Journal articles: 'Tool turret'

1

Dai, Yuan Xing, Tian Rui Zhang, Xue Wei Zhang, and Tian Biao Yu. "Kinematics and Dynamics Simulation of a New Type Direct-Drive NC Turret Tool Post." Applied Mechanics and Materials 325-326 (June 2013): 247–51. http://dx.doi.org/10.4028/www.scientific.net/amm.325-326.247.

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Building 3D model for a new type direct-drive NC Turret tool post, and introduce the model into ADAMS for further kinematics and dynamics simulation. In the kinematics simulation, observing the motion process of the direct-drive NC turret tool post and plots the trajectory of moving parts to a curve. Simulate the force condition of the NC turret tool post in actual situation, calculate the axial load and verify the clamping force in dynamics simulation.

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Arsecularatne, J. A., and P. Mathew. "An Optimal Tool Replacement Strategy for Computer Numerical Controlled Turning Centres." Proceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture 209, no. 6 (December 1995): 481–90. http://dx.doi.org/10.1243/pime_proc_1995_209_112_02.

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For a computer numerical controlled (CNC) turning centre with a multi-station tool turret, this paper describes a tool replacement strategy for tools used for both rough and finish turning, boring and facing operations as well as other end operations which include drilling, grooving, threading and parting-off. The method ensures a convenient replacement strategy where tools in the machine turret are replaced after machining integer multiples of an optimum number of components. This optimum number of components is determined so that the total cost due to tools and tool changing time is minimized. An example is given to illustrate how the procedure determines the optimal tool replacement strategy. It shows that the described method can substantially reduce the number of interruptions due to tool replacements in processing a batch.

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Sun, Shu Xia, Xiang Jun Zhu, and Ming Ming Wang. "Power Turret the Dynamics Simulation Analysis of Power Turret." Applied Mechanics and Materials 198-199 (September 2012): 133–36. http://dx.doi.org/10.4028/www.scientific.net/amm.198-199.133.

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The dynamic performance of the CNC turret affect the cutting capability and cutting efficiency of the NC machine tool directly, embody the core level of the design and manufacture of the NC machine tool. However, the dynamic performance of the CNC turret mostly decided by the dynamic performance of the power transmission system of the power turret. This passage use Pro/E to set the accurate model of the gears and the CAD model of the gear transmission system and based on this to constitute the ADAMS model of virtual prototype. On the many-body contact dynamics theory basis, dynamic describes the process of the mesh of the gears, work out the dynamic meshing force under the given input rotating speed and loading, and the vibration response of the gear system. The simulation result disclosure the meshing shock excitation and periodical fluctuation phenomena arose by stiffness excitation of the gear transmission. Analyses and pick-up the radial vibration response of the output gear of the gear transmission system as the feasibility analysis data.

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Adesta, Erry Yulian Triblas, and Muataz H. F. Al Hazza. "Machining Time Simulation in High Speed Hard Turning." Advanced Materials Research 264-265 (June 2011): 1102–6. http://dx.doi.org/10.4028/www.scientific.net/amr.264-265.1102.

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High speed hard turning is an advanced manufacturing technology that reduces the machining time because of two reasons; reducing the manufacturing steps and increasing the cutting speed. This new approach needs an economical justification; one of the main economical factors is the machining time. The machining time was breaking down into three main parts; productive time, non productive time, and preparation time. By using matlab Simulink, a new program was developed for machining time allowing the manufacturer to find rapidly the values of cutting time parameters and gives the management the opportunity to modify the processing parameters to achieve the optimum time by using the optimum cutting parameters. Table 1: Nomenclature d Depth of cut M T total machining time pmv t Total movement time D Work piece diameter h t handling time pch t Total Tool changing time f Feed rate tc t tool changing time pre t Total preparing time z e Engagement distance on Z-axis ch t Tool changing time per piece, prg t Programming time x e Degagement distance on X-axis am t Machine allowance time su t Set up time k Number of passes ao t Operator allowance time sum t Machine set up L Tool life a t Allowance time sut t Tool set up l Work piece length o t Tool movement at the rapid speed suw t Work piece set up N Spindle speed oA t From zero point to cutting point TH Tool hardness tool n No. of tool posts in the turret p t Total productive time o X tidy of the O t point o1 p Initial position of the turret. o Z = abciss of the O t point w Work piece weigh o2 p Position of the used tool c V Cutting speed c w Width of cutting speed r Rotation speed of the turret f V Feeding speed tool n no. of tool in the turret c t Cutting time o V Rapid speed speed r : Turret rotation speed

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Wang, Yu Sheng, Ming Ming Wang, and Xiang Jun Zhu. "Research on Speed Changing Curve of Servo Turret Motor." Applied Mechanics and Materials 198-199 (September 2012): 137–40. http://dx.doi.org/10.4028/www.scientific.net/amm.198-199.137.

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Because of such merits of servo turret like fast speed of tool changing, high accuracy of first location, simple mechanical structure, high reliability and so on, servo turrets are widely used in turning processing and turning and milling complex processing center.Control mode of servo motor speed is one of the critical problems in the designing of servo turret.S curve acceleration and deceleration control is to make the derivative of acceleration as constant in this procession, and maximize to reduce the impact of mechanical system by controlling acceleration derivative. Otherwise, by setting parameter or programming acceleration and its derivative, flexible acceleration and deceleration will be controlled to fit for different kinds of situation of machines.

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Zhang, Er Hong, and Hua Long Zhang. "Study on Surface Processing of Non-Rotational Symmetry." Advanced Materials Research 1094 (March 2015): 348–51. http://dx.doi.org/10.4028/www.scientific.net/amr.1094.348.

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This paper studies on technology of slow tool servo method and the processing of high efficiency. High precision surface NRS goal is studied for factors affecting theNRSworkability and surface machining accuracy. Including slow tool servo theory, research tools, tool path generation, surface microstructure simulation, slow tool servoNRSsurface machining and simulation systems development, installation errors and adjustment tool,Yto linear turret design,NRSsurface machining experiments.

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Liu, Le Ping, Ya Jun Yan, Yu An Peng, Hai Dong Li, and Qi Zheng Dong. "Structure Analysis and Optimization of Hydraulic Tool Turret Cabinet of CNC Lathe." Advanced Materials Research 945-949 (June 2014): 498–502. http://dx.doi.org/10.4028/www.scientific.net/amr.945-949.498.

