• 제어로봇시스템학회:학술대회논문집
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• 1996.10b
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• pp.628-631
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• 1996

This paper proposes a surface recognition algorithm which determines the types of contact surfaces by fusing the information collected by the multisensor system, consisted of the optical tactile and force/torque sensors. Since the image shape measured by the optical tactile sensor system, which is used for determining the surface type, varies depending on the forces provided at the measuring moment, the force information measured by the f/t sensor takes an important role. In this paper, an image contour is represented by the long and short axes and they are fuzzified individually by the membership function formulated by observing the variation of the lengths of the long and short axes depending on the provided force. The fuzzified values of the long and short axes are fused using the average Minkowski's distance. Compared to the case where only the contour information is used, the proposed algorithm has shown about 14% of enhancement in the recognition ratio. Especially, when imposing the optimal force determined by the experiments, the recognition ratio has been measured over 91%.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.10a
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• pp.672-675
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• 1997

This paper presents the identification of rotor dynamic parameters. The solution of the system equation can be obtained using least square method. The sensitivity analysis is performed to extract optimized solution, which is considered to be insensitive to inherent measurement errors. The cosine and sine term of orbit shapes can be obtained by experiment the orbit analysis at a different speed after doing orbit analysis at an arbitrary selected speed. This values measured time domain used to search the stiffness and damping coefficients of rotor bearing.

• Journal of KSNVE
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• v.9 no.1
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• pp.97-102
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• 1999

Structure-borne noise is an important aspect to consider during the design and development of a vehicle. In this work. it was desired to identify the primary paths associated with structure-borne noise generated from the engine and front suspension. An experimental source-path-receiver model was used to characterize the system. A variety of primary sources such as engine. tires or exhaust system generate vibrations of the inner surfaces of the passenger compartment of a vehicle which subsequently radiate noise. The source was characterized by the force acting at the engine-to-body interface. and the path was characterized by pressure over force FRF's. The excitation forces were indirectly determined using dynamic stiffness of rubber mount or the system accelerance matrix. Through these analysis, path contribution diagram which is well expressed primary noise path is obtained.

• Structural Engineering and Mechanics
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• v.53 no.2
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• pp.373-392
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• 2015

In the present work, structural joints have been modeled as a pair of translational and rotational springs and frequency equation of the overall system has been developed using sub-structure synthesis. It is shown that using first few natural frequencies of the system, one can obtain a set of over-determined system of equations involving the unknown stiffness parameters. Method of multi-linear regression is then applied to obtain the best estimate of the unknown stiffness parameters. The estimation procedure has been developed first for a two parameter joint model and then for a three parameter model, in which cross coupling terms are also included. Two cases of structural connections have been considered, first with a cantilever beam with support flexibility and then a pair of beams connected through lap joint. The validity of the proposed method is demonstrated through numerical simulation and by experimentation.

• Journal of Electrical Engineering and Technology
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• v.12 no.3
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• pp.1038-1045
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• 2017

To address mounting concerns over global warming, the Paris Agreement was reached in December 2015, which aims to limit the increase in global average temperature. South Korea has set a highly ambitious target to reduce emissions and submitted an Intended Nationally Determined Contribution (INDC). Based on the INDC, we investigated the impact of limiting carbon emissions on the power system and the electricity market in Korea. Through detailed simulations on assumed plausible scenarios, this work highlights a) the effects of different carbon emission targets on the annual carbon emission volumes, generation costs, and carbon price; b) the generation mix changes induced by carbon emission limits; and c) the difference in system marginal price and payments for generator owners that carbon emission constraint creates in electricity markets under three different pricing rules.

• Journal of the korean Society of Automotive Engineers
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• v.13 no.1
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• pp.35-45
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• 1991

A linear quarter model of a vehicle suspension system is built and simulated. Especially the so-called sensitivity analysis is conducted in order to show its applicability to design problems, and sensitivity function is determined in the frequency domain. The change of frequency response function is predicted, which depends on the design parameter variation and the property is verified by computer simulation. Typical performance measures, namely, sprung mass acceleration, suspension deflection, and tire deflection are examined. The vehicle model is analyzed for ist performance sensitivity as a function of the system's feedback gains. The variable feedback gains are selected as the spring and damping coefficients. Frequency response, RMS response, and performance index of the performance evaluation variables are considered and three-dimensional and contour plots of response surfaces are formed to examine output sensitivity to suspension feedback. Performance trade-offs over the entire frequency spectrum are identified from the FRF, and that between ride quality and handling characteristics are examined from the RMS responses.

