Journal articles: 'Stand-by operation'

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Brazeau, Randi H., and Marc A. Edwards. "OPTIMIZATION OF ELECTRIC HOT WATER RECIRCULATION SYSTEMS FOR COMFORT, ENERGY AND PUBLIC HEALTH." Journal of Green Building 8, no. 2 (April 2013): 73–89. http://dx.doi.org/10.3992/jgb.8.2.73.

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Hot water recirculation systems (RECIRC) are labeled green and are sometimes mandated in local plumbing codes. Previous work conducted under non-optimized operation schemes demonstrated that these systems actually waste energy and water versus standard (STAND) water heater counterparts. Optimization of RECIRC system operation by minimizing pump operation did improve energy efficiency 6–60%, saving consumers 5–140% annually in associated utility costs. However, STAND systems were still more energy efficient than any of the RECIRC systems. With respect to factors that might influence pathogen growth, reducing RECIRC pump operations increased disinfectant residual by as much as 560% as compared to the baseline RECIRC system; however, STAND systems still had 25–250% more total chlorine residual than any of the RECIRC systems. At 60°C operating temperature, STAND systems have 30–230% more volume at risk for pathogen growth (e.g., volume with temp 37–46°C) than any of the RECIRC systems. Thus, in the context of “green” design, RECIRC systems provide a convenience to consumers in the form of nearly instant hot water, at a cost of higher capital, operating and overall energy costs. RECIRC systems have distinct advantages in controlling pathogens via thermal disinfection but disadvantages in control via secondary disinfection residual.

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Yamashita, Takahiro, Tetsuya Fujimoto, and Koichiro Ishibashi. "Power Valve: for low power operation and low stand-by power." IEICE Electronics Express 2, no. 3 (2005): 64–69. http://dx.doi.org/10.1587/elex.2.64.

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Diniz, Carlos Cezar Cavassin, Felipe Martins de Oliveira, Romano Timofeiczyk Junior, Renato Cesar Gonçalves Robert, Miguel Pesch Tramontini, and Fabio Cordeiro de Brito. "DAMAGE CAUSED BY A WHEELED HARVESTER TO THE RESIDUAL TREES OF A PINUS STAND IN THE FIRST MECHANIZED MIXED THINNING." FLORESTA 50, no. 3 (July 10, 2020): 1547. http://dx.doi.org/10.5380/rf.v50i3.64331.

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The objective of this study was to evaluate the damage caused to the remaining trees of a pinus stand submitted to mechanized thinning by a wheeled harvester. The data were obtained in the operational areas of timber harvesting in a forest company located in the city of Inácio Martins, in the state of Paraná, Brazil. The Pinus stand of the study was 11 years old, and was submitted to the first commercial thinning. The operation was performed by a harvester, characterized by the systematic removal of the 5th planting line to give access to the interior of the stand, followed by selective thinning in the individuals demarcated in the two lines adjacent to the traffic trails. The damage caused to the remaining trees of the stand regarding their numbers, dimensions and location in relation to the harvester’s operation track was evaluated, and the data were analyzed using the Profile Analysis multivariate analysis technique. It was observed that 25% of the remaining trees suffered some kind of damage, being considered a high value, but current to the literature. It was evidenced that the section of the tree in need of greater alert was the base because damages in greater intensity and dimensions were observed to it, which can bring future losses to the stand. Thus, a need for improvements in operational procedures was demonstrated.

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Mikhasek, Andrey, Maxim Rodionov, Nikolay Malyugin, and Artem Klimov. "Stand-by spillways in phreatic dams." MATEC Web of Conferences 196 (2018): 02008. http://dx.doi.org/10.1051/matecconf/201819602008.

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Hydraulic structures operation is always connected with accident risks. The authors analyzed emergency situations which affected dams located on the territory of the USA and Russia. This analysis showed that the most dangerous accident which took place at hydroelectric complexes is an overfall through the crest of the dam accompanied with the formation of washouts and blow-out waves. The most striking example here is the accident at St. Francis dam. According to most researchers, its main cause was the human factor. To reduce economic losses which are due to an accident on the hydro-technical construction and to reduce the risk of human influence, the authors propose to use a stand-by spillway in the body of a phreatic dam. For this purpose, they introduce two constructions. The first construction has a melting insert and a spillway channel fastening made of synthetic materials. The second one has filtering covering of a crest and a downstream slope made of coarse-pored concrete. The researchers perform physical and numerical modeling of the developed structures to compare them. On the basis of laboratory experiments and calculations in the program complex, they obtain discharge coefficient values for various spillways, which can be later used for calculating spillway capacity as well as for its construction.

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Lee, Ha-Lim, and Yeong-Han Chun. "Using Piecewise Linearization Method to PCS Input/Output-Efficiency Curve for a Stand-Alone Microgrid Unit Commitment." Energies 11, no. 9 (September 17, 2018): 2468. http://dx.doi.org/10.3390/en11092468.

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When operating a stand-alone micro grid, the battery energy storage system (BESS) and a diesel generator are key components needed in order to maintain demand-supply balance. Using Unit Commitment (UC) to calculate the optimal operation schedule of a BESS and diesel generator helps minimize the operation cost of the micro grid. While calculating the optimal operation schedule for the microgrid, it is important that it reflects the actual characteristics of the implanted devices, in order to increase the schedule result accuracy. In this paper, a piecewise linearization, on the actual power conditioning system (PCS) input/output-efficiency characteristic curve, has been considered while calculating the optimal operation schedule using UC. The optimal schedule result calculated by the proposed method has been examined by comparing the schedule calculated by a fixed input/output-efficiency case, which is conventionally used while solving UC for a stand-alone microgrid.

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Rachmanov, S. R., S. V. Belodedenko, V. V. Povorotnii, and V. T. Vyshinskii. "Estimation of reliability of the TPA 350 mill working stand housing after a long operation." Ferrous Metallurgy. Bulletin of Scientific , Technical and Economic Information 76, no. 1 (February 7, 2020): 59–67. http://dx.doi.org/10.32339/0135-5910-2020-1-59-67.

