Effects of aggregating forests, establishing forest road networks, and mechanization on operational efficiency and costs in a mountainous region in Japan

We investigated forest road networks and forestry operations before and after mechanization on aggregated forestry operation sites. We developed equations to estimate densities of road networks with average slope angles, operational efficiency of bunching operations with road network density, and average forwarding distances with operation site areas. Subsequently, we analyzed the effects of aggregating forests, establishing forest road networks, and mechanization on operational efficiency and costs. Six ha proved to be an appropriate operation site area with minimum operation expenses. The operation site areas of the forest owners＇ cooperative in this region aggregated approximately 6 ha and the cooperative conducted forestry operations on aggregated sites. Therefore, 6 ha would be an appropriate operation site area in this region. Regarding road network density, higher-density road networks increased operational expenses due to the higher direct operational expenses of strip road establishment. Therefore, road network density should be reduced to approximately 200 m.

An Analysis of Operational Efficiency of Agricultural Insurance Agency:Based on Three-Stage DEA Model

From the perspective of agricultural insurance agency,this paper focuses on the study of operational efficiency of agricultural insurance agency,and analyzes the operational efficiency of agricultural insurance agency and its influencing factors,in order to improve the operational efficiency of agricultural insurance agency,better supply agricultural insurance and achieve the policy effect of agricultural insurance.The results of this paper are as follows:( i) Either comprehensive operational efficiency or scale efficiency of Chinese-funded agency is higher than that of foreign-funded agency,but its pure technical efficiency is lower than that of foreign-funded agency,indicating that the managerial decision ability of Chinese-funded agency is weaker than that of foreign-funded agency,and needs to be improved;( ii) The operational efficiency of professional agricultural insurance agency is higher than that of comprehensive agricultural insurance agency,and the agricultural insurance agency is greatly affected by environmental factors;( iii) The operating time of agricultural insurance agency is proportional to its operational efficiency;( iv) The quality of employees is positively correlated with the capital and cost input difference,but negatively correlated with the difference in the number of employees. Therefore,it is necessary to pay attention to the improvement of employees' working efficiency while laying emphasis on employees' quality.

The Correlation of Hospital Operational Efficiency and Average Length of Stay in China: A Study Based on Provincial Level Data

Objective: To measure the hospital operation efficiency, study the correlation between average length of stay and hospital operation efficiency, analyze the importance of shortening average length of stay to the improvement of the hospital operation efficiency and put forward relevant policy suggestion. Methods: Based on China provincial panel data from 2003 to 2012, the hospital operation efficiencies are calculated using Super Efficiency Data Envelopment Analysis model, and the correlation between average length of stay and hospital operation efficiency is tested using Spearman rank correlation coefficient test. Results: From 2003 to 2012, the average of national hospital operation efficiency was increasing slowly and the hospital operations were inefficient in most of the areas. The national hospital operation efficiency is negatively correlated to the average length of stay. Conclusion: Measures should be taken to set average length of stay in a scientific and reasonable way, improve social and economic benefits based on the improvement of efficiency.

Analysis on Operational Safety and Efficiency of FAO System in Urban Rail Transit

This paper discusses two urgent problems that need to be solved in fully automatic operation(FAO)for urban rail transit.The first is the analysis of safety in FAO,while another is the analysis of efficiency in FAO.Firstly,this paper establishes an operational safety evaluation index system from the perspective of operation for the unique or typical risk sources of the FAO system,and uses the analytic hierarchy process(AHP)to evaluate the indicators,analyzes various factors that affect the safe operation of FAO,and provides safety management recommendations for FAO lines operation to maintain the FAO system specifically.Secondly,taking the Yanfang Line as an example,this paper uses OpenTrack software to analyze the efficiency of FAO operation,and conducts simulation calculations for key links such as the mainline tracking interval,train entry and exit,and return limit interval.The fault impact surface of the FAO trains is simulated and discussed to verify whether FAO can meet the long-term operation requirements of Yanfang Line.Finally,this paper compares the simulation data of FAO on the Yanfang Line with manual operation(MO)to verify the advantages of FAO and guide the engineering construction of subsequent fully automated driving lines.