• Journal of the Korean Society for Precision Engineering
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• v.20 no.3
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• pp.112-119
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• 2003

This paper presents the identification of rotor dynamic parameters. The solution of the system equation can be obtained using least square method. The sensitivity analysis is performed to extract optimized solution, which is considered to be insensitive to inherent measurement errors. The cosine and sine term of orbit shapes can be obtain ed through the by experiment of the orbit analysis at a different speed after doing orbit analysis at an arbitrary selected speed. This values measured time domain are used to search the stiffness and damping coefficients of rotor bearing.

• Korean Journal of Veterinary Service
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• v.45 no.4
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• pp.293-304
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• 2022

Among several diseases of calves, diarrhea is the most prevalent disease and has been a major cause of economic loss to the cattle industry. The main etiologic agents of diarrhea in calves are bacteria, viruses, and protozoa, but non-infectious factors including foreign bodies obstruction in the digestive system also focused as the cause of calf diarrhea in the recent days. Because there is still limited information for foreign body-related diarrhea in calves, especially in Hanwoo, the present retrospective study reviewed the medical records for diarrheic calves with foreign body in the digestive system (n=32). The morbidity was determined as 3.03% and more than half of them presented the acidosis, hyponatremia, and azotemia. The mortality in laparotomy-operated calves to remove foreign bodies or in non-operated ones was 28% or 85.7%, respectively, implied the importance of aggressive decision for laparotomy when the foreign bodies were determined in the digestive system in diarrheic calves. During laparotomy, trichobezoars (hair balls) and hays were the main foreign bodies and prevalently placed in the abomasum. In the trials to predict prognosis by several clinical factors, the time for laparotomy over 2 days after first diagnosis, acidosis, and foreign body in the abomasum were highly associated with mortality. Therefore, we believe that prompt surgical procedure (laparotomy) is necessary upon obstruction in the digestive system by foreign bodies is tentatively diagnosed in the diarrheic calf. In addition, when differential diagnosis list is made, foreign body-related diarrhea is necessary to be included in case of diarrheic calf.

• The Journal of Fisheries Business Administration
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• v.24 no.1
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• pp.29-44
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• 1993

The Purpose of this study is to consolidate the management status of Saggoson in the Choson period by literature research, and examined latest status by field investigation. During the Choson period, there were fish distributors such as Saggoson and Kakju. Saggoson took charge of fish distribution from the fishing ground to the land, and handed over the fish to Kakju who sold over them to the whole country: This distibution system of fish was started from and adapted to the yellow-corvenia fishery of Westhern Sea. There were two resons far this. One was that these fish were. caught much from vast fishing grounds and had a very strong demand, for which professional disributors were needed. The thor was that because fishermen had very limited capital, they had to supply the money for fish production from capitalists like Kakju whom they agreed to sell fish directly to. By this time, it was thought that the fish distibution system for the Westhern Sea fishery was determined by the background and tradition. Meanwile, Saggoson, which has been working far a long time in Westhern Sea, is placed in changing circumstances. That is, small scale fishery Saggoson deals with will be getting fewer, because the big scale reclamation projects in this area threatens the fishery's existence. Also, Saggoson, presently, might be forced to become more efficient in its distribution in the future. In this situation, the management status of a Sggoson in the past and present needs to be consolidated and investigated through this study.

• Journal of Power System Engineering
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• v.5 no.3
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• pp.80-87
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• 2001

Decorative properties of chromium depositions from oxalic acid bath containing chromium oxide and ammonium sulfate have been examined over a wide range of bath compositions and plating conditions. The obtained results from this experiment are summarized as follow: The followings were determined as a optimum conditions, bath compositions; $CrO_3\;200{\sim}250\;g/{\ell},\;H_2C_2O_4{\cdot}2H_2O\;500{\sim}700\;g/{\ell},\;(NH_4)_2SO_4\;40{\sim}120\;g/{\ell}$, and operation conditions; pH $2.0{\sim}2.5$, current density $15{\sim}250\;A/dm^2$ at bath temperature range of $30{\sim}80^{\circ}C$. Bright chromium deposits were obtained over a wide range of ammonium sulfate concentration and bath temperature. Decorative property for chromium deposition was adopted to apply stoichiometric ratio of $CrO_3$ concentration and $H_2C_2O_4{\cdot}2H_2O$.