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Among the processes, taking place at the shells rolling at automatic mill, the least studied are a working stand housing behavior, which becomes apparent in the form of its dynamic shifting. It can be explained by the fact, that the shell interacting with the rollers and the mandrel is effected by rod mechanism of the mandrel holding at the rolling axis. The possibility of the non-controlled deformed state can be explained also by deviation from the regulation state of anchor bolts fastening system and various defects in the stand housing. It made a foundation to accomplish monitoring of the space state of the TPA 350 automatic mill stand, resulted in registration of the working stand housing stress-deformed state. Besides, it resulted in a task formulation for elaboration of the stand space model aimed at its application for the justification of the strategy of the TPA 350 mill further operation. Results of the study of stress-deformed state of the working stand housing of the TPA 350 automatic mill presented. The study was carried out by the method of finished elements at 3D models. Comprising of the obtained theoretical data with experiment studies of the housing tension confirmed the model adequateness. It was determined, that maximal stresses originate in the zones of the revealed cracks of the working stand housing. The locations of the maximal stresses concentration “migrate” at variation of fastening conditions and the stand housing loading. A function of risk obtained for the stage of a crack originating and for the stage of defect development in the housing. The automatic mill housing safety was exhausted after 50 years of operation. Currently the automatic mill housing operates in the zone of complete risk, accompanying by cracks formation. For the mixed mechanism of crushing, the periods of round defect development in the TPA 350 automatic mill housing determined.

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Wróbel, Nikodem, Michał Rejek, and Grzegorz Królczyk. "Testing of beveled crimp connections made on a prototype stand." Archives of Mechanical Technology and Materials 38, no. 1 (June 28, 2018): 15–22. http://dx.doi.org/10.2478/amtm-2018-0003.

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Abstract The purpose of this study is to form and test inseparable tight joints, commonly used in the construction of heat exchangers, by crimping operation on designed prototype stand. Crimped joints are made by tools in form of cones with two types of shapes, each of the designed tools have got identical forming angle. This study uses two types of connecting blocks and plates, differing in diameters of hole and flange. Elaboration contains a case study of joints being made by the stand, which in addition to the crimping operations for some cases were glued or brazed. The article presents the features of the formed joints, by examining them by destructive testing: Micrography, tensile strength test, and non-destructive testing: Leakage test. The examined elements have been made of aluminum 6060, which is well suited to indirect or direct operations of forming joints for all kinds of coolers or condensers. Elaborated tests and studies in this study allowed to state, that joining the connection block to plate with the small diameter, was more energy-consuming than in sample sets with bigger diameter, use of glue increasing the strength of the joints by 20%, significant strength increase can be obtained after mechanical clinching with brazing operation or modification of geometrical shape of the jaws

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Huang, S. C., J. Y. Yeh, C. T. Chen, and J. C. Chen. "STUDY ON THE EXPLAINABLE ABILITY BY USING AIRBORNE LIDAR IN STAND VALUE AND STAND COMPETITION." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLI-B1 (June 2, 2016): 19–23. http://dx.doi.org/10.5194/isprs-archives-xli-b1-19-2016.

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Forest canopy structure is composed by the various species. Sun light is a main factor to affect the crown structures after tree competition. However, thinning operation is an appropriate way to control canopy density, which can adjust the competition conditions in the different crown structures. Recently, Airborne Light Detection and Ranging (LiDAR), has been established as a standard technology for high precision three dimensional forest data acquisition; it could get stand characteristics with three-dimensional information that had develop potential for the structure characteristics of forest canopy. The 65 years old, different planting density of <i>Cryptomeria japonica</i> experiment area was selected for this study in Nanytou, Taiwan. Use the LiDAR image to estimate LiDAR characteristic values by constructed CHM, voxel-based LiDAR, mu0ltiple echoes, and assess the accuracy of stand characteristics with intensity values and field data. The competition index was calculated with field data, and estimate competition index of LiDAR via multiple linear regression. The results showed that the highest accuracy with stand characteristics was stand high which estimate by LiDAR, its average accuracy of 91.03%. LiDAR raster grid size was 20 m × 20 m for the correlation was the best, however, the higher canopy density will reduce the accuracy of the LiDAR characteristic values to estimate the stand characteristics. The significantly affect canopy thickness and the degree of competition in different planting distances.

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Huang, S. C., J. Y. Yeh, C. T. Chen, and J. C. Chen. "STUDY ON THE EXPLAINABLE ABILITY BY USING AIRBORNE LIDAR IN STAND VALUE AND STAND COMPETITION." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLI-B1 (June 2, 2016): 19–23. http://dx.doi.org/10.5194/isprsarchives-xli-b1-19-2016.

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Forest canopy structure is composed by the various species. Sun light is a main factor to affect the crown structures after tree competition. However, thinning operation is an appropriate way to control canopy density, which can adjust the competition conditions in the different crown structures. Recently, Airborne Light Detection and Ranging (LiDAR), has been established as a standard technology for high precision three dimensional forest data acquisition; it could get stand characteristics with three-dimensional information that had develop potential for the structure characteristics of forest canopy. The 65 years old, different planting density of <i>Cryptomeria japonica</i> experiment area was selected for this study in Nanytou, Taiwan. Use the LiDAR image to estimate LiDAR characteristic values by constructed CHM, voxel-based LiDAR, mu0ltiple echoes, and assess the accuracy of stand characteristics with intensity values and field data. The competition index was calculated with field data, and estimate competition index of LiDAR via multiple linear regression. The results showed that the highest accuracy with stand characteristics was stand high which estimate by LiDAR, its average accuracy of 91.03%. LiDAR raster grid size was 20 m × 20 m for the correlation was the best, however, the higher canopy density will reduce the accuracy of the LiDAR characteristic values to estimate the stand characteristics. The significantly affect canopy thickness and the degree of competition in different planting distances.

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Ursúa, Alfredo, Idoia San Martín, Ernesto L. Barrios, and Pablo Sanchis. "Stand-alone operation of an alkaline water electrolyser fed by wind and photovoltaic systems." International Journal of Hydrogen Energy 38, no. 35 (November 2013): 14952–67. http://dx.doi.org/10.1016/j.ijhydene.2013.09.085.

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Kędzierski, Piotr, Tadeusz Niezgoda, and Grzegorz Sławiński. "Development of Stand for Rock Material Fracturing in Laboratory Conditions." Solid State Phenomena 240 (August 2015): 94–97. http://dx.doi.org/10.4028/www.scientific.net/ssp.240.94.

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The paper presents a description of the stand for rock material fracturing in laboratory conditions. Requirements to be met by fracturing stands were formulated. Proper operation of the test stand was verified by marble sample fracturing. Many of technical details of the developed stand were given, which may be useful for readers designing their own stands.

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DROŹDZIEL, Paweł, and Paweł KORDOS. "PROPOSITION OF NEW SINGLE TEST CYCLE OF INTERNAL COMBUSTION ENGINE DURING STAND RELIABILITY TESTS." Scientific Journal of the Military University of Land Forces 159, no. 1 (January 3, 2011): 50–57. http://dx.doi.org/10.5604/01.3001.0002.2860.

