• Electronics and Telecommunications Trends
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• v.8 no.3
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• pp.39-52
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• 1993

This study involves a Common Cause Failure (CCF) problem on the ultra-high reliability required system development such as war game operations, nuclear power control, air traffic control, space shuttle missions, and large scale network communication system. The system situation problems are defined according to CCF, reliability and system fault identifications for the development cast verifications in the multi-version redundant software system. Then, CCF analysis of redundant system, system principles and statistical dependence are also described. This validation oh the CCF in the human software interaction system will notify software engineers to conceive what really is CCF contribution factor, not only the internal but the external ones.

• The Korean Journal of Nuclear Medicine Technology
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• v.15 no.1
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• pp.45-50
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• 2011

Purpose: It appears the different value when the injection dose is calculating for patients on each PET/CT systems. It directly affects the technologists' radiation exposed dose. We studied the effect of the variable injection doses from several PET/CT systems to exposure dose for technologists. Materials and Methods: Six technologists have worked for 5 months through unit rotations with 3 PET/CT systems {Scanner 1 (S1): 0.15 mCi/kg, Scanner 2 (S2): 0.17 mCi/kg, Scanner 3 (S3): 0.12 mCi/kg}. Eighteen to 19 patients have had examinations per a day on each PET/CT systems. Examination parameters were adjusted to the same. TLDs were used for checking the exposure dose of technologists. Results: Each technologists' the monthly average exposure dose was as follows; S1: 0.76 mSv, S2: 0.93 mSv, S3: 0.47 mSv. The maximum exposure dose was 1.12 mSv, and minimum was 0.42 mSv. The results showed significance in the correlation between the PET/CT system and the exposure dose (p<0.005). Conclusion: When the amount of injection dose was small, the exposure dose was decreased not only the patients but also the technologists. The exposure dose was decreased by the individual proficiency of technologists. However, the low injection dose can highly reduce the exposure dose for technologist so that there will be needed to following studies.

• Publications of The Korean Astronomical Society
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• v.27 no.3
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• pp.49-59
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• 2012

KASI (Korea Astronomy and Space Science Institute) has developed an SLR (Satellite Laser Ranging) system since 2008. The name of the development program is ARGO (Accurate Ranging system for Geodetic Observation). ARGO has a wide range of applications in the satellite precise orbit determination and space geodesy research using SLR with mm-level accuracy. ARGO-M (Mobile, bistatic 10 cm transmitting/40 cm receiving telescopes) and ARGO-F (Fixed stationary, about 1 m transmitting/receiving integrated telescope) SLR systems development will be completed by 2014. In 2011, ARGO-M system integration was completed. At present ARGO-M is in the course of system calibration, functionality, and performance tests. It consists of six subsystems, OPS (Optics System), TMS (Tracking Mount System), OES (Opto-Electronic System), CDS (Container-Dome System), LAS (Laser System) and AOS (ARGO Operation System). In this paper, ARGO-M system structure and integration status are introduced and described.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.62 no.3
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• pp.431-436
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• 2013

A neutral section is installed around feeding substation(SS) and sectioning post(SP) that M phase and T phase are isolated in AC feeding system. Electric Train under "Notch-OFF" is operated by inertia within the neutral section. It causes disturbing the operation of electric trains for speed drop and driver's mistakes. A automatic changeover system with thyristor recently have taken under development. In the paper, it is introduced the configuration of train detection system and performance testing on automatic changeover system..

• Korean Journal of Remote Sensing
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• v.38 no.5_3
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• pp.979-989
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• 2022

We examined changes in the shell valve movements (SVMs) of Mytilus edulis and Crassostrea gigas using a Hall element sensor to investigate the early detection of the toxic dinoflagellate Alexandrium pacificum. No increase or decrease was observed in SVMs caused by the non-toxic algae Isochrysis galbana in both M. edulis and C. gigas. However, when M. edulis and C. gigas were exposed to A. pacificum, which causes paralytic shellfish poisoning, the average SVMs for 12 hours before and after exposure increased from 1.25 times/hr to 2.13 times/hr and 2.23 times/hr to 8.91 times/hr, respectively. After exposure to A. pacificum, the SVMs of M. edulis increased rapidly within 1 hour and then decreased gradually. However, C. gigas showed high SVMs until 4 hours after exposure. SVMs of C. gigas appeared to be more sensitive to toxic dinoflagellate than those of M. edulis. Therefore, these results are expected to be used as basic data for the establishment of a biological monitoring system for early detection of the toxic dinoflagellate A. pacificum.

• Journal of the Korean Association of Geographic Information Studies
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• v.8 no.4
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• pp.44-51
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• 2005

In this study, the method of extracting road centerline's coordinate and road facilities is presented using RC helicopter photogrammetry system. From the survey of extracted road centerline, the errors turned out to be -0.117m ~ 0.103m on the X-axis and -0.014m ~ 0.009m on the Y-axis when RC Helicopter photogrammetry system utilized. By application of this system, hereafter, not only management of road facilities but also construction of DB would be enable which need positioning and design of alignment on the access is not easy area such as traffic congestion or toparchy area.

