Sources Of Inefficiency Research Articles

Heterogeneous strategy and performance decomposition of regional industries in China: From the perspective of resource misallocation

AbstractThe rapid expansion of China's industrial sector has been accompanied by energy consumption and environmental pollution. Accurately identifying the sources of inefficiency of industrial sector is crucial for achieving sustainable development. To address this issue, this study develops a novel decomposition approach that combines the concepts of natural and managerial disposability with an aggregate directional distance function approach to measure the performance of regional industries in China from 2006 to 2019. In the proposed approach, the overall inefficiency is decomposed into technical inefficiency and structural inefficiency. The latter component, which captures inefficiency associated with resource misallocation within a country, is further divided into mix and scale elements. The results show that there remains much room for potential improvement in both the operational and environmental performance of China's industrial system, particularly in the central area. Furthermore, structural inefficiency is the primary contributor to the overall inefficiency of Chinese industry under natural disposability, whereas technical inefficiency appears as the main source of the inefficiency under managerial disposability. The results also reveal great disparities in terms of the overall inefficiency and the sources of inefficiency of Chinese industrial sector among regions between different mitigation strategies. Given the substantial structural effect on the performance of Chinese industries across regions, it is necessary to accelerate the establishment of market mechanisms to promote efficient allocation of resources.

Data Driven Insights to Operating Room Inefficiencies: What’s next? Part 1

Operating rooms are a major source of both revenue and expenses within hospital systems and surgical centers. Over the past two decades, a considerable amount of work has been done to identify and address sources of wastefulness that contribute to operating room inefficiencies. Quality improvement strategies have included surgery scheduling algorithms, Lean and Six Sigma methodologies, patient- centered data, and direct observations of communications and processes. While significant gains in efficiency have been demonstrated, there still exists substantial opportunity for improvement. The purpose of Part 1 of this narrative review is to synthesize the existing research on pre-operative factors that directly impact operating room efficiencies, discuss existing technologies previously used to address these factors, and identify the potential for new technologies capable of data-analytics to further create value within the operating room. Part 2 will cover intra- and post-operative sources of inefficiencies and propose potential technological and data solutions.

Metafrontier slack-based nonparametric technologies with convex and nonconvex measurement of directional distance functions: empirical exploration of high-tech industries

ABSTRACT High-tech industries make an essential contribution to improving innovation ability and promoting industrial structure optimisation. It is essential to examine the development level and regional differences within China's high-tech industry to enhance the quality of economic development. This paper develops a metafrontier slack-based nonparametric method of the directional distance function to perform an efficiency analysis. Distinguishing the development differences of regional high-tech industries and identifying the main causes of inefficiency sources. We are the first to combine convex and nonconvex technologies to calculate group and meta frontier efficiencies, and the technical gap ratio for the high-tech industries. Empirical results indicate that the nonconvex method can provide more reasonable explanations for green innovation efficiency.

Why informationally diverse teams need not form, even when efficient

We introduce a model of team formation in which workers first match and then produce correlated signals about an unknown state. While it is efficient to maximize the number of informationally diverse teams, such teams need not form in equilibrium when output is shared equally. Our analysis identifies the two sources of matching inefficiency: (i) workers may form diverse teams that are beneficial to its members, but force excluded workers to form homogeneous teams, and (ii) even when a diverse team is efficient, a worker may prefer to join a homogeneous team if she can exert less effort than her teammate. We completely characterize each inefficiency.