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A test-stand reliability evaluation of automotive internal combustion engines is carried out so as to determine the selected reliability parameters, such as an average occurrence of defects, an average frequency of part exchange, an average frequency of engine regulation or the wear of selected engine components. The values of these indicators make it possible to estimate the durability of components used as well as of the whole structure of the engine. During reliability test-stand research, the engine is run according to multiple repeated cycles of operation. The conditions of engine operation during reliability tests can be characterized by time invariability and extreme values of rotational speed and torque. In this article the authors prove that the conditions of real automotive engine operation are much more diversified (city driving) with a high share of partial loads (intercity driving). Another significant difference in test-stand reliability evaluation and real operation is the frequency of engine start-ups. In real conditions engine start-ups are far more frequent. The authors propose a new test cycle, which will enable reproducing the real engine operation conditions in stand tests. Characteristic features of this test include more frequent starts and distinguishing between the two kinds of variability in conditions of operation: city and intercity driving, with “lighter” values of rotational speed and torque.

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Ivanovа, V. R., and L. V. Fetisov. "DEVELOPMENT OF TRAINING BENCH FOR EFFECTIVE AND SAFE OPERATION OF BACKUP POWER AT INDUSTRIAL ENTERPRISES." Proceedings of the higher educational institutions. ENERGY SECTOR PROBLEMS 20, no. 9-10 (January 24, 2019): 120–28. http://dx.doi.org/10.30724/1998-9903-2018-20-9-10-120-128.

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The paper suggests the description and development of the demonstration stand «Automatic switch of stand-by power supply" for possibility of visual study and understanding of the multi-purpose power supply to ensure the reliability of electricity supply to consumers.

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Sarkar, Shreya, and Anindya Bose. "Lifetime Performances of Modernized GLONASS Satellites: A Review." Artificial Satellites 52, no. 4 (December 1, 2017): 85–97. http://dx.doi.org/10.1515/arsa-2017-0008.

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AbstractGLONASS, successfully operating during 1990s became unusable by early 2000s. Following a revitalization and modernization plan since 2004, GLONASS constellation has been completed again by the end of 2011 and the use of GLONASS is gaining popularity. Because of the previous experience, some scepticism exists among the stakeholders in using GLONASS for reliable solution and application development. This paper critically reviews the operational lifespan of GLONASS satellites launched between 2004 and 2016, as this is an important contributor towards reliability and sustained operation of the system. For popularization and extracting full benefits of GLONASS as stand-alone system or as an active component of multi-GNSS, major issues of assuring the minimum sufficient GLONASS constellation (of 24…23 satellites), efficient design implementation and the modernized ground control segment development and operation need to be properly taken care of by the system operators.

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Lyashuk, Oleg, Ruslan Zaverukha, Yuriy Pyndus, Yuriy Vovk, and Alexander Pyndus. "Experimental and analytical study of petrol engine electromagnetic injectors control system." Scientific journal of the Ternopil national technical university 100, no. 4 (2020): 97–105. http://dx.doi.org/10.33108/visnyk_tntu2020.04.097.

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A laboratory stand for the study and diagnostics of the fuel supply system functional elements and for the education process efficiency improvement of laboratory research has been developed. The laboratory stand design is an illustrative one and can be used for the general assessment of the ICE selected control system quality. The assessment of parameters characterizing the fuel injection efficiency by separate injectors of the engine in several operation modes has been made using the stand under discussion. The experimental research has been conducted and main characteristics of the fuel supply by electromagnetic injectors of the engine under study for some operation modes have been obtained. The modeling has been conducted using the well-known techniques of regression analysis.

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Nguyen, Thanh Hai, Tan Luong Van, Asif Nawaz, and Ammar Natsheh. "Feedback Linearization-Based Control Strategy for Interlinking Inverters of Hybrid AC/DC Microgrids with Seamless Operation Mode Transition." Energies 14, no. 18 (September 7, 2021): 5613. http://dx.doi.org/10.3390/en14185613.

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This study proposes an advanced control scheme for the interlinking inverters of the hybrid AC/DC microgrids, which facilitates a seamless transition between grid-connected and stand-alone/islanding modes for the microgrid. Due to a nonlinear relationship between the terminal voltages of the voltage-source inverter (VSI) interfacing through inductor–capacitor (LC) filters with the grid voltages and currents, a feedback linearization technique (FLT) is employed to control the interlinking VSI under both grid-connected and islanding operations. The FLT-based current controllers are applied in the grid-connected mode, in which they adjust the power exchange between the DC and AC subgrids and mitigate the distortion of the grid currents produced by nonlinear loads. Under the stand-alone operation, the AC bus voltages are directly regulated by the FLT-voltage controllers of the interlinking VSI. In order to reduce the inrush currents and voltage overshot at the instant of mode switching, the FLT-based controllers are performed all the time regardless of the operating modes, where the voltage references for the VSI are not changed abruptly. The control performance of the VSI is highly satisfactory with low-transient overshoot values of the voltages and currents and low total harmonic distortion (THD) values of the grid currents and AC bus voltages are about 3.5% and 2.7%, respectively, under the nonlinear load condition. The validity of the new control strategy is verified by the simulation work, which investigates the operation of a hybrid AC/DC microgrid.

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Noroozian, Reza, Gevorg Gharehpetian, Mehrdad Abedi, and Mishel Mahmoodi. "Grid-Tied and Stand-Alone Operation of Distributed Generation Modules Aggregated by Cascaded Boost Converters." Journal of Power Electronics 10, no. 1 (January 20, 2010): 97–105. http://dx.doi.org/10.6113/jpe.2010.10.1.097.

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Kreimer, Joseph, and Abraham Mehrez. "An optimal operation policy for real-time n-server stand-by systems involving preventive maintenance." European Journal of Operational Research 69, no. 1 (August 1993): 50–54. http://dx.doi.org/10.1016/0377-2217(93)90089-6.

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Dufo-López, Rodolfo, L. Alfredo Fernández-Jiménez, Ignacio J. Ramírez-Rosado, J. Sergio Artal-Sevil, José A. Domínguez-Navarro, and José L. Bernal-Agustín. "Daily operation optimisation of hybrid stand-alone system by model predictive control considering ageing model." Energy Conversion and Management 134 (February 2017): 167–77. http://dx.doi.org/10.1016/j.enconman.2016.12.036.

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Sznajder, Joanna. "The Analysis of the Digital AC Motor Speed Control System Operation." Zeszyty Naukowe Akademii Marynarki Wojennej 212, no. 1 (March 29, 2018): 125–36. http://dx.doi.org/10.2478/sjpna-2018-0007.

