Low Production Efficiency Research Articles

Impact analysis of operating conditions on carbon dioxide reduction in microbial electrosynthesis: Insight into the substance utilization and microbial response

Microbial electrosynthesis (MES) is facing a series of problems including low energy utilization and production efficiency of high value-added products, which seriously hinder its practical application. In this study, a more practical direct current power source was used and the anaerobic activated sludge from wastewater treatment plants was inoculated to construct the acetic acid-producing MES. The operating conditions of acetic acid production were further optimized and the specific mechanisms involving the substance utilization and microbial response were revealed. The optimum conditions were the potential of 3.0 V and pH 6.0. Under these conditions, highly electroactive biofilms formed and all kinds of substances were effectively utilized. In addition, dominant bacteria (Acetobacterium, Desulfovibrio, Sulfuricurvum, Sulfurospirillum, and Fusibacter) had high abundances. Under optimal conditions, acetic acid-forming characteristic genera (Acetobacterium) had the highest relative abundance (Biocathode-25.82 % and Suspension-17.24 %). This study provided references for the optimal operating conditions of MES and revealed the corresponding mechanisms.

Research on Fracturing Technology for Low Production and Low Efficiency Casing Damaged Wells

With the further development of Daqing Oilfield, the proportion of casing damaged wells is increasing day by day, because the casing damage location is mostly located in the upper part of the reservoir, the conventional technology can not carry out targeted fracturing construction,the low-yield and low-efficiency wells which limits the efficient development of the oil field. In order to satisfy the needs of subdivision and large-scale fracturing construction of low-yield and low-efficiency wells with casing damage, this paper studied the fracturing design principles, determined the optimal design theory of different types of wells, and can make effective fracturing schemes for different reservoirs and well conditions. At the same time, a kind of small diameter segmented fracturing tools have been developed, which can meet the fracturing operation of wells with diameter above 104mm, so that the number of fracturing segments and the scale of reconstruction are greatly higher than those of conventional technology. 30 wells have been tested in the field, and the effect of increasing oil and injection is obvious. The results show that this process can effectively improve the production status of casing damage, low production and low efficiency wells and increase the productivity of single wells.

Analysis of a cusped helicon plasma thruster discharge

Experiments and simulations are used to analyze a compact helicon plasma thruster with a cusp in its internal magnetic field. The former rely on a compensated Langmuir probe and a Faraday cup, while the latter employ a hybrid PIC/fluid transport model combined with a frequency-domain electromagnetic field model. Measurements serve to tune the anomalous transport parameters of the model and overall show the same trends as the numerical results, including a secondary peak of electron temperature downstream in the magnetic nozzle, where electron cyclotron resonance conditions for the 13.56 MHz excitation frequency are met. The cusp plays a central role in determining the plasma losses to the walls and the profile of electron temperature, which in turn defines the excitation and ionization losses. While losses to the rear wall are reduced, losses to the lateral wall are increased, which, together with the low production efficiency, limit the performance of the device.

Stochastic Frontier Analysis of Production, Socio-economic and Institutional Factors Affecting Technical Efficiency of Cowpea Production in Chuka Sub-county, Kenya

Cowpea is one of the most important vegetable that ranks third among pulses and top five leafy vegetables consumed in Sub Saharan Africa. In Kenya cowpea contributes to cheap supply of nutritious food, revenue and food security. Despite its importance, cowpea production levels are a fraction of the potential due to low technical efficiency of production which affects the revenue levels and food security of the smallholder farmers. This study aimed to determine the production, socio-economic and institutional factors affecting the level of technical efficiency among smallholder cowpea farmers in Chuka Sub County, Tharaka Nithi County, Kenya. Using semi structured questionnaire in a population of 12905 households and using multistage sampling technique from 389 households cross-sectional data on production factors, socioeconomic and institutional characteristics was collected. Data collected was analyzed using descriptive statistics and stochastic frontier production function. The results indicated that production factors, socioeconomic and institutional characteristics significantly affected cowpea production. The mean technical efficiency index was 0.34. The stochastic frontier analysis revealed that production factor coefficients of labour (0.825), topdressing fertilizer (0.635), manure (0.325), agrochemicals (0.221) and land size (0.628) were all positive and statistically significant at 5% level. The inefficiency model revealed that the coefficients of socio-economic factors age (0.038), education (-0.156) and farming experience (-0.053), and the institutional factors, information sources/extension contact (-0.669) and access to digital financial services (1.527) were negative but statistically significant, except for age and access to digital service that were positive and significant. These variables were the determinants of technical efficiency in cowpea production. The results suggest that there is potential for cowpea farmers to increase production and net profits in the long run by efficient utilization of the existing mix of production inputs and technologies. Formulation of policies revolving around the significant variables, input supply, technology transfer and subsidies; extension services, information exchanges and market linkages are recommended to palliate technical inefficiency in cowpea production among farmers.