Airports in Turkey: efficiency limits and the role of technological change

PurposeThis paper aims to present an example of the measurement of airport efficiency, a topic of great interest in civil aviation today. The methodology used is data envelopment analysis (DEA) and the Malmquist Index. The calculation of airport efficiency with up-to-date data for each period is of great importance in the context of sustainability. The study selected ten airports with high air traffic in Turkey as the sample set. The objective of this study is to evaluate the current state of airport efficiency, identify the sources of inefficiency and make appropriate policy recommendations based on the findings obtained.Design/methodology/approachThe study is based on DEA and Malmquist Index Analysis. The number of personnel and terminal size data of ten selected decision-making units (DMU) are used as inputs, while passenger, cargo and aircraft traffic data are used as outputs. A five-year period, spanning from 2018 to 2022, is considered as the data set in the study.FindingsUpon analysis of the data from the ten airports included in the study, it was found that the current input-output combination yielded efficient results, with the exception of certain characteristics, such as the impact of seasonal conditions or tourism. Concurrent with the growth in aircraft, passenger and freight traffic, the number of personnel employed at these airports has also increased. It was concluded that technological efficiency is of paramount importance for each airport, and that investments in technology should be increased.Practical implicationsA separate assessment was conducted for each of the ten airports included in the study sample. Each airport was evaluated in terms of its strengths and weaknesses, and areas of low efficiency were identified. Consequently, more general conclusions were reached than airport-specific evaluations.Originality/valueIn order to ensure the long-term sustainability of the sector, it is essential that the efficiency measurements of airports are calculated using up-to-date data on a regular basis. The results obtained from these calculations provide guidance for the strategic plans to be implemented in the long term, as well as for the solution proposals for operational problems. In this context, this study not only provides information to policymakers and airport managers about the current situation, as it includes recent data, but also contributes to the literature in this sense, as it includes policy recommendations.

Exploiting Non-Classical Nucleation for Improved Gas Bubble Mitigation on Nickel Electrocatalysts for the Oxygen Evolution Reaction

The efficient transport of gas poses a significant challenge in the design of high-performance gas evolving electrocatalysts. Inefficiencies due to mass transport limitations become more pronounced at the high current densities required in industrial electrolyzers, largely as a result of gas bubbles that obstruct a portion of the electrochemically active surface area of the anode and/or cathode, while also hindering electrolyte transport to the electrode surfaces. One promising approach to mitigate these sources of inefficiency is to engineer micro-to-nanoscale surface textures that promote the favorable growth and release of these bubbles. A range of structures have been shown to improve electrocatalyst performance under both stagnant and induced convection conditions, particularly in applications for hydrogen production via electrocatalytic water splitting in alkaline water electrolyzers.1 Trends between surface texture and electrocatalyst performance have been observed for a range of features, such as pillars,2,3 ridges,4 dimples,5 “cracked” structures,6 and electrodeposited crystalline structures,7 however substantial work is still needed to optimize the designs of these materials. These textured surfaces can influence bubble evolution in various ways, such as by altering the wetting properties of a surface, or by providing preferential nucleation sites. Previous studies have noted that surface structures that provide good control over bubble nucleation can often be adversely affected by increased bubble retention.3–5 The present study investigates a method of fabricating patterned electrocatalysts that provides a fine, tunable control over the distribution of bubble nucleation sites on the surfaces of planar Ni electrocatalysts for the oxygen evolution reaction (OER). These textured surfaces are designed to take advantage of so-called “non-classical nucleation” or “type IV nucleation”, a scenario in which gas is trapped at specific surface sites with an effective radius larger than the critical radius for classical nucleation, thereby allowing spontaneous bubble growth without being required to overcome an activation energy barrier.8 The separation between these sites on the surface of the OER active material (i.e., Ni) is then varied to obtain the most favorable distribution of these non-classical nucleation sites. Chronoamperometry is used to compare the current densities achieved by these patterned Ni electrodes to that of a planar Ni electrode. High speed videography is used to directly measure how these textures influence processes such as bubble growth and detachment, and to determine how these processes influence performance. A better understanding of these gas evolution processes can help lower the energy requirements for electrolyzers and may have more general implications for the design of energy efficient gas evolving electrocatalysts relevant to a variety of industrially important reactions.