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The research object is hydraulic tool turret cabinet of CNC lathe. Building the hydraulic tool turret cabinet model by Pro/E, then meshing the cabinet by Hyper-mesh software, finally calculating by the ANSYS. Do modal analysis and harmonic response analysis for the cabinet, then make the second order frequency maximum as a target, use the Altair OptiStruct to improve its dynamic structure. The result shows: though the quality of optimized body is increased, but it avoids the resonance frequency, which greatly reduce the possibility of resonance, and greatly improve the dynamic performance of the cabinet.

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Herwan, Jonny, Seisuke Kano, Ryabov Oleg, Hiroyuki Sawada, and Masahiro Watanabe. "Comparing Vibration Sensor Positions in CNC Turning for a Feasible Application in Smart Manufacturing System." International Journal of Automation Technology 12, no. 3 (May 1, 2018): 282–89. http://dx.doi.org/10.20965/ijat.2018.p0282.

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Tool condition monitoring, such as tool wear and breakage, is an essential feature in smart manufacturing system. One of most potential sensors that can be used in tool monitoring is vibration sensor, which usually assembled at tool shank. However, in case of CNC turning with rotating tool turret, it is impossible to assemble the vibration sensor at the tool shank because wire of the sensor will be damaged when the turret rotated. This paper is addressed to compare thoroughly alternative sensor positions. Ten sensor positions including tool shank, as a reference, are investigated. The signals from three types of cutting, namely; normal cutting, abnormal cutting with tool wear and abnormal cutting when tool breakage occurred, are investigated. Based on the magnitude of the output signals and their capability to predict tool wear and breakage, a suggestion on vibration sensor positions is proposed.

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9

Chen, C.-G., and S.-T. Chiou. "Surface design of roller gear cam mechanisms with a turret in both translation and rotation." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 222, no. 6 (June 1, 2008): 1071–80. http://dx.doi.org/10.1243/09544062jmes855.

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Roller gear cam mechanisms (RGCMs) are used extensively as automatic tool changers of machining centres or as indexing mechanisms in various machinery. However, almost all the existing RGCMs have a turret in a rotational motion only. Thus for example, when they are used as a part of automatic tool changers, the translational motions of the tools have to be given by other mechanisms. An RGCM with a turret which can move with both translation and rotation simultaneously is proposed; such an RGCM may simplify the structure of some machines. By using D-H homogeneous coordinate transformation matrices, and applying the theory of conjugate surfaces, the model for the surface design of the RGCM is developed. Two examples are included to demonstrate the usages of the model and to verify its correctness.

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10

Tsay, Der Min, and Bor Jeng Lin. "Design and Machining of Globoidal Index Cams." Journal of Manufacturing Science and Engineering 119, no. 1 (February 1, 1997): 21–29. http://dx.doi.org/10.1115/1.2836552.

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A simple, yet useful approach to the geometry design and machining of globoidal index cams and roller-follower turrets is developed. From the machining point of view of the globoidal cam by an end mill, the side surface geometry can be easily defined as the swept surface by the tool path. By using the analytical cam surface formulation, the pressure angle, the contact forces, and the torques between the cam and the turret can be investigated. In the machining process, to avoid undercutting, principal curvatures are analyzed. To demonstrate the usefulness and effectiveness of the procedure, two numerical examples of the globoidal index cams are presented along with the 3D computer printouts and the photography of machined samples.

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11

Changyou, Li, Wang Wei, Zhang Yimin, Guo Song, Li Zhenyuan, and Qiao Changshuai. "Indexing accuracy reliability sensitivity analysis of power tool turret." Eksploatacja i Niezawodnosc - Maintenance and Reliability 17, no. 1 (January 1, 2015): 27–34. http://dx.doi.org/10.17531/ein.2015.1.4.

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12

Cho, Kyung Ho, and Kunwoo Lee. "Automatic Tool Selection for NC Turret Operation in Sheet Metal Stamping." Journal of Engineering for Industry 116, no. 2 (May 1, 1994): 239–46. http://dx.doi.org/10.1115/1.2901936.

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In sheet metal fabrication using an NCT (numerically controlled turret punch press) machine, automatic tool selection is a major problem to be solved to improve its production performance. However, this operation has been done either manually or semi-automatically by human experts. In this paper, we have introduced the shape-index-set to handle the shape of sheet metal parts and developed an algorithm through which one can find the successive matching curves between two curve lists, one from the punching tool and the other from the boundaries of the sheet metal part. The algorithm is used to select the tools automatically to punch out the boundaries of sheet metal parts. Several experiments are presented to prove the successful tool selection.

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13

Zhou, Shi Peng, Yun Zhao, Feng Li Huang, and Hua Jie Li. "Dynamics Simulation on Rigid-Flexible Coupled Sliding Guideways in Powered Tool Turret of NC Lathe." Applied Mechanics and Materials 201-202 (October 2012): 181–84. http://dx.doi.org/10.4028/www.scientific.net/amm.201-202.181.

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A rigid-flexible coupling model of sliding guideway working in powered turret for a new developed multifunction NC lathe is built up based on Solidworks, ANSYS and ADAMS. A solid model of is built up by the 3d-Modeling software Solidworks, and then the built model of sliding guideway is imported into finite element analysis software ANSYS to analyze elastic deformation. A mnf file of model generated by ANSYS which is a flexible body is fed into ADAMS to replace the rigid body of assembly. A dynamics simulation is conducted by considering a typical cutting processing like milling on lathe, the deformation of fixed guideway in working condition is checked. The analyzed results show that it is more rational and accurate to apply rigid-flexible coupling dynamic simulation for analyzing such mechanical system and this type of sliding guideway used in powered tool turret can stand up with cutting load and can meet the requirement.

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14

Wang, San Wu, Jiang Wu, Yao Deng Fan, Shou Ma, and Xi Bin Gong. "Crankshaft Composite Lathe’s Tool Tip Trajectory Error Analysis and Simulation." Advanced Materials Research 823 (October 2013): 199–204. http://dx.doi.org/10.4028/www.scientific.net/amr.823.199.

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The crankshaft composite follow crankshaft turning lathes use the following tool system to complete the turning of crankshaft, when crankshaft machining is working, the turret mechanisms processing error and assembly errors will affect the crankshafts processing quality, So it is difficult to control the actual machining accuracy, or it may cause the waste of material. Therefore, in this paper, by analyzing the impact of the rod length errors on the trajectory of the tool tip, the tool tip trajectorys equations can be built. Using MATLAB tools, we can build the tip point trajectory modeling and solve the deviation between the actual tip point and the ideal trajectory, and finally can get the result of rod lengths error on the accuracy of the actual processing, which will provide basis for the design and analysis in future.

