老莊과 Le Guin의 공조와 협업 - The Lathe of Heaven 읽기 1

이승수,우미영 한국도교문화학회 2023 道敎文化硏究 Vol.59 No.-

This study proposes the method for text reading by summarizing the researches on The Lathe of Heaven and analyzing its narrative structure. Chapter 2 investigated the research status and trends. In accordance with the discussion in the English-American countries, the fictions by Le Guin have three characters, SF, Fantasy and Utopia with the world view of the Lao-Zhuang as the common denominator. Of his fictions by Le Guin, The Lathe of Heaven was selected as the works expressing the world view of the master the most strongly as soon as it was published and so every aspect of the fiction was reasonably analyzed. In the context of Utopia discourse, ambiguous background and significance of utopia setting with open conclusion were highlighted. The analysis in this study identified the position of The Lathe of Heaven in the utopia literature history, weak points of existing utopia fictions, concerns and pursuit of Le Guin and continuity with H.G. Wells. Introduction of the works by Le Guin in Korea rapidly increased since 2000 and the research on his works was earnestly started from 2010. Unfortunately, there is no thesis that thoroughly analyzes The Lathe of Heaven in Korea until now. Chapter 3 examined the complicated and difficult narrative composition from the titles to character relationship. The meaning related to titles was analyzed in terms of the interpretation of symbols in the works and the overall structural technique consisting of beginning, development and conclusion was identified. On the basis of the contents of description, the order of narrative time was reconfigured and the symbolism of the Willamette river in Portland, the place of narration, was examined. No. 18 dream of Orr and Haber was summarized in the table and the fantasy element of their dream was explained. Moreover, this study analyzed correlation of literature history or intertextuality activated in the relationship of three characters around Orr. The relation of Orr and Haber is the narrative variation of Ward No. 6 by Chekhov, and the relation of Orr and Lelache is the realization of the songs by The Beatles which was very popular at that time. Furthermore, the relation of Orr and an alien is the reproduction of “Journey to Find the Self(探我記)” in Zhuangzi. It is the narrative composition and aesthetics. Personalia from the perspective of Lao-Zhuang, functions of epigraph, and the characteristics of mythpoetics embracing all above will be the tasks for the further study.

NC 선반의 직선 사이클 평면 위치결정 정도 측정 및 분석

김영석,정정표,한지희,윤원주 朝鮮大學校 機械技術硏究所 2003 機械技術硏究 Vol.6 No.2

It is very important t o measure linear cycle plane positioning accuracy of NC lathes because the plane positioning accuracy affects accuracy, performance, interchange-ability and quality of machine parts machined by the NC lathes in industries. Until now, linear cycle plane positioning accuracy test of NC lathes has not been carried out because the two axes of NC lathe are moving simultaneously crossing a t right angle each other. while positioning accuracy test of one axis of NC lathe is briskly carried out using a laser interferometer system in industries. So, in this study, a measuring units system to measure simultaneously two axes' plane. positioning accuracy of NC lathe was composed of two optical linear scales installed on the. z and x-axis of work coordinate system on NC lathe and a computer inserted with PC counter card enables to obtain measuring data. Here, ATC(Automatic Tool Changer) and moving part of linear scale are fixed with magnet bases in order to measure displacement of the ATC of NC lathe. And next, computer software was developed in order to measure the lathe under resolution of 0.1㎛ by the linear scales, and also computer soft measuring data could be modeled on plots and be analyzed to numerically.

갈이틀(旋車)의 명칭과 磨造匠의 소임

최공호(崔公鎬) 한국미술연구소 2016 美術史論壇 Vol.- No.43

A lathe is a traditional cutting machine that cuts materials by turning its rotating shaft. The origin of lathe is long enough to trace back to Greece in 1100 BC and it is very useful and universal technique that has been passed down today to all cultural areas in different ways. In Korea the vestige of lathe was also found in the relic of Baekje from the 6th century and it has been made good use of for everyday materials and the utensils used in ancestral rites until recently. However there has been no studies on various names of lathe, their meanings and duties of Majojang, a master of millstone who manages the use of lathe. Causual studies are desperately needed on traditional techniques including materials, tools and techniques to advance towards the level of technology culture through restoration of craftworkers" reality and expansion of study landscape.

선반 구조변경을 위한 현장용 공구대 강성계산모델

허성혁(Seong-Hyeok Heo),김수진(Su-Jin Kim) 한국기계가공학회 2017 한국기계가공학회지 Vol.16 No.5

In this research, a practical stiffness calculation method is developed and applied for modifying the height of the headstock, turret, and tailstock of a CNC lathe to enlarge the turntable diameter. The casting structure is assumed to be a rigid body and the linear motion element to be an elastic spring to simplify the turret stiffness calculation model. The stiffness of the sliding guide and ball screw of the original lathe is measured with a push tester and LVDT sensor, and the turret stiffness of the modified lathe is predicted and compared with experimental results to verify the model. The measured stiffness of the original turret is 0.17 kN/μm and that of the modified turret is 0.11 kN/μm, i.e., an 18% difference from the predicted result. The verified stiffness calculation model can be used to develop another modified lathe.

가상현실 기반 범용 선반 교육 시스템

박원형,송인희,김상연 한국지식정보기술학회 2018 한국지식정보기술학회 논문지 Vol.13 No.5

One of the advantages in virtual reality (VR) is that it can provide indirect experience to users without the space and the time limitations. Furthermore, the VR allows users to avoid every dangerous situations in a various environment, so the VR is a best method to practice manufacturing devices, which can be occurred in dangerous conditions. Therefore, this paper proposes a VR based education system for a general lathe. The proposed system is composed of an head mounted display, controllers, a foot tracker, and a PC. The virtual environment was designed using Unity 3D. A user can study the general lathe with two modes, a study mode and a practice mode. A user can get the information of the general lathe’s each part and a basic to use the general lathe. In the practice mode, a user can select a material and a blueprint, and can control a spindle speed, a handle, and a break paddle by gestures. Furthermore, we recorded real sounds according to the materials and spindle speeds to enhance the experience of users. Finally, user tests are conducted with working-level workers and non-working-level workers, and compared the proposed system and a previously developed VR based general lathe education system. The results show that the proposed system is suitable for teaching educatee.

