scholarly journals Comparing Hot and Cold Loading in an Integrated Biomass Recovery Operation

Forests ◽  
2020 ◽  
Vol 11 (4) ◽  
pp. 385
Author(s):  
Anil Raj Kizha ◽  
Han-Sup Han ◽  
Nathaniel Anderson ◽  
Anil Koirala ◽  
Libin T. Louis
Keyword(s):  
Forest Harvesting ◽  
Primary Objective ◽  
Operating Conditions ◽  
Sampling Techniques ◽  
Loading Capacity ◽  
Work Sampling ◽  
Operational Characteristics ◽  
Truck Loading ◽  
Biomass Components ◽  
The Cost

The balance of production activities at the landing is pivotal to the success of any forest harvesting operation and has a direct impact on the cost and efficiency of the enterprise. The primary objective of this study was to understand the operational characteristics of the loader in a hot operation (handling both sawlog and biomass components concurrently) and cold operation (handling biomass and sawlogs separately) for harvesting sawlogs and biomass. Systematic work sampling techniques were employed to obtain “snapshots” of the loader activities for a cable logging operation, including the interaction of the loader with other operational phases and delay time for both hot and cold configurations. The results show that for hot loading at the landing, the yarder was the most utilized machine (85%), and was the bottleneck of the operation, followed by the loader (70%). In the hot loading configuration, 39% of operational delay during truck loading was caused by the loader and was predominantly due to movement of the loader within or between the landings. This was followed by the yarder (19%, due to rigging activities) and the chaser (15%, to maintain the crews’ safety). In the cold loading configuration, delays due to the unavailability of roll-off bins constituted up to 77% of the operational delay. This suggests that the number of bins and trucks hauling biomass has a crucial role in the overall efficiency of the biomass harvesting system, and should be well balanced with loading capacity. Additionally, the choice of hot or cold biomass loading operations is highly dependent on the site and operating conditions.

CAD Of Anticorrosive Protection Of Steel Structures

2019 ◽  
pp. 18-23
Keyword(s):  
Protective Coating ◽  
Computer Aided Design ◽  
Steel Structures ◽  
Cost Effective ◽  
Operating Conditions ◽  
Computational Tool ◽  
Protection Method ◽  
Cost Effective Method ◽  
The Cost ◽  
Aided Design

The choice of cost-effective method of anticorrosive protection of steel structures is an urgent and time consuming task, considering the significant number of protection ways, differing from each other in the complex of technological, physical, chemical and economic characteristics. To reduce the complexity of solving this problem, the author proposes a computational tool that can be considered as a subsystem of computer-aided design and used at the stage of variant and detailed design of steel structures. As a criterion of the effectiveness of the anti-corrosion protection method, the cost of the protective coating during the service life is accepted. The analysis of existing methods of steel protection against corrosion is performed, the possibility of their use for the protection of the most common steel structures is established, as well as the estimated period of effective operation of the coating. The developed computational tool makes it possible to choose the best method of protection of steel structures against corrosion, taking into account the operating conditions of the protected structure and the possibility of using a protective coating.

Optimal Placement of FACTS Devices for Voltage Stability Improvement with Economic Consideration Using Firefly Algorithm

2019 ◽  
Vol 14 (1) ◽  
pp. 5-11
Author(s):  
S. Rajasekaran ◽  
S. Muralidharan
Keyword(s):  
Power Systems ◽  
Voltage Stability ◽  
Firefly Algorithm ◽  
Transmission System ◽  
Operating Conditions ◽  
Optimal Placement ◽  
Voltage Collapse ◽  
Facts Devices ◽  
The Cost ◽  
Bus System

