• Journal of Advanced Marine Engineering and Technology
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• v.33 no.5
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• pp.653-661
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• 2009

In order to reduce the noise and oscillation, it is consider a matter in all aspects about the noise stem from accumulator and the characteristic of transmission, Transformation of outside shape has change of noise occurrence at transmission process. Therefore, performed sound numerical analysis and conducted an experiment to examine the birthplace of accumulator's external shape change. In a sound numerical analysis, we can fond out transmission loss between inlet and outlet's sound pressure. In an experiment, we can make out transmission loss by sound wave separation theory through drawing sound pressure inlet and outlet.

• Journal of Biosystems Engineering
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• v.18 no.1
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• pp.37-47
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• 1993

This study was conducted to develop the on-line monitoring system for plant growth responses. The system consisted of two parts. One system was the measuring system and the other was its controlling system. The established measuring systems were the ultrasonic wave sensor driver for height of plant, the potentiometer for diameter of plant stem, and the weighing system with strain gage application for plant weight. Also, computer program for measurement and controlling was developed, and the whole system was tested by the fabricated plant, and the actual plant growth responses were monitored by the system. When monitoring the actual plant growth responses, even the small amount of plant growth resposes could be measured by the system within tolerable error ranges.

• Proceedings of the KSAR Conference
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• 2001.10a
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• pp.25-31
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• 2001

During early development, a dramatic reduction in methylation levels occurs in mouse (Monk et al., 1987). The process of epigenetic reprogramming in early embryos erases gamete-specific methylation patterns inherited from the parents (Howlett ＆ Reik 1991, Monk et al., 1987, Oswald et al., 2000, Sanford et al., 1984). This genome-wide demethylation process may be a prerequisite for the formation of pluripotent stem cells that are important for the later development (Reik ＆ Surani 1997). During post-implantation development, a wave of de novo methylation takes place; most of the genomic DNA is methylated at defined developmental timepoints, whereas tissue-specific genes undergo demethylation in their tissues of expression (Kafri et al., 1992, Razin ＆ Kafri 1994). Another demethylation-remethylation cycle of epigenetic reprogramming takes place during gametogenesis and is necessary for resetting of genomic imprinting (Solter 1988). The dynamic epigenetic reprogramming events appear to be basic and are probably conserved in eutherian mammals (see below). (omitted)

• Journal of Ocean Engineering and Technology
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• v.15 no.1
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• pp.1-6
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• 2001

This study focuses on the potential flow analysis for a hull with the transom stern. The method is based on a low order panel method. The Kelvin type free-surface boundary condition which is known to better fit experimental data for a high speed is applied. To treat a dry transom stern effect a special treatment for the free-surface boundary condition is adopted at the free-surface region after the transom stern. Trim and sinkage, which are important in high speed ships, are considered by an iterative method. Pressure and momentum approaches are used to calculate the wave resistance. Numerical calculations are performed for Athena hull and these results are compared with the experimental data and also other computational results.

• International Journal of Naval Architecture and Ocean Engineering
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• v.9 no.3
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• pp.292-304
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• 2017

High-speed vessels are prone to the surf-riding in adverse quartering seas. The possibility of mitigating the surf-riding of the ITTC A2 fishing vessel in the design stage is investigated using the 6-DOF weakly non-linear model developed for surf-riding simulations in quartering seas. The longitudinal position of the ship's center of buoyancy (LCB) is chosen as the design parameter. The adjusting of LCB is achieved by changing frame area curves, and hull surfaces are reconstructed accordingly using the Radial Basis Function (RBF). Surf-riding motions in regular following seas for cases with different LCBs and Froude numbers are simulated using the numerical model. Results show that the surf-riding cannot be prevented by the adjusting of LCB. However, it occurs with a higher threshold speed when ship's center of buoyancy (COB) is moved towards stem compared to moving towards stern, which is mainly due to the differences on wave resistance caused by the adjusting of LCB.

• Special Issue of the Society of Naval Architects of Korea
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• 2008.09a
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• pp.106-111
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• 2008

A hull form is 181K DWT Bulk Carrier, of which new design and hull form have been developed using CFD tools and model tests. The basic concept design of hull form has been carried out with considering the factors, which are a lot of influence of the wave and viscosity resistance. The considered factors of particular are LCB, DLWL shape, tern and stem profile, Cp-curve shape, etc. Numerical calculations are carried out in the initial design stage and experimental model tests are also carried out in towing tank of MOERI. The variation of the significantly effective characteristics is carried out to achieve optimized hull form. The results from numerical calculations and model test as well as the design procedures to obtain an optimized hull form resent in this paper.

• Horticultural Science & Technology
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• v.34 no.2
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• pp.207-219
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• 2016

