External Operation Research Articles

The effectiveness of the dacryocystorhinostomy operation with physiodispenser in nasolacrimal duct obstruction

ABSTRACT Purpose To evaluate the effectiveness of the dacryocystorhinostomy (DCR) operation with physiodispenser in nasolacrimal duct obstruction. Methods Two hundred and twelve eyes from 150 patients with chronic dacryocystitis who had undergone external DCR operation with Kerrison punch were included in Group 1. Two hundred and fourteen eyes from 150 patients with chronic dacryocystitis who had undergone external DCR operation with physiodispenser were included in Group 2. Results There were no significant differences between the two groups in terms of age and sex (p > .05). Excessive bleeding requiring cauterization was observed in 41 (19%) patients in Group 1 and 8 (3%) patients in Group 2 (p < .05) during surgery. The mean operation duration was 32.36 ± 5.46 (26–42) minutes in the first group and 20.41 ± 4.98 (15–28) minutes in the second group (p < .05). Functional success rate at the end of the second postoperative year was 90.2% in the first group and 92.4% in the second (p > .05). Anatomical success rate at the end of second postoperative year was 95.8% in the first group and 98.1% in the second (p > .05). Conclusion DCR operation with physiodispenser shortens the operation duration, reduces excessive bleeding, and has high functional and anatomical success rates.

Practice and Conflict Management in Farmer Managed Irrigation System in Nepal

The main objective of this research is to investigates the practice of farmer managed irrigation system and existing conflicts management practice of farmer managed irrigation system (FMIS), which concerning the construction, operation, maintenance and conflict management of local irrigation systems. The farmers of the study area managed the irrigation system with the adaptation of indigenous knowledge and practices relating to various irrigation management activities such as water allocation, distribution and conflict management. The study is based on structured interview, Focus Group Discussion (FGD) and Key Informant Interview for the data collection. The major battle in FMIS in Nepal that are discussed here are water allocation and distribution, external development, assistance, resource misuse, operation and maintenance, and water tax collection.

Analysis and Modeling of Enterprise Competitive Intelligence Based on Social Media User Comments

AbstractUnder modern information conditions, competitive intelligence has an important strategic role for an enterprise to reduce market, financial and other risks. How to correctly evaluate the value of competitive intelligence and make the right decision for an enterprise directly determines the survival and development of an enterprise. By establishing a co-occurrence relationship between the two, the core themes of corporate microblog communication are discovered. Proceeding from the basic theory of the value of competitive intelligence, it is proposed that due to the connection of business departments within the enterprise system, the transfer value of competitive intelligence within the enterprise system is changed, and a mathematical analysis method is used to establish a value transfer analysis model. The value-added process of enterprise competitive intelligence and the internal and external operational processes of the enterprise are unified, and the internal and external competitive intelligence value-added operation modes of enterprises led by different strategies are studied. This provides a new and widely-referenced operational reference for different companies to effectively formulate and implement their competition and cooperation strategies through internal and external competitive intelligence operations.

The results of Ritleng bicanalicular silicone intubation for congenital and adult partially acquired nasolacrimal duct obstruction.

OBJECTIVE:Our aim was to evaluate the long-term results of Ritleng bicanalicular silicone intubation for congenital and adult partially acquired nasolacrimal duct (NLD) obstruction.METHODS:We evaluated 28 eyes of the 26 patients treated with lacrimal intubation with the Ritleng method retrospectively. Patients were divided into two groups. Patients with congenital NLD obstruction (n: 16) constituted Group 1 and patients with adult partially acquired NLD obstruction (n: 10) constituted Group 2. The Ritleng probe was inserted from the canaliculus into the inferior meatus. Success was defined within two parameters: (1) Intubation of the silicone tube without complications and (2) recovery of the previous signs and symptoms and a normal fluorescein dye test.RESULTS:Mean of the patients’ ages was 2.4±1.6 years in Group 1 and 49±15 years in Group 2. The intubation was successful in all of the patients (100%) in Group 1, meanwhile in Group 2, false passage was observed in 2 patients (20%). Silicone tube was removed through the punctum in outpatient clinic conditions between 2 weeks and 3 months (mean: 2.1 months) in Group 1 and 4–6 months (mean: 5.2 months) in Group 2. Patients in Groups 1 and 2 were followed for 26±18.6–36±25 months, respectively. Previous signs and symptoms were recovered in 75% of the patients in Group 1 and the dye tests of these patients were normal. In Group 2, only two patient’s symptoms were resolved (20%). For the adult patients whose symptoms were not resolved, an external dacryocystorhinostomy operation was performed.CONCLUSION:The Ritleng lacrimal intubation system is an effective procedure for the treatment of congenital NLD obstruction for both short and long term. On the other hand, the effectiveness of the procedure is limited for the adult partially acquired NLD obstruction.

