• Applied Chemistry for Engineering
• /
• v.27 no.2
• /
• pp.205-209
• /
• 2016

The influence of titania nanorods with an average diameter of 10 nm and an average length of 30 nm on the electrohydrodynamic instability of block copolymer (polystyrene-b-poly(2-vinylpyridine)) thin film was investigated in this article. The presence of titania nanorods increased the dielectric constant of the film, which resulted in a systematic reduction in the wavelength of the surface instability. Cross-sectional transmission electron microscopy analysis indicated that the migration/aggregation of titania nanorods did not occur as a result of the applied electric field. This work can provide a simple route to the pattern formation using electrohydrodynamic instability with an aid of nanoparticles.

• FLOWER RESEARCH JOURNAL
• /
• v.16 no.3
• /
• pp.218-221
• /
• 2008

A new cultivar of Rosa hybrida 'Wooami Salmon' was developed by crossing 'Silver 87' and 'Lambada' at Gumi Floricultural Experiment Station in 2001. Characteristics trials were conducted three times from 2003 to 2006. This cultivar showed pale salmon flower color (RHS, Orange group 27-B) and standard type with good flower shape. The flower diameter is 10.8cm and the number of petals per flower is 46. Vase life of 'Wooami Salmon' could be as long as 12.8 days. The yearly mean yields of 'Wooami Salmon' was $129stems/m^2$. 'Wooami Salmon' has good quality of cut flower and strong vigor in plant growth. This cultivar is appropriate for both soil and solution(hydroponics) cultures.

• Journal of the Computational Structural Engineering Institute of Korea
• /
• v.22 no.5
• /
• pp.381-390
• /
• 2009

In this paper, a complementary analysis for the structural safety evaluation of the spent nuclear fuel disposal canister developed for the Canadian Deuterium and Uranium(CANDU) reactor for about 10,000 years long term deposition at a 500m deep granitic bedrock repository has been performed. However this developed structural model of the spent nuclear fuel disposal canister which has 33 spent nuclear fuel baskets and whose diameter is 122cm is too heavy to handle without any structural safety problem. Hence a lighter structural model of the spent nuclear fuel disposal canister which is easy to handle has been required to develop very much. There are two methods to reduce the weight of the CANDU canister model. The one is to alleviate severe design conditions such as external loads and safety factor. The other is to optimize the cross section shape of the canister by reducing the spent nuclear fuel basket number. Hence, in this paper a complementary analysis to alleviate such severe design conditions is carried out and simultaneously structural analyses to optimize the cross section shape of the canister by reducing the spent nuclear fuel basket number below 33 are carried out by varying the external load and the canister diameter for the reduction of the canister weight. The complementary analysis results show that the diameter of canister can be shortened below 122cm to reduce the weight of the spent nuclear fuel disposal canister.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.40 no.4
• /
• pp.451-459
• /
• 1995

In order to clarify the growth characteristic and Brix degree at different internodes, four varieties that are M81E 71-1, a Rio, a Sart and a Tamurama were seeded on, Apr. 5, Apr. 15, Apr. 25, May 5 and May 15, respectively. Delayed seeding increased plant hight and the growth pattern of the stem diameter and weight was tapesed off and lighted to upper location. Brix degree of internode was rapidly increased from just after heading date, and was slowly increased by rising upper side till before heading date. Brix degree of middle location(6th internode) was the highest of the stem in after heading date and interior side was the lowest. Brix percentage of 40∼45 days after heading had more than 15% in case of being seeded from Apr. 5 to May 5. Sweet sorghum that was seeded on May 15 was more than 17% in the Brix percentage of 35 days after heading and so the suitable seeding date in sourthern district was suggested on May 5. The plethora of soil moisture by rainfall was made decently lower Brix degree in 130∼140 days after seeding. Among the length and the diameter of internode, and Brix degree had negative correlation, between diameter and weight of internode were significantly positive correlation. But correlation coefficient had been a little bit different by varieties.

• Journal of Embryo Transfer
• /
• v.14 no.1
• /
• pp.17-22
• /
• 1999

To investigate the maturational and development competece of porcine oocytes of different diameter groups, oocytes were obtained by aspiration from slaughterdhouse ovaries. After washing three times in NCSU23 medium, each cumulus-oocyte complex was transferred into a $8{mu}ell$ drop of the maturation medium (one oocyte per drop) under paraffin oil. The diameter without zona pellucida of oocytes was measured with micor-calibrator (Mikrometer, E. Leitz) on a screen connected to a VCR on an inverted microscope $(200\times)$. After being measured, the oocytes were divided into 6 groups according to their diameter size : <105, 105 to < 110, 110 to < 115, 115 to < 120, 120 to < 125 and > $125{\mu}{\textrm}{m}$, and in vitro maturation (IVM), fertillzation (IVF) and production (IVP) of oocytes / embryo was performed. The rates of in vitro maturation on oocytes in the greater 105 ${\mu}{\textrm}{m}$ size groups(91.8~100%) were significantly (P<0.05) higher than in the < 105 ${\mu}{\textrm}{m}$ group(66.7%). The rates of sperm penetration were significantly (P<0.05) low in < $105{\mu}{\textrm}{m}$ group (50.0%) than others groups (81.6~85.5%). But the plyspermic fertilization rate was significantly (P<0.05) higher in < $110{\mu}{\textrm}{m}$ oocytes groups than in the $110\leq{\mu}{\textrm}{m}$ size groups. The rates of cleavage and development to blastocysts rose as oocytes diameter increased, however, while oocytes over $120{\mu}{\textrm}{m}$ in diameter failed to develop to blastocysts. There results suggest that porcine oocytes have acquired full meiotic competece at a diameter of $105{\mu}{\textrm}{m}$ but not yet attended full development competence to blastocyst and that oocytes have acquired full development competence at a diameter of $110{\mu}{\textrm}{m}$.

• Journal of the Korean Magnetics Society
• /
• v.24 no.1
• /