Optimizing the Performance of Nickel Electrocatalysts with Regular Arrays of Linear Ridge-like Features for Enhancing the Oxygen Evolution Reaction

The oxygen evolution reaction (OER) represents a major source of inefficiency in the production of green hydrogen via electrocatalytic water splitting. At high overpotentials relevant to industrial rates of gas production, bubbles can contribute substantially to these inefficiencies by inhibiting the mass transport of electrolyte and partially obstructing the electrochemically active surface area (Aecsa) of an electrode.1 Arrays of microscale features have been shown to improve the efficiency of gas evolving reactions, including the OER. The performance of electrodes modified with linear ridge-like surface features has been previously observed to increase with the spacing between the ridges with a separation of up to 200 µm, but it was not known whether this trend continues indefinitely.2 The present study utilizes rapid prototyping techniques, including microscope projection photolithography and electrodeposition, to determine whether an optimal ridge separation exists between 200 and 450 µm. At a relatively high overpotential of 1.8 V (vs Hg/HgO) in an alkaline electrolyte, the performance of these ridges was observed to increase up to a critical separation, after which the performance decreased to a level comparable to a planar electrode at a wider separation between the ridges. Chronoamperometry measurements indicated that ridges with this optimal spacing attained a current response nearly 3× that of a planar electrode when normalized to (Aecsa). A better understanding of the reasons for this observed trend was pursued using high speed imaging. Direct observations of bubble production on the surfaces of the electrodes provided a deeper understanding of how the distribution of gas bubbles on an electrode affects performance.

Composition-Dependent Dynamics of Nickel-Iron-Cobalt Metal Catalysts for Oxygen Evolution Reaction

Water electrolyzers, such as proton exchange membrane water electrolyzers (PEM) and anion exchange membrane water electrolyzers (AEM) are important technologies for sustainable electrochemical energy conversion. The oxygen evolution reaction (OER) at the anode is a pivotal half-reaction in these systems. Despite substantial progress over the years, OER kinetics remain a major source of inefficiency in these devices, necessitating the development of stable catalysts. Currently, precious metal-based catalysts dominate the landscape of OER catalysts for these devices. As non-precious alternatives, nickel-iron (Ni/Fe) catalysts have emerged as particularly promising in alkaline conditions. However, they exhibit dynamic behavior during electrocatalysis—for instance, oxidizing to an active oxyhydroxide phase during the OER. This dynamic nature makes it challenging to establish clear structure-activity-stability relationships. Incorporating cobalt (Co) into the catalyst composition has been found to influence the activity and material conversion of mixed Ni-Fe-Co oxides and (oxy)hydroxides. Methods for rationally activating and stabilizing Ni-Fe-based catalysts via electrochemical and chemical (e.g. composition) routes are necessary for enhancing scalability and accessibility in hydrogen production devices.Herein, our goal is to understand and exploit activation protocols to enhance the OER performance of as-synthesized nickel-iron-cobalt metal thin films, addressing three primary objectives: synthesizing and characterizing homogeneous metal catalysts, investigating the impact of different potential ranges and scan rates on catalyst oxidation and surface conversion from the metal, and assessing how the addition of cobalt influences conversion rates and current density of the catalyst. We use cyclic voltammetry to facilitate and disentangle conversion (integrated reductive peak for Ni and/or Co2+ → 3+ transition) and OER performance (current density (mA cm-2) at η = 350 mV). For all compositions tested of (Ni80Fe20)100-xCox, x = 0 - 5 % we observe that the most effective conversion requires both redox and oxygen evolution. To further investigate the relationship between conversion and performance catalysts were tested in varying electrolytes such as 1M KOH, 0.1M KOH, and an ionomer overlayer to understand how these impacted conversion.Subsequently, post-analysis techniques such as X-ray photoelectron spectroscopy (XPS) and inductively coupled plasma mass spectrometry optical emission spectroscopy (ICP-OES) were conducted to gain insights into the surface composition and elemental distribution of the catalysts following potential cycling. Additionally, electrochemical mass spectrometry (EC-MS) was employed to quantify the faradaic efficiency of oxygen, providing an understanding of at what point the catalyst begins converting and how much of the OER current is directed towards OER versus metal conversion.This project advances the fundamental understanding of NiFeCo catalyst conversion, shedding light on the critical role of catalyst composition and investigating the conditions that foster optimal conversion efficiency. The use of physical vapor deposition for thin film catalysts offers distinct advantages, making deposition and scaling processes facile. This capability, coupled with the gained insights into conversion dynamics, sets the stage for in situ optimization of the surface to achieve the active oxyhydroxide phase with the highest performance for AEM water electrolysis.

