• 한국조명전기설비학회지:조명전기설비
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• 제13권2호
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• pp.187-187
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• 1999

in order to perform a elaborate task like as assembly, manufacturing and so forth of components, tracking control on the trajectory of power coming in contact with a target as well as tracking control on the movement course trajectory of end-effector is indispensable. In this paper, to bring under robust and accurate control of auto-equipment systems which disturbance, parameter alteration of system, uncertainty and so forth exist, neural network controller called dynamic neural processor(DNP) is designed. Also, the learning architecture to compute inverse kinematic coordinates transformations in the manipulator of auto-equipment system is developed and the example that DNP can be used is explained. The architecture and learning algorithm of the proposed dynamic neural network, the DNP, are described and computer simulation are provided to demonstrate the effectiveness of the proposed learning method using the DNP.

• 대한기계학회논문집A
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• 제25권9호
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• pp.1317-1324
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• 2001

In this paper, a methodology of geometrical error identification and compensation for NC machine tool position is developed. We propose a reference artifact with measuring the geometry of coordinate system for compensating linear scale error of NC machine. The coordinate system of the NC machine could be compensated successfully with the information obtained by measuring the reference artifact and our compensation algorithm. Monte Carlo simulation is used to evaluate coordinate referencing ability and, the uncertainties of the machine tool position is estimated and observed through the compensation process by simulation.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2005년도 춘계학술대회 논문집
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• pp.370-376
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• 2005

This paper is described the program algorithm which can easily estimate dynamics of test support system by using mathematica tool based on the finite element method. We can determine the geometry, dimensions of the test support system, through tool stated in this paper for a certain test conditions. As a result of computer simulation and manufactured test support system's experiment in oder to verify suggested program, the dynamics of the test support system was well correspondent each other.

• 반도체디스플레이기술학회지
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• 제9권4호
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• pp.45-50
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• 2010

This paper explores a new approach for modeling of decision-making problems that involve uncertain, time-dependent and sequence-dependent processes which can be applied to semiconductor industry. In the proposed approach, which is based on probability theory, approximate sample paths are required to be specified by probability and statistic characteristics. Completely specified sample paths are seen to be elementary and fundamental outcomes of the related experiment. The proposed approach is suitable for modeling real processes more accurately. A case study is applied to a single item production planning problem with continuous and uncertain demand and the solution obtained by the approximate path specification method shows less computational efforts and practically desirable features. The application possibility and general plan of the proposed approach in semiconductor manufacturing process is also described in the paper.

• International Journal of Ocean System Engineering
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• 제1권1호
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• pp.16-27
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• 2011

The depth and heading control of an autonomous underwater vehicle (AUV) are considered to follow the predetermined depth and heading angle. The proposed control algorithm was based on a sliding mode control, using estimated hydrodynamic coefficients. The hydrodynamic coefficients were estimated employing conventional nonlinear observer techniques, such as sliding mode observer and extended Kalman filter. Using the estimated coefficients, a sliding mode controller was constructed for a combined diving and steering maneuver. The simulated results of the proposed control system were compared with those of a control system that employed true coefficients. This paper demonstrated the proposed control system, and discusses the mechanisms that make the system stable and accurately follow the desired depth and heading angle in the presence of parameter uncertainty.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2005년도 추계학술대회논문집
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• pp.88-91
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• 2005

Although the MEMS element is made through a very precise manufacturing process, usually there is the difference between the modeling design and the actual product. So tuning is required. Through the frequency tuning(changing the characteristics of device), we can calibrate the fabrication error and uncertainty. I'll propose the method of changing the natural frequency through the imposing the axial force on the anchor part to separate the sensing part and the tuning part. When the shape of section is the form of rectangular, the degree of the natural frequencies' change under axial force appears D be different. Applying a tuning force of 30 $\mu$N, the natural frequencies' difference can be reduced by 5 percent.