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Abstract The article presents the analysis of the automatic alternate current motor control system, carried out by the author. The automatic control system has been implemented on the existing laboratory stand, containing: the squirrel-cage asynchronous motor and the frequency inverter. The existing stand imposed one of the available speed control methods for the motor and the necessity of the appropriate elements selection for the automatic control system [1]. The automatic control system has been designed and created as the constant value follow-up digital controller. To designate the parameters of the control object the unit step method of was used. After registering the output changes caused by the unit step, the characteristic curve was received that allowed to determine the alternative transmittance of the control object which, in turn, has made possible to find the appropriate controller settings.

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Miyajima, Ricardo Hideaki, Paulo Torres Fenner, Gislaine Cristina Batistela, and Danilo Simões. "Effect of Feller-Buncher Model, Slope Class and Cutting Area on the Productivity and Costs of Whole Tree Harvesting in Brazilian Eucalyptus Stands." Forests 12, no. 8 (August 15, 2021): 1092. http://dx.doi.org/10.3390/f12081092.

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The operational productivity and costs of tree felling operations can be influenced by several factors, among which, the machine characteristics, slope class, the cutting area and the individual volume of the trees stand out. Thus, the main objective of the present study was to analyze the productivity and production cost for two feller-bunchers with different technical characteristics operating in a eucalyptus forest. The productivity was calculated from a time study and the factors analyzed were two feller-buncher models, two slope classes, and two cutting areas. The machine cost per scheduled hour was based on the methodology of the Food and Agriculture Organization of the United Nations. Analysis of the results showed that the felling and turn operational elements occupied the most time in the operational cycle of feller-bunchers. The machine cost per scheduled hour was USD 69.69 h−1 for feller-buncher 1 and USD 102.03 h−1 for feller-buncher 2. In conclusion, the distinct technical characteristics of feller-bunchers were found to influence the productivity and, consequently, the cost, of the felling operation during the harvesting of whole eucalyptus trees.

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Han, H.-Sup, Thomas W. Steele, and Loren D. Kellogg. "DamQuick: A New Method for Rapidly Assessing Residual Stand Damage During Partial Timber Harvests." Western Journal of Applied Forestry 18, no. 2 (April 1, 2003): 81–87. http://dx.doi.org/10.1093/wjaf/18.2.81.

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Abstract The increasing frequency of partial timber harvest prescriptions has created the need for an efficient and accurate method of assessing residual stand damage. In this study, we developed and tested a new sampling method that exploits the general pattern of residual stand damage being concentrated near primary transport routes. The method, termed DamQuick, consists of systematic belt transects located immediately adjacent and parallel to the harvesting operation's extraction corridors. Plot measures of tree wounding are scaled by sampling intensity and a concentration factor to yield stand-level estimates of residual damage. The method was evaluated for a skyline thinning operation in western Oregon. DamQuick damage estimates were compared with actual damage levels obtained from a 100% survey for three thinning treatments—30, 60, and 100 residual trees/ac. The mean DamQuick estimates were statistically similar to actual stand damage levels (t = 0.366–0.651, P = 0.531–0.725) for all thinning treatments, with mean estimation errors (standard errors) ranging from 0.7% (0.9%) to 2.1% (4.4%). Operationally, DamQuick was easy to implement. The primary transport routes provided ready stand access, which facilitated plot location and establishment. West. J. Appl. For. 18(2):81–87.

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Feitosa, Jardênia R., Haroldo C. Fernandes, Paulo R. Cecon, Daniel M. Leite, Filipe M. T. Nery, and Janielle S. Pereira. "Onion yield as a function of soil tillage system and soil water content." Revista Brasileira de Engenharia Agrícola e Ambiental 24, no. 2 (February 2020): 115–20. http://dx.doi.org/10.1590/1807-1929/agriambi.v24n2p115-120.

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ABSTRACT Excessive tillage operations under inadequate conditions can raise the cost of agricultural production and lead to soil degradation without adequate crop response. The objective of this study was to evaluate the onion crop response to soil water contents and tillage systems. Three tillage systems were evaluated: P1 (plowing + two harrowings + two seedbed raising operations), P2 (two harrowings + one seedbed raising operation), P3 (one harrowing + one seedbed raising operation); and four soil water contents: 12, 15, 23 and 26%. The experiment was conducted in the irrigated perimeter of Tourão, Juazeiro, BA, Brazil (9° 24’ 7.3” S; 40° 26’ 8.7” W and altitude of 368 m), in 2017, and was installed in split plots, in a randomized block design, with four repetitions. Water contents were arranged in the plots and tillage systems in the subplots. Crop response to the applied treatments was evaluated through the determination of the emergence speed index of the seedlings, regularity of the longitudinal distribution of seedlings, final stand, total and marketable yields of the crop and yield per bulb transverse diameter class. The variation of soil water content had a quadratic effect on the variables emergence speed index, final stand and total onion yield. The treatments did not significantly affect the longitudinal distribution of plants and marketable yield. The tillage system composed of one harrowing and one seedbed raising operation showed to be the most appropriate for onion cultivation by direct seeding.

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Rédei, Károly, Zsolt Keserű, Imre Csiha, János Rásó, Csaba Kovács, and Borbála Antal. "Tending operation model for red oak stands." Acta Agraria Debreceniensis, no. 72 (May 16, 2017): 133–36. http://dx.doi.org/10.34101/actaagrar/72/1604.

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Red oak (Quercus rubra L.) is our most important exotic oak species, that possesses growing culture with almost one hundred years in our country. Plantation character of red oak growing predominates principally by applied regeneration method (mostly artificial), regular planting space, applying defined method and planting space regulation system. Forest tending model for red oak, that considered stopgap in the native literature is intended to serving the latter. Especially important equation in the viewpoint of stand growing, that describes relationship of stem number (N, in hectare) and diameter at breast height (D1.3 in cm) is: N=e9.80220-1.12607lnD1.3.

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Rock, Stephanie, M. Reza Hosseini, Bahareh Nikmehr, Igor Martek, Sepehr Abrishami, and Serdar Durdyev. "Barriers to “green operation” of commercial office buildings." Facilities 37, no. 13/14 (October 7, 2019): 1048–65. http://dx.doi.org/10.1108/f-08-2018-0101.