Holistic Approach to Safety and Operational Stability: Analyzing VVER-1200 Reactor Dynamics in SGTR and AC Power Loss

VVER-1200 (Water-Water Energetic Reactor) represents a significant advancement in nuclear power generation, emphasizing the continuous analysis and enhancement of safety systems for reliable operation. The proposed study focuses on simulating combined scenarios involving steam generator tube rupture (SGTR) and AC power loss using core algorithms and models within personal computer transient analyzer (PCTRAN). Reactor kinetic equations, thermal-hydraulic balance, and safety system models are discussed to elucidate their role in simulating SGTR and AC power loss. Safety criteria, boundaries and initial conditions are outlined to provide a comprehensive understanding of the simulation framework. The analysis delves into dynamic behavior of VVER-1200, placing emphasis on thermal-hydraulic implications, essential reactor parameters, and radiation monitoring to facilitate impact evaluation. Continuous monitoring and maintenance of safety systems are underscored to ensure stable core cooling, particularly during proposed transient conditions. Through meticulous analysis and comparison with established benchmarks, this study contributes to bolstering the safety and reliability of VVER-1200 reactors by identifying vulnerabilities, assessing mitigation strategies, and refining emergency response protocols. Practical implications of this study offer a crucial understanding of reactor behavior, safety system performance, and emergency response strategies, thereby improving safety, optimizing operational practices, and reducing risks in nuclear reactor accidents.

基于Cross-efficiency DEA的中间站运营绩效分析

根据传统DEA存在的局限性,在有关文献研究的基础上,提出了基于Cross-efficiency DEA模型的中间站绩效分析方法,在调查收集影响中间站运营绩效基础数据的基础上,利用灰色关联分析法提取了评价指标体系,采用Cross-efficiency DEA模型对中间站运营绩效进行了分析、评价和测算,并运用MATLAB软件编程进行了求解,获得了各中间站源配置效率的排序,在对非DEA有效的决策单元进行投影分析的基础上,识别出影响决策单元运营绩效的关键因素,为改进非DEA有效决策单元提供了一个可行方案。最后利用实例验证了该模型的有效性、科学性,分析结果表明:Cross-efficiency DEA模型基本能够反映决策单元运行效率的现实状况。

Developing and Applying a Ship Operation Energy Efficiency Evaluation Index Using SEEMP: a Case Study of South Korea

The CO2 emission reduction policy of the International Maritime Organization(IMO)recommends that the operation of ships,managed by maritime transport companies,should be energy-efficient.An evaluation method that can determine how successfully a ship implements the energy efficiency plan is proposed in this study.To develop this method,the measures required for energy-efficient ship operations according to the Ship Energy Efficiency Management Plan(SEEMP)operational guidelines were selected.The weights of the selected measures,which indicate how they contribute to the energy-efficient operation of a ship,were derived using a survey based on the analytic hierarchy process(AHP)method.Consequently,using these measures and their weights,a new evaluation method was proposed.This evaluation method was applied to shipping companies in South Korea,and their ship operation energy efficiency indices were derived and compared.This evaluation method will be useful to the government and shipping companies in assessing the energy efficiency of ship operations.

Prediction of face advance rate and determination of the operation efficiency in retreat longwall mining panel using rock engineering system

A new approach for prediction of face advance rete (FAR) prior to mining operation and determination of the operation efficiency after mining operation in retreat longwall mining panel is presented based upon the concepts of rock engineering system (RES). For this purpose, six longwall panels considered in Parvadeh-I coal mine. Seven major effective parameters on FAR was selected including coal mine roof rating, gas propagation, safety factor of longwall face, ratio of joint spacing to cutting depth at longwall face, longwall face inclination, panel width, floor rock mass rating. To performance evaluation of the presented model, the relationship between the average vulnerability indexes of advance operation with FAR was determined in considered panels with coefficient of determination (R2) equal to 0.884 that indicate relatively acceptable correlation and compatibility. Investigations of the research indicated that it is possible to determine the actual operation efficiency under fair conditions by a RES-based model. The inevitable reduction of FAR for each longwall panel was determined by presented model that the difference amount between the maximum possible practical face advance rate (FARmpp) and recorded actual face advance rate (FARa) indicate the operation efficiency. Applied approach in this paper can be used to prediction of FAR in retreat longwall mining panel for same conditions that can have many benefits, including better and more accurate planning for the sales market and mine operation. Also, presented method in this paper can be applied as a useful tool to determination of actual operation efficiency for other sections and extraction methods in coal mines.