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15

Zhu, Li-sha, Lian-sheng Li, Shang-jie Li, and Shan Wang. "Research on Reliability for Servo Turret Based on Vibration Transmission Path System with Stiffness Degradation Model." Mathematical Problems in Engineering 2020 (November 3, 2020): 1–11. http://dx.doi.org/10.1155/2020/3764546.

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The stiffness degradation of the servo turret will inevitably lead to accuracy reduction of the cutter head and the tool change. Considering the degradation process of servo turret with stiffness, by introducing the stiffness cumulative damage theory into the vibration differential equation, combined with stochastic finite element method and reliability theory, the mathematical model of the reliability and reliability sensitivity for vibration transmission path system with random parameters was established. Taking a typical power servo turret for example, the reliability and the reliability sensitivity to each random parameter at the mean value with the excitation frequency and time were obtained. The results showed that the shift of the reliability and reliability sensitivity to random parameters with time was caused by the stiffness degradation, the peak value of reliability sensitivity fluctuated with time, and the peak value in the frequency domain at the initial time was not necessarily the maximum value in the time domain. The accuracy of the proposed method was further proved by the Monte Carlo method. Optimizing sensitive parameters could enhance the system stability and effectively prevent the resonance failure caused by the change of the resonance region.

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Kaldashev, Tsvetan. "DEVELOPMENT OF A POSTPROCESSOR FOR TURNING CENTER AND MULTI-TASK MACHINE WITH MULTI-CHANNEL CNC SYSTEMS." Proceedings of CBU in Natural Sciences and ICT 1 (November 16, 2020): 28–32. http://dx.doi.org/10.12955/pns.v1.117.

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This article discusses the possibility of developing a postprocessor for turning center with 2 turrets and a multi-channel CNC system with NC program format characteristic of machine Mazak Integrex I series. Typical for these CNCs is the usage of two support programs - one for each turret. The CAD / CAM system PTC Creo is used to solve the problem, where tool transitions are developed for machining the workpieces. The postprocessor is software that translates the CL Data file i.e. turns it into a NC program with preparatory, technological, and supplementary commands to control the machine. G-POST, which is integrated into the PTC Creo CAD / CAM system, is used to develop the post-processor. To solve the problem, a specialized programming language FIL (Factory Interface Language) is used which, with its features and capabilities to work with files in ASCII code, achieves the ultimate goal - NC program in format characteristics suitable for machines Mazak Integrex I series.

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17

Du, Yi Gang, Wen Zhi Zhang, Ying Han Liu, and Zhao Hui Jin. "System Design of Numerical Control Turret Press Based on Motion Controller." Advanced Materials Research 655-657 (January 2013): 1317–20. http://dx.doi.org/10.4028/www.scientific.net/amr.655-657.1317.

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According to the characteristics and requirements of NCT processing system, deeper research was done on the system. The three-module design has been completed based on motion controller. The first module is completed on the design of panel, key position, machine functions and coding circuit; the second module is mainly accomplished on the tool-path generation, tool adapter and program development; the last module is used to verify the NC codes. Thus the NCT processing system is improved effectively.

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Milne, I. A., S. Delaux, and P. McComb. "Validation of a predictive tool for the heading of turret-moored vessels." Ocean Engineering 128 (December 2016): 22–40. http://dx.doi.org/10.1016/j.oceaneng.2016.10.007.

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Pini, B. E., Yu V. Maksimov, and A. V. Popov. "Turret head for numerically controlled machine tools with a pneumatic rotary drive for the tool disk." Russian Engineering Research 36, no. 5 (May 2016): 383–85. http://dx.doi.org/10.3103/s1068798x1605018x.

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20

Zhang, Shuai, and Xue Fang Du. "The Simulation of the Real-Time Adjustment of Cutting Edge Inclination of CNC Turret." Advanced Materials Research 889-890 (February 2014): 542–45. http://dx.doi.org/10.4028/www.scientific.net/amr.889-890.542.

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In turning process, one of the effective ways to obtain the best cutting characteristics is the real-time adjustment tool cutting edge inclination. This paper designs a real-time adjustment tool cutting edge inclination of the head; the motion analysis by software, the tool structure is optimized further, so that in the premise of turning accuracy, can be adjusted real time tool cutting edge inclination.

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Tsay, D. M., H. P. Chen, and S. Y. Lin. "A direct method for determining meshing surfaces of globoidal cams with tapered roller followers." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 223, no. 7 (March 30, 2009): 1667–76. http://dx.doi.org/10.1243/09544062jmes1331.

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For determining the globoidal cam profile with tapered rollers radially mounted at its turret, a direct and relative simple approach is presented. The concept of the proposed procedure is based on the cam surfaces that can be represented as the swept surfaces of the tapered roller of the globoidal cam-turret mechanism in motion. For finding the swept surfaces of the tapered roller, the pitch surface yielded by the locus of the tapered roller is first generated through the rigid body transformation. Then, in the process of producing the swept surfaces for the cam surfaces, the meshing angles and meshing vectors are defined and identified by using the pitch surface of the tapered roller. Since it is not necessary to solve any non-linear contact equations usually encountered in traditional methods, such a procedure provides a convenient tool in determining the spatial cam surfaces. To demonstrate the feasibility and accuracy of the proposed approach, its analytical formulations with numerical results are compared with those obtained by an earlier technique based on the theory of screws.

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Tangjitsitcharoen, Somkiat, and Suthas Ratanakuakangwan. "Monitoring of Cutting Conditions with Dry Cutting on CNC Turning Machine." Key Engineering Materials 443 (June 2010): 382–87. http://dx.doi.org/10.4028/www.scientific.net/kem.443.382.

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This paper presents the additional work of the previous research in order to verify the previously obtained cutting condition by using the different cutting tool geometries. The effects of the cutting conditions with the dry cutting are monitored to obtain the proper cutting condition for the plain carbon steel with the coated carbide tool based on the consideration of the surface roughness and the tool life. The dynamometer is employed and installed on the turret of CNC turning machine to measure the in-process cutting forces. The in-process cutting forces are used to analyze the cutting temperature, the tool wear and the surface roughness. The experimentally obtained results show that the surface roughness and the tool wear can be well explained by the in-process cutting forces. Referring to the criteria, the experimentally obtained proper cutting condition is the same with the previous research except the rake angle and the tool nose radius.

