• 디지털산업정보학회논문지
• /
• 제10권1호
• /
• pp.55-60
• /
• 2014

Today, there is increasing the elderly population in rural community, and people of returning from the urban to the rural community are demand to be of high value-added agriculture. In this time, there are required to regularization, standardization, automation, for getting of production of high value crops. In this paper, we are study for automation cultivation control system design for produce high-value crops. this system were designed of two parts that one part is measure and control unit, another part is server part for database and server side control. the main controller for measurement and control is used MC9S08AW60, server for Database and server-side control was using MySQL with CentOS. The source code of control program was coding C and compile with GCC. the functions of measurement and control unit are digital input and output each 8channels and can be scan-able of 20 Bit with 2CH/Sec. Analog Output were designed that can be output of 4-20mA or 0-5V on 4channel. The Digital input and output part were designed 8-channel, and using the high speed photo coupler and relays. We showed that system is possible to measure a 20bit data width, 2Ch/sec as 8 channel analog signals.

• Journal of Electrical Engineering and Technology
• /
• 제9권5호
• /
• pp.1447-1453
• /
• 2014

This paper proposes the new method based on the availability of three points measurement and convexity of photovoltaic (PV) curve characteristic at the maximum power point (MPP). In general, the MPP tracking (MPPT) function is the important part of all PV systems due to their power-voltage (P-V) characteristics related with weather conditions. Then, the analog-to-digital converter (ADC) and low pass filter (LPF) are required to measure the voltage and current for MPPT by the digital controller, which is used to implement the PV power conditioning system (PCS). The measurement and quantization error due to rounding or truncation in ADC and the delay of LPF might degrade the reliability of MPPT. To overcome this limitation, the proposed method is proposed while improving the performances in both steady-state and dynamic responses based on the detailed investigation of its properties for availability and convexity. The performances of proposed method are evaluated with the several case studies by the PSCAD/EMTDC$^{(R)}$ simulation. Then, the experimental results are given to verify its feasibility in real-time.

• 정보처리학회논문지B
• /
• 제13B권2호
• /
• pp.83-88
• /
• 2006

일정한 형태의 물체를 분석하기 위해 사용되는 각-거리 그래프를 이용하여 임의의 물체의 경계선 내부 영역의 면적을 측정하는 디지털 영상처리 알고리듬을 제안한다. 물체의 경계선 내부의 한 점을 중심으로 1차 각-거리 그래프를 생성하고 이 그래프로부터 거리 값이 급격히 변화하는 위치를 추출하여 1차 그래프에서 접근하지 못한 영역을 인식하여 새 영역에서의 한 점을 중심으로 2차 각-거리 그래프를 생성한다. 물체의 형태가 복잡한 경우 차수가 증가하게 되며 이와 같이 계층적으로 구성된 각-거리 그래프 그룹에 대해 거리의 제곱을 각도 방향으로 적분하여 물체의 경계선 내부 영역의 면적을 측정한다.

• 한국기계가공학회지
• /
• 제20권12호
• /
• pp.71-77
• /
• 2021

An impeller identification technique that is essential for adding viscosity measurement functions to overhead stirrers is presented in this study. Previous studies have revealed that using magnets facing the same poles arranged in a row can aid in distinguishing the types of impellers by detecting the number of magnets in a non-contact manner. However, as these previous studies measured the magnetic fields using analog Hall sensors, a converting circuit for the digital signals is required that can interface with the MCU. In this study, it was demonstrated that the number of magnets can be distinguished without using a separate conversion circuit by using a Hall sensor with a digital output. Owing to the unique hysteresis characteristics of digital Hall sensors, it was confirmed through experiments that the complex and diverse outputs appear depending on the direction of the magnetic field, the arrangement of magnetic poles, and the moving direction of the magnet. The measurement of the magnetic field showed that an edge signal equal to the number of magnets inserted into the impeller was detected when the radial direction was used, and the south pole was first approached.

• Current Optics and Photonics
• /
• 제7권4호
• /
• pp.337-344
• /
• 2023

Three-point bending is the main method for measuring the elastic modulus of a thin plate. Although various displacement transducers may be used to measure the bending, these are single-point measurements, and it is difficult to eliminate the error caused by eccentric load and shear force. Error-correction models for the elastic modulus of quartz glass using digital speckle interferometry are proposed for eccentric load and shear force. First, the positional misalignment between maximum deflection and load is analyzed, and the error caused by eccentric load is corrected. Then, the additional displacement caused by shear force at different positions of the quartz glass plate is explored. The effect of shear deformation is also corrected, by measuring two points. Since digital speckle interferometry has the advantage of full-field measurement, it can simultaneously obtain deflection data for multiple points to realize error correction. Experimental results are presented to demonstrate that the proposed model can effectively correct the measurement error of the elastic modulus.