Retracted] Construction and Analysis of Green Investment Risk Evaluation Index System Based on Information Entropy Fuzzy Hierarchical Analysis Model

This paper adopts the information entropy fuzzy hierarchical analysis model to conduct an in‐depth study and analysis of the green investment risk evaluation system and to process and analyze its indicators. The entropy method‐fuzzy hierarchical analysis is used to evaluate the green financial capital operation risk. Firstly, I point out the research trends and shortcomings, define the concepts of fund operation, operation risk, risk evaluation, and green finance, and elaborate the relevant basic theories to lay the theoretical foundation for the later research; secondly, I identify the external and internal fund operation risks by describing the development plan, overall operation, and specific operation plan of green finance; then, according to the existing fund operation risks, I integrate commercial banks’ risk. Then, based on the existing fund operation risks, I integrate the risk types of commercial banks, combine the characteristics of green finance business, design the green finance fund operation risk evaluation index system, initially determine the index weights through hierarchical analysis method, introduce the entropy value method to improve the index weights, and use the fuzzy comprehensive evaluation method to obtain the final evaluation results: in the process of green finance fund operation, internal risk is the most important risk, among which credit risk and financial innovation risk have the most significant impact; external risk is the second most important risk, among which economic risk and political risk are the most important. External risks are the second most important risks, among which economic risks and political risks are more obvious. The risks are judged from single‐factor aspects, and the scoring values are used to determine the higher possibility of schedule risks caused by human factors, and finally, the schedule risk level of the reservoir project is determined to be medium through a comprehensive evaluation. The reasonableness of the calculation results shows that the entropy theory and the fuzzy comprehensive evaluation method are still applicable to the assessment of green investment risks.

Microstructure and Pressure-Driven Electrodeposition Stability in Solid-State Batteries

Interfacial deposition stability at the Li-metal-solid electrolyte interface in all solid-state batteries is governed by the stress-transport-electrochemistry coupling in conjunction with the polycrystalline/amorphous solid electrolyte architecture. In this work, we delineate the optimal solid electrolyte microstructure comprising grains, grain boundaries, and voids possessing desirable ionic conductivity and elastic modulus for superior transport and strength. An analytical formalism is provided to discern the impact of external “stack” pressure-induced mechanical stress on electrodeposition stability; the stress magnitudes obtained are in the megapascal range, considerably diminishing the stress-kinetics effects. For experimental stack pressures ranging up to 10 MPa, the impact of stress on reaction kinetics is negligibly small, and electrolyte transport overpotentials dictate electrodeposition stability. High current density operation with stable deposition can be ensured with ample external pressure, high temperature, and low surface roughness operation for a low shear modulus ratio of the solid electrolyte to Li-metal. Solid electrolyte architecture is screened via virtual generation and characterization Large grain size, low void size, and porosity provide favorable conduction and stiffness Stack pressure <10 MPa has negligible impact on stress-kinetics coupling High operating pressure, temperature, and low roughness can aid stable deposition Lithium electrodeposition is dependent on solid electrolyte microstructure, stack pressure, and operating temperature. Verma et al. suggest a method to delineate the architecture and operating conditions that lead to stable deposition.