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Renn, Jyh Chyang, Wen Jen Hsu, and Yun Ruei Li. "Constant Pressure Control for Energy Efficient Lathe Turret." Key Engineering Materials 661 (September 2015): 3–9. http://dx.doi.org/10.4028/www.scientific.net/kem.661.3.

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Hydraulic system plays an important role in many power systems such as excavator, braking system of vehicle and machine tool. Generally speaking, hydraulic control system can be divided into two different driving concepts. The first one is the well-known valve-controlled system and the second one is the pump-controlled system. The former possesses the feature of fast dynamic response. However, the poor energy-saving performance is its major fault. On the contrary, the pump-controlled system has the significant advantage of energy-saving which meets the current demand in modern machine design, but has the disadvantage of slower dynamic response. With the advancement of electric-motor system, however, this disadvantage has been greatly improved. In this paper, the simulation analysis of a newly developed energy-efficient hydraulic CNC lathe turret based on constant pressure control scheme is presented. Instead of the conventional fixed displacement hydraulic pump, the new energy-efficient system utilizes an internal gear pump together with an AC servo motor as its driving power source. In addition, a closed-loop control scheme using PID control is adopted. From simulation results, the new energy-efficient design can reduce the waste of the output flow-rate of the pump through the relief valve that generally happens in conventional hydraulic lathe and then achieve the purpose of designing an energy-efficient hydraulic lathe.

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Herwan, Jonny, Seisuke Kano, Oleg Ryabov, Hiroyuki Sawada, Nagayoshi Kasashima, and Takashi Misaka. "Predicting Surface Roughness of Dry Cut Grey Cast Iron Based on Cutting Parameters and Vibration Signals from Different Sensor Positions in CNC Turning." International Journal of Automation Technology 14, no. 2 (March 5, 2020): 217–28. http://dx.doi.org/10.20965/ijat.2020.p0217.

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During the turning process, cast iron is directly shattered to become particles. This mechanism means the surface roughness cannot be predicted using the kinematic equation. This paper provides surface roughness predictions using two methods, the multiple regression model (MRM) and artificial neural network (ANN). Cutting parameters and vibration signals are considered input variables in both methods. This work also overcomes the common sensor position limitation (tool shank) and provides a safe and efficient solution. The prediction values from MRM and ANN show accurate results compared to the measured surface roughness, with the average error of less than 8%. Furthermore, the proposed sensor position, at the turret bed, also exhibits similar prediction accuracy to a sensor at the tool shank, hence promising feasible industrial application.

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Chanthana, Deuanphan, and Somkiat Tangjitsitcharoen. "A Study of Relation between Roundness and Cutting Force in CNC Turning Process." Applied Mechanics and Materials 799-800 (October 2015): 366–71. http://dx.doi.org/10.4028/www.scientific.net/amm.799-800.366.

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The roundness is one of the most important criteria to accept the mechanical parts in the CNC turning process. The relations of the roundness, the cutting conditions and the cutting forces in CNC turning is hence studied in this research. The dynamometer is installed on the turret of the CNC turning machine to measure the in-process cutting force signals. The cutting parameters are investigated to analyze the effects of them on the roundness which are the cutting speed, the feed rate, the depth of cut, the tool nose radius and the rake angle. The experimentally obtained results showed that the better roundness is obtained with an increase in cutting speed, tool nose radius and rake angle. The relation between the cutting parameters and the roundness can be explained by the in-process cutting forces. It is understood that the roundness can be monitored by using the in-process cutting forces.

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Minis, I. E., E. B. Magrab, and I. O. Pandelidis. "Improved Methods for the Prediction of Chatter in Turning, Part 2: Determination of Cutting Process Parameters." Journal of Engineering for Industry 112, no. 1 (February 1, 1990): 21–27. http://dx.doi.org/10.1115/1.2899291.

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The dynamics of the metal cutting process are identified by a new and simple experimental method that permits the direct determination of the cutting transfer functions from input-output measurements. A specially designed stiff force dynamometer rigidly mounted to the machine tool’s turret is used for the measurement of the cutting force. An external force is applied to the base plate of the dynamometer in such a way that the meaurements of both the tool’s displacement and the corresponding cutting force are uncoupled from the influence of the machine tool structure’s dynamics. The cutting transfer functions are obtained in the vicinity of the structure’s first resonance, under a wide range of cutting conditions.

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Shawky, A. M., and M. A. Elbestawi. "Model-Based Predictive Control of Workpiece Accuracy in Bar Turning." Journal of Manufacturing Science and Engineering 120, no. 1 (February 1, 1998): 57–67. http://dx.doi.org/10.1115/1.2830111.

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In this paper a real-time model-based geometric control system is proposed for workpiece accuracy in bar turning. An on-line ultrasonic measurement system that operates in the presence of cutting fluid is employed for workpiece diameter measurement. A state space mechanistic model is used to overcome the delay in the feedback loop. A Kalman Filter is used in a predictor-corrector fashion to update model predictions using on-line measurements. A full state feedback controller with an integral control action is designed and used to manipulate the tool position in real-time for machining error compensation. The performance of the proposed control strategy is evaluated through cutting experiments performed on a CNC turret lathe retrofitted with an open architecture controller.

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Jiang, Ke He, Bei Bei Sun, and Xiao Bo Kang. "Simulations of Thermal Behaviors on a Power-Driven Turret." Advanced Materials Research 139-141 (October 2010): 961–64. http://dx.doi.org/10.4028/www.scientific.net/amr.139-141.961.

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As core functional components of the medium and high grade CNC machine tools, the power-driven turret involves high technology and complicated structures. Traditionally, in the study of low speed turrets` performances, the effects of thermal influences are often negligible. However, on the high speed conditions, thermal effect cannot be neglected. This paper establishes the high speed turret 3-D Model and the Finite Element Model (FEM), and investigates and analyzes temperature fields and thermal deformations. Experimental measurements are implemented on the surfaces of the original model turret in order to compare with the simulation results, modified turret is analyzed, and thermal behaviors are proved to be available on the idle operating conditions. It manifests that the distributions of the thermal behaviors have intensive relations with the speeds of the transmission system.

