• Title/Summary/Keyword: normal operation

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COMS Normal Operation for Earth Observation Mission

  • Cho, Young-Min
    • Korean Journal of Remote Sensing
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    • v.29 no.3
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    • pp.337-349
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    • 2013
  • Communication Ocean Meteorological Satellite (COMS) for the hybrid mission of meteorological observation, ocean monitoring, and telecommunication service was launched onto Geostationary Earth Orbit on June 27, 2010 and it is currently under normal operation service on $128.2^{\circ}$ East of the geostationary orbit since April 2011. In order to perform the three missions, the COMS has 3 separate payloads, the meteorological imager (MI), the Geostationary Ocean Color Imager (GOCI), and the Ka-band antenna. The MI and GOCI perform the Earth observation mission of meteorological observation and ocean monitoring, respectively. For this Earth observation mission the COMS requires daily mission commands from the satellite control ground station and daily mission is affected by the satellite control activities. For this reason daily mission planning is required. The Earth observation mission operation of COMS is described in aspects of mission operation characteristics and mission planning for the normal operation services of meteorological observation and ocean monitoring. And the first one-year normal operation results after the In-Orbit-Test (IOT) are investigated through statistical approach to provide the achieved COMS normal operation status for the Earth observation mission.

A Comparative Study on Start-up and Normal Operation Data for Phosphorus Removal in WWTPs (인 처리시설 시운전 및 정상운전 자료 비교·분석 연구)

  • Yun, Soyoung;Ryu, Jaena;Kim, Jonguk;Oh, Jeill
    • Journal of Korean Society of Water and Wastewater
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    • v.27 no.1
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    • pp.113-120
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    • 2013
  • This study aimed to obtain quantitative data for WWTP operators in phosphorus removal process. This was done by reviewing and comparing phosphorus removal efficiency(%), coagulants dosage(Al/P and $Al_2O_3$(mg/L)), sludge production($kg/m^3$), and operation cost($won/m^3$) of start-up and normal operation data. Phosphorus removal efficiency of all tertiary treatment process was up to 70 ~ 89 % in start-up and normal operation. Average molar ratio(Al/P) was similar as 5 in both operations, but average coagulants dosage (mg/L) of start-up (8.5 mg/L) was higher than normal operation (6.2 mg/L). Average operation cost was higher for start-up ($33.6won/m^3$) than normal operation ($28.4won/m^3$), while electricity cost required for the normal operation ($9.0won/m^3$) was higher by $3.5won/m^3$.

A Study on the Electrical and Heat Generation Characteristics of an Induction Motor under Restrained Operation (유도전동기의 구속운전에 따른 전기 및 발열 특성 연구)

  • Jong-Chan Lee;Doo-Hyun Kim;Sung-Chul Kim
    • Journal of the Korean Society of Safety
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    • v.38 no.1
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    • pp.25-33
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    • 2023
  • In this study, we determined the failure rate and fire status of electric motors widely used in domestic and industrial devices and analyzed the associated fire risks by identifying the electrical and temperature characteristics of electric motors under the normal and restrained operation modes in industrial sites and laboratories. A 2.2kW motor used for driving a conveyor during the vulcanization process in a rubber product manufacturing plant was employed as the study object and was exposed to a high- temperature environment as this motor is widely used in industrial sites. The current amplitude was 4.45-4.50 A during normal operation and 38.2-41.5 A during restrained operation due to the pinching of products and semi-finished products (i.e., 8.5 times higher than that during normal operation). The leakage current amplitude was 0.33 mA during both operation modes. The temperature of the workplace in summer was 42.38℃, indicating a poor environment for the installed motor. In the laboratory, the current and temperature of the coil inside a 3.7kW motor were measured under the restrained operation mode as performing measurements of the coil inside the motor in industrial sites is challenging. The current amplitude during normal operation was 3.5 A, whereas that during restrained operation for 30 s was 51.7-58.6 A, which is 14.8-16.7 times higher than that of normal operation. Moreover, the temperature of the motor coil increased from 22.9℃ to 101℃. Based on the experimental data, we derived the temperature increase formula according to the restrained operation time by performing a regression analysis and verified the time at which the temperature exceeded the stipulated limit for the insulation grade. The findings presented in this paper can be utilized to establish fire-prevention measures and perform safety management of motors of the same type or with a similar capacity.