Operational Options for Green Ships

Environmental issues and rising fuel prices necessitate better energy-etlicwncy in all sectors, The shipping industry is one of the major stakeholders, responsible for 3% of global CO2 emissions, 14%-15% of global NOx emissions, and 16% of global SOx emissions. In addition, continuously rising fuel prices are also an incentive to focus on new ways for better energy-effectiveness. The green ship concept requires exploring and implementing technology on ships to increase energy-efficiency and reduce emissions. Ship operation is an important topic with large potential to increase cost-and-energy-effectiveness. This paper provided a comprehensive review of basic concepts, principles, and potential of operational options for green ships. The key challenges pertaining to ship crew i.e. academic qualifications prior to induction, in-service training and motivation were discussed. The author also deliberated on remedies to these challenges.

Operation Efficiency Optimisation Modelling and Application of Model Predictive Control

The efficiency of any energy system can be charaterised by the relevant efficiency components in terms of performance, operation, equipment and technology(POET). The overall energy efficiency of the system can be optimised by studying the POET energy efficiency components. For an existing energy system, the improvement of operation efficiency will usually be a quick win for energy efficiency. Therefore, operation efficiency improvement will be the main purpose of this paper. General procedures to establish operation efficiency optimisation models are presented. Model predictive control, a popular technique in modern control theory, is applied to solve the obtained energy models. From the case studies in water pumping systems, model predictive control will have a prosperous application in more energy efficiency problems.

Operational efficiencies and costs of an arm roll forwarder: A case study at Nasu in Tochigi Prefecture, Japan

We investigated a developed arm roll forwarder at Nasu in Tochigi Prefecture, Japan. An arm roll forwarder can only load a steel container that has been fully loaded with logs beforehand, and can later unload such a container. Such a forwarder can shorten the loading and untoading times and improve operational efficiency. We examined two operation systems with an arm roll forwarder and a forwarder. In the first system the loading was done with a grapple-loader. In the second system the loading was done with a processor. The loading times of an arm roll forwarder were significantly tess than those of a forwarder. Because the optimal cycle times （excluding the waiting times for an arm roll for- warder） were significantly reduced, the costs of using an arm roll for- warder are lower, although the loading capacity was small and the hourly operation cost was high. The maximum operational efficiencies varied depending on forwarding distances. The second operation system with an arm roll forwarder exhibited the best operational efficiency within a 1,580-m forwarding distance, and beyond that distance it exhibited the highest operational efficiency when a forwarder was used. Similarly, the cost of operation of the system with an arm roll forwarder was the lowest within a 1,130-m forwarding distance, and beyond that distance the cost was the lowest when using the forwarder. Therefore, the arm roll for- warder is effective within a certain forwarding distance.

Operation Efficiency and Influencing Factors of Listed Companies of Swine Industry:Empirical Analysis Based on Data of 16 Listed Companies in 2010-2014

Listed companies of the swine industry,as an important form of agricultural industrialized operation,are typical representatives of large-scale production and the level of their operation efficiency exerts a direct influence on the healthy development of the swine industry.Using the DEA-based Malmquist method,this paper made a static and dynamic evaluation of the operation efficiency of 16 listed companies in China's swine industry in 2010-2014. It obtained following results:( i) The overall efficiency of listed companies of China's swine industry remained at high level and the development trend was excellent.( ii) Different types of enterprises had difference in the overall efficiency,pure technical efficiency and scale efficiency. In general,pig feed processing companies had the best performance,followed by slaughtering and deep processing companies,and swine breeding companies were the worst.( iii) The total factor productivity characterized by the Malmquist index declined year by year in 2010-2013 and was improved in 2014,mainly due to technological progress.( iv) The total asset turnover ratio,equity concentration,and R & D management level had a significantly positive impact on the operation efficiency of listed companies in the swine industry,while the human capital had a significantly negative impact.