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Pelic, Marcin, Bartosz Gapiński, and Wojciech Ptaszyński. "Application of Piezoelectric Fast Tool Servo for Turning Non-Circular Shapes Made of 6082 Aluminum Alloy." Applied Sciences 11, no. 16 (August 17, 2021): 7533. http://dx.doi.org/10.3390/app11167533.

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The paper presents the design and testing of a new servo drive for turning non-circular shapes. The presented solution is based on a commercially available piezoelectric drive unit with a stroke equal to 1000 µm and a resonant frequency of 150 Hz. The device was used in a conventional turning lathe and installed in a tool turret. The performance of the proposed tool was tested while turning multiple non-circular contours from a cylindrical shaft made of 6082 aluminum alloy. The machining accuracy was tested online using a laser sensor and offline with a coordinate measuring machine. The additional aim of those tests was also to verify if the application of an online transducer can allow a confident preliminary assessment of as-machined geometry. The drive positioning accuracy was compensated using 6th order polynomial what resulted in the fabrication of non-circular contours with an accuracy of no less than 39.8 µm when operating below the limit frequency of the drive (<9 Hz). It was found out that the deviations of the profile from ideal geometries increase linearly with frequency when turning at higher than the limit frequency.

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Verma, Kuldeep, R. M. Belokar, Vinod Kumar Verma, and Klimis Ntalianis. "Track-based analysis for profile generation on globoidal cam in automatic tool changer of CNC machining center." Assembly Automation 39, no. 2 (April 1, 2019): 369–79. http://dx.doi.org/10.1108/aa-08-2018-111.

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PurposeThis paper aims to propose an elementary approach towards the measurement of a globoidal cam profile used in an automatic tool changer (ATC) of computer numerical control (CNC) machines.Design/methodology/approachA simple and unique online method has been designed for the profile metrology of the cam. This simple methodology will replace the traditional methodology of profile metrology of cam by coordinate measuring machine (CMM). A globoidal cam with an indexable turret and roller follower (rotating in an enclosed track) has been evaluated in our analysis. This analysis plays a significant role in the performance determination of the cam as well as the ATC of CNC machines.FindingsA novel model has been designed and implemented to investigate the profile of a globoidal cam. The proposed methodology becomes an enhancement over the old methodology, i.e. measurement through CMM. Theoretical analysis and practical implementation prove the significance of the method.Originality/valueAn enhanced methodology to effectively measure the globoidal cam profile has been proposed. The practical implication of the proposed methodology remains for the CNC machine tool and ATC manufacturers. Finally, analytical explorations have been carried out to prove the validity of the proposal.

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Nakanishi, Kenichi, Manabu Sawada, and Jiro Sakamoto. "Influence of Heat in Multi-Tasking Machine Bed and its Analytical Technique." International Journal of Automation Technology 12, no. 2 (March 1, 2018): 254–61. http://dx.doi.org/10.20965/ijat.2018.p0254.

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When designing a large-sized cast product for a multi-spindled machine tool, such as a multi-turret type multi-tasking machine, we must first determine its thermal deformations by the finite element method (FEM) in order to ensure that the structure is designed with high thermal rigidity. Casting technology has progressed so much that we can now form more complicated internal structures and produce much thinner and lighter cast products. Moreover, since designing cast products has become much faster, higher-efficiency analytical techniques are also required. Such analytical techniques are operated by designers where analyses and design are executed interchangeably. In this study, we compared the experimental results to the analytical results in order to evaluate the employed analytical technique based on an actual analysis of a multi-tasking machine bed with a few different rib structures.

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Li, X. M., Ya Lin Shen, and L. H. Zhu. "Research and Development of CA6140 Virtual Assembly System." Key Engineering Materials 621 (August 2014): 558–63. http://dx.doi.org/10.4028/www.scientific.net/kem.621.558.

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On the basis of analyzing assembly process of main structural components in CA6140 lathe, 3D models for those components were established with CAD software UGNX6.0. Virtual assembly and motion simulation of the structure parts were performed with virtual technology. A set of virtual assembly system of CA6140 engine lathe was developed with programming software Visual Basic 6.0. It contains six main modules about spindle box, feed box, apron, tailstock, turret, etc. Dynamic simulation and motion simulation of the corresponding components in entity lathe can be realized, respectively. And also, mechanical structure, working principle, assembly relation between different components and motion transmission process of the lathe can be realistically reproduced with the system. This virtual assembly system not only can be used to analyze and transform old products, but also can be used in new products development, and to some extent, can be used to replace the prototype. It is an indispensable tool in the employee training and mechanical engineering activities.

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Tangjitsitcharoen, Somkiat. "Prediction of Surface Roughness on CNC Turning Based on Monitoring of Cutting Force and Cutting Temperature." Advanced Materials Research 690-693 (May 2013): 2540–49. http://dx.doi.org/10.4028/www.scientific.net/amr.690-693.2540.

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This paper presents the surface roughness model which is proposed and developed to predict the surface roughness in the CNC turning of the carbon steel with the coated carbide tool under various cutting conditions by using the response surface analysis with the Box-Behnken design based on the experimental results. The in-process monitoring of the cutting force and the cutting temperature is utilized to analyze the relation between the surface roughness and the cutting condition. The tool dynamometer and the infrared pyrometer are employed and installed on the turret of CNC turning machine to measure the in-process cutting force and cutting temperature. The models of cutting force ratio and cutting temperature are also developed based on the experimental data. The optimum cutting condition is determined referring to the minimum surface roughness of the surface plot, which is obtained from the developed surface roughness model. The experimental results show that the higher cutting speed gives the better surface roughness due to the higher cutting temperature, however the tool life becomes shorter. The feed rate is the most significant factor which affects the surface roughness, while a small depth of cut helps to improve the surface roughness. The effectiveness of the surface roughness prediction model has been proved by utilizing an analysis of variance (ANOVA) at 95% confident level. Hence, the surface roughness can be predicted and obtained easily referring to the developed surface roughness model.

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Angulo, Ángela, Jialin Tang, Ali Khadimallah, Slim Soua, Cristinel Mares, and Tat-Hean Gan. "Acoustic Emission Monitoring of Fatigue Crack Growth in Mooring Chains." Applied Sciences 9, no. 11 (May 28, 2019): 2187. http://dx.doi.org/10.3390/app9112187.