Continuous model predictive control of interleaved boost converter with current compensation

An interleaved DC–DC boost converter is widely used in DC power systems such as fuel cell systems or other systems requiring high-power quality for increasing and stabilising the output voltage. The performance of the converter can be affected by the control strategy. In this study, a robustness continuous control set model predictive control (CCS-MPC) for an interleaved DC–DC boost converter is proposed to achieve optimised transient dynamics and steady performance. To deal with unknown load variation and systems uncertainties, an extended Kalman observer is designed to estimate the lumped disturbance, including the load variation and unmodelled part. Based on the disturbance estimation, a dynamic current reference with the disturbance and the integrated voltage error is formulated for the optimal voltage tracking. Also, a prediction-accuracy-enhanced CCS-MPC for a wide range of operation points and multi-parameter disturbance is obtained. The proposed approach could stabilise the output voltage with good robustness under external disturbance and operation point change. Compared with other existing controllers, i.e. a proportional–integral controller, a sliding mode controller, and a finite control set model predictive controller, both the steady and transient performances are validated by a simulation and experimental test bench.

Inertial microfluidics: Recent advances.

Inertial microfluidics has attracted significant attentions in last decade due to its superior advantages of high throughput, label- and external field-free operation, simplicity, and low cost. A wide variety of channel geometry designs were demonstrated for focusing, concentrating, isolating, or separating of various bioparticles such as blood components, circulating tumor cells, bacteria, and microalgae. In this review, we first briefly introduce the physics of inertial migration and Dean flow for allowing the readers with diverse backgrounds to have a better understanding of the fundamental mechanisms of inertial microfluidics. Then, we present a comprehensive review of the recent advances and applications of inertial microfluidic devices according to different channel geometries ranging from straight channels, curved channels to contraction-expansion-array channels. Finally, the challenges and future perspective of inertial microfluidics are discussed. Owing to its superior benefit for particle manipulation, the inertial microfluidics will play a more important role in biology and medicine applications.

Parallel Subdomain-Level DGTD Method With Automatic Load Balancing Scheme With Tetrahedral and Hexahedral Elements

In this article, an automatic load balancing method for the parallel subdomain-level discontinuous Galerkin time-domain (DGTD) method has been proposed based on the message passing interface (MPI) library. First, a diagram that exhibits the relationship between the computation load (CPU time) and the DoFs has been extracted from numerical experiments for hexahedral and tetrahedral meshes, respectively. Then, an automatic iteration load balancing scheme has been employed to optimize the positions of the interfaces in order to minimize the CPU time differences between subdomains with the help of the diagram obtained in the first step. This scheme comes with a one-click solution using a greedy algorithm after an initial division of the original model, which is the only step that requires an external operation. In addition, the whole load balancing scheme is only involved in the preprocessing part of the code without modifying the system matrices iteratively. Consequently, the load balance can be relatively easily and efficiently implemented, which can significantly expedite the simulation of the large/multiscale models. The effectiveness of this load balancing strategy has been demonstrated via numerical cases.

Are business relationships institutions?

The question is simple; the answer could be quite complicated. Inter-organisational marketing researchers define business relationships as interactive exchanges between two organisations. Does this mean anything for institutional economists? A business relationship is created by weaving actor bonds, resource ties and activity links. Business relationships exist and change through time. The establishment, development, maintenance, as well as termination of a business relationship all require investments from the participating parties. A business relationship does not exist in an isolated manner, but other market and non-market actors can equally influence it. In reality, numerous other relationships and actors affect business relationships. As a result, these actors indirectly influence business relationships through the change in behaviour of one of the parties within the business relationship. These directly and indirectly affected relationships create a business network. For an organisation business relationships have different functions. External resources neededfor operation and value creation are fed by them. Value creation for the customer and value sharing with the customer take place in business relationships. They are forms of an organisation’s interdependence. A business relationship is a special form of governance of the partners’ mutual efforts. A business relationship has its own value for each organisation. Each organisation has several business relationships, each with different value. In business markets,where buyers are always organisations, the business relationship portfolio is the market itself. Inter-organisational marketing researchers use very different theoretical foundations to study business relationships. Modern contract law based research distinguishes about a dozen norms of behaviour in business relationships. Institutional economic-rooted studies argue that we should use the plural-forms approach (price, authority and trust must be employed together) to explain these very complex phenomena. Research using communication theory concluded that multiple periods of business negotiations were required to develop even primitive norms. The paper concludes with some elements of a possible answer to the title question.