Intelligent dustbin based on convolution neural network, spectroscopy and internet of things

Aiming at the problems of low level of intelligent automation of garbage classification, low flexibility, low efficiency, high cost and difficulty in large-scale production, this paper proposes a multimodal data fusion intelligent garbage bin system based on neural network, spectral technology and ultrasonic technology, which can effectively classify and recover different types of garbage. This paper mainly includes the following aspects: (1) The accuracy of MobileNetV2 was improved to 76.3% by using an experimental research method; (2) The near-infrared spectrum was studied by literature study and simulation method, and the characteristic wavelength reflectance ratio was used to establish the model; (3) The literature research method and quantitative analysis method were used to judge the types of solid and liquid waste according to the cavitation effect; (4) Integrate the above three technologies and design the corresponding intelligent trash can model, so that the system can perform multimodal data fusion according to the items put by users, jointly determine their categories and assign them to the corresponding categories of trash cans.

Research and Simulation of Kinematics and Dynamics of Tracked Support Equipment Based on Multi-Body Dynamics

Aiming at addressing the problems of low production efficiency and low safety factors in coal mines, this study designed a new type of support equipment and verified its theoretical reliability through the analysis of driving theory. The analysis was carried out through kinematics and dynamics, the position coordinates of the prototype at different times were analyzed using the RPY angles, and the spatial coordinate system of the prototype was established. Then, the position coordinates at different times could be solved by establishing the plane kinematics equations of the prototype. A 14-degree-of-freedom dynamic system model was established to reflect the longitudinal dynamic characteristics of the traveling mechanism of the prototype, and the differential equations of the traveling mechanism were established via the Lagrange dynamic equation method. Finally, the dynamic stability of the prototype under different working conditions was studied by using multi-body dynamic simulation technology. The research results show that the prototype meets the design requirements, has good reliability, realizes the mechanization, automation and high-efficiency production of coal mines, and realizes safe underground production. The research results provide effective solutions for ensuring the sustainable development of coal resources and the safe production of coal mines.

Application of Three-Dimensional Printing Technology to the Manufacture of Petroleum Drill Bits

Drill bits are the main rock-breaking tools in the petroleum and gas industry. Their performance directly affects the quality, efficiency, and cost of drilling. Drill bit manufacturing mainly employs traditional mold forming processes such as milling molding and press molding, which have low production efficiency and long processing cycles and are not conducive to rapid responses to field requirements. Inadequate production accuracy makes it difficult to produce drill bits with complex structures. Three-dimensional (3D) printing technology has fast molding speeds and high molding accuracy. In this paper, 3D printing was applied for the first time to the manufacture of molds for carcass polycrystalline diamond compact (PDC) drill bits and PDC–cone hybrid drill bits. In comparison with forging and milling molding, 3D printing improved production efficiency. The manufactured molds had higher machining accuracy. The ability of 3D printing to make molds with complex surfaces enables the development of drill bits with complex structures. A field experiment was conducted on a PDC drill bit produced by 3D printing, which had a higher rate of penetration and was more efficient in breaking rocks than bits manufactured by traditional processes. The ROP of the drill bit increased by 20.1–25.8%, and the drilling depth increased by 7.7–29.5%. It is therefore feasible to apply 3D printing to the manufacture of petroleum drill bits.