AN EXPERIMENTAL RIGHT ATRIUM PLATFORM TO ASSESS RECIRCULATION IN HEMODIALYSIS CATHETERS

Hemodialysis (HD) is a treatment supporting decreased kidney function, via a catheter inserted into the heart’s Right Atrium (RA). Recirculation is a source of inefficiency for treatment, where blood is dialyzed again due to poor catheter design. Lab-testing is still relatively unexplored, hence, a mechanical testing system was designed with the intention of providing a consistent and repeatable environment for testing HD catheters. System geometry was composed using a Computer-Aided Design (CAD) model of a heart, with the RA scaled to appropriate dimensions, and a PolyDiMethylSiloxane (PDMS) model produced through 3D printing and negative wax casting. Pulsatile blood flow was mimicked by peristaltic pumps driving a blood analogue (BA). Recirculation was induced by adding dyed BA to the system via the catheter and measured using a colorimeter. The developed platform was initially evaluated using two catheters, demonstrating the capability to accurately replicate atrial hemodynamic conditions. Two step-tipped catheters, A and B, were tested at 350 ml/min, producing recirculation values of 13.11% and 18.58%, respectively. The results exhibit the ability of the system developed to evaluate HD catheter performance, with the potential to explore a wider range of tip geometries relevant to clinical preference. Furthermore, this advancement towards an anatomically accurate lab-based test system could be paired with computational methods to progress the evaluation of such medical devices and enhance their development.

The eco-efficiency of fisheries in EU countries

The main goal of this article was to (1) assess the dynamics of eco-efficiency of fisheries in EU countries and its components and (2) identify potential sources of inefficiencies and efficiency surpluses through slack analysis. The hybrid data envelopment analysis (DEA) model was used for the 2008-2019 period. Progress in eco-efficiency was found among 11 countries (out of 23), but the average eco-efficiency index for the sample was 0.988. Differences in the levels and dynamics of eco-efficiency between the studied countries were mainly driven by the efficiency change component, i.e. internal factors. The largest input-saving potential was found in relation to number of employees and gross tonnage of the vessel, suggesting that sample countries deal with the problem of overinvestment and overstaffing. We also found that greenhouse gas emissions could be reduced by approximately a third.

A Dual-Mode Hybrid System Combining Solar Thermal With Pumped Thermal Energy Storage

A hybrid system that delivers renewable electricity generation and electricity storage capabilities is introduced. This dual-mode hybrid system is based on Pumped Thermal Energy Storage (PTES) which uses a heat pump to convert electricity into thermal energy that is transferred to silica particles which are stored in concrete silos. The stored heat is later converted back to electricity in a heat engine. The heat pump and heat engine use a closed Joule-Brayton cycle and fluidized bed heat exchangers. If the PTES system is co-located with an array of concentrating solar mirrors and a particle receiver, then the silica particles may also be heated up by the concentrating solar power (CSP) system. The PTES heat engine may also be used to convert the stored solar heat into electricity, thereby sharing this system between the PTES and CSP systems and reducing costs. However, this requires careful management of the heat engine off-design parameters. A thermodynamic model is used to evaluate the performance of the dual mode PTES-CSP hybrid system. The model accounts for turbomachinery efficiency, and approach temperature and pressure loss in heat exchangers, as well as other sources of inefficiency, such as motor-generator losses, and air fan power. The hybrid system also requires the evaluation of the turbomachinery efficiency and pressure ratio at off-design conditions since the CSP system operates over different temperature ratios than the Carnot Battery. Several design variables and design modifications are investigated, such as pressure ratios and maximum temperatures.