Background: Increasing power demand forces the power systems to operate at their maximum operating conditions. This leads the power system into voltage instability and causes voltage collapse. To avoid this problem, FACTS devices have been used in power systems to increase system stability with much reduced economical ratings. To achieve this, the FACTS devices must be placed in exact location. This paper presents Firefly Algorithm (FA) based optimization method to locate these devices of exact rating and least cost in the transmission system. Methods: Thyristor Controlled Series Capacitor (TCSC) and Static Var Compensator (SVC) are the FACTS devices used in the proposed methodology to enhance the voltage stability of power systems. Considering two objectives of enhancing the voltage stability of the transmission system and minimizing the cost of the FACTS devices, the optimal ratings and cost were identified for the devices under consideration using Firefly algorithm as an optimization tool. Also, a model study had been done with four different cases such as normal case, line outage case, generator outage case and overloading case (140%) for IEEE 14,30,57 and 118 bus systems. Results: The optimal locations to install SVC and TCSC in IEEE 14, 30, 57 and 118 bus systems were evaluated with minimal L-indices and cost using the proposed Firefly algorithm. From the results, it could be inferred that the cost of installing TCSC in IEEE bus system is slightly higher than SVC.For showing the superiority of Firefly algorithm, the results were compared with the already published research finding where this problem was solved using Genetic algorithm and Particle Swarm Optimization. It was revealed that the proposed firefly algorithm gives better optimum solution in minimizing the L-index values for IEEE 30 Bus system. Conclusion: The optimal placement, rating and cost of installation of TCSC and SVC in standard IEEE bus systems which enhanced the voltage stability were evaluated in this work. The need of the FACTS devices was also tested during the abnormal cases such as line outage case, generator outage case and overloading case (140%) with the proposed Firefly algorithm. Outputs reveal that the recognized placement of SVC and TCSC reduces the probability of voltage collapse and cost of the devices in the transmission lines. The capability of Firefly algorithm was also ensured by comparing its results with the results of other algorithms.

Electro-Fenton as a feasible advanced treatment process to produce reclaimed water

2004 ◽  
Vol 50 (2) ◽  
pp. 83-90 ◽  
Author(s):  
A. Durán Moreno ◽  
B.A. Frontana-Uribe ◽  
R.M. Ramírez Zamora
Keyword(s):  
Reclaimed Water ◽  
Electrical Current ◽  
Primary Treatment ◽  
Operating Conditions ◽  
Treatment System ◽  
Continuous Reactor ◽  
Fenton’S Reagent ◽  
Fenton's Reagent ◽  
Fenton’S Reaction ◽  
The Cost

The feasibility of the electro-Fenton process to generate simultaneously both of the Fenton's reagent species (Fe2+/H2O2), was assessed as a potentially more economical alternative to the classical Fenton's reaction to produce reclaimed water. An air-saturated combined wastewater (mixture of municipal and laboratory effluents) was treated in discontinuous and continuous reactors at pH = 3.5. The discontinuous reactor was a 2 L electrochemical laboratory cell fitted with concentric graphite and iron electrodes. The continuous reactor tests used a pilot treatment system comprising the aforementioned electrochemical cell, two clarifiers and one sand filter. Several tests were carried out at different conditions of reaction time (0-60 min) and electrical current values (0.2-1.0 A) in the discontinuous reactor. The best operating conditions were 60 min and 1 A without filtration of effluents. At these conditions, in discontinuous and continuous reactors with filtration, the COD, turbidity and color removal were 65-74.8%, 77-92.3% and 80-100%, respectively. Fecal and total coliforms, Escherichia coli, Shigella and Salmonella sp. were not detected at the end of the pilot treatment system. Electrogeneration of the Fenton's reagent is also economical; its cost is one-fifth the cost reported for Advanced Primary Treatment.

Effects of Cycle Operating Conditions on Combustor Performance

1997 ◽  
Vol 119 (1) ◽  
pp. 45-49 ◽  
Author(s):  
N. T. Davis ◽  
V. G. McDonell ◽  
G. S. Samuelsen
Keyword(s):  
Cost Function ◽  
Duty Cycle ◽  
Load Condition ◽  
Combustion Efficiency ◽  
Operating Conditions ◽  
Nox Emissions ◽  
Variable Geometry ◽  
Oxides Of Nitrogen ◽  
Mixing Processes ◽  
The Cost

To mitigate the environmental impact of next-generation gas turbine combustors, the emission performance at each condition throughout the load duty cycle must be optimized. Achieving this with a single combustor geometry may not be possible. Rather, the mixing processes and airflow splits must likely be modified as a function of load in order to (1) abate the emission of oxides of nitrogen, (2) maintain combustion efficiency, and (3) preclude lean blow-out over the entire duty cycle. The present study employs a model combustor to evaluate combustor performance as a function of load and explore the application of variable geometry to optimize performance at each condition. A parametric variation of flow splits is conducted at each load condition by independently adjusting the primary jet area and swirler choke area. The resultant impact on combustor performance is measured and quantified in terms of a cost function. The cost function is defined to increase with improving combustor performance (e.g., improving combustion efficiency and/or declining NOx emissions). Cycle operating conditions are found to alter the response mappings of efficiency and NOx. As a result, the optimal configuration of the combustor changes as the load is varied over the duty cycle. The results provide guidance on the application of active control.