Incandescent (INC) lamps have been commonly used to promote flowering of long-day (LD) plants during short-day (SD) seasons, but production of INC lamps has been prohibited due to their low energy efficiency. One of the light sources replacing INC lamps is a compact fluorescent lamp (CFL). This study was carried out to compare the flowering and morphological responses of LD annuals grown in a controlled environment greenhouse at $20^{\circ}C$ with a truncated 9-h SD and a 2- or 4-h night interruption (NI) or 6-h day extension (DE) provided by lighting from INC lamps, CFLs, or a combination of the two (INC + CFLs), in which red (R) to far-red (FR) ratios were 0.60, 8.46, and 0.91, respectively, and their PPFDs were $2.3{\pm}0.3{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$. After 12 weeks of treatment, $Petunia{\times}hybrida$ 'Wave Purple' plants did not flower under the SD photoperiod whereas 100% flowered under all of the LD treatments. Flowering was more rapid under the INC or INC + CFL lighting treatments compared to CFL and DE, and 4-h NI enhanced flowering compared to 2-h NI. In addition, plants under DE and 4h-NI generally flowered earlier than under 2-h NI. All petunia 'Single Dreams Red' plants flowered within 65 days after treatment, and flowering was hastened by some LD lighting regimens and lamp types. Plants under DE and 4h-NI generally flowered earlier than under 2-h NI INC or INC + CFL compared to FL, and flowering time under INC 6-h DE was earliest. In addition, INC lighting promoted stem elongation of both petunia cultivars. In both pansy (Viola${\times}wittrockiana$) 'Coiossus Yellow' and 'Delta Blue Blotch', LD treatments, especially using INC lamps, promoted flowering whereas the lighting period had little influence on days to flowering. Therefore, INC or INC + CFL with lower R:FR promoted flowering and stem extension and the promoting effect was larger with longer lighting periods. These results suggest that CFLs can be used to provide LDs to promote the flowering of petunia and pansy and to reduce stem elongation, although the promoting effect on flowering is sometimes less than that of INC lamps alone.

• Journal of Korean Neurosurgical Society
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• v.29 no.6
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• pp.778-785
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• 2000

Objectives : Intraoperative neurophysiologic monitoring(INM) is a well known useful method to reduce intraoperative neurological complications during neurosurgical procedures. Furthermore, INM is required in most cerebellopontine angle(CPA) surgery because cranial nerves or brain stem injuries can result in serious complications. Object of this study is to the correlation between the changes of intraoperative monitoring modalities during cerebellopontine angle tumor surgery and post-operative functional outcomes in auditory and facial functions. Material and Methods : Fifty-seven patients who underwent intraoperative neurophysiologic monitoring during CPA tumor surgery were retrospectively reviewed. Their lesions were as follows ; vestibular schwannomas in 42, other cranial nerve schwannomas in seven, meningiomas in five and cysts in three cases. Pre- and postoperative audiologic examinations and facial nerve function tests were performed in all patients. Intraoperative neurophysiologic monitoring modalities includes brainstem auditory evoked potentials(BAEP) and facial electromyographies(EMG). We compared the events of INM during CPA tumor surgeries with the outcomes of auditory and facial nerve functions. Results : The subjects who had abnormal changes during CPA tumor surgery were twenty cases with BAEP changes and facial EMG changes in twenty one cases. The changes of intraoperative neurophysiologic monitoring did not always result in poor functional outcomes. However, most predictable intraoperative monitoring changes were wave III-V complex losses in BAEP and continuous neurotonic activities in facial EMG. Conclusion : These results indicate that intraoperative neurophysiologic monitoring in CPA tumor surgery usually provide predictive value for postoperative functional outcomes.

• Journal of Korean Neurosurgical Society
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• v.29 no.1
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• pp.5-14
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• 2000

Objective : Somatosensory evoked potential(SSEP) has been known to be a good method for evaluating brain stem function, but it is not sufficient to check the fine changes of cortical functions. A fine change of cortical function can be expressed with somatosensory evoked cortical field potential(SSEFP) rather than general SSEP. To confirm the usefulness of SSEFP for evaluating the cortical function, the authors simultaneously measured SSEFP and the intracranial pressure-volume index(PVI) in kaolin-induced hydrocephalic rats. Method : Hydrocephalus was induced with injection of 0.1ml kaolin-suspended solution into the cisterna magna in 60 Sprague-Dawley rats. The authors measured PVI and SSEFP 1 week after injection of kaolin-suspended solution. To evaluate the severity of induced hydrocephalus, we measured the transverse diameter of the lateral ventricle on the coronal slice of the rat brain 0.40mm posterior to the bregma. Result : The typical wave form of SSEFP in control rats showed a negative-positive complex wave at early latency. In SSEFP of normal rats, N0 is 10.0 msec, N1 15.3 msec, P1 31.2 msec and N1-P1 amplitude $15.4{\mu}V$. As hydrocephalus progressed, the peak latency of N1 and P1 were delayed. In mild hydrocephalus, negative peak waves were split. The N1-P1 amplitude was decreased only in severe hydrocephalus. The changes of the characteristics of SSEFP according to the severity of hydrocephalus were well correlated with the changes of PVI. Shunting normalized the characteristics of SSEFP in relation to ventricular sizes and PVI in hydrocephalic rats. Conclusion : SSEFP may be useful for evaluating the impairment of cortical function in hydrocephalus.

• Journal of the Korean Association of Geographic Information Studies
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• v.5 no.4
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• pp.86-92
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• 2002

The feasibility of counting number of small vessels and position in Korean waters using the panchromatic imageries derived from the IRS-1C was tested. The parameters for interpretation of satellite's imageries of small vessels were location(position), size, shape, shadow, tone, texture and pattern, height and depth, situation and association with other vessels. The position of small vessels in the sea without GCP(ground control point) was considered to be inclusive in the satellite imagery with 35 km semi-diameter, denoting rough geographical position of the vessel. The size of vessel was measured by length from stem to stern of the vessel, distinguished by following wave on the surface water. Offshore fishing vessels were separated from merchant ships by their length smaller than 100 m. The shape of vessels on panchromatic imagery of IRS-1C appeared just streamline. In case of clouds which were similar to the shape of small vessels, we were able to distinguish between vessel and cloud by shadow of cloud in the water surface. The tone of sea surface was dark black while small vessel appeared bright white. Small vessel was distinguished from the rough texture of the sea surface and the regular pattern of the waves with white capes when weather was not so good. The situation of the fishing activity was estimated by information of fishing method related to the fishing boat such as the pair trawl in the Yellow Sea.