Multichamber PLGA Microparticles with Enhanced Monodispersity and Encapsulation Efficiency Fabricated by a Batch‐Microfluidic Hybrid Approach

Microparticles with multiple internal chambers hold great promise as drug delivery systems due to their ability to sustain the release of drugs with short half‐lives. However, conventional batch methods used for their fabrication have limitations in terms of encapsulation efficiency and particle size distributions, while microfluidic methods suffer from low production efficiency. Herein, a batch‐microfluidic hybrid method is presented for fabricating poly(DL‐lactic‐co‐glycolic acid) (PLGA) polymeric microparticles with uniformly distributed, multiple inner microchambers. A scalable batch method is utilized for primary water‐in‐oil (W/O) emulsions, combined with a precise microfluidic approach for generating controlled secondary emulsions. This approach results in highly uniform PLGA microparticles with tunable size and improved encapsulation efficiency. Additionally, the effect of polydopamine‐based surface hydrophilic modification of microfluidic channels on drug encapsulation efficiency is investigated, achieving an efficiency of approximately 85%. The prepared multichamber PLGA microparticles exhibit an extended‐release profile without initial burst release, demonstrating their potential for sustained drug delivery in various biomedical applications.

Numerical simulation and experimental study on hot rolling forming of spur face gears

Face gear transmission is the transmission mechanism composed of cylindrical gear and face gear. At present, the tooth making method of face gear is still tooth cutting, with low material utilization and low production efficiency. The metal streamlines are cut off, resulting in low fatigue strength of gear teeth. In this paper, the forming of hot rolling was numerically simulated, with which the characteristics of equivalent stress field, equivalent strain field, rolling force variation, and metal flow in the process of rolling were analyzed. Finally, a hot rolling experimental device was set up, by which the face gear test piece was rolled. Then its tooth surface precision was investigated. The research reveals that hot rolling spur face gears is technological feasible and has promising prospects in industrial applications.

Continuous Extrusion Forming Technology of Magnesium Alloy Thin-Walled Tubules.

This paper proposes a new technology of superimposed billet extrusion-forming for thin-walled magnesium alloy tubes. This process represents an improvement over the current technology, which suffers from low production efficiency, poor forming accuracy, and low material utilization. We developed a detailed forming process and mold structure, in which the excess material of the front billet is extruded out of the mold as the rear billet pushes on the front one. Through continuous extrusion, online direct water cooling, and cutting, the automated continuous production of thin-walled tubules is achieved. The optimization of the mandrel structure and its hovering action is also included, with the aim of improving the lifespan of the mandrel and the accuracy of tube size. The numerical simulation method evaluates the effect of the die angle (α) on the tube, formed using FORGE NXT 1.1. The results show that for an angle of less than 70°, the defect length of the tube decreases as the die angle decreases, forming an ordered flow of superimposed billets. If the angle is less than 50°, the two adjacently formed tubes separate automatically, with no need for the subsequent cutting process. The best choice of die angle is about 50°, which takes into account the effect of the change in extrusion force.

3D-printed dosage forms for oral administration: a review.

Oral administration is the most commonly used form of treatment due to its advantages, including high patient compliance, convenient administration, and minimal preparation required. However, the traditional preparation process of oral solid preparation has many defects. Although continuous manufacturing line that combined all the unit operations has been developed and preliminarily applied in the pharmaceutical industry, most of the currently used manufacturing processes are still complicated and discontinuous. As a result, these complex production steps will lead to low production efficiency and high quality control risk of the final product. Additionally, the large-scale production mode is inappropriate for the personalized medicines, which commonly is customized with small amount. Several attractive techniques, such as hot-melt extrusion, fluidized bed pelletizing and spray drying, could effectively shorten the process flow, but still, they have inherent limitations that are challenging to address. As a novel manufacturing technique, 3D printing could greatly reduce or eliminate these disadvantages mentioned above, and could realize a desirable continuous production for small-scale personalized manufacturing. In recent years, due to the participation of 3D printing, the development of printed drugs has progressed by leaps and bounds, especially in the design of oral drug dosage forms. This review attempts to summarize the new development of 3D printing technology in oral preparation and also discusses their advantages and disadvantages as well as potential applications.