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Offshore installations are subject to perpetual fatigue loading and are usually very hard to inspect. Close visual inspection from the turret is usually too hazardous for divers and is not possible with remotely operated vehicles (ROVs) because of the limited access. Conventional nondestructive techniques (NDTs) have been used in the past to carry out inspections of mooring chains, floating production storage and offloading systems (FPSOs), and other platforms. Although these have been successful at detecting and assessing fatigue cracks, the hazardous nature of the operations calls for remote techniques that could be applied continuously to identify damage initiation and progress. The aim of the present work is to study the capabilities of acoustic emission (AE) as a monitoring tool to detect fatigue crack initiation and propagation in mooring chains. A 72-day large-scale experiment was designed for this purpose. A detailed analysis of the different AE signal time domain features was not conclusive, possibly due to the high level of noise. However, the frequency content of the AE signals offers a promising indication of fatigue crack growth.

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Shansungnoen, Thararath, and Somkiat Tangjitsitcharoen. "Investigation of Relation between Straightness and Cutting Force in CNC Turning Process." Applied Mechanics and Materials 789-790 (September 2015): 812–20. http://dx.doi.org/10.4028/www.scientific.net/amm.789-790.812.

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The objective of this research is to examine the relation between the straightness and the cutting force ratio during the CNC turning process. The cutting force is monitored and obtained by installing the dynamometer on the turret of CNC turning machine. The relation between the cutting force ratio and the straightness is investigated under the various cutting conditions, which are the cutting speed, the feed rate, the depth of cut, the tool nose radius and the rake angle. The experimentally obtained results showed that the straightness can be improved with an increase in cutting speed, tool nose radius and rake angle. The relation between the dynamic cutting force and straightness profile can be proved by checking the frequency of the cutting force in frequency domain with the use of the Fast Fourier Transform (FFT), which is the same as the straightness profile. Hence, the cutting force ratio can be used to predict the straightness during the cutting regardless of the cutting conditions. The cutting force ratio is proposed to predict the straightness during turning process by employing the exponential function for the sake of straightness. The multiple regression analysis has been utilized to calculate the regression coefficients of the in-process prediction of straightness model by using the least square method at 95% confident level. It has been proved by the cutting tests that the in-process straightness can be predicted during the cutting within ±10% measured straightness with the high accuracy of 91.85%.

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She, Chen Hua, Jian Yu Lin, and Shen Yung Lin. "Numerical Control Programming System for Mill-Turn Machining." Applied Mechanics and Materials 799-800 (October 2015): 1154–57. http://dx.doi.org/10.4028/www.scientific.net/amm.799-800.1154.

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To develop the numerical control program of mill-turn machine, the traditional method is to apply the computer-aided design and manufacture software to construct the geometric model, then to generate tool path and convert the path to NC program. For complex numerical control program of mill-turn machine, such as the multiple turret synchronized motion machining, because of the need to control time sequence, the NC program is highly required on using of dedicated software system. The objective of this paper is to establish a mill-turn machining system with window interface of via the language of Borland C++ Builder. The developed system can plan the machining path of simple mill-turn features, including turning shape, axial slot milling, and radial packet milling, and generate the corresponding NC program. For the milling functions, after the offset coordinates are calculated along the polygonal angle vector in the center point of cutters, the NC program is generated. For the turning functions, through importing the 2D DXF (Drawing Exchange Format) file and inputting related configurations, the entity coordinates can be retrieved and the corresponding NC program is then converted. By means of the solid cutting simulation software and practical cutting experiment for the generated numerical control program, the accuracy of the tool path generation algorithm is confirmed. Hence, the cost of purchasing commercial software can be saved and the time of generating program can also be decreased so that the working efficiency can be enhanced.

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Zhao, Yonghui, Zongyun Chen, Zhijian Cao, Wenxin Li, and Yingliang Wu. "Diverse Structural Features of Potassium Channels Characterized by Scorpion Toxins as Molecular Probes." Molecules 24, no. 11 (May 29, 2019): 2045. http://dx.doi.org/10.3390/molecules24112045.

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Scorpion toxins are well-known as the largest potassium channel peptide blocker family. They have been successfully proven to be valuable molecular probes for structural research on diverse potassium channels. The potassium channel pore region, including the turret and filter regions, is the binding interface for scorpion toxins, and structural features from different potassium channels have been identified using different scorpion toxins. According to the spatial orientation of channel turrets with differential sequence lengths and identities, conformational changes and molecular surface properties, the potassium channel turrets can be divided into the following three states: open state with less hindering effects on toxin binding, half-open state or half-closed state with certain effects on toxin binding, and closed state with remarkable effects on toxin binding. In this review, we summarized the diverse structural features of potassium channels explored using scorpion toxin tools and discuss future work in the field of scorpion toxin-potassium channel interactions.

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Selek, M., S. Tasdemir, K. Dincer, and S. Baskaya. "Experimental examination of the cooling performance of Ranque-Hilsch vortex tube on the cutting tool nose point of the turret lathe through infrared thermography method." International Journal of Refrigeration 34, no. 3 (May 2011): 807–15. http://dx.doi.org/10.1016/j.ijrefrig.2010.11.008.

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Derks, A., C. Beck, and V. Martínez Pillet. "Inferring telescope polarization properties through spectral lines without linear polarization." Astronomy & Astrophysics 615 (July 2018): A22. http://dx.doi.org/10.1051/0004-6361/201731231.

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Context. Polarimetric observations taken with ground- or space-based telescopes usually need to be corrected for changes of the polarization state in the optical path. Aims. We present a technique to determine the polarization properties of a telescope through observations of spectral lines that have no or negligible intrinsic linear polarization signals. For such spectral lines, any observed linear polarization must be induced by the telescope optics. We apply the technique to observations taken with the Spectropolarimeter for Infrared and Optical Regions (SPINOR) at the Dunn Solar Telescope (DST) and demonstrate that we can retrieve the characteristic polarization properties of the DST at three wavelengths of 459, 526, and 615 nm. Methods. We determine the amount of crosstalk between the intensity Stokes I and the linear and circular polarization states Stokes Q, U, and V, and between Stokes V and Stokes Q and U in spectropolarimetric observations of active regions. We fit a set of parameters that describe the polarization properties of the DST to the observed crosstalk values. We compare our results to parameters that were derived using a conventional telescope calibration unit (TCU). Results. The values for the ratio of reflectivities X = rs∕rp and the retardance τ of the DST turret mirrors from the analysis of the crosstalk match those derived with the TCU within the error bars. We find a negligible contribution of retardance from the entrance and exit windows of the evacuated part of the DST. Residual crosstalk after applying a correction for the telescope polarization stays at a level of 3–10% regardless of which parameter set is used, but with an rms fluctuation in the input data of already a few percent. The accuracy in the determination of the telescope properties is thus more limited by the quality of the input data than the method itself. Conclusions. It is possible to derive the parameters that describe the polarization properties of a telescope from observations of spectral lines without intrinsic linear polarization signal. Such spectral lines have a dense coverage (about 50 nm separation) in the visible part of the spectrum (400–615 nm), but none were found at longer wavelengths. Using spectral lines without intrinsic linear polarization is a promising tool for the polarimetric calibration of current or future solar telescopes such as the Daniel K. Inouye Solar Telescope (DKIST).