정밀 자동선반 공구 유닛의 진동특성 해석

주강우,이윤철,이영식,손정종,이재권,김광선 한국반도체디스플레이기술학회 2016 반도체디스플레이기술학회지 Vol.15 No.1

This paper is about the analysis on the vibration characteristic of tooling units on the precision automatic lathe. The vibration characteristic of the machine tool is emphasized in accordance with the high precision of the various industries Including the various semiconductor devices and components sector. In this paper, the vibration analysis was performed in designed tooling units of precision automatic lathe. Through the analysis, it is calculated that the frequency of distribution in certain areas by review the resonant frequency and the amount of deformation. And designed model was verified to be a stable structure.

Precision Measurement of Z-Slide Vertical Error Motion of an Ultra-Precision Lathe by Using Three-probe Method

Zengyuan Niu,Yuan-Liu Chen,Daiki Matsuura,Jung Chul Lee,Ryo Kobayashi,Yuki Shimizu,So Ito,Wei Gao,오정석,박천홍 한국정밀공학회 2017 International Journal of Precision Engineering and Vol.18 No.5

This paper presents a precision measurement of the Z-slide vertical error motion of an ultra-precision lathe based on a three-probe measurement method. The vertical error motion of the Z-slide, which is composed of the vertical parallelism error motion and the vertical straightness error motion, is measured by utilizing three displacement measuring probes to scan a self-cut roll workpiece and an accurate straightedge, respectively. A series of factors which could influence the measurement of the vertical error motion, including the error motion of the spindle, the surface form error of the reference object and the horizontal error motion of the Z-slide, are all successfully removed by using the proposed three-probe measurement system with an error separation method. The influence of the gravity induced deflection of the roll workpiece on the measurement of the Z-slide vertical parallelism error motion is also discussed. Experiments were carried out to verify the feasibility of the proposed methods on a three-axis ultra-precision lathe. The vertical straightness error motion was evaluated to be 133 nm with a measurement repeatability of 21 nm and the vertical parallelism error motion was evaluated to be 12.1 μm with a measurement repeatability of 38 nm.

Beam Design of Gantry Robot for Attaching and Detaching Workpiece of CNC Lathe

팽기웅(Ki Woong Paeng),이재경(Jae Kung Lee),최명철(Myung Chul Choi),김갑순(Gab Soon Kim) Korean Society for Precision Engineering 2017 한국정밀공학회지 Vol.34 No.7

This paper describes the design of the beam of a gantry robot for Computer numerical control (CNC) lathe that can automatically attach and detach a workpiece. The gantry robot takes the unprocessed workpiece from the stoker and mounts it on the chuck of a CNC lathe. The robot then removes the processed workpiece fixed to the chuck and places it in the processed workpiece stoker. The workpiece consists of a body, x-axis beam, x-axis driving device, y-axis beam, yaxis driving device, z-axis beam and z-axis driving device. Finite element analysis was performed to design the x-axis beam, the y-axis beam, and the z-axis beam. Based on the results, the optimal size of the x-axis beam was designed to have a size of 150 mm × 150 mm × 4681 mm with a thickness of 9 mm. The x-axis beam is less eccentric in the position of the chuck of the CNC lathe.

CNC 선반용 공작물 자동 적재장치의 설계 및 제작

박재경(Jae-Kyung Park),김갑순(Gab-Soon Kim) 한국기계가공학회 2019 한국기계가공학회지 Vol.18 No.5

In this paper, we design a new automatic workpiece loading system for the loading and unloading of a workpiece for a CNC lathe. Conventional workpiece loading systems are bulky and require a large area when installed around a shelf. Therefore, an automatic loading system with small horizontal and vertical dimensions and a large loading capacity was designed. Structural analysis of the system was then carried out to assess the displacement and safety of the main components. Following this, the automatic loading system was manufactured according to the structural analysis results and conceptual design, and experiments characterizing the performance of the system were conducted. As a result, the automatic loading system was found to operate accurately and safely, meaning it can be used to load and unload workpieces for a CNC lathe.

Robust Thermal Error Modeling and Compensation for a Nano Level Thermal Drift in a High Precision Lathe

김병섭,송영찬,박천홍 한국정밀공학회 2011 International Journal of Precision Engineering and Vol. No.

High precision machines require very stable operational environment: temperature control and vibration isolation. Tight temperature control for machines usually demand high cost to operate air conditioners. Some of high precision machines require the ambient temperature changes to maintain within ±0.1 degrees. In this paper, we present a thermal error compensation scheme and experimental results for improving machining accuracy of a high precision lathe. The testbed lathe has X- and Z-axes and they are driven by linear motors and hydrostatic oil bearing. Due to the temperature changes of the ambient air and supplied oil to the hydrostatic bearing, thermal deformation is generated and measured to be as much as 200-300 nm. To identify the dynamic relations between the temperature changes and the thermal drift, a state-space model is used in which state variables are constructed from the input measured temperatures and the output thermal drift data. The identified model is implemented in a servo control loop and the predicted thermal error is compensated by subtracting the predicted thermal drift from the servo command. In our simulation, a thermal error of 97 nm rms over 3hours is reduced to 55 nm rms. Experimental results showed an 30% ~ 60% reduction in thermal drift and supported the validity of our approach.