• Journal of Bio-Environment Control
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• v.13 no.3
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• pp.143-148
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• 2004

The automatic operating system was designed and built to work manless multipurpose in greenhouse. The system proved to be a reliable system for performing multipurpose functions. Its development involved the integration of moving part, height control part, watering part, ventilation part and inhalation part. The moving part was able to be moved it on the rail installed in greenhouse, the height control part controled it up and down by height of the crops, the watering part sprinkled a agricultural medicines on the crops and the ventilation and the inhalation part ventilated and inhaled different thing and vermin which were attached on crops. Based on the results of this study the following conclusions were made: The moving velocity was changed 0.047 - 0.027 m/s by the dial transfer. The velocity within 50 cm from center of the entrance was 0.2 m/s. The watering volume of spray increased as the pressure of spray was high. The difference of spray pressure between 10 kg/$\textrm{cm}^2$ and 15 kg/$\textrm{cm}^2$ was 60 ml, but that of spray pressure between 15 kg/$\textrm{cm}^2$ and 20 kg/$\textrm{cm}^2$ was 20 ml. The average speed of a current of inhalation was 3.64 m/s and the inhalation flux of inhalation was measured 0.044 ㎥/s by using glues seed and styrofoam.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.3
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• pp.356-362
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• 2010

When pine (Pinus densiflora) needles were fractionated into cold water (PD-CW), hot water (PD-HW) and methanol extract (PD-M), PD-M showed potent simulating activity (1.19-fold of the saline control) for proliferation of bone marrow cells mediated by Peyer's patch cells in vitro. MeOH extracts were prepared by homogenization, stirring or reflux to identify the method of methanol extraction, and MeOH extract by reflux method showed significantly highest intestinal immune system modulating activity (1.30-fold) in vitro. The intestinal immune system modulating effect of orally administered PD-M fractionated from pine needles also were studied in mice. Analyzing intestinal immune system modulating activity mediated Peyer's patch cells from C3H/He mice which had been fed with PD-M at different doses for 7 days, 1.0 g/kg of BW/day indicated that the bone marrow cells had proliferated (3.65-fold of 3% EtOH administered group). In addition, the amounts of IL-6 in the culture supernatant of Peyer's patch cells at 1.0 g/kg of BW/day were increased (1.13-fold) whereas the production of GM-CSF was not dose dependent. These results indicate that oral administration of PD-M enhances the secretion of hematopoietic growth factors such as GM-CSF and IL-6 from Peyer's patch cells, and these cytokines also act on modulator of bone marrow cell proliferation.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.65 no.4
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• pp.468-476
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• 2020

This study was performed to establish light intensity conditions for producing stem cuttings for aeroponic systems suitable for seed potato production using a closed-type plant production system. Shoot tip cultured plantlets of 'Sumi' and 'Chubaek' potato (Solanum tuberosum L.) were acclimatized, cuttings were collected, and stem cuttings were planted. The seedlings were raised for 40 days at different LED light intensities (60, 120, 180, and 240 μmol·m^-2·s^-1), and were cultivated in an aeroponic system for 80 days. When stem cuttings were raised at 60 μmol·m^-2·s^-1 LED light intensity, the plant height was the longest, at 17.3 cm for 'Sumi' and 16.1 cm for 'Chubaek', and the number of nodes was the highest in both cultivars. The higher light intensities, produced smaller plants with fewer nodes. The leaf areas, SPAD values, and Fv/Fm values differed slightly between cultivars. The fresh weight of stem cuttings, and the production rate of healthy stem cuttings were the highest at 60 μmol·m^-2·s^-1. In the aeroponic system, seedlings raised at 60 μmol·m^-2·s^-1 with LED light intensity showed a difference between the cultivars, but the fresh weight of stems and leaves above the planting plate was the heaviest. In addition, below the planting plate the stem cuttings were longest and the root weight was heaviest at 60 μmol·m^-2·s^-1 LED light intensity. The number of stolons also differed between cultivars, but was greatest for seedlings raised at 60 μmol·m^-2·s^-1 LED light intensity, at 4.2/plant for 'Sumi' and 7.7/plant for 'Chubaek'. At 60 μmol·m^-2·s^-1 LED light intensity, the tuber number and total tuber weight were the best, but the higher the light intensity, the smaller the total tuber number and total tuber weight for both cultivars. In conclusion, when producing potato stem cuttings for aeroponic systems using a closed-type plant production system, the most suitable LED light intensity for raising seedlings was found to be 60 μmol·m^-2·s^-1.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2013.05a
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• pp.429-430
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• 2013