scholarly journals Designand implementation of wearable single chip system for sensing, processing and transmitting human gesture and motion data

2018 ◽  
Vol 7 (2.8) ◽  
pp. 335
Author(s):  
Venkata Snehith.H ◽  
Likita Ratna D ◽  
Syed Shameem
Keyword(s):  
Inertial Measurement Unit ◽  
Primary Objective ◽  
Measurement Unit ◽  
Human Hand ◽  
Single Chip ◽  
Motion Data ◽  
Wireless Transceiver ◽  
Wearable Electronic ◽  
Pressure Stress ◽  
The Cost

Our work aims at the design of wearable electronic modules that can be assembled as systems for sensing, processing, transmitting, actuating and mimicking human hand gestures and movements, to be used in various robotic, educational, military, medical, industrial, general and hobby applications, the secondary focus of our work is reducing the cost, complexity and assembly of such systems, which are already being used by research centers, laboratories and high-class industries all over the world while the primary objective is to bring these systems down to customizable modular components which could be assembled and combined the way the user wishes to and needs them to be, thereby bringing these concepts closer to a wider range of students, enthusiasts and hobbyists making it easy for them to understand and comprehend these concepts even at the beginner level. In our project, we used commonly available piezo-resistive materials and other household items to make force, pressure, stress, strain and bend sensors and appended them to an Inertial measurement unit, a microcontroller and a wireless transceiver all embedded onto a single chip, to create a simple sensing mechanism that could be worn on a human hand to sense, process and transmit the gestures for actuating and mimicking applications.

scholarly journals EFFECTIVENESS EVALUATION OF STEEL STRENGTH IMPROVEMENT FOR PYRAMIDAL-PRISMATIC BUNKERS

2020 ◽  
Vol 2 ◽  
pp. 30-38
Author(s):  
Yukhym Hezentsvei ◽  
Dmytro Bannikov
Keyword(s):  
Low Temperatures ◽  
High Strength ◽  
Operating Conditions ◽  
Professional Literature ◽  
Plastic Properties ◽  
Repair Work ◽  
Practical Engineering ◽  
Cis Countries ◽  
The Right ◽  
The Cost

In accordance with the recommendations of specialized professional literature, steel pyramidal-prismatic bunkers are projected for a service life of 20 years. However, in practice this term is often twice, or even three times lower. This is especially true for complicated operating conditions, in particular the effect of increased loads and low temperatures. Existing design techniques for such structures, both in European practice and the design practice of Ukraine and other CIS countries do not pay attention to these aspects. Therefore, in the practice of operation, the increased accident rate of steel bunker capacities has already become virtually a common occurrence. One of the possible ways to solve this problem is presented, which consists of using instead of traditional steels of ordinary strength with high plastic properties, steels of increased or high strength with reduced plastic properties. At the same time, clear theoretical recommendations are provided for choosing the right steel depending on the operating conditions, primarily when exposed to increased loads. The recommendations are presented in a form convenient for practical engineering applications. The proposed approach allows to reduce the material consumption of structures of this type on average according to theoretical estimates by 25-30% without reducing their bearing capacity. Their durability is also further enhanced by improving performance at low temperatures. Thus, the applied aspect of such a solution to this above problem is the possibility of increasing the overall reliability of steel bunker capacities, as well as reducing the cost of their periodic maintenance and repair work. A practical illustration of the presented approach is also given on the example of the design of bunkers of a bypass track for supplying charge materials for blast furnaces of one of the metallurgical plants of the northern location. As a result, this created the preconditions for monetary savings of about 0.5 million UAH in prices 2019 (about 20,000 USD)

Method for calculating the thrust and specific thrust of a double-flow gas turbine engine based on the results of tests at the laboratory unit «Flame»

2021 ◽  
pp. 58-64
Author(s):  
S.M. Sergeev ◽  
◽  
V.A. Kudriashov ◽  
N.V. Petrukhin ◽  
◽  
...  
Keyword(s):  
Gas Turbine ◽  
Gas Turbine Engine ◽  
Operating Conditions ◽  
Similarity Criteria ◽  
Fuel Quality ◽  
Jet Engines ◽  
Laboratory Unit ◽  
Turbine Engine ◽  
Specific Thrust ◽  
The Cost