A Study on the Necessity in Establishment of STEL of Dimethylformamide (DMF) - on the focus of the exposure in synthetic leather factories - (디메틸포름아미드(DMF)에 대한 단시간 노출기준 설정의 필요성에 관한 연구 -합성피혁사업장 중심으로-)

  • Lee, Sun Woo;Kim, Tae Hyeung;Kim, Jung Man
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.18 no.1
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    • pp.80-90
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    • 2008
  • This study was carried out to investigate the correlation of urinary NMF concentration in workers exposed to DMF and concentration of DMF in the workplace. Samples were collected in workers exposed to high dose solvent in the synthetic leather factory by using silicagel tubes for 5-15 minutes, and were analyzed by GC. Geometric mean concentrations of DMF in the workplaces were 4.67 ppm in normal operation and 63.95 ppm in high exposure operation. The concentration of case uppers and machine cleaning process were more than 100 ppm in short time. The correlation of urinary NMF in workers and DMF in workplace was statistically significant in normal operation and high exposure operation. Correlation coefficient are 0.215(p<0.05) and 0.263(p<0.05). The result implied that STEL of DMF should be established in normal operation processes as well as high exposure operation processes.

A Clinical Study on the Changes of Serum Enzymes after Open heart Surgery under Cardiopulmonary Bypass (인공심폐기를 이용한 개심술후 혈청효소 변화에 관한 연구)

  • 고재웅
    • Journal of Chest Surgery
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    • v.22 no.4
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    • pp.562-572
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    • 1989
  • The changes of serum glutamic oxaloacetic transaminase [SGOT], serum glutamic pyruvic transaminase [SGPT], serum lactic dehydrogenase [LDH] and serum creatine phosphokinase [CPK] were examined during and after the open heart surgery. In the total of 52 patients with heart diseases including 40 cases of congenital heart anomalies and 12 cases of acquired valvular heart diseases who undergone open heart surgery under cardiopulmonary bypass. The results obtained are as follows: 1. The average value of SGOT before surgery was 30.27 [ 18:86 units. The enzyme was reached to the maximum of 139.88 [ 89.43 units on the 1st day after the operation [p< 0.05], the enzyme activity was gradually decreased from the 3rd day after the operation, returned to the normal range on the 7th day after the operation. 2. The average value of SGPT before surgery was 14.36 [ 7.45 units. The enzyme was reached to the maximum of 34.67 [ 27.64 units on the 2nd day after the operation, but it was valueless statistically, the enzyme activity was gradually decreased from the 3rd day after the operation, returned to the normal range on the 5th day after the operation. 3. The average value of LDH before surgery was 263.07 * 86.66 units. The enzyme was reached to the maximum of 662.29 * 303.60 units on the 2nd day after the operation [p < 0.05], the enzyme activity was gradually decreased from the 5th day after the operation, returned to the normal range on the 7th day after the operation. 4. The average value of CPK before surgery was 141.35 * 43.44 units. The enzyme was reached to the maximum of 377.42 [ 222.02 units on the 1st day after the operation [p < 0.05], the enzyme activity was gradually decreased from the 5th day after the operation, returned to the normal range on the 7th day after the operation. 5. In the relationships of the serum enzymes and duration of the extracorporeal circulation, the values on the group over 90 minute of the extracorporeal circulation were increased than on the group below 90 minute of the extracorporeal circulation, but it was valueless statistically.

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Characteristics of the Mission Planning for COMS Normal Operation (천리안위성 정규 운영에 대한 임무계획 특성)

  • Cho, Young-Min;Jo, Hye-Young
    • Aerospace Engineering and Technology
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    • v.12 no.2
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    • pp.163-172
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    • 2013
  • Communication Ocean Meteorological Satellite (COMS) has the hybrid mission of meteorological observation, ocean monitoring, and telecommunication service. The COMS is located at $128.2^{\circ}$ East longitude on the geostationary orbit and currently under normal operation service since April 2011. For the sake of the executions of the meteorological and the ocean mission as well as the satellite control and management, the satellite mission planning is daily performed. The satellite mission plans are sent to the satellite by the real-time operation and the satellite executes the missions as per the mission plans. In this paper the mission planning for COMS normal operation is discussed in terms of the ground station configuration and the characteristics of daily, weekly, monthly, and seasonal mission planning activities. The successful mission planning is also confirmed with the first one-year normal operation results.