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Ronza, Paolo, José Antonio Álvarez-Dios, Diego Robledo, Ana Paula Losada, Roberto Romero, Roberto Bermúdez, Belén G. Pardo, Paulino Martínez, and María Isabel Quiroga. "Blood Transcriptomics of Turbot Scophthalmus maximus: A Tool for Health Monitoring and Disease Studies." Animals 11, no. 5 (April 30, 2021): 1296. http://dx.doi.org/10.3390/ani11051296.

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Blood transcriptomics is emerging as a relevant tool to monitor the status of the immune system and assist in diagnosis, prognosis, treatment and pathogenesis studies of diseases. In fish pathology, the potential of transcriptome profiling of blood is still poorly explored. Here, RNA sequencing was applied to analyze the blood transcriptional profile of turbot (Scophthalmus maximus), the most important farmed flatfish. The study was conducted in healthy specimens and specimens parasitized by the myxozoan Enteromyxum scophthalmi, which causes one of the most devastating diseases in turbot aquaculture. The blood of healthy turbot showed a transcriptomic profile mainly related to erythrocyte gas transportation function, but also to antigen processing and presentation. In moderately infected turbot, the blood reflected a broad inhibition of the immune response. Particularly, down-regulation of the B cell receptor signaling pathway was shared with heavily parasitized fish, which showed larger transcriptomic changes, including the activation of the inflammatory response. Turbot response to enteromyxosis proved to be delayed, dysregulated and ineffective in stopping the infection. The study evinces that blood transcriptomics can contribute to a better understanding of the teleost immune system and serve as a reliable tool to investigate the physiopathological status of fish.

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Güğerçin, Utku. "Bir Dış Kaynak Kullanım Aracı Olarak Türkiye’de Doğrudan Borçlandırma Sistemi." İktisadi ve İdari Bilimler Fakültesi Dergisi 19, no. 1 (June 1, 2017): 21–32. http://dx.doi.org/10.5578/jeas.29150.

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P V, Prashanth, and Sachidananda H K. "Design and Fabrication of Special Purpose Tool Fixture for CNC Turrets." International Journal of Mechanical Engineering 3, no. 1 (January 25, 2016): 17–21. http://dx.doi.org/10.14445/23488360/ijme-v3i1p104.

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Ardhiansyah, Fahmy, Aries Sulisetyono, and Wasis Dwi Aryawan. "Heading Analysis of Weathervaning Turret Moored Units." Applied Mechanics and Materials 874 (January 2018): 64–70. http://dx.doi.org/10.4028/www.scientific.net/amm.874.64.

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This paper presents the heading analysis study of weathervaning turret moored unit. Design wave heading is to be in accordance with the operational conditions for the sea states contributing the most to the long term value of the dominant load effect. From the heading analysis over each of the sea states contained in the time-series, the mean heading of the floating structure can be obtained.The objective of this study is to assess heading analysis outcome as function of heading probability occurrences of weathervaning turret moored floating units and to identify dominance environment load component act to the system.In order to achieve the above objective, the numerical model has been developed. The model is generate a vessel model by describing the capability to weathervane. It will be performed with MOSES software packages and numerical tools, both in the time-domain and frequency-domain.The heading analysis results indicates that the most affected external forces is dedicated by wind, it is seen the relative heading between wind and vessel heading is quite small (<10degree) with large occurrence probability (up to 60%). The proposed double static approach method to solve heading analysis has been investigated by comparing to former approach which is found a good result agreement between them.

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ABE, Masaru, Jiro SAKAMOTO, and Kenichi NAKANISHI. "Development of thermal deformation analysis model of multitasking machine tool with turrets considering bed." Proceedings of The Computational Mechanics Conference 2018.31 (2018): 192. http://dx.doi.org/10.1299/jsmecmd.2018.31.192.

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ALONSO, MERCEDES, FÁTIMA C. LAGO, MARÍA GÓMEZ-REINO, JACOBO FERNÁNDEZ, IRIS MARTÍN, JUAN M. VIEITES, and MONTSERRAT ESPIÑEIRA. "Fast Real-Time PCR assay for detection of Tetramicra brevifilum in cultured turbot." Parasitology 140, no. 3 (October 15, 2012): 338–42. http://dx.doi.org/10.1017/s0031182012001655.

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SUMMARYGlobal aquaculture production of turbot has rapidly increased worldwide in the last decade and it is expected to have even bigger growth in the next years due to new farms operating. The losses caused by pathogen infections have grown at the same time as the production of this species. Parasitological infections are among the main relevant pathologies associated with its culture and produce serious losses in aquaculture, reduce the growth rate in fish and may lead to unmarketable fish due to skeletal muscle abnormalities in cases with high intensity of infection. The microsporidian parasite Tetramicra brevifilum causes severe infections and generates major losses in farmed turbot. Infections are difficult to control due to spore longevity and its direct transmission. To facilitate the infection management, an effective tool for fast detection and identification of T. brevifilum is needed. This study provides a molecular methodology of fast Real-Time PCR for T. brevifilum detection to the aquaculture industry, useful for routine control of T. brevifilum at turbot farms. The method is characterized by its high specificity and sensitivity, and it can be applied to cultured turbot for parasite detection regardless of the life-cycle stage of the pathogen or the infection intensity.

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Aydin, Ilhan. "The Effect of Ploidy on Growth and Feeding Pattern of Diploid and Triploid Turbot Scophthalmus maximus Under Communal Rearing Condition." Turkish Journal of Fisheries and Aquatic Sciences 21, no. 06 (March 8, 2021): 275–81. http://dx.doi.org/10.4194/1303-2712-v21_6_02.