• 디지털융복합연구
• /
• 제6권4호
• /
• pp.63-71
• /
• 2008

This study researches the effectiveness of interactive TV advertising focusing on the factors of audience involvement and interaction. The study began with the effective measurement of interactive television advertisements. Interactive television advertisements have different concepts than existing television advertisements. This study mainly focuses on the characteristics of audience interaction and experiments based on the data of 78 persons for measurement. In the experiments, the characteristics were categorized according to search time, specifically the number of searched pages about interactive television advertisement. Hypothesis 1 reveals that the interaction of the audience increases when the advertising attitude, brand attitude, and purchase intentions also increase. Hypothesis 2 finds that the involvement of the audience increases when the advertising attitude, brand attitude, and purchase intentions also increase. By studying these consumer characteristics and behavior, a new method of effective measurement for interactive television advertisement is uncovered. The new method includes not only existing measurement elements of television advertisement which include attitude about advertising and brand, and customer purpose, but also the features of interactive television advertisement like customer search time. According to this research on interactive television advertisement, the interaction with and involvement of the audience are highly influential variables.

• 조명전기설비학회논문지
• /
• 제25권2호
• /
• pp.113-119
• /
• 2011

A frequency in electrical power system changes by the load fluctuation in utility grid, has an influence on a connected generator, and ultimately brings a big trouble in the power system. Therefore, a quick measurement of system frequency and governor control of power system is a very important factor in the reliability and the economic feasibility. Electromagnetic frequency relays in the past had the large power consumption and the difficulty of accurate measurement. After Researched and developed digital relays are very affected by the noise and the distortion, and the recently developed Microprocessor relays have problems of expensive device and time when measuring the frequency at 50[ms]. In this study, An improve algorithm that measures the power system frequency quickly and accurately is suggested, simulated by using Matlab and programmed using C code through DSP6713 KIT. This algorithm is tested to the arbitrary voltage waveform input. The results show that the suggested algorithm is effective in the accurate and quick frequency measurements.

• Smart Structures and Systems
• /
• 제3권3호
• /
• pp.373-384
• /
• 2007

For structural health monitoring (SHM) of civil infrastructures, displacement is a good descriptor of the structural behavior under all the potential disturbances. However, it is not easy to measure displacement of civil infrastructures, since the conventional sensors need a reference point, and inaccessibility to the reference point is sometimes caused by the geographic conditions, such as a highway or river under a bridge, which makes installation of measuring devices time-consuming and costly, if not impossible. To resolve this issue, a visionbased real-time displacement measurement system using digital image processing techniques is developed. The effectiveness of the proposed system was verified by comparing the load carrying capacities of a steel-plate girder bridge obtained from the conventional sensor and the present system. Further, to simultaneously measure multiple points, a synchronized vision-based system is developed using master/slave system with wireless data communication. For the purpose of verification, the measured displacement by a synchronized vision-based system was compared with the data measured by conventional contact-type sensors, linear variable differential transformers (LVDT) from a laboratory test.

• 대한전기학회논문지:전력기술부문A
• /
• 제53권7호
• /
• pp.365-374
• /
• 2004

The relay measures the frequency of the power system in order to detect faults and separate them from the system. Many estimation algorithms for the relay have been proposed to accurately measure the frequency. This paper proposes a new frequency measurement method using the digital phase locked-loop(DPLL) for the relay of the power system. The proposed method is configured with a DPLL scheme and verified through computer simulations and experimental tests. In order to cope with noises in the power system, filters are included in the input signal processing part and the frequency comparator. MATLAB is used for computer simulations and an experimental setup with a CPU and an FPGA(Field Programmable Gate Array) is constructed. The loop filter of the DPLL is run in the CPU software In adjust parameters and others are in the FPGA. Experimental tests are performed lot a function generator and the power system. Results show that the proposed method is appropriate to the frequency measurement for the relay.

• 디지털융복합연구
• /
• 제11권3호
• /
• pp.101-113
• /
• 2013

기존의 방법론 관련 문헌에서는 반영적 지표를 기반으로 다측정 지표들의 개발과 타당성 검정에 관한 다양한 문헌적 고찰을 수행하였음에도 불구하고 형성적 지표에 대한 관심은 부족하였다. 본 연구의 목적은 형성적 지표를 사용함에 있어서 필요한 접근법에 대한 연구자들의 이해를 돕기 위함이다. 또한 연구자들이 자신의 모델을 위해 필요한 적합한 지표의 선택에 도움을 제공하기 위해 형성적 지표의 본질에 대해서도 살펴보고자 한다. 이를 위해 형성적 지표에 대한 기반이론을 살펴보고 다음으로 실증 분석에서 사용된 사례를 통해 형성적 지표의 접근법과 연구수행 절차에 대해 살펴본다. 마지막으로 실증 연구에서 지표의 사용에 관한 제언을 하고자 한다.