• Journal of the Korea Institute of Information Security & Cryptology
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• v.31 no.3
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• pp.401-410
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• 2021

Recently, as cyber attacks targeting industrial control systems increase, various studies are being conducted on the detection of abnormalities in industrial processes. Considering that the industrial process is deterministic and regular, It is appropriate to determine abnormality by comparing the predicted value of the detection model from which normal data is trained and the actual value. In this paper, HAI Datasets 20.07 and 21.03 are used. In addition, an ensemble model is created by combining models that have applied different time steps to Gated Recurrent Units. Then, the detection performance of the single model and the ensemble recurrent neural networks model were compared through various performance evaluation analysis, and It was confirmed that the proposed model is more suitable for abnormal detection in industrial control systems.

• Journal of the Korea Society of Computer and Information
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• v.27 no.10
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• pp.123-130
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• 2022

In this paper is one of the measures to prevent concrete collapse accidents at construction sites in advance. Analyzed based on accumulated Meteorological Agency data. It is a reliable model that confirms the prediction of the decrease rate occurrence interval, and the verification items such as p_value is 0.5 or less and ecof appears in one direction through the SARIMA model, which is suitable for regular and clear time series data models, ensure reliability. Significant results were obtained. As a result of analyzing the temperature change by time zone and the water reduce ratio by section using the data secured based on such trust, the water reduce ratio is the highest in the 29-31 ℃ section from 12:00 to 13:00 from July to August. found to show. If a factor in the research result interval occurs using the research results, it is expected that the batch plant will produce Ready-mixed concrete that reflects the water reduce ratio at the time of designing the water-cement mixture, and prevent the decrease in concrete compressive strength due to the water reduce ratio.

• Design & Manufacturing
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• v.16 no.4
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• pp.52-59
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• 2022

Currently, Korea is an aging society and is expected to become a super-aged society in about four years. X-ray devices are widely used for early diagnosis in hospitals, and many X-ray technologies are being developed. The development of X-ray device technology is important, but it is also important to increase the reliability of the device through accurate data management. Sensor nodes such as temperature, voltage, and current of the diagnosis device may malfunction or transmit inaccurate data due to various causes such as failure or power outage. Therefore, in this study, the temperature, tube voltage, and tube current data related to each sensor and detection circuit of the diagnostic X-ray imaging device were measured and analyzed. Based on QC data, device failure prediction and diagnosis algorithms were designed and performed. The fault diagnosis algorithm can configure a simulator capable of setting user parameter values, displaying sensor output graphs, and displaying signs of sensor abnormalities, and can check the detection results when each sensor is operating normally and when the sensor is abnormal. It is judged that efficient device management and diagnosis is possible because it monitors abnormal data values (temperature, voltage, current) in real time and automatically diagnoses failures by feeding back the abnormal values detected at each stage. Although this algorithm cannot predict all failures related to temperature, voltage, and current of diagnostic X-ray imaging devices, it can detect temperature rise, bouncing values, device physical limits, input/output values, and radiation-related anomalies. exposure. If a value exceeding the maximum variation value of each data occurs, it is judged that it will be possible to check and respond in preparation for device failure. If a device's sensor fails, unexpected accidents may occur, increasing costs and risks, and regular maintenance cannot cope with all errors or failures. Therefore, since real-time maintenance through continuous data monitoring is possible, reliability improvement, maintenance cost reduction, and efficient management of equipment are expected to be possible.

• Journal of the Korean Geotechnical Society
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• v.24 no.10
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• pp.131-146
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• 2008

Many attempts have been made to determine the uniaxial compressive strength and elastic modulus of regular specimens of rock indirectly. But little experimental work has been done to find above two parameters using Brazilian test value up to date. This paper employs Brazilian test value to estimate uniaxial compressive strength and elastic modulus of sedimentary (sand stone, shale) and metamorphic (gneiss) rocks. High reliability of Brazilian test has been supported by the established conclusions drawn from point load test and Schmidt hammer strike values. It has also been found that this method can be applied easily and rapidly to the estimation of uniaxial compressive strength and elastic modulus of rock cores when direct tests are not available.