A tumor microenvironment-activatable nanoplatform with phycocyanin-assisted in-situ nanoagent generation for synergistic treatment of colorectal cancer

The in-situ generation of therapeutic agents in targeted lesions is promising for revolutionizing oncotherapy but is limited by the low production efficiency. Given the specific tumor microenvironment (TME) of colorectal cancer (CRC), i.e., mild acidity, overexpressed H2O2, glutathione (GSH) and H2S, we develop phycocyanin (PC) encapsulated PZTC/SS/HA nanocapsules (NCs) for TME-responsive, protein-assisted “turn-on’’ therapy of CRC. The NCs are prepared by sequentially assembling Cu2+-tannic acid (TA) coordination shell, disulfide bond-bearing cross-linker, and hyaluronic acid (HA) on the sacrificial template ZIF-8, thus achieving pH-, GSH-responsiveness, and tumor targeting capability, respectively. Once reaching the CRC sites, the NCs can quickly disintegrate and release Cu2+ and PC, accompanied by subsequent endogenous H2S-triggered generation of copper sulfide (CuS). Significantly, the intracellular sulfidation process can be accelerated by PC, thereby enabling efficient photothermal therapy (PTT) under NIR-Ⅱ laser. Besides, Cu2+-associated chemodynamic therapy (CDT) can be simultaneously activated and enhanced by PTT-induced local hyperthermia and disulfide bond-induced GSH consumption. This CRC-targeted and TME-activated synergistic PTT/CDT strategy displays high therapeutic efficacy both in vitro and in vivo, which can open up a new avenue for biomolecule-assisted in-situ nanoagent generation and effective TME-responsive synergistic treatment of CRC.

Biomimetic chlorophyll derivatives-based photocatalytic fabric for highly efficient O2 production via CO2 and H2O photoreaction

As global warming and greenhouse gas emissions intensify, the scientific community is continuingly seeking effective solutions. One promising strategy known as artificial photosynthesis is proposed utilizing H2O as a reducing agent to transfer CO2 into fuel. However, low O2 production and conversion efficiency have hindered this approach in matching with natural photosynthesis. In this work, we propose a novel biomimetic photocatalyst design approach to improve the catalytic efficiency by slow photon mechanism. Our design is mainly inspired by two factors: 1) Chlorophyll, an abundant natural photosynthetic pigment, can efficiently and selectively reduce carbon dioxide and plays a key role in photosynthesis; 2) The iridoplast with a biological photonic crystal structure can significantly improve the efficiency of photosynthesis. Specifically, we couple photonic crystals and photocatalyst of sodium copper chlorophyllin (ChlCu), and binder of PVA through microfluidic blowing-spinning (MBS) to spray a composite photocatalytic film that can convert carbon dioxide and water into carbon monoxide and oxygen. By optimizing the content of ChlCu and the slow photon effect related to the bandgap position, the final CLPPs300-0.52% has two slow photon edges overlapping with the catalyst absorption spectrum, thus generating the maximum photon capture capability and achieving a high oxygen catalytic yield of up to 7.8 mmol g-1h−1. The spraying property of this material enable it to be coated on the external surfaces of other materials. This opens new possibilities of photocatalytic fabric preparation for CO2 converting, providing new ideas of greenhouse gas capture and utilization to solve environmental problems.

Volatile fatty acids bio-production using extracellular polymeric substances disengaged from sludge for carbon source recycling

Excessive waste-activated sludge (WAS) and insufficient carbon source (CS) for biological nitrogen removal (BNR) often coexist in municipal sewage treatment. Although the production of volatile fatty acids (VFAs) from WAS has been recognized as a promising solution, the development is limited by low VFAs production efficiency and dewatering deterioration of sludge. This study extracted the extracellular polymeric substances (EPS) from sludge by low-temperature thermal-hydrolysis (LTH) and high-speed hydro-cyclone (HSHC) pretreatment and recovered it for high-quality VFAs bio-production in thermophilic fermentation. Microbial mechanism analysis disclosed that interspecific interaction networks composed of functional flora, which accumulate VFAs by bio-converting EPS primarily and supplemented by EPS synthesis, guaranteed the efficient bio-production of VFAs. This process scheme shows promise in providing alternative denitrification CSs and avoiding deterioration of sludge dewaterability.