Sensitivity and effect of key operational parameters on performance of a dual-cylinder free-piston engine generator

The free-piston engine generator(FPEG)is regarded as the next generation of energy conversion system which may replace traditional engines in the future.The effect of key operational parameters like excess air ratio of input mixture and ignition position on the engine performance of a dual-cylinder FPEG was investigated,and their sensitivity was analyzed in this paper.The operating compression ratio of the system is susceptible to changes in excess air ratio and ignition position.At the same time,it decreases from 15.8 to 6.6 when excess air ratio increases from 0.85 to 1.15,but it increases from 6.1 to 13.3 as ignition position increases from 15 mm to 20 mm.The operating frequency and indicated power are more sensitive to changes in excess air ratio than ignition position.But it is the opposite for the indicated thermal efficiency and friction loss.Excess air ratio and ignition position have a quite similar influence on heat transfer.Therefore,from the perspective of system operation and performance,it is preferable to keep excess air coefficient slightly below 1.0.In contrast,when selecting ignition position,it is of great importance to comprehensively consider the risk of structural damage caused by the increase in the compression ratio and in-cylinder gas pressure.

The Operation Efficiency Evaluation for Listed Companies of China Aviation Industry Based on DEA and Malmquist Index

The data envelopment analysis （DEA） is used to evaluate operation efficiency of 17 listed companies in China aviation industry from 2006 to 2011, and make longitudinal analysis for the operation efficiency. In addition, the reason of changing efficiency is dynamically evaluated by Malmquist productivity index. The empirical results show that average operation efficiency of 17 listed companies in China aviation industry is less than 1, which means that the operation activities of aviation industry exist diseconomies characteristic, technological progress efficiency is a major influenced factor

Influence of Missile Fusillade Engagement Mode on Operation Efficiency

Shoot efficiency is one of the most important evaluation indexes of the operation efficiency of weapon system.In this paper,based on definitions of the probability and the expected number of missed attacking missiles,the expected numbers of anti-missiles and attacking missiles hit by single anti-missile,fusillade mechanism of multi-missile is analyzed systematically.The weapon operation efficiency in various engagement patterns is also studied.The results show that double missiles fusillade is the most feasible manner for increasing the weapon operation efficiency.

Effects of Low Temperature on Operation Efficiencyof Tree-Felling by Chainsaw in North China

Comparison method and vidco-tape recorders were used in case study for recording thc operation performances of two group operators. The time span was 7 months, from September 10 March. The performance of operations in September was taken as references. The results of test survey and data analysis showed that the tree-felling operation efficiency was influenced by cold weather, properly decreased 18.5% in average.

Efficient Slew-Rate Enhanced Operational Transconductance Amplifier

Today, along with the prevalent use of portable equipment, wireless, and other battery powered systems, the demand for amplifiers with a high gain-bandwidth product（GBW）, slew rate（SR）, and at the same time very low static power dissipation is growing. In this work, an operational transconductance amplifier（OTA） with an enhanced SR is proposed. By inserting a sensing resistor in the input port of the current mirror in the OTA, the voltage drop across the resistor is converted into an output current containing a term in proportion to the square of the voltage, and then the SR of the proposed OTA is significantly enhanced and the current dissipation can be reduced. The proposed OTA is designed and simulated with a 0.5μm complementary metal oxide semiconductor（CMOS） process. The simulation results show that the SR is 4.54V/μs, increased by 8.25 times than that of the conventional design, while the current dissipation is only 87.3%.

Dual-radiation-chamber coordinated overall energy efficiency scheduling solution for ethylene cracking process regarding multi-parameter setting and multi-flow allocation

Ethylene cracking process is the core production process in ethylene industry,and is paid more attention to reduce high energy consumption.Because of the interdependent relationships between multi-flow allocation and multi-parameter setting in cracking process,it is difficult to find the overall energy efficiency scheduling for the purpose of saving energy.The traditional scheduling solutions with optimal economic benefit are not applicable for energy efficiency scheduling issue due to the neglecting of recycle and lost energy,as well as critical operation parameters as coil outlet pressure(COP)and dilution ratio.In addition,the scheduling solutions mostly regard each cracking furnace as an elementary unit,regardless of the coordinated operation of internal dual radiation chambers(DRC).Therefore,to improve energy utilization and production operation,a novel energy efficiency scheduling solution for ethylene cracking process is proposed in this paper.Specifically,steam heat recycle and exhaust heat loss are considered in cracking process based on 6 types of extreme learning machine(ELM)based cracking models incorporating DRC operation and three operation parameters as coil outlet temperature(COT),COP,and dilution ratio according to semi-mechanism analysis.Then to provide long-term decision-making basis for energy efficiency scheduling,overall energy efficiency indexes,including overall output per unit net energy input(OONE),output-input ratio per unit net energy input(ORNE),exhaust gas heat loss ratio(EGHL),are designed based on input-output analysis in terms of material and energy flows.Finally,a multiobjective evolutionary algorithm based on decomposition(MOEA/D)is employed to solve the formulated multi-objective mixed-integer nonlinear programming(MOMINLP)model.The validities of the proposed scheduling solution are illustrated through a case study.The scheduling results demonstrate that an optimal balance between multi-flow allocation,multi-parameter setting,and DRC coordinated operation is reached,which achieves 3.37%and 2.63%decreases in net energy input for same product output and conversion ratio,as well as the 1.56%decrease in energy loss ratio.