• Korean Journal of Poultry Science
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• v.7 no.2
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• pp.37-46
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• 1980

Hand deboned and mechanically deboned chicken meat were produced from domestic broilers and spent layers. Meat yield, chemical composition, functional characteristics, stability during storage, and microbiological properties were investigated Chicken patties and frankfurters were also manufactured by varying the relative proportion of MDCM to HDCM as raw materials, ana their palatability, shelf-life and textural properties were evaluated. The obtained results were as follows: 1) 35% of carcass wt was recovered as HDCM and 45% as MDCM, total meat yield reaching 80% of carcass wt. 2) Moisture, protein, fat, ash and Ca content of MDCM were 65, 12, 20, 1.7 and 0.2-0.4%,respectively. MDCM was higher in fat, ash and Ca, but significantly lower in moisture and protein. Total pigment content of MDCM was 2.5 times higher than that of HDCD such high content being attributed to the increased inclusion of hemoglobin. 3) The emulsifying capacity (ES) of MOCM per g meat was only 70% that of HDCM. but when ES was expressed on unit g of protein basis MDCM showed even higher ES than HDCM primarily due to tile higher proportion of salt soluble protein fraction. 4) Since the TBA values of MDCM increased rapidly after 4 weeks of frozen storage at -20$^{\circ}C$, the maximum possible storage period of MDCM is estimated to be about 4 weeks. 5) Total microbial counts of MDCM was approximately 1.8${\times}$10$\^$6/g/, showing no great difference from HDCM or red meat. 6) Chicken patty containing MDCM showed gradual increase in TBA value during frozen storage, but its storage up to 8 weeks presented no problems in flavor stability. 7) Color score an4 total palatability of chicken Patty were best for the product containing 30% MDCM. It was also concluded that MDCM can be included in the patties up to 50% of total meat with good results, but more than 70% was not recommended 8) The formulation of MDCM up to 50% in frankfurter gave quite satisfactory acceptability and textural properties comparable to frankfurter made of 100% MDCM, but the inclusion of more than 70% MDCM was not recommended 9) The TBA value of frankfurter containing MDCM did not increase to any great extent until 4 weeks of storage at 4$^{\circ}C$, indicating no unique problems in flavor instability compared to regular frankfurter. 10) It was concluded that processed meat products such as patties and frankfurters containing MDCM up to 30-50% of total meat ingredients gave satisfactory results in color, texture and palatability, comparable to regular products.

• Archives of Pharmacal Research
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• v.10 no.1
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• pp.60-66
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• 1987

A procedure utilizing high pressure liquid chroatography coupled with UV detection is described for the determination of blood concentration of higenamine. Deproteinized serum was pretreated with$C_{18}$(Sep-pak $C_{18}$ cartridge) and the 70% EtOH eluent was applied onto a reversed-phase column ($\mu$ Bondapak $C_{18}]$) with a 15% acetonitrile in 0.05 N $NaH_2$$PO_4$-trichloroacetic acid mixed buffer (pH 2.8) as a mobile phase. With the UV detection at 232 nm, the retention times of higenamine and 1, 2, 3, 4-tetrahydropapaveroline, an internal standard, were 5.2 min and 3.9 min respectively. The blood concentration of higenamine was meausred at regular intervals after i. v. injection of higenamine to rabbit. A drastic decrease in higenamine concentration to 30% of the maximum value obtained immediately after the injection, was observed during the first 1-2 min period and thereafter the rate of decrease was slowed down. The analytical result seemed to coincide with the pharmacological effect of higenamine exerting the maximum chronotropic and hypotensive effect at the completion of the injections which were progressively recovered.