Intelligent Automation Manufacturing for Betula Solid Timber Based on Machine Vision Detection and Optimization Grading System Applied to Building Materials

Wood material is the foundation of wood structure architecture, and its production technology and equipment technology decide the development and upgrading of modern wood structure architecture. Aiming at the problems of low automation degree, low material utilization rate, low production efficiency and high labor costs in the process of traditional wood processing, we explore the integration and innovation of the traditional wood processing industry and modern industrial Internet information technology on the basis of studying the properties of Betula (Betula costata) solid wood materials, wood comprehensive utilization rate, wood structure component development and processing technology requirements, and form an intelligent, automatic and industrial production mode for building materials. Through technology and methods such as mechanical design, automation technology, machine vision, deep learning, optimization algorithm, electronic design automation, computer aided manufacturing, etc., the key technologies of intelligent automatic optimization of wood materials were studied, and intelligent automatic production lines of Betula species identification, log optimization sawing, solid timber longitudinal multiblade sawing, sawn timber quality detection and solid timber optimizing cross-cuts are built. Based on the machine vision method, features are extracted; a tree species, defect classification and recognition model database is established; an image processing algorithm with high recognition accuracy, as well as fast processing speed and high robustness are studied; non-destructive testing and classification methods of machine vision are optimized; key problems of online rapid classification, detection and optimization of sawing are solved and production quality and processing efficiency are improved. Finally, the timber defect detection accuracy and Betula timber yield are analyzed, and the comprehensive utilization value of optimized sawing timber is compared with the comprehensive utilization value of manually marking sawing timber. The processing cost and efficiency of Betula sawing timber with an intelligent automatic production line are calculated. The test results show that the average detection accuracy of timber defect type, size and location is 89.69%, 89.69%, 92.25% and 82.29%, respectively, and the detection stability is high. By adopting intelligent automatic detection, classification and optimization sawing production line of wood, the comprehensive utilization value of optimized sawing timber is 14.13% higher than that of manual marking sawing timber, and 16,089.29 m3 more building materials can be processed annually. In the process of intelligent automatic wood processing, the intelligent detection system is used to detect defects, improve production performance and production efficiency and reduce labor costs. Compared with the traditional wood processing process, the method studied in this paper is improved to optimize the production line processing performance and processing technology. The research and development of an intelligent automatic production system for solid wood can promote the application and development of an automatic industrial production mode for sawn timber for the wood structure construction industry, deepen the integration of artificial intelligence technology, Internet technology and the whole wood processing industry and lead the upgrading of building materials for wood structures to an intelligent manufacturing production mode.

Surface defect classification of hot-rolled steel strip based on mixed attention mechanism

PurposeThis paper aims to propose a classification method for steel strip surface defects based on a mixed attention mechanism to achieve fast and accurate classification performance. The traditional method of classifying surface defects of hot-rolled steel strips has the problems of low recognition accuracy and low efficiency in the industrial complex production environment.Design/methodology/approachThe authors selected min–max scaling comparison method to filter the training results of multiple network models on the steel strip surface defect data set. Then, the best comprehensive performance model EfficientNet-B0 was refined. Based on this, the authors proposed two mixed attention addition methods, which include squeeze-excitation spatial mixed module and multilayer mixed attention mechanism (MMAM) module, respectively.FindingsWith these two methods, the authors achieved 96.72% and 97.70% recognition accuracy on the steel strip data set after data augmentation for adapting to the complex production environment, respectively. Using the transfer learning method, the EfficientNet-B0 based on MMAM obtained 100% recognition accuracy.Originality/valueThis study not only focuses on improving the recognition accuracy of the network model itself but also considers other performance indicators of the network, which are rarely considered by many researchers. The authors further improve the intelligent production technique and address this issue. Both methods proposed in this paper can be applied to embedded equipment, which can effectively improve steel strip factory production efficiency and reduce material and time loss.