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Purpose The built environment is a major source of carbon emissions. However, 80 per cent of the damage arises through the operational phase of a building’s life. Office buildings are the most significant building type in terms of emission-reduction potential. Yet, little research has been undertaken to examine the barriers faced by building operators in transitioning to a green operation of the office buildings in their care. This study aims to identify those barriers. Design/methodology/approach Building facilities managers with between 7 and 25 years’ experience in operating primarily Melbourne high-rise office buildings were interviewed. The sample was taken from LinkedIn connections, with ten agreeing to participate in semi-structured interviews – out of the 17 invitations sent out. Interview comments were recorded, coded and categorised to identify the barriers sought by this study. Findings Seven categories of barriers to effecting green operation of office buildings were extracted. These were financial, owner-related, tenant-related, technological, regulatory, architectural and stakeholder interest conflicts. Difficulties identifying green operation strategies that improved cost performance or return on investment of buildings was the major barrier. Practical implications Government, policymakers and facilities managers themselves have been struggling with how to catalyse a green transition in the operation of office buildings. By identifying the barriers standing in the way, this study provides a concrete point of departure from which remedial strategies and policies may be formulated and put into effect. Originality/value The uptake of green operation of office buildings has been extremely slow. Though barriers have been hypothesised in earlier works, this is the first study, to the best of the authors’ knowledge, that categorically identifies and tabulates the barriers that stand in the way of improving the green operational performance of office buildings, drawing on the direct knowledge of facilities experts.

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Tomoiaga, Bogdan, Mircea D. Chindris, Andreas Sumper, and Mousa Marzband. "The Optimization of Microgrids Operation through a Heuristic Energy Management Algorithm." Advanced Engineering Forum 8-9 (June 2013): 185–94. http://dx.doi.org/10.4028/www.scientific.net/aef.8-9.185.

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The concept of microgrid was first introduced in 2001 as a solution for reliable integration of distributed generation and for harnessing their multiple advantages. Specific control and energy management systems must be designed for the microgrid operation in order to ensure reliable, secure and economical operation; either in grid-connected or stand-alone operating mode. The problem of energy management in microgrids consists of finding the optimal or near optimal unit commitment and dispatch of the available sources and energy storage systems so that certain selected criteria are achieved. In most cases, energy management problem do not satisfy the Bellman's principle of optimality because of the energy storage systems. Consequently, in this paper, an original fast heuristic algorithm for the energy management on stand-alone microgrids, which avoids wastage of the existing renewable potential at each time interval, is presented. A typical test microgrid has been analysed in order to demonstrate the accuracy and the promptness of the proposed algorithm. The obtained cost of energy is low (the quality of the solution is high), the primary adjustment reserve is correspondingly assured by the energy storage system and the execution runtime is very short (a fast algorithm). Furthermore, the proposed algorithm can be used for real-time energy management systems.

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Szurgacz, Dawid. "Analysis characteristics determination of electrohydraulic control system operation to reduce the operation time of a powered roof support." E3S Web of Conferences 29 (2018): 00007. http://dx.doi.org/10.1051/e3sconf/20182900007.

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The article discusses basic functions of a powered roof support in a longwall unit. The support function is to provide safety by protecting mine workings against uncontrolled falling of rocks. The subject of the research includes the measures to shorten the time of roof support shifting. The roof support is adapted to transfer, in hazard conditions of rock mass tremors, dynamic loads caused by mining exploitation. The article presents preliminary research results on the time reduction of the unit advance to increase the extraction process and thus reduce operating costs. Conducted stand tests showed the ability to increase the flow for 3/2-way valve cartridges. The level of fluid flowing through the cartridges is adequate to control individual actuators.

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Song, Seungjeong, Minseok S. Kim, Jaeyeon Lee, and Sungyoung Choi. "A continuous-flow microfluidic syringe filter for size-based cell sorting." Lab on a Chip 15, no. 5 (2015): 1250–54. http://dx.doi.org/10.1039/c4lc01417k.

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Schweier, Janine, and Christian Ludowicy. "Comparison of A Cable-Based and a Ground-Based System in Flat and Soil-Sensitive Area: A Case Study from Southern Baden in Germany." Forests 11, no. 6 (May 29, 2020): 611. http://dx.doi.org/10.3390/f11060611.

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The results of this study showed that the application of cable-based systems in flat terrain must not necessarily be more cost intensive than its application in other terrains. In recent years, criteria other than purely economic ones have been taken into account in forest management decisions, with the aim of avoiding ecosystem damage and promoting better ecosystem services. Since precipitation in winter is becoming more intensive and weeks with frozen soils are becoming rare, one option might be the use of cable-based instead of ground-based extraction systems. Both vary in terms of economy and flexibility. Thus, it is important to make reliable estimates of potential costs and benefits before an operation is conducted. The aim of this study was to analyze a cable-based and a ground-based extraction system that could be applied to a forest stand in a flat and soil-sensitive area. The study, based on a cable-based operation, was conducted in a mixed forest stand that was vulnerable to traffic. Furthermore, we modeled an alternative operation focusing on a ground-based system, addressing the soil vulnerability by considering manual felling, processing, and use of a combi-forwarder for extraction. In the cable-based system, yarding productivity was high (20.3 m3ub/PMH15) due to several reasons, such as a high share of larger dimension timber, the fact that heavy timber was partially de-limbed and processed motor-manually in the stand, the fact that a mini forestry crawler was used for pre-winching the material and finally due to the experience of the operators. Resulting costs for harvesting and extraction were on average €27.8/m3ub. In the ground-based system, costs were on a comparable level (€28.30/m3ub). In our case, the application of a cable yarder in flat terrain was a good alternative and should be considered in future forest management to support environmentally friendly operations and allow independent planning of the operation.

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Doubrava, Karel, and Jiří Kuželka. "Turbine Blade Loading and Experimental Verification." Applied Mechanics and Materials 486 (December 2013): 273–76. http://dx.doi.org/10.4028/www.scientific.net/amm.486.273.

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The paper describes process of verification of FEM model of turbine rotor blade fatigue tests. Design of new turbine blade is tested on experimental stand, where load situation is similar to load of rotor blade of steam turbine during operation. Real load of blade and boundary condition on experimental stand was monitored by means of strain gauges set. Experimental data were compared with the computed results of several FEM models.

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Liu, Tianyi, and Hai Bao. "A Two-Stage PV Accommodation Optimization in Jinzhai County, Anhui Province with Hydropower as Stand-By Unit." E3S Web of Conferences 252 (2021): 01017. http://dx.doi.org/10.1051/e3sconf/202125201017.

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In respond to the national “Photovoltaic Poverty Alleviation” and renewable energy accommodation policy, this paper proposes a two-stage PV accommodation optimization strategy based on improved PSO, PV forecast, and hydropower dispatch to tackle with the instability caused by distributed PV, since Jinzhai County, Anhui Province has both sufficient hydropower and photovoltaic. In the first stage, the hydropower reserve capacity of each period of the next day is optimized according to the PV forecast. In the second stage, real-time online optimization is carried out using the operation data to determine the amount of power generated by each PV source during each period. Finally, the optimization strategy is verified by simulations using grid operation data in Jinzhai, and the comparison is made with the thermal power standby unit. The results show that the hydropower units which has higher climbing rate can immensely increase the photovoltaic consumption, reduce the power loss and enhance the voltage stability of the network.

