• Proceedings of the IEEK Conference
• /
• 2006.06a
• /
• pp.281-282
• /
• 2006

This paper proposed a method of the camera calibration for noncontact measure of badly illumination. The method with a semi-automation camera calibration, The user designates minimum 4 points in calibration pattern. The Perspective transformation predicts the remaining point calibration pattern. It uses at input value of the Tsai and it searches a better point, When being smaller allowable error than until, it repeats and it puts out a good calibration result.

• Proceedings of the Computational Structural Engineering Institute Conference
• /
• 2000.10a
• /
• pp.32-39
• /
• 2000

Probabilistic structural design optimization, which is characterized by the so-called probabilistic. constraints which introduce permissible probability of violation, is preferred to deterministic design optimization since unpredictable inherent uncertainties and randomness in structural and environmental properties are to be taken quantitatively into account by probabilistic design optimization. In this paper, the well-known reliability index based MPFP(Most Probable Failure Point) search approach and the newly introduced target performance measure based MPTP(Minimum Performance Target Point) search approach are summarized and compared. The present comparison focuses on the number of iterations required for the estimation of probabilistic constraints and a technique for improvement which removes exhaustive iterations is presented as well. A 10 bar truss problem is examined for this.

• Journal of Institute of Control, Robotics and Systems
• /
• v.18 no.8
• /
• pp.725-730
• /
• 2012

In this paper, we propose the localization algorithm for the cooperative behavior of the swarm robots based on WSN (Wireless Sensor Network). The proposed method is as follows: First, we measure positions of the L-bot (Leader robot) and F-bots (Follower robots) by using the APIT (Approximate Point In Triangle) and the RSSI (Received Signal Strength Indication). Second, we measure relative positions of the F-bots against the pre-measured position of the L-bot by using trilateration. Then, to revise a position error caused by noise of the wireless signal, we use the particle filter. Finally, we show the effectiveness and feasibility of the proposed method though some simulations.

• Journal of the Korean Society for Precision Engineering
• /
• v.15 no.11
• /
• pp.121-129
• /
• 1998

In-plane ESPI(Electronic Speckle Pattern Interferometry) was devised to measure in-plane deformations and rotation of a specimen with laser in this study. ESPI is a optical measuring method to be able to measure the deformations of engineering components and materials in industrial fields. The conventional measuring methods of surface deformations such as the strain gauge have many demerits because they are contact and point-to-point measuring ones. But that ESPI is noncontact, nondestructive and whole field measuring method can overcome previous disadvantages. We used ESPI which is sensitive to in-plane displacement for measuring in-plane deformations of a disk. And the 4-frame phase shifting method was used for the quantitative analysis. First of all, the system calibration was done due to an in-plane rotation before getting deformations of a disk. Finally we showed good agreement between the experiment results and those of the FEA(Finite Element Analysis).

• Journal of the Korean earth science society
• /
• v.31 no.6
• /
• pp.555-562
• /
• 2010

Three-dimensional laser scanner was used to accurately measure any possible strain on a slope under pertaining stress with the time difference of 7 months. The laser scanner has the ability to measure the 3-D coordinate of a target point by calculating the travel time of laser beam between the laser device and the target point, and has been proved to be effective for analysis of the displacement of slopes or large construction. The scanning data measured with time difference were analyzed to find any strain by approaches of plane angle change, curvature variation, twist of frame, displacement of merging point, etc. From the analysis, some weak points showing heavily distorted shape were detected, which was used to design the reinforcement.

• Smart Structures and Systems
• /
• v.3 no.3
• /
• 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.

• New & Renewable Energy
• /
• v.9 no.2
• /
• pp.51-57
• /
• 2013

The Grid code is being strengthen as increase of renewable energy ratio. Especially, the grid connection regulations are continuously being updated for stable operation of power grids. Static grid support and Dynamic grid support must make an accurate measure at Grid connected point because they needs control algorithm individually. It has to exactly measure voltage including switching ripple at the output of the inverter generating system. In addition, it is necessary to have an accurate voltage measurement when the situation rapidly changing the grid impedance is caused by the input of serial impedance of transformer and line impedance as well as Grid Fault Device. In this paper, We propose a new detection method of grid voltage to calculate accurately the r.m.s voltage of the grid connection point along the standard required by the low voltage regulation. We verified performance through simulation grid fault device.

• Journal of Nutrition and Health
• /
• v.1 no.2
• /
• pp.87-91
• /
• 1968

Food and nutritional survey was made on two kinds of milk (one: 30 samples of bottled milk, the others: 30 samples of prepared milk), which are bottled market cow milk in Seoul city to examine the general ingredients, adulteration and degeneration. The results of survey indicated that the bottled milk delivered to home is relatively better than the prepared milk from the view point of food and nutrition. Moreover the quality of the prepared milk is poor because of adulteration through adding water or skim milk powder in order to increase quantity, consequently the prepared milk is under the nutritional standard. However it indicated that some of the bottled milk are rather inferior from the view point of food and nutrition, so certain measure is required for improving the quality of bottled and prepared milk. Most of the bottled milk and the prepared milk containing Coli-form bacteria have a possiblity to harm the citizen's health as a medium of infectious disease, such a fact is really serious problem from the view point of the national health, considering the general trend of milk consumption increase. It is urgent for us to take a scientific inspection on the sanitary management and take a formidable measure in handling of milk.

• The Journal of the Society of Korean Medicine Diagnostics
• /
• v.14 no.1
• /
• pp.101-110
• /
• 2010

Objective : A case of idiopathic spasmodic torticollis rapidly improved after Oriental Medical treatments and supplementary trigger point injection is reported. Methods & Results : The oriental medical treatment for spasmodic torticollis including acupuncture, bee-venum therapy, herb medication, taping therapy, chuna therapy and physical therapy was performed for pain alleviation, and trigger point steroid injections were also performed. The Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS) and the Tsui Score were used for outcome measure of the spasmodic torticollis. After treatment for 15 days, the TWSTRS showed a decrease from 56 to 22.3 and the Tsui score also decreased from 13 to 5. Conclusions : We concluded that the oriental medical treatment including acupuncture, bee-venum therapy and taping therapy rapidly induced spasmodic torticollis to remission.

• Journal of Korean Society for Quality Management
• /
• v.28 no.1
• /
• pp.119-131
• /
• 2000

This paper suggests a new diagnostic measure for detecting influential observations in linear discriminant analysis (LDA). It is developed from a Bayesian point of view using a default Bayes factor obtained from the imaginary training sample methodology. The Bayes factor is taken as a criterion for testing homogeneity of covariance matrices in LDA model. It is noted that the effect of an observation over the criterion is fully explained by the diagnostic measure. We suggest a graphical method that can be taken as a tool for interpreting the diagnostic measure and detecting influential observations. Performance of the measure is examined through an illustrative example.