The main technical characteristics of jet engines depend on the fuel quality: thrust and fuel consumption. As a rule, the comparative assessment of real engines is carried by specific values. Specific thrust is one of the most important parameters of the gas turbine engine (GTE). The larger it is, the smaller the required air flow rate through the engine at a given thrust and therefore its dimensions and mass. To date, a system for evaluating the performance properties of fuels based on qualification methods has been created. However, these methods do not allow calculating the thrust and specific thrust of the engine and potentially assessing the effect of fuels on these characteristics. Therefore, the issues of efficient use of fuels for GTE are solved almost exclusively on the basis of tests at testing units with full-scale engines, which are carried out repeatedly, which leads to a significant increase in the cost of testing. The article proposes a method for calculating the thrust and specific thrust of a double-flow gas turbine engine according to the results of tests at a constant volume laboratory unit of bypass type “Flame”. The method is based on modeling the engine operating conditions using the similarity criteria of the bench reactor and the real engine and allows reducing significantly the material and time costs for testing. The experimental of the combustion characteristics of hydrocarbon fuels and the rated values of their thrust and specific thrust for a double-flow gas turbine engine are presented.

Fuel Cell Microgrid with Wind Power Generation

2014 ◽  
pp. 136-166
Keyword(s):  
Power Generation ◽  
Fuel Cell ◽  
Wind Power ◽  
Dynamic Characteristics ◽  
Operating Conditions ◽  
Wind Power Generation ◽  
Small Scale ◽  
Power Characteristics ◽  
Renewable Power ◽  
The Cost

This chapter consists of two sections, ‘Analysis of a Fuel Cell Microgrid with a Small-Scale Wind Turbine Generator’ and ‘Power Characteristics of a Fuel Cell Microgrid with Wind Power Generation.’ An independent microgrid is expected to be effective in cutting greenhouse gas discharge and energy costs. Therefore, the operating conditions of an independent microgrid that supplies power with renewable power sources and fuel cells are investigated in the 1st section. In the 2nd section, the dynamic characteristics of fuel cell microgrid are investigated in numerical analysis, and the cost of fuel consumption and efficiency is also calculated. In addition, the stabilization time of the microgrid and its dynamic characteristics accompanied by wind-power-generation and fluctuation of the power load are clarified.

The Effectiveness of Credit-to-GDP Gap as a Leading Indicator of Banking Crises in India

2021 ◽  
Vol 12 (1) ◽  
pp. 17-37
Author(s):  
Javaid Akhter ◽  
Deepak Tandon ◽  
Gaurav Kulshreshtha
Keyword(s):  
Primary Objective ◽  
Regulatory Framework ◽  
Financial Deepening ◽  
Banking Supervision ◽  
Credit Growth ◽  
Financial Cycle ◽  
Main Indicator ◽  
Credit Cycle ◽  
The Cost ◽  
Gdp Gap

As per the 15th progress report on adoption of the BASEL regulatory framework, published in October 2018 by Basel Committee on Banking Supervision, 26 member jurisdictions now have final rules in force for CCCB. In India, the final rules on CCCB came into force from 5th Feb, 2014; however, the buffer has not been activated by RBI till now as in its assessment, the Credit to GDP gap and other indicators currently do not warrant activation of the countercyclical capital buffer (CCCB). The Basel III regulatory framework for more resilient banks and banking systems, released in December 2010, had introduced the CCCB aimed at strengthening banks defense against the build-up of systemic vulnerabilities. The CCCB is a pre-emptive measure that requires banks to build-up capital gradually as imbalances in the credit market develop. The primary objective of CCCB is to avoid any banking industry stress resulting from wide fluctuations in the credit cycle using the credit-to-GDP gap. In doing so, it raises the cost of capital for banks resulting in moderation of credit demand as well as dissuasion of banks from participating in binge credit growth during the buildup phase itself. The authors have calculated the credit-to-GDP gap (which has been accepted as the main Indicator) for India using the available data and conclude that the buffer guide has historically worked as a reliable EWI in the Indian context. The authors have also concluded that while CCCB is an instrument to protect banks from the bust phase of the financial cycle, it is not an instrument to manage the financial cycle, even if it may potentially have a smoothing impact. An important implication of implementing CCCB using the credit-to-GDP gap as the main indicator for banks and EMEs is that it may hinder beneficial financial deepening, if it is used to actively manage the financial cycle. The authors recommend including the attribution of the Credit-to-GDP GAP w.r.t., the changes attributable to GDP growth, as well as attributable to changes in credit growth in the decision making process to activate CCCB.

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