Management Innovations Research of the Logistics Enterprises Based on the Big Data Environment

In the operation of logistics enterprises, both internal management and external operation will produce a lot of data. It can be effectively used as the information assets of enterprises and the guidance for enterprise management optimization, cost control, efficiency enhancement, risk identification and avoidance, which is of great significance to the future of enterprises. Big data with its advantages is different from traditional data processing. It can be combined with management innovation of logistics enterprises to effectively optimize the allocation of logistics enterprises resources. The paper mainly explores the direction of the combination of big data and logistics enterprise management and innovative measures.

Computer Programmes for Determining the Probability and Consequences of Major Accidents

The article presents an overview of the most popular available computer programmes in Poland used to support the implementation of particular stages of the process of risk analysis and assessment for lower or upper tier establishments. Particular attention was focused on the advantages and disadvantages of particular programmes, taking into account their functionality, availability, ease of use, as well as the reliability and validation of the results obtained. The appropriate selection of a program to determine the hazard zones, consequences, frequencies, and risk indicators of accident scenarios allows designing adequate safety and protection measures to be adopted in the event of occurrence of such undesired events. It also facilitates the preparation of risk maps as well as internal and external operation and emergency plans.

Evaluation of an advanced slung load control system for piloted cargo operations

Helicopter operations with externally slung loads are highly demanding for the flight crew. As the pilot does not have a direct view of the load, assistance is required from an additional crew member to achieve operational requirements (e.g., for load handling to achieve precise load positioning). An automatic load stabilization and positioning system for cargo operations has been designed with the aim to reduce pilot workload, damp load pendulum motion and to improve the load positioning performance. This system uses the concept of load-motion feedback to the rotor control. To avoid degradation of Handling Qualities (HQs), as found in previous investigations, a function has been developed that monitors pilot control inputs. Dependent on the amplitude and duration of pilot control stick deflection, the feedback signal for slung load damping is blended between two different gain sets. One set provides improved HQs during piloted control and one set provides good load damping when the pilot is passive. A further novel aspect is the evaluation of an automatic load control system using a Translational Rate Command as a method of helicopter control. A piloted simulation study has been conducted using this advanced load control system with automatic load stabilization and positioning. Three test pilots evaluated the system in different control law configurations using a Mission Task Element simulating an external load cargo operation. HQs and pilot workload were evaluated using the Cooper-Harper Rating Scale and NASA Task Load Index, respectively. The results of the study show that improved HQs and reduced pilot workload in combination with improved task performance can be achieved with the advanced slung load control system.

Visible-Light-Induced Decarboxylative Cyclization of 2-Alkenylarylisocyanides with α-Oxocarboxylic Acids: Access to 2-Acylindoles.

An efficient and practical protocol for visible-light-induced decarboxylative cyclization of 2-alkenylarylisocyanides with α-oxocarboxylic acids has been developed, which afforded a broad range of 2-acylindoles in moderate to good yields. The reaction proceeds through a cascade of acyl radical addition/cyclization reactions under irradiation of an Ir3+ photoredox catalyst without external oxidants and features simple operation, scalability, a broad substrate scope, and good functional group tolerance.