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Triploidy induction is a useful tool to produce sterile fish that prevents interbreeding of farmed fish with wild counterparts. In this study, growth performance and feed conversion rates of 12-months old diploid and triploid turbot that reared both communally and separately for 16 months at constant water temperature determined. At the end of the experiment, diploid, triploid, and communally reared groups reached an average weight of 672.4±21.0 g, 659.2±25.3 g and 660.5±12.0 g, respectively. Any significant differences were not observed in the weight of separately reared diploid and triploid turbot groups. In contrast, triploid fish in the communal group were significantly heavier than diploids at the end of the rearing period. The feed conversion rate of the ploidy group did not show any significant difference between groups. The highest mean specific growth rate was observed in the triploids in communal groups, whereas the diploids in communal groups had the lowest mean specific growth rate. The weight and length gain rates of the groups were similar. Diploid turbot growth appeared to be negatively affected by communal ploidy rearing. The results of the present study indicate that triploid turbot farm escapees may be advantageous in terms of growth in nature.

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EMELIANOV, VLADIMIR V. "TWO LETTERS BY V.V. ROZANOV TO B.A. TURAEV FROM THE ARCHIVES OF THE STATE HERMITAGE MUSEUM." Study of Religion, no. 1 (2021): 136–41. http://dx.doi.org/10.22250/2072-8662.2021.1.136-141.

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The article publishes two letters of the Russian philosopher and writer V.V. Rozanov to the master of general history B.A. Turaev. The letters were found in the archives of the State Hermitage Museum in a folder of documents from unidentified correspondents of Turaev. One letter has no date, the second one is dated October 13, 1898. The data from the letters found allow dating Rozanov and Turaev's acquaintance to no earlier than May 9, 1898, when the debate on Turaev's master's thesis “God Thoth” took place. In the first letter Rozanov introduces himself to Turaev and asks permission to call at him to discuss topics on the history of ancient Egypt, which Rozanov was interested in. In the second letter, Rozanov thanks Turaev for reprints of articles and expresses his views on a number of issues related to these papers. Both letters are viewed against the background of Rozanov's Egyptian myth and Rozanov's controversial attitude toward professional Egyptologists.

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Brown, R. Lane, Leatha L. Lynch, Tammie L. Haley, and Reza Arsanjani. "Pseudechetoxin Binds to the Pore Turret of Cyclic Nucleotide–gated Ion Channels." Journal of General Physiology 122, no. 6 (November 24, 2003): 749–60. http://dx.doi.org/10.1085/jgp.200308823.

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Peptide toxins are invaluable tools for studying the structure and physiology of ion channels. Pseudechetoxin (PsTx) is the first known peptide toxin that targets cyclic nucleotide–gated (CNG) ion channels, which play a critical role in sensory transduction in the visual and olfactory systems. PsTx inhibited channel currents at low nM concentrations when applied to the extracellular face of membrane patches expressing olfactory CNGA2 subunits. Surprisingly, 500 nM PsTx did not inhibit currents through channels formed by the CNGA3 subunit from cone photoreceptors. We have exploited this difference to identify the PsTx-binding site on the extracellular face of CNG channels. Studies using chimeric channels revealed that transplantation of the pore domain from CNGA2 was sufficient to confer high affinity PsTx binding upon a CNGA3 background. To further define the binding site, reciprocal mutations were made at 10 nonidentical amino acid residues in this region. We found that two residues in CNGA2, D316 and Y321, were essential for high-affinity inhibition by PsTx. Furthermore, replacement of both residues was required to confer high-affinity PsTx inhibition upon CNGA3. Several other residues, including E325, also form favorable interactions with PsTx. In the CNGA2-E325K mutant, PsTx affinity was reduced by ∼5-fold to 120 nM. An electrostatic interaction with D316 does not appear to be the primary determinant of PsTx affinity, as modification of the D316C mutant with a negatively charged methanethiosulfonate reagent did not restore high affinity inhibition. The residues involved in PsTx binding are found within the pore turret and helix, in similar positions to residues that form the receptor for pore-blocking toxins in voltage-gated potassium channels. Furthermore, biophysical properties of PsTx block, including an unfavorable interaction with permeant ions, also suggest that it acts as a pore blocker. In summary, PsTx seems to occlude the entrance to the pore by forming high-affinity contacts with the pore turret, which may be larger than that found in the KcsA structure.

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Chair, M., H. J. Nelis, P. Leger, P. Sorgeloos, and A. P. de Leenheer. "Accumulation of trimethoprim, sulfamethoxazole, and N-acetylsulfamethoxazole in fish and shrimp fed medicated Artemia franciscana." Antimicrobial Agents and Chemotherapy 40, no. 7 (July 1996): 1649–52. http://dx.doi.org/10.1128/aac.40.7.1649.

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In a previous paper (H.J. Nelis, P. Léger, P. Sorgeloos, and A. P. De Leenheer, Antimicrob. Agents Chemother. 35:2486-2489, 1991) it was reported that two selected antibacterial agents, i.e., trimethoprim and sulfamethoxazole, can be efficiently bioencapsulated in nauplii of the brine shrimp Artemia franciscana for administration to fish. This follow-up study showed that larvae of the sea bass and the turbot as well as postlarvae of the white shrimp accumulate the therapeutic agents in high quantities when fed medicated A. franciscana. To monitor their levels as a function of time, the liquid chromatographic method originally developed for the analysis of A. franciscana was modified with respect to chromatography, internal standardization, and sample pretreatment. The levels of trimethoprim ranged from 1 to 7 micrograms/g (sea bass), 1 to 13 micrograms/g (turbot), and 4 to 38 micrograms/g (white shrimp). The corresponding values for sulfamethoxazole were 0.3 to 4 micrograms/g (sea bass), 1 to 42 micrograms/g (turbot), and 4 to 35 micrograms/g (white shrimp). Only the two fish species, unlike the shrimp, metabolized the latter to N-acetylsulfamethoxazole (concentration range, 1 to 10 micrograms/g). These data suggest the potential of the bioencapsulation of therapeutic agents in live food as a tool to control infectious diseases in aquaculture. A preliminary challenge test also confirmed the in vivo efficacy of this approach.

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Xing, Jing, Xiujuan Zhou, Xiaoqian Tang, Xiuzhen Sheng, and Wenbin Zhan. "Characterization of Toll-like receptor 22 in turbot ( Scophthalmus maximus )." Fish & Shellfish Immunology 66 (July 2017): 156–62. http://dx.doi.org/10.1016/j.fsi.2017.05.025.

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Journal articles on the topic 'Tool turret'

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