Longitudinal analysis of production process variability: an organizational information processing theory perspective

PurposeThis study applies organizational information processing theory (OIPT) to investigate managing production process variability in uncertain environments using information technology (IT) capabilities.Design/methodology/approachWe conduct an empirical analysis using the three-stage least squares (3SLS) technique on 1,612 manufacturing firms over ten years.FindingsThe findings show that IT capability plays a dual role: it reduces the positive impact of environmental uncertainty on production process variability and mitigates the negative relationship between production process variability and operational performance.Practical implicationsOur findings suggest that managers should focus on reducing production process variability by strengthening their firms' IT capabilities. This is particularly crucial in volatile environments where external uncertainties can significantly impact operational processes.Originality/valueVariability in the production process is a significant source of inefficiency and disruption within business processes. Using OIPT, our study contributes to the field by empirically analyzing the role of IT capabilities in reducing production process variability under environmental uncertainty.

Exergy analysis of a gas turbine cycle power plant: a case study of power plant in Egypt

This research presents an exergy analysis of a gas turbine power plant situated in Assiut, Egypt, operating under high-temperature conditions. The aim of the study is to assess the performance of the simple gas turbine cycle and identify the sources of thermodynamic inefficiencies using the second law of thermodynamics as a basis for analysis. To accomplish this, a model was developed in EES software utilizing real operational data obtained from the plant's control system. The investigation focused on the impact of varying ambient temperature on the exergy efficiency, exergy destruction, and net power output of the cycle. The results revealed that the combustion chamber accounted for the highest exergy destruction, amounting to 85.22%. This was followed by the compressor at 8.42% and the turbine at 6.36%. The overall energy and exergy efficiencies of the system were determined to be 28.8% and 27.17%, respectively. Furthermore, the study examined the effects of increasing ambient temperature from 0 to 45°C on the system's performance. It was observed that as the temperature rose, the overall exergy efficiency decreased from 27.91 to 26.63%. Simultaneously, the total exergy destruction increased from 126,407 to 138,135 kW. Additionally, the net power output exhibited a decline from 88,084 to 84,051 kW across the same ambient temperature range. These findings highlight the significant influence of ambient temperature on the thermodynamic performance of gas turbine power plants. As temperature rises, a greater amount of exergy is lost, resulting in reduced efficiency and diminished net power output. Therefore, optimizing the design of the combustion chamber is crucial for mitigating the adverse effects of hot weather conditions. The insights obtained from this study can be utilized to enhance the design and operation of gas turbine plants operating in hot climates.

Hawk: Accurate and Fast Privacy-Preserving Machine Learning Using Secure Lookup Table Computation

Training machine learning models on data from multiple entities without direct data sharing can unlock applications otherwise hindered by business, legal, or ethical constraints. In this work, we design and implement new privacy-preserving machine learning protocols for logistic regression and neural network models. We adopt a two-server model where data owners secret-share their data between two servers that train and evaluate the model on the joint data. A significant source of inefficiency and inaccuracy in existing methods arises from using Yao’s garbled circuits to compute non-linear activation functions. We propose new methods for computing non-linear functions based on secret-shared lookup tables, offering both computational efficiency and improved accuracy. Beyond introducing leakage-free techniques, we initiate the exploration of relaxed security measures for privacy-preserving machine learning. Instead of claiming that the servers gain no knowledge during the computation, we contend that while some information is revealed about access patterns to lookup tables, it maintains epsilon-dX-privacy. Leveraging this relaxation significantly reduces the computational resources needed for training. We present new cryptographic protocols tailored to this relaxed security paradigm and define and analyze the leakage. Our evaluations show that our logistic regression protocol is up to 9x faster, and the neural network training is up to 688x faster than SecureML. Notably, our neural network achieves an accuracy of 96.6% on MNIST in 15 epochs, outperforming prior benchmarks that capped at 93.4% using the same architecture.