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Matsumoto, Ken. "A Guide to Response Evaluation for Oil Spill Combat in Japan." International Oil Spill Conference Proceedings 1991, no. 1 (March 1, 1991): 87–91. http://dx.doi.org/10.7901/2169-3358-1991-1-87.

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ABSTRACT There are many ways to evaluate the overall performance of an oil spill response operation. There is, or there should be, however, a common standpoint for looking at such operations, irrespective of the size of the spill. Lessons learned through an incident, however trivial, can provide valuable clues to the future improvement of the operation in refineries and oil terminals. But the number of incidents at one location is too few to stand the test of analysis. Evaluation by a variety of methods is now possible based on information and data available through the worldwide news and reporting networks. This paper presents a guideline, which is widely accepted by the Japanese oil industry, for evaluating responses to oil spills, and introduces a concise equation based on the rating of many response elements.

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Balslev-Olesen, P., A. Lynggaard-Jensen, and Claus Nickelsen. "Pilot-Scale Experiments on Anaerobic Treatment of Wastewater from a Fish Processing Plant." Water Science and Technology 22, no. 1-2 (January 1, 1990): 463–74. http://dx.doi.org/10.2166/wst.1990.0170.

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From November 1985 to May 1988, experiments with anaerobic treatment of wastewater from a fish cannery were carried out at the Water Quality Institute (WQI) at Aarhus, Denmark. An anaerobic fixed filter (AF) reactor and an anaerobic fluidized bed (AFB) reactor were used for the pilot-scale experiments. The reactors were monitored and controlled by a microcomputer. The aim of the experiments was to determine the biogas yield from COD reduction and to show the efficiency of the reactor as a function of the following operation parameters: Volumetric organic load, 3–15 kg COD/(m3·day); temperature, 30–35°C, pH (control of); salinity, 1–4%. Operational data are presented, including start-up after stand-by periods of varying lengths, from one day to three months. Both reactors showed excellent capability of handling load variations and were capable of quick start-up and high efficiency even after long stand-by periods.

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Hoffman, Benjamin F., David C. Wedge, and Charles J. Gadzik. "Scandinavian Thinning Techniques in a Natural Northeastern Softwood Stand." Northern Journal of Applied Forestry 4, no. 1 (March 1, 1987): 38–42. http://dx.doi.org/10.1093/njaf/4.1.38.

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Abstract The applicability of Scandinavian thinning techniques to small-diameter northeastern softwood stands was tested in a hemlock stand in central Maine. Cutting used motormanual techniques in which the cutter felled, limbed, bucked and piled 8-ft bolts for extraction to trailside by a small tractor and winch. Sixteen-foot lengths were also cut in order to compare the relative merits of the two sizes. To simulate radio control, the winch was activated by a retractable nylon line that permitted the operator to control it remotely from within the stand. A small, tracked forwarder transported the wood to roadside landings. Total roadside cost of the operation was $42.86 per cord, but a cost of $37.87 is considered attainable. The most expensive and most difficult to improve function is cutting, which is most influenced by the small tree size. In this case, 27.5 trees were cut per cord, compared with 10-15 found in most commercial operations. Costs are unacceptable, but the technique may be viable for woodlot owners with limited equipment and low wage requirements. North. J. Appl. For. 4:38-42, March 1987

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Kortas, Paweł. "Methods of Determination of the Fuel Consumption of the Locomotive Diesel-Electric Propulsion System for Regular Operating Conditions." Key Engineering Materials 597 (December 2013): 77–86. http://dx.doi.org/10.4028/www.scientific.net/kem.597.77.

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In order to determine the fuel consumption during operation of locomotive it is necessary to work out the characteristics of fuel consumption vs. power produced by propulsion system. These characteristics can be obtained during tests in a diagnostic stand equipped with water rheostat, which allows to simulate any load on the main generator. Another method depends on utilization data from monitoring system of the propulsion system, obtained during regular operation of the locomotive. The main disadvantage of this method is lack of long-term constant loads, which is caused by frequently changing operating conditions. This has a major impact on the measuring error, which can be minimized by suitable utilization of a large number of measurements. Practical remarks of those methods usage have been presented in this paper.

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Tavankar, F., B. Majnounian, and A. E. Bonyad. "Felling and skidding damage to residual trees following selection cutting in Caspian forests of Iran." Journal of Forest Science 59, No. 5 (May 30, 2013): 196–203. http://dx.doi.org/10.17221/53/2012-jfs.

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The felling and skidding damage to residual trees was investigated in a selectively cutting operation in the Caspian forest of Iran. The logging operation was performed by chainsaw and cable skidder. Prelogging, after felling and skidding operations residual tree injuries (species, DBH and damage) were inventoried by systematic plot sampling. Two types of tree damage were observed: destroyed and injured. In this study felling operations mainly injured trees whereas skidding was the main cause of destruction. The percentage of destroyed and injured residual trees by felling operations was 1.4% and 3.4%, whereas the percentage of destroyed and injured residual trees by skidding operations was 5.2% and 11.1%. About 87% of destroyed trees were found in the DBH class smaller than 22.5 cm. Maple and Alder were the most damaged trees among the other trees species. Damage to the lower bole and wood damaged intensity were the most common type of injury. To reduce the stand damage, skid trails should be planned before felling and felling directions should be predetermined. In the selection cutting management, limiting logging damage to residual trees must therefore remain a major objective.    

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Jun, Myoungjae, Hieyong Jeong, and Yuko Ohno. "Operation of assistive apparatus through recognition of human behavior: Development and experimental evaluation of chair-typed assistive apparatus of nine-link mechanism with 1 degree of freedom." Advances in Mechanical Engineering 12, no. 7 (July 2020): 168781402093889. http://dx.doi.org/10.1177/1687814020938899.

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Because of deterioration of strength, range of joint motion, and balance ability, most care-dependent older adults require assistance to move from a seated position to a standing position. Although many sit-to-stand assisting apparatuses consisting of a seat, power transmission mechanism, and sensors have been developed, most of movements depend several actuators as the power transmission mechanism. This study aims to develop the chair-typed apparatus of nine-link mechanism with 1 degree of freedom at first, then to prove the possibility that the apparatus can be operated through the recognition of human behavior by one sensor. Here, the nine-link mechanism is divided into two mechanisms: the five link for raising the height; the four link for rotating. The mechanical part enables two input links for two mechanisms to be driven by one linear actuator simultaneously. The measurement with the infrared sensor enables the assistive apparatus to be operated automatically while patterns from measured data help the apparatus recognize what the user want to do: one is the sit-to-stand movement; the other is the stand-to-sit movement. It is discussed that the operating method through the human behavior is helpful for most older adults who are not familiar with the operation of machine.