A Study on the Observer Training and Implementation for Effective Normal Operation Safety Survey (NOSS)

  • Choi, Jin-Kook;Choi, Se-Jong
    • Journal of the Korean Society for Aviation and Aeronautics
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    • v.29 no.2
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    • pp.111-116
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    • 2021
  • Normal Operation Safety Survey (NOSS) is a safety management tool used by air traffic control organizations to measure data related to threats and errors to proactively prevent accidents before they occur. NOSS was developed to be applied to the air traffic control field according to the concept of Line Operation Safety Audit (LOSA) conducted by airlines to reduce human errors in the cockpits. Safety management based on data is crucial for the prevention of control-related accidents, and the competency of observers for this is important for the successful implementation of NOSS. Based on LOSA implementation experiences and expert interviews, this paper introduces the international NOSS methods and discusses the key factors required for effective observation and the implementation methods and implications of NOSS observer training.

A Clinical Study on SGOT,SGPT and LDH in the Patients of Open Heart Operation with Cardiopulmonary Bypass (개심술환자의 혈청효소치 변동에 관한 연구)

  • Park, Kang-Sik;Jee, Heng-Ok;Kim, Kun-Ho
    • Journal of Chest Surgery
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    • v.15 no.1
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    • pp.46-52
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    • 1982
  • Activities of serum glutamic pyruvic transaminase [SGPT], serum glutamic oxaloacetic transaminase [SGOT] and serum lactic dehydrogenase [LDH] were determined during and after surgery In a total of 18 patients with heart diseases Including 8 cases of congenital heart anomaly and 10 cases of acquired valvular diseases who undergone open heart surgery under cardiopulmonary bypass. The results obtained are as follows: 1]The average value of the activity of SGPT before the surgery was $27.94{\pm}12.24$ units. The value was increased following the operation and reached to the maximum value of $43.83{\pm}37.02$ units 2 days after the operation, which was slightly deviated from the normal range. The enzyme activity returned to the normal range of $32.82{\pm}23.61$ units 4 days after the operation. 2]The average value of the activity of SGOT before the surgery was observed to be $30.5{\pm}11.29$ units. The value increased during the operation and reached to the maximum value of $95.56{\pm}43.38$ units. 2 days after the operation, the enzyme activity was gradually decreased thereafter and returned to the normal range 6 days after the operation. 3]The average value of the activity of serum LDH before the surgery was found to be $258.0{\pm}88.96$ units. The value was increased during the operation and reached to the maximum value of $930.55{\pm} 258.23$ units 2 days after the operation. The enzyme activity was gradually decreased thereafter and returned to normal range 7 days after the operation. 4]It was observed that the longer the time required for the extracorporeal circulation in the open heart surgery became, the greater the changed in activity of SGOT, SGPT and serum LDH were found.

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Safety Evaluation of Elevated Guideway during Abnormal Operation on LRT of Driverless Automatic Driving System (무인자동운전 경전철시스템 고가교량의 비상운전 중 안전성평가)

  • Son Eun-Jin;Kim Min-Soo;Lim Young-Su;Lim Jong-Pil
    • Journal of the Korean Society for Railway
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    • v.9 no.1 s.32
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    • pp.29-35
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    • 2006
  • Trains in LRT(Light Railway Transit) system usually have shorter car length than metro's because of their smaller passensers demand. Therefore it is very likely that the load condition of LRT system in abnormal operation, in case of which trains are in close proximity by system broke or train rescue works, could be worse rather than in normal operation, in spite of rare probability of abnormal operation. In this study, the target reliability indexes of several abnormal operations are estimated in accordance with the occurrence probabilities of each abnormal operation case and the reliability index of normal operation presented by the specification. From the indexes, load factors for the abnormal operation cases are estimated and the safety evaluation is performed for Yong-in LRT project.

The Power Flow Control of UPFC for Cost Minimization

  • Lim, Jung-Uk;Moon, Seung-Il
    • KIEE International Transactions on Power Engineering
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    • v.12A no.1
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    • pp.31-35
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    • 2002
  • This paper presents a new operation scheme of UPFC to minimize both generation costs and active power losses in a normal operation state of power system. In a normal operation, cost minimization is a matter of primary concern among operating objectives. This paper considers two kinds of costs, generation costs and transmission losses. The total generation cost of active powers can be minimized by optimal power flow, and active power losses in the transmission system can be also minimized by power flow control of UPFC incorporated with minimization of generation costs. In order to determine amounts of active power reference of each UPFC required for the cost minimization, an iterative optimization algorithm based on the power flow calculation using the decoupled UPFC model is proposed. For verification of the proposed method, intensive studies have been performed on a 3-unit 6-bus system equipped with a UPFC.