• Transactions of the Korean Society of Mechanical Engineers
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• v.19 no.8
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• pp.2012-2021
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• 1995

An experimental study was performed for the analysis of dynamic characteristics of refrigeration system by controlling the evaporator superheat. Experimental data have been taken utilizing two different devices, thermostatic expansion valve(T.E.V.) and electronic expansion valve(E.E.V.), for the control of the evaporator superheat. The ranges of parameters, such as superheat, mass flow rate of refrigerant and inlet temperature of evaporator were 5-30.deg. C 90-170 kg/h and 10-25.deg. C, respectively. The data taken from the T.E.v.and E.E.v.were discussed with the control of the superheat, pressure drop, refrigerating capacity, compression work, evaporating temperature, condensing temperature and COP affecting performance characteristics of refrigeration system. In case of the refrigerant flow control with T.E..V., the superheat and pressure drop of the evaporator varied periodically, but the control with E.E.V., the parameters were very stable. In E.E.v.control, refrigerating capacity, compression work and evaporating temperature were decreased with increasing superheat, and the highest COP was obtained in the range of superheat from 5.deg. C to 15.deg. C.

• Proceedings of the KIEE Conference
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• 1998.11a
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• pp.100-102
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• 1998

This paper presents technique to control blower at constant air volume rate using V/F Control. Especially, this control method have not pressure sensors to measure because of using torque-speed relation based on the fan laws. Therefore, this technique is very simple and practical.

• Smart Media Journal
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• v.12 no.5
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• pp.73-80
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• 2023

Recently, intelligent control systems are developing rapidly in various application fields, and methods for utilizing technologies such as deep learning, IoT, and cloud computing for intelligent control systems are being studied. An important technology in an intelligent control system is recognizing and tracking objects in images. However, existing multi-object tracking technology has problems in accuracy and speed. In this paper, a real-time intelligent control system was implemented using YOLO v5 and YOLO v6 based on a one-shot architecture that increases the accuracy of object tracking and enables fast and accurate tracking even when objects overlap each other or when there are many objects belonging to the same class. The experiment was evaluated by comparing YOLO v5 and YOLO v6. As a result of the experiment, the YOLO v6 model shows performance suitable for the intelligent control system.

• Biomedical Science Letters
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• v.27 no.4
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• pp.283-290
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• 2021

Severe acute respiratory syndrome coronavirus (SARS-CoV2) is a major coronavirus that infects humans with human Coronavirus (HuCoV)-229E, HCoV-OC43, HCoV-HKU1, HCoV-NL63, Severe acute respiratory syndrome coronavirus (SARS-CoV) and Middle east respiratory syndrome coronavirus (MERS-CoV). SARS-CoV2 is currently a global pandemic pathogen. In this study, we developed conventional RT-PCR based diagnostic system for the detection of SARS-CoV2 which is relatively inexpensive but has high stability and a wide range of users. Three conventional RT-PCR primer sets capable of forming specific band sizes by targeting the ORF1ab [232 nucleotide (nt)], E (200 nt) and N (288 nt) genes of SARS-CoV2 were developed, respectively, and it were confirmed to be about 10~100 times higher detection sensitivity than the previously reported methods. In addition, a standard positive control that can generate specific amplicons by reacting with the developed RT-PCR primers and verify the false-positiv from contamination of the laboratory was produced. Therefore, the diagnostic system that uses the RT-PCR method is expected to be used to detect SARS-CoV2.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2019.05a
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• pp.323-324
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• 2019

For flash memory devices with Ge-MONOS(metal-Oxide-Nitride-Oxide-Silicon) structures, variations of threshold voltage with programming voltage were investigated. The programming voltage was observed in steps of 1V from 10V to 17V and programmed for 1 second. The threshold voltage from 10V to 14V was about 0.5V, which is not much different from that before programing, and the threshold voltages at 15V, 16V and 17V were 1.25V, 2.01V and 3.84V, respectively, which differed 0.75V, 1.49V and 3.44V from that before programing.

• Proceedings of the Korea Association of Crystal Growth Conference
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• 1999.06a
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• pp.361-369
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• 1999

New method of control based upon a physical model of the Stepanov growth technique has been developed. The controller keeps the system stable and completely denies operator's interference into the process. The system demonstrates very reliable results under commercial production of shaped sapphire crystals.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.9 no.4
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• pp.437-440
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• 1999

New method of control based upon a physical model of the Stepanov growth technique has been developed. The controller keeps the system stable and completely denies operator's interference into the process. The system demonstrates very reliable results under commercial production of shaped sapphire crystals.

• Steel and Composite Structures
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• v.49 no.1
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• pp.1-17
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• 2023

Based on Ahmadzadeh-Varvani hardening rule (A-V model), multiaxial ratcheting effect of Z2CND18.12N austenitic stainless steel is simulated by ABAQUS with user subroutine UMAT. The results show that the predicted results of the origin multiaxial A-V model are lower than the experimental data, and it is difficult to control ratcheting strain rate. In order to improve the predicted capability of A-V model, the A-V model is modified. In this study. Moreover, under the assumption of the von Mises yield criterion and normal plasticity flow rule, we develop a numerical algorithm of plastic strain with the improved model to implement the finite element calculation of the model. Internal iteration in the numerical algorithm was implemented with the Euler backward method, which calculated the trial strain for each equilibrium iteration using the consistent tangent matrix. With a user subroutine, the proposed model is programmed into ABAQUS for a user - executable version. By simulating the uniaxial ratcheting of a round bar made of Z2CND18.12N austenitic stainless steel, we observe that the predicted results simulated by ABAQUS with UMAT are compared with the experimental data. The predicted results of the improved multiaxial A-V model are consistent well with the experimental data.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2011.06a
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• pp.284-284
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• 2011

Survivors of accidents in the area to check in. check now people will be direct. To reduce the risk UAV with a camera resolution of the survivors fled afar possible. In addition, a stable control for Kalman filter and PID control was used to Even beginners can easily control the UAV is characteristic.

• Journal of Microbiology and Biotechnology
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• v.22 no.10
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• pp.1423-1431
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• 2012

The inhibitory effect of IgY against Vibrio parahaemolyticus and Vibrio vulnificus responsible for seafood-borne diseases was investigated in this study. Water-soluble fractions (WSF) of protein containing IgYs were isolated from the egg yolk of hens initially immunized with formalin-inactivated V. parahaemolyticus or V. vulnificus. Protein, total and specific IgY contents of the WSF were determined. The inhibitory and protective effects of IgYs on the growth of V. parahaemolyticus and V. vulnificus were assayed in liquid medium and in mice. IgYs showed high affinity to their corresponding antigens with high titer from day 28 onwards. Protein contents and total IgY concentrations remained stable throughout the immunization period, whereas specific IgY concentrations increased steadily and reached a plateau at day 49. Specific IgY powder (150 mg/ml) significantly inhibited further multiplication of both V. parahaemolyticus and V. vulnificus in liquid medium as compared with the control IgY. The bacteria count in mice feces was lower in mice pretreated with specific IgYs than in those pretreated with PBS or control IgY. Higher survival of mice was observed in the experimental groups pretreated with either anti-V. parahaemolyticus (75% survival) or anti-V. vulnificus (87% survival) IgYs, compared with those in the control groups pretreated with PBS or nonspecific IgY. All mice in the control groups died within three days after bacteria inoculation; hence, the protective effect of specific IgYs against infection caused by V. parahaemolyticus and V. vulnificus was demonstrated.