Study of Efficiency of Agricultural Listed Companies Based on DEA Model

As leading enterprises supporting the agricultural development,agricultural listed companies play a great role,thus the study on their operating efficiency will have a strong demonstration effect. Using the data envelopment analysis( DEA) model,the operating efficiency of 20 agricultural listed companies was compared and analyzed. The results indicated that the overall efficiency of the agricultural listed companies is low. In agricultural listed companies with low or moderate overall efficiency,some agricultural companies are affected by the pure technical efficiency or scale efficiency,while other companies are affected by both factors,and accompanied with the increasing or decreasing efficiency along with the scale. Through in-depth analysis,it concluded that nine companies affected by pure technical efficiency have different degree of input redundancy or output deficiency. On this basis,it came up with pertinent recommendations for improvement.

Pediatric endoscopy across multiple clinical settings:Efficiency and adverse events

BACKGROUND Endoscopic procedures are becoming increasingly important for the diagnosis and treatment of gastrointestinal disorders during childhood,and have evolved from a more infrequent inpatient procedure in the operating room to a routine outpatient procedure conducted in multiple care settings.Demand for these procedures is rapidly increasing and thus there is a need to perform them in an efficient manner.However,there are little data comparing the efficiency of pediatric endoscopic procedures in diverse clinical environments.We hypothesized that there are significant differences in efficiency between settings.AIM To compare the efficiency and examine adverse effects of pediatric endoscopic procedures across three clinical settings.METHODS A retrospective chart review was conducted on 1623 cases of esophagogastroduodenoscopy(EGD)or combined EGD and colonoscopy performed between January 1,2014 and May 31,2018 by 6 experienced pediatric gastroenterologists in three different clinical settings,including a tertiary care hospital operating room,community hospital operating room,and free-standing pediatric ambulatory endoscopy center at a community hospital.The following strict guidelines were used to schedule patients at all three locations:age greater than 6 mo;American Society of Anesthesiologists class 1 or 2;normal craniofacial anatomy;no anticipated therapeutic intervention(e.g.,foreign body retrieval,stricture dilation);and,no planned or anticipated hospitalization post-procedure.Data on demographics,times,admission rates,and adverse events were collected.Endoscopist time(elapsed time from the endoscopist entering the operating room or endoscopy suite to the next patient entering)and patient time(elapsed time from patient registration to that patient exiting the operating room or endoscopy suite)were calculated to assess efficiency.RESULTS In total,58%of the cases were performed in the tertiary care operating room.The median age of patients was 12 years and the male-to-female ratio was nearly equal across all locations.Endoscopist time at the tertiary care operating room was 12 min longer compared to the community operating room(63.3±21.5 min vs 51.4±18.9 min,P<0.001)and 7 min longer compared to the endoscopy center(vs 56.6±19.3 min,P<0.001).Patient time at the tertiary care operating room was 11 min longer compared to the community operating room(133.2±39.9 min vs 122.3±39.5 min,P<0.001)and 9 min longer compared to the endoscopy center(vs 124.9±37.9 min;P<0.001).When comparing endoscopist and patient times for EGD and EGD/colonoscopies among the three locations,endoscopist,and patient times were again shorter in the community hospital and endoscopy center compared to the tertiary care operating room.Adverse events from procedures occurred in 0.1%(n=2)of cases performed in the tertiary care operating room,with 2.2%(n=35)of cases from all locations having required an unplanned admission after the endoscopy for management of a primary GI disorder.CONCLUSION Pediatric endoscopic procedures can be conducted more efficiently in select patients in a community operating room and endoscopy center compared to a tertiary care operating room.