential flow,and electrostatics.Often dipolar line sources are either prescribed or induced due to close interaction with other objects.Its calculation requires a higher-order scheme to take into account the dipolar effect as well as net source effect.In the present work,we apply such a higher-order line element method to analyze the potential field with cylindrical slender heterogeneities.In a benchmark example of two parallel rods,we compare the line element solution with the boundary element solution to show the accuracy as a function in terms of rods distance.Furthermore,we use more complicated examples to demonstrate the capability of the line element technique.

NRN1 and CAT Gene Polymorphisms, Complex Noise, and Lifestyles interactively Affect the Risk of Noise-induced Hearing Loss

Objective The effects of interactions between genetic and environmental factors on the noise-induced hearing loss(NIHL)are still unclear.This study aimed to assess interactions among gene polymorphisms,noise metrics,and lifestyles on the risk of NIHL.Methods A case-control study was conducted using 307 patients with NIHL and 307 matched healthy individuals from five manufacturing industries.General demographic data,lifestyle details,and noise exposure levels were recorded.The Kompetitive allele-specific polymerase chain reaction(KASP)was used to analyze the genotypes of 18 SNPs.Results GMDR model demonstrated a relevant interaction between NRN1 rs3805789 and CAT rs7943316(P=0.0107).Subjects with T allele of rs3805789 or T allele of rs7943316 had higher risks of NIHL than those with the SNP pair of rs3805789-CC and rs7943316-AA(P<0.05).There was an interaction among rs3805789,rs7943316,and kurtosis(P=0.0010).Subjects exposed to complex noise and carrying both rs3805789-CT and rs7943316-TT or rs3805789-CT/TT and rs7943316-AA had higher risks of NIHL than those exposed to steady noise and carrying both rs3805789-CC and rs7943316-AA(P<0.05).The best six-locus model involving NRN1 rs3805789,CAT rs7943316,smoking,video volume,physical exercise,and working pressure for the risk of NIHL was found to be the interaction(P=0.0010).An interaction was also found among smoking,video volume,physical exercise,working pressure,and kurtosis(P=0.0107).Conclusion Concurrence of NRN1 and CAT constitutes a genetic risk factor for NIHL.Complex noise exposure significantly increases the risk of NIHL in subjects with a high genetic risk score.Interactions between genes and lifestyles as well as noise metrics and lifestyles affect the risk of NIHL.

Proton loss of inner radiation belt during geomagnetic storm of 2018 based on CSES satellite observation

The proton distribution in inner radiation belt is often affected by strong geomagnetic storm disturbance.Based on the data of the sun-synchronous CSES satellite,which carries with several high energy particle payloads and was launched in February 2018,we analyzed the extensive proton variations in the inner radiation belt in a wide energy range of 2 MeV-220 MeV during 2018 major geomagnetic storm.The result indicates that the loss mechanism of protons was energy dependence which is consistent with some previous studies.For protons at low energy 2 MeV-20 MeV,the fluxes were decreased during main phase of the storm and did not come back quickly during the recovery phase,which is likely to be caused by Coulomb collision due to neutral atmosphere density variation.At higher energy 30 MeV-100 MeV,it was confirmed that the magnetic field line curvature scattering plays a significant role in the proton loss phenomenon during this storm.At highest energies>100 MeV,the fluxes of protons kept a stable level and did not exhibit a significant loss during this storm.