Collaboration between Oil Development and Water/Power Consumption in High-Water-Cut Oilfields

Waterflooding is the main development technique used in the vast majority of oilfields in the world. However, as the waterflood oilfields enter the stages with (ultra-)high water cut, the water/power consumption per ton of oil remains unabatedly high. This paper presents a systematic analysis of the development stages and strategies of some typical waterflood oilfields in the world and proposes the necessity to establish a mode and technical system of collaboration between oil development and water/power consumption in mature oilfields with (ultra-)high water cut. Then, taking a pilot test area of an ultra-high-water-cut oilfield in northeastern China as an example, this paper investigates its development mode and water/power consumption; optimizes the technical strategies from the aspects of fine reservoir analysis, artificial lift system and surface gathering system; and predicts the application results. It is found that the optimizations of fine reservoir analysis and development plans effectively reduce the water consumption per ton of oil and have a certain but not remarkable contribution to the power consumption per ton of oil. Moreover, the optimizations of the artificial lift system and surface gathering system significantly reduce the power consumption per ton of oil. Under conditions of low production and low efficiency, the optimization of the artificial lift system greatly improves the energy-saving effect, which will be a focus of future research. Finally, this paper recommends measures for collaboration between oil development and water/power consumption in high-water-cut oilfields.

Building Competitive Advantage Through Strategy Map and Balanced Scorecard in Improving Company Performance

The purpose of this research is to identify strategy maps for PT. TA company based on the problems faced by the company, to identify the right balanced scorecard design for PT. TA, to find out the best competitive strategy that can be used by PT. TA to be able to compete with other heavy equipment rental companies in Central Java. The research approach used is a qualitative research method. The results show PT. TA faces problems of dependence on a single product, low production efficiency, and high production costs. To overcome this, they can implement several strategies. First, they can open new markets or explore markets that have not been optimally exploited through a map strategy. In addition, they can also develop new products or product variations of existing products, as well as product diversification. In addition, companies need to improve production processes, increase the efficiency of resource use, improve product quality, and improve production technology in order to reduce high production costs and increase production efficiency. By implementing these strategies, PT. TA can increase competitiveness and ensure the continuity of the company's business in the long term. PT. TA can adopt a Balanced Scorecard (BSC) design to continuously monitor strategy implementation. By using BSC, companies can ensure that all important aspects of business are well integrated in the company's strategy. Business goals can be achieved in a directed and measurable manner through the implementation of the BSC.

Fe/Mn modified biochar as electrode particles in electrochemical system for efficient anaerobic sludge digestion

Electrochemical pretreatment (EPT) of sewage sludge demonstrates an aggressive effect on extracellular polymeric substance destruction and sludge solubilization. While the low efficiency of methane production does not match the initial dissolution of the sludge after EPT. Here we proposed a novel method, using Fe-Mn-modified biochar (FMBC) strengthening electrochemical pretreatment, aiming at improving the methanogenic efficiency. The strengthening mechanism of FMBC was studied according to the physicochemical parameters of sludge at different concentrations and the change of microbial community. Experimentally, with the addition of 2 g/L FMBC, the methane production increased by 7.96% and 10.06% compared with electrochemical pretreatment alone and the control group. The sludge organic matter solubilization varied from 344.6 mg/L in E0 to 383.4 mg/L in E2 after pretreatment. Simultaneously, analysis of microbial communities showed that the addition of 2 g/L FMBC obviously increased the relative abundance of Methanofastidiosum and Methanosaeta from 5.5% and 20.9% in CK to 16% and 28.7% in E2, respectively. The addition of FMBC also intensified the acetoclastic methanogenesis and methylotrophic methanogenesis. This study provides new ideas for the enhancement of electrochemical pretreatment of sludge.

CNC machining optimization of hydro-turbine runner blade based on VERICUT

Aiming at the problem of low production efficiency caused by the unreasonable setting of cutting parameters for CNC machining of hydro-turbine runner blade, the Force module of VERICUT software is used to analyze and compare the cutting force, the cutting power, and the material removal rate of the blade under different cutting parameters, find the cutting parameters that can give full play to the machining capacity of the machine tool, and use the optimization function of Force to automatically adjust the feed speed in the machining program. The test results show that after the optimization of cutting parameters, the production efficiency of the NC machining program is significantly improved, and the cutting power of the machine tool spindle is stable.