Operation strategy of a solar-gas fired single/double effect absorption chiller for space cooling in Indonesia

A solar-gas fired absorption cooling system has been installed and tested in a real environment at the University of Indonesia, Depok, Indonesia. The cooling system provides chilled water to the building of the Mechanical Research Center of the university. This system has a unique single/double-effect water/Lithium Bromide absorption chiller with a nominal cooling capacity of 239 kW. In addition, the system consists of evacuated tube solar collectors (~181 m2 total aperture area) and fan coil units installed in the building. The absorption chiller is driven by (i) hot water (75 – 90 °C) produced by the solar collectors which supply heat to the single-effect generator and (ii) by a direct gas-fired burner at the double-effect high-temperature generator when it is needed. The driving heat supply from the gas-burner is 113.2 kW and 93.3 kW (at 90 °C) from the solar collector field. This study focuses on the control strategy of the solar-gas fired absorption chiller system based on operational data obtained from the field test carried out in an Asian tropical climate, particularly Indonesia. The proposed and implemented control strategy consists of the control of both external and internal operation variables. The external control strategy includes the control of three water flow loops (hot water, cooling water, and chilled water) that are controlled according to the cooling load of the building and weather conditions (i.e., solar irradiation and ambient temperature). The internal operation variable (total solution flow rate) and gas flow rate are adjusted according to the required cooling capacity. The field tests of thermal and electrical COP are around 0.9–1.1 and 4.5–5.5, respectively. The field test results demonstrate the feasibility of the implemented control strategy for the optimum and safe operation of the system in an Indonesian climate, with the possibility of adapting to other similar Asian tropical climates.

Digital twin-enabled anomaly detection for built asset monitoring in operation and maintenance

Effective asset management plays a significant role in delivering the functionality and serviceability of buildings. However, there is a lack of efficient strategies and comprehensive approaches for managing assets and their associated data that can help to monitor, detect, record, and communicate operation and maintenance (O&M) issues. With the importance of Digital Twin (DT) concepts being proven in the architecture, engineering, construction and facility management (AEC/FM) sectors, a DT-enabled anomaly detection system for asset monitoring and its data integration method based on extended industry foundation classes (IFC) in daily O&M management are provided in this study. This paper presents a novel IFC-based data structure, using which a set of monitoring data that carries diagnostic information on the operational condition of assets is extracted from building DTs. Considering that assets run under changing loads determined by human demands, a Bayesian change point detection methodology that handles the contextual features of operational data is adopted to identify and filter contextual anomalies through cross-referencing with external operation information. Using the centrifugal pumps in the heating, ventilation and air-cooling (HVAC) system as a case study, the results indicate and prove that the novel DT-based anomaly detection process flow realizes a continuous anomaly detection of pumps, which contributes to efficient and automated asset monitoring in O&M.

Detection of ESD-Induced Soft Failures by Analyzing Linux Kernel Function Calls

Electrostatic discharge (ESD) into a functioning system can cause temporary upsets - soft failures. Subtle soft failures can reduce the reliability of system and cannot be detected by conventional methods based on external equipment or operation system (OS) log. This paper presents a proof of concept for a novel methodology for detection of ESD-induced soft failures through analyzing kernel function trace recordings of the operation system. The method is based on recording Linux kernel function calls during normal operation and after ESD stress injection. The recorded information is visualized in forms of graphical maps of function execution and system call distribution for each process to highlight ESD induced changes. The experimental data shows that soft failures manifest themselves as changes in the function maps and the call distribution within the observed processes. This novel method is capable of detecting subtle system upsets which are not observable for the user through standard I/O or attached equipment.