Sources of Technical Inefficiency for Smallholder Field Pea Producers in Ethiopia

This study intended to measure the technical efficiency and sources of inefficiency for field pea producers in Ethiopia. The study used primary data collected from 207 smallholder farmers. A multi-stage sampling technique was followed to select sample households. A stochastic frontier was the model used, and a single-step estimation approach was followed. The result indicated that the mean technical efficiency is 49.23 %, and the average productivity of the crop is 0.96 tons/hectare. This indicates that the technical efficiency could be increased by 51.77 % through proper utilization of production variables, i.e. agrochemicals, oxen power, plot size, and seed rate. The inefficiency model result also confirmed that the technical inefficiency of field pea production was negatively affected by access to off-farm income, access to credit services, extension contacts, adoption of new technologies, access to training, and participation in contract farming of the crop. Therefore, this study recommends agricultural policies favoring vocational training to farmers on the new agricultural technology packages, availing access to off-farm incomes, facilitating credit services to farmers, and establishing legal frameworks that encourage contract farming.

Plastic and Reconstructive Surgery Resident Indigent Care Clinic Optimization by Improving "No-Show" Rates.

Absenteeism among clinical patients is a significant source of inefficiency in the modern American health care system. Routine absenteeism limits access to care for indigent patients, thus providing additional strain on the health care system and timely administration of care.This quality improvement project set out to quantify, understand, and potentially reduce patient absenteeism in our weekly plastic and reconstructive surgery resident indigent care clinic. One year prior to our study was retrospectively reviewed to determine a baseline rate of absenteeism (no shows). The daily and monthly no-show percentages were calculated. Then, three consecutive 2-month Plan, Do, Study, Act (PDSA) cycles were performed and data were recorded.The initial year analysis demonstrated an average no-show rate of 25%. The first PDSA cycle attempted to ascertain factors contributing to absenteeism and to get patients rescheduled. The rate of clinical absenteeism was 27% over this period compared with a rate of 18% in the control period. During this period, we discovered a limitation of our institution's electronic medical record (EMR). Rescheduled patients were removed from the original schedule and were not counted as a missed appointment even though the opportunity for care was missed. The second PDSA cycle attempted to collect raw data while trying to understand the EMR error and rescheduling process. During this period, there was a 33% no-show rate compared with 27% in the control period. The third PDSA cycle attempted again to establish factors contributing to clinical absenteeism with a better understanding of the limitations of our EMR. A 33% no-show rate during this cycle was recorded compared with 22% in the control period. After three PDSA cycles were completed, our clinic had an average no-show rate of 31% compared with 25% during the same months in the previous year.This project brought to realization that our data were initially skewed by our ignorance of an EMR flaw that did not track patients who either canceled or rescheduled their appointments. We also learned that there is a certain subset of patients who are not able to be contacted and who do not follow up.

Exploring photoexcitation effects on Cs3Bi2Br9 perovskite single crystal properties

Lead-free halide perovskite single crystals (SCs) offer a compelling alternative for optoelectronic devices due to their superior intrinsic properties. Despite advancements in excellent perovskite SCs, analyzing defects remains crucial. This two-fold approach can both enhance device performance and provide insights into the interactions between light-induced carriers and these defects within the material. This work investigates defects in Cs3Bi2Br9 perovskite SCs using photoexcitation. Photocurrent and photocapacitance measurements are employed to analyze these light-induced defects and their influence on the material's properties. The examination of Cs3Bi2Br9 SCs properties alongside a gold electrode involves evaluating both bulk and interfacial defect densities. This assessment is carried out by analyzing the capacitive behavior in response to different wavelengths λR, λG, and λB (λR = 652.54 nm, λG = 539.06 nm, and λB = 413.28 nm). The temporary reaction to light of individual crystals indicates the presence of carrier capture and subsequent recombination processes. The analysis of the response to light under different situations offers insights into potential defect origins within SCs of Cs3Bi2Br9. This extensive optoelectronic investigation unveils a critical connection between light illumination conditions, carrier transport properties, and overall system efficiency. A comprehensive comprehension of light-triggered defects in perovskites could aid in identifying the source of electrical inefficiency and in the creation of exceptionally effective optoelectronic systems.