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WATAGAMI, Yukiharu, Takehiko MURAKAWA, Keigo UTUNOMIYA, and Masaru NAKAGAWA. "An approach to Full-text Search for Bibliographic Data of Ancient Documents by means of Stand-alone Operation." Joho Chishiki Gakkaishi 20, no. 2 (2010): 189–94. http://dx.doi.org/10.2964/jsik.20_189.

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Sokolovsky, Vladimir, Victor Meerovich, Shaul Goren, Lidia Chubraeva, and Istvan Vajda. "Joint Operation of a Solar Station and a Superconducting Kinetic Energy Storage Device." Materials Science Forum 721 (June 2012): 263–68. http://dx.doi.org/10.4028/www.scientific.net/msf.721.263.

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It was experimentally shown that joint application of a solar station and a superconducting flywheel (a kinetic energy storage device) can solve the main problem of renewable energy sources: to provide uninterrupted and controlled power supplying. The storage device changes its operation mode (stand-by, charging, discharging) practically without any delay and its use leads to an increase of the transient stability of a power system.

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Kulinowski, Piotr, Piotr Kasza, and Jacek Zarzycki. "Influence of Design Parameters of Idler Bearing Units on the Energy Consumption of a Belt Conveyor." Sustainability 13, no. 1 (January 5, 2021): 437. http://dx.doi.org/10.3390/su13010437.

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This publication presents the results of laboratory tests of idler rolling resistance under operational loads. Operational loads are understood as radial and axial forces acting on the idler, with values corresponding to those that occur in the conditions of its operation in copper ore mines. Knowing the rolling resistance is important not only at the stage of conveyor design, selection of the drive power or calculations of the necessary belt strength, but also when improving and searching for new idler design solutions. The idlers adopted for this research were differentiated in terms of bearings and idler axial clearance. The investigations were carried out on a unique test stand designed and built by the authors. The construction of the stand enables simulating operational loads while measuring the rolling resistance. The test rig measures idler bearing losses and rolling drag, not belt indentation rolling resistance. The object of the research were ø133×465 idlers, which are most commonly used in the raw materials industry. The results show the possibility of reducing the belt conveyor energy consumption by appropriate selection of the design features of the idler bearing unit.

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Kang, Jie, Jian Hui Di, and Jin Peng Kang. "Study on a Testing Device of Automobile Brake Drum Running-In and Braking Force." Applied Mechanics and Materials 321-324 (June 2013): 1583–86. http://dx.doi.org/10.4028/www.scientific.net/amm.321-324.1583.

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This paper introduces a kind of testing device for automobile brake drum running-in stand and braking force, this device combines the existing car drum brake with braking force by means of increasing the frequency conversion speed control device and redesigning control system. Using this device will reduce the occupied site and realize the conversion between two functions in situ and save the operation time of function conversion. It can completely replace the original car drum brake running-in stand and braking force test bench.

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Kaldellis, J. K. "Minimum Stand-alone Wind Power System Cost Solution for Typical Aegean Sea Islands." Wind Engineering 26, no. 4 (July 2002): 241–55. http://dx.doi.org/10.1260/030952402321039430.

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Stand-alone wind power systems provide a solution for the electrification of isolated families. However, optimal sizing is usually based on simplified cost analysis of the initial installation. In this paper, a complete long-term energy production cost investigation is developed. This considers the fixed and variable costs of maintenance, operation and financing, in addition to initial costs. The new model includes local economic parameters, technological improvements concerning the system components and the local wind characteristics. By using the proposed model, the requirements and costs of the appropriate stand-alone system are recalculated and then compared with those based only on the initial installation. According to the results obtained, the proposed configuration uses larger wind turbines and smaller batteries than that the installation-only scenario. Finally, the energy production values are compared to available operational data from autonomous thermal power plant on various small Greek islands.

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Słowik, Maciej, and Zdzisław Gosiewski. "Base Station for Monitoring of Unmanned Aerial Vehicle Flight." Solid State Phenomena 198 (March 2013): 182–87. http://dx.doi.org/10.4028/www.scientific.net/ssp.198.182.

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A configuration of universal base station designed to use mobile networks for long-range transmission of telemetry data is described in the paper. Types of cellular networks and modes of their operation are presented. Next, GPRS system is shown as a possible method of data transmission between UAV and Base Station. Communication modes of the station can be augmented by additional close-range communication system based on Xbee modules. The configuration and integration of test stand for telemetric signals monitoring are shown. Finally, the modes of possible operations based on the conditions of mobile networks are described.

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MAMALA, Jarosław. "The analysis of spark ignition engine short-time supercharging." Combustion Engines 139, no. 4 (November 1, 2009): 3–11. http://dx.doi.org/10.19206/ce-117163.

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The paper presents the analysis of improvement of spark ignition engine operation indexes by means of short-time supercharging. The simulation and engine test stand investigation results of the air flow in the spark ignition combustion engine intake system have been shown here.

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Schroering, J. D., B. L. Lanford, and B. J. Stokes. "Franklin 105 Feller Buncher: Fifth-Row Thinning Application." Southern Journal of Applied Forestry 9, no. 2 (May 1, 1985): 110–13. http://dx.doi.org/10.1093/sjaf/9.2.110.

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Abstract Plantation thinning requires machinery capable of operating in confined conditions while causing minimal damage to the residual stand and site. The Franklin 105 feller buncher, equipped with a Tidewater DL-12 accumulating shear, was studied in a fifth-row thinning application to determine variables affecting machine operation and productivity. Machine operation was divided into two elements: (1) move-to-tree and shear tree; and (2) move-to-dump, dump load, and bunch alignment. Move-to-tree and shear times were influenced by the number of residual trees per acre and whether the operator was row/corridor harvesting or selective thinning, while move-to-dump, dump load, and bunch alignment times were influenced by the average diameter and the number of trees in the shear head prior to dumping. Production costs were higher for selective thinning than for row/corridor harvesting.

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Roque, Paxis Marques João, Shyama P. D. Chowdhury, and Zhongjie Huan. "Improvement of Stand-Alone Solar PV Systems in the Maputo Region by Adapting Necessary Parameters." Energies 14, no. 14 (July 19, 2021): 4357. http://dx.doi.org/10.3390/en14144357.