• Journal of Power Electronics
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• v.14 no.1
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• pp.105-114
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• 2014

The sliding mode control (SMC) strategy is applied to a permanent magnet synchronous machine vector control system in this study to improve system robustness amid parameter changes and disturbances. In view of the intrinsic chattering of SMC, a current sliding mode control method with a load sliding mode observer is proposed. In this method, a current sliding mode control law based on variable exponent reaching law is deduced to overcome the disadvantage of the regular exponent reaching law being incapable of approaching the origin. A load torque-sliding mode observer with an adaptive switching gain is introduced to observe load disturbance and increase the minimum switching gain with the increase in the range of load disturbance, which intensifies system chattering. The load disturbance observed value is then applied to the output side of the current sliding mode controller as feed-forward compensation. Simulation and experimental results show that the designed method enhances system robustness amid load disturbance and effectively alleviates system chattering.

• Journal of the Korean Electrochemical Society
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• v.13 no.4
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• pp.235-239
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• 2010

The $Li_4Ti_5O_{12}$/CNT composite is prepared by ultrasound associated sol-gel method. The prepared composite is characterized by SEM, TEM, XRD and TG analysis, and their electrochemical behaviors are investigated by cyclic voltammetry, electrochemical impedance spectroscopy and charge-discharge test in 1M $LiBF_4$/PC electrolyte. From the results, it is identified that the $Li_4Ti_5O_{12}$ nanoparticles coated on CNT surface have regular size with around 10~30 nm and spinel-framework structure. At the current rate of 20C, the discharge capacities of $Li_4Ti_5O_{12}$/CNT composites with CNT contents of 15, 30 and 50 wt% are 57, 63 and $48mAhg^{-1}$, respectively, which have similar value. The improved electrochemical behavior of the $Li_4Ti_5O_{12}$/CNT composite electrode is attributed to the addition of CNT with electronic conductivity.

• Proceedings of the KSPS conference
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• 1996.02a
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• pp.79-84
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• 1996

The two existing romanization systems in Korea, namely the recently promulgated Ministry of Education version sponsored by the National Academy of Sciences incorporating for the most part the McCune-Reischauer system and the Hangeul Haghoe or the Korean Language Society's version, must be judged as failures: He fennel for its disregard of Korean orthography and pronunciation, use of Latin-oriented pronunciation despite its assertion that English is the standard used, and the greatest weakness of all, its use of phonetic symbols neither found in regular typewriters, teleprinters, word processors and telex machines nor understood by laymen, sometimes not even by specialists. And the latter suffers from its undue emphasis on Korean orthography, Latin-oriented pronunciation being only partly capable of representing Korean pronunciation, among other shortcomings. Since the two existing romanization systems of Korean in South Korea, and romanization system of Japanese with Latin-oriented pronunciation are woefully inadequate, in today's world where English is used as if it were the international language almost all over the world, the present writer has invented a completely new system of romanizing Korean and Japanese by the so-called pseudo-phonetic method. This method employs the roman letters only and uses thorn in place of phonetic symbols as long as the letters thus applied are believed to have constant sound value. The English pronunciation is the standard used for this system.

• Journal of Environmental Health Sciences
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• v.34 no.1
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• pp.95-100
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• 2008

An automatic titration system using a PC-camera with a color filter on its lens was used in the $KMnO_4$ consumption test of tap water and distilled water in relation to blank tests. The very faint pink color of titration end point could be effectively detected by using a yellow cellophane paper as a color filter. The average hue value (Havg) of 192 pixels in the image of the sample solution being titrated was computed and followed up at regular time intervals during titration in order to detect the titration end point. The Havg decrease of 2 degrees from the average of first 10 Havgs was regarded as reaching the end point. The volume of 0.01N $KMnO_4$ consumed by a tap water sample was $0.728{\pm}0.022ml$ in manual titration and $0.735{\pm}0.013ml$ in automatic titration (p=0.580). The volume of 0.01N $KMnO_4$ consumed by a distilled water sample was $0.383{\pm}0.015ml$ in manual titration and $0.367{\pm}0.015ml$ in automatic titration (p=0.252). The high p-values for t-test suggested that there were good agreements between manual and automatic titration data and the automatic method proposed in this article was considered to effectively replace the manual titration.