• Asian Journal of Innovation and Policy
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• 제7권3호
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• pp.581-605
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• 2018

In the soft drink industry, especially small and medium enterprises in Japan, there is a possibility of conversion from a labor-intensive industry to a capital-intensive. The demand for soft drinks may not be satisfied in the summer because the supply is too low to meet the demand. To address this situation, this paper proposes optimal investment that integrates demand uncertainty, based on real options approach (ROA) and seasonal autoregressive integrated moving average. Two alternative options are compared and evaluated. One is the Bermudan option: to employ additional workers to elevate efficiency in summer and laying off in winter, this attitude is repeated each year. The other is the American option: to replace equipment to increase machine ability throughout the year. Results in ROA show that the highest improvement is gained if the two options are in a symbiotic relationship. Soft drink producers should search for replacing equipment, using the employees repeatedly. A temporary decision is not equal to an infinite decision.

• 한국정밀공학회지
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• 제11권1호
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• pp.63-70
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• 1994

This paper presents manufacturing and evaluation of a non-contact rotational torque measurement system which consists of torque cell, telemeter system, transmitter and receiver coil, transmitter, receiver and telemeter indicator. Static calibration test results show that the system has a maximum uncertaintry of 05% or less. A standar calibration system for rotational torque is used to evaluate the measurement system, As a result, the maximum uncertainty for measuring rotational torque by this system is 2% or less. We may conclude that the measurement system is sufficient to measure rotational torque of shaft in industry.

• Journal of applied mathematics & informatics
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• 제42권2호
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• pp.379-390
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• 2024

This study proposes a fuzzy inventory model for managing large-scale production, incorporating cost considerations. The model accounts for two types of expenditure scenarios-parametric and exponential. Uncertainty surrounds holding costs, setup costs, and demand rates. The approach considers a supply chain system with a complex manufacturing process, factoring in transportation costs based on the quantity of goods and distance between the supplier and retailer. The initial crisp model is then transformed into a fuzzy simulation, incorporating specific fuzzy variables affecting inventory costs. The proposed method significantly reduces overall inventory costs for the entire supply chain. Retailer demand is linked to inventory levels, and vendor/distributor storage deteriorates over time. The fuzzy condition assumes hexagonal variables for all associated factors. The study employs the signed distance method for defuzzification to determine the optimal order quantity with hexagonal fuzzy numbers. Mathematical examples are provided to illustrate the practicality of the proposed approach.

• 벤처혁신연구
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• 제5권4호
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• pp.109-115
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• 2022

본 연구는 주요국 정책을 토대로 중소 제조기업의 디지털 전환 현황과 문제점을 진단하고, 이에 대응하기 위한 개선방안을 제시하고자 한다. 디지털 전환은 비대면 경제 및 디지털 기술에 대한 요구가 부상하면서 산업 패러다임이 변화하였다. 이에 주요국들은 디지털 전환 관련 정책을 추진중에 있으며, 우리나라도 한국형 뉴딜 정책을 시행중에 있다. 다만, 한편, 우리나라는 주요국의 디지털 전환 정책 전략을 그대로 차용하고 있어 우리의 강점 활용 및 단점 보완을 할 수 있는 한국형 모델이 결핍되어 있다. 따라서 한국의 독자적인 표준화 작업이 시급히 진행되어야 한다. 또한 기존에는 스마트공장 보급 및 확산, 즉 양적 정책에 초점이 맞춰서 진행되었다면, 앞으로는 데이터의 활용 및 성과창출을 지향할 수 있는 질적 정책으로의 전환이 필요하다. 즉, 스마트공장 지원정책의 고도화 정책을 통하여 질적 수준을 제고시킬 수 있는 정책적 보완이 필요하다. 이에 사업의 유기적인 연계와 효율적 지원을 위하여 기관별로 추진하고 있는 정책을 공유할 필요가 있다. 따라서 사업의 유기적인 연계와 효율적 지원을 위하여 기관별로 추진 중인 정책을 공유할 필요가 있다. 중소기업의 디지털 전환에 대한 인식 수준을 제고하고 중장기적으로 기술 및 솔루션 개발을 지원해야 한다. 따라서 향후 중소 제조기업의 디지털 전환 정책은 중소기업의 질적 수준시킬 수 있는 방안을 모색할 필요가 있다는 것을 제시함 점에서 실무적인 의의가 있다.