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With the energy crisis and the constant blackout in the Mozambique Power Company grid, the option of applying solar photovoltaic (PV) systems has been one of the most used alternatives in the neighborhoods of the Maputo region. However, inefficient power delivery caused by unproper sizing and installation of stand-alone solar PV systems has been contributing to the low utilization of solar energy potential in the Maputo region. The optimal sizing and installation of the solar PV system is addressed to evaluate the influence of installation and operation parameters on the power output of PV modules. In this topic, PV modules parameters such as cell temperature, the module’s slope and azimuth angles, the losses caused by excessive heating of the module cells, shadows and dust on the PV module and the cooling process at the back of the module are assessed in order to find out the consequence of inadequate installation and operation parameters of solar PV systems in the Maputo region. The proper sizing and installation of the stand-alone solar PV system is fundamental to guarantee the continuous and efficient supply of power and, thus, different tools and techniques have been applied. This study will deal with the hybrid optimization of multiple energy resources (HOMER) and system advisor model (SAM), to size and improve power generation of solar PV systems. This study concluded that for the Maputo region, the optimal tilt angle is 23 ± 2° and the azimuth angle is 11 ± 2°. In addition, for optimization of the tilt and azimuth angles, it also examined the effect of module backside ventilation and proved that the system’s power generation increases with the rise of spacing between the module and the wall, since the strategy prevents the decline of the module cells efficiency. However, the maximum recommended spacing between the PV module and the mounting wall is about 0.4 m, since an effort to increase the spacing up to this level results in an insignificant growth of power output.

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Pokrovskaya, O. D. "A stand for researching the dynamics and strength of a freight wagons bogie." Transport Technician: Education and Practice 2, no. 3 (September 14, 2021): 327–38. http://dx.doi.org/10.46684/2687-1033.2021.3.327-338.

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The purpose of the study is to characterize the laboratory equipment of a new generation that meets the requirements that are imposed today on the training of specialists in the rolling stock of railways. Analytical, diagnostic and didactic methods, theory and methodology of design and mechanics of freight wagon, theory of complex systems, systems engineering, modeling, as well as methodological tools for organizing experiments were used. The scientific novelty is the constructive and technological scheme of a specialized laboratory stand; a didactic set of materials for organizing laboratory work using this stand.It has been established that the introduction of a new rolling stock with an increased carrying capacity is the main trend of modern car building and should be accompanied by appropriate training of highly qualified specialists capable of further development of new generation freight wagons. It is noted that conducting educational and research sessions involves studying not only the problems of strength, but also acquiring skills in working with digital technologies for collecting and transmitting data. A detailed description is given of a specialized stand developed at the Department of "Wagons and Carriage Facilities" of PGUPS for studying the properties of dynamics and strength of freight wagons of the laboratory stand. In particular, the device of the base trolley model 18-9855 is shown, the technology of the stand operation is described, illustrative materials are given on the structure and principle of operation of the projected stand. For practical laboratory exercises, a typical version of laboratory work with the use of this stand is proposed. It is shown that the involvement of students in the implementation of practical experiments and applied bench research increases interest in the future profession and allows the formation of strong skills in practical diagnostics of the current state of a freight wagon.

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Mawdsley, Evan. "Book Review: The Viaz’ma Catastrophe, 1941: The Red Army’s Disastrous Stand against Operation Typhoon by Lev Lopukhovsky and Operation Typhoon: Hitler’s March on Moscow, October 1941 by David Stahel." War in History 21, no. 3 (June 4, 2014): 389–91. http://dx.doi.org/10.1177/0968344514526634h.

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Kamiński, Mariusz, Piotr Budzyński, Jacek Hunicz, and Jerzy Józwik. "Evaluation of changes in fuel delivery rate by electromagnetic injectors in a common rail system during simulated operation." Eksploatacja i Niezawodnosc - Maintenance and Reliability 23, no. 2 (March 22, 2021): 352–58. http://dx.doi.org/10.17531/ein.2021.2.15.

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The objective of this study was to determine changes in fuel delivery rate by common rail system injectors during their simulated operation on a test stand. Four Bosch injectors used, among others, in Fiat 1.3 Multijet engines were tested. The injectors were operated on a test rig at room temperature for 500 hours (more than 72 million work cycles). During the test, pressure and injection frequency were changed. Changes in the operating parameters were estimated based on obtained injection characteristics and effective flow area determined thereby. The observed changes in fuel delivery rate were compared with results of the surface analysis of control valves and nozzle needles. Despite the stated lack of wear, significant changes in the dynamics of injector operation were observed, particularly at short injection times. Small pilot injections do not have to be corrected by the fuel injection control system because they do not affect the changes in torque; however, they do affect the combustion process. This creates conditions for increased emission of toxic exhaust components.

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CHENG, CHING-CHING, MING-SHING YOUNG, SHANG-WEN YOUNG, and CHANG-LIN CHUANG. "AN INTELLIGENT DIGITAL VOLTAMMETRIC SYSTEM WITH MULTIPLE FUNCTIONS EXECUTED THROUGH STAND-ALONE OPERATION OR PC-CONTROL." Biomedical Engineering: Applications, Basis and Communications 14, no. 05 (October 25, 2002): 218–36. http://dx.doi.org/10.4015/s1016237202000322.

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This study presents an intelligent voltammetric system consisting of a personal computer and a digital voltammeter with VXIbus architecture of system control board, voltammetric measurement board and electrode evaluation board. System is designed to provide superior, comprehensive, versatile and convenient storage, analysis and display of electrochemical and voltammetric waveforms. Voltammeter is capable of stand-alone operation or direct PC control through a Labview program and serial communication interface. Stand-alone offers several general voltammetric functions such as electrochemical treatment and evaluation of electrodes and experimental voltammetry. PC connection gives additional functions such as automatic scanning of oxidation potential, expanded storage and processing of experimental data, arbitrary voltammetric waveform parameters, etc. Standalone uses microcontroller and three-bus structure, with EEPROM storing waveform parameters, experimental data and machine code program downloaded from PC. Electrode evaluation board tests electrode quality by measuring electrode equivalent resistance and capacitance, requiring only one button to perform the entire procedure. Minimum potential unit is 1 mV, at which setting the voltage range is −2.05 to +2.05 V. At a minimum unit of 4.9 mV, the voltage range is −10 to +10V. Experimental results are presented using carbon fiber electrode to measure the dopamine concentration in PBS solution, showing minimum oxidation current can be measured to less than 10 pA, with a minimum detectable bulk concentration of less than 10 ppb. The combination of PC with stand-alone voltammeter offers high-speed, precision, automation, versatility and portability, while the VXIbus architecture allows easy expansion capability.

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Journal articles on the topic 'Stand-by operation'

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