RESEARCH OF QUANTITATIVE CHARACTERISTICS OF GRAIN RAILWAY ON GRAIN TERMINAL

An important component of the production and export of grain is the system of transportation of grain from its producers to grain reloading terminals. Among the means of transportation of grain the leading place is occupied by the railway, which is able to provide uninterrupted multi-tonnage transportation of grain from producers to the places of its accumulation and shipment to sea vessels. However, there are some problems in the internal and external operation of grain terminals, which has necessitated these studies. The purpose of the study was to investigate the quantitative and qualitative characteristics of the flow of grain from the railway to the grain terminal to improve its efficiency. The object of the study was the technological process of receiving grain from the railway at the grain terminal; The subject of the research was grain crops, as well as data on daily revenues of grain by railway transport at the grain reloading terminal of LLC «Ukrelivatorprom» for three calendar years — from January 1, 2012 to December 31, 2014. The studies were conducted on the basis of the processing of the data of the invoice logs for each year of the research, which summed up the amount of daily transported grain (net). Further processing of the obtained was performed by the combined graphoanalytical method, for which on the basis of tables for each investigated year the corresponding histograms were constructed and the necessary indicators were determined. It was found that maize had the highest volumes of grain coming from the railways in 2012–2014, followed by wheat in 2012 and rapeseed in 2013–2014. Barley was the third, except for 2013, in which its volumes were the smallest among the main crops that came to LLC «Ukrelevatoprom» in the years studied. It is shown that the major share was occupied by cereals (67.1… 78.1%), followed by oilseeds (15.1…26.7%), and the smallest was occupied by legumes (2.77…6.8%). The duration of the annual grain intake periods, which amounted to 315, 331 and 333 days, respectively, was determined for 2012–2014. Annual, daily average and maximum grain yields were determined, as well as daily and annual irregularity coefficients of grain supply. The actual coefficients of the daily irregularity of the grain input from the railway in the period 2012-2014 were respectively Kdaily = 1.62; 1.86; 1.79, and monthly irregularities respectively K mont. = 1.31; 1,40; 1.35. According to the standards such coefficients have values Kdaily = 2.5 and Kmont. = 2.0, which allows to use them for design and verification calculations of grain terminal equipment in technological processes of grain acceptance from railway transport.

Optimization performance management with FCAPS and ITILv3: opportunities and obstacles

&lt;p&gt;With the need for rapidly growing network services each year; the factors of reliability, availability and quality become extremely critical for organizations, groups, institutions and governments to have in the network services implementation. In this case, several rural governments requires the improvement of its network performance management in establishing their internal and external operation to align with the grand design by the central government in improving citizen’s satisfaction through public service. Testing was done using scenarios for output analysis and packet loss as parameters. The results of the proposed topology obtained a productivity of 541.43 Kbps and a packet loss of 0.07%. While the current topology gets a rate of 421.28 Kbps and packet loss of 0.22%. It can be concluded that the proposed topology is still better than the current topology. The optimization of performance management is based on the FCAPS method which emphasize in the performance monitoring and data analysis with the support of ITILv3 that contains documentation and policy guidance to conduct quality performance management. In addition, performance management activities will occur with processes in the design of ITIL services and existing conditions.&lt;em&gt;&lt;/em&gt;&lt;/p&gt;

Electrochemical polarization analysis for optimization of external operation parameters in zinc fuel cells.

Zinc–air flow fuel cells utilizing zinc particles as fuel possess the potential to evolve as efficient distributed grid generators. In this research study, electrochemical impedance analysis was employed to determine the optimum design and operational parameters for the feasible maneuver and enhanced energy generation from zinc fuel cells. Polarization resistance (Rp), ohmic resistance (Rs), and mass transfer resistance (Rm) were used as the indicators for determination of the optimum parameters of fuel cell performance. Experimental conditions optimized from previous studies like potassium hydroxide electrolyte with temperature of 25 °C and concentration of 40 wt% zinc powder quantity of 20 g, electrode reaction surface area of 48 cm2 were followed in the fuel cells used in the present study. Parameters like collector plate material, air flow velocity and cell operating temperature were augmented and finally were all implemented in the fuel cell and operated. Plain nickel or nickel-plated copper were both advantageous as collector plate materials whereas an air flow velocity ranging from 1–3 m s−1 and a cell operating temperature of 25 °C to 45 °C were beneficial for the stability and performance of the zinc fuel cells. Finally, based on the optimized parameters obtained from the above experiments, performance tests of zinc fuel cells were investigated. The maximum power produced was 16.5 W, along with a corresponding voltage of 0.8 V, maximum current density of 430 mA cm−2 and peak power density of 364.6 mW cm−2. Thus it can be concluded that the fuel cells designed and operated in this study were capable for feasible and efficient future applications.