Fiscal space for the immunisation program in Zambia– an efficiency analysis approach

ObjectiveThe immunisation programme in Zambia remains one of the most effective public health programmes. Its financial sustainability is, however, uncertain. Using administrative data on immunisation coverage rate, vaccine utilisation, the number of health facilities and human resources, expenditure on health promotion, and the provision of outreach services from 24 districts, we used Data Envelopment Analysis to determine the level of technical efficiency in the provision of immunisation services. Based on our calculated levels of technical efficiency, we determined the available fiscal space for immunisation.ResultsOut of the 24 districts in our sample, 9 (38%) were technically inefficient in the provision of immunisation services. The average efficiency score, however, was quite high, at 0.92 (CRS technology) and 0.95 (VRS technology). Based on the calculated level of technical efficiency, we estimated that an improvement in technical efficiency can save enough vaccine doses to supply between 5 and 14 additional districts. The challenge, however, lies in identifying and correcting for the sources of technical inefficiency.

Perfect pairing: use of a radiofrequency-blocking Faraday bag for video capsule deployment

Background and AimsVideo capsule endoscopy (VCE) is a valuable tool for evaluation of small bowel pathology. Video capsule pairing timing is a source of inefficiency. A potential etiology of delayed pairing is interference from external devices. We evaluated the impact of using a radio signal blocking commercially available “Faraday” bag on VCE pairing time. MethodsVCE pairing time was measured for 20 cases with (bag group) and without (control group) the use of a Faraday bag. If cases that started without the Faraday bag did not pair after 10 minutes, they were crossed over to the Faraday bag group. Ambient radiofrequency levels were measured in both groups. ResultsPairing time was 49.3 ± 33.3 seconds in the Faraday bag group versus 384.2 ± 225.6 seconds in the control group (P < 0.001). Among the four control cases that crossed over to the Faraday bag group, pairing time post-bag was 23.5 ± 19.5 seconds. The average radiofrequency level was 0.004 ± 0.006 milliwatts / square meter (mW/m2) in the bag group compared 40.7 ± 48.2 mW/m2 in the control group (P < 0.001). ConclusionsUse of a Faraday bag shortens VCE pairing time, possibly by decreasing radiofrequency interference. This intervention may augment efficiency in the endoscopy suite/clinic.

DEVELOPMENT OF DOWNHOLE PUMP VALVE ASSEMBLY

The purpose of the work is modernization of the valve, in order to increase reliability, wear resistance, increase the pump flow and reduce the load on the rod string, as well as improve durability. The sucker rod pump is one of the most popular and extensively utilized artificial lift systems. It is a frequently chosen option for lifting oil because of its fundamental simplicity, low operating costs, and adaptability in power supply. In the long run of oil production history, sucker-rod pumping was the first option—and frequently the only option—when artificial lift was required. For this reason, the oldest and most popular method of producing oil wells worldwide is sucker-rod pumping. Since the steel used to make rods has limited strength, sucker-rod pumping is typically thought of as a way to raise moderate to low liquid production rates from shallow to medium well depths due to depth restrictions. Since the correct working of the standing and traveling valves is largely responsible for an efficient pumping operation, valves are regarded as the heart of the sucker-rod pump. The extremely high differential pressures across the valve during pumping necessitate a highly dependable sealing action between the ball and the seat. Small initial flaws in the sealing surfaces or subsequent corrosion- or abrasion-related problems result in greater liquid slipping and a quick decline in valve function because of fluid cutting. Subsurface pumps using traditional ball-and-seat valves suffer a number of basic operational issues: • Because of the greatly high number of pumping cycles per day, the sealing surfaces may sustain significant damage from the frequent collision of the two parts against one another. • In deviated wells, valve wear is uneven and can cause premature failure. • Typical cage constructions, meant to limit impact damage, typically restrict the flow area available through the valve and can be the source of pumping inefficiencies due to low fillage of the pump barrel. Keywords: sucker rod pumps, downhole pump, traveling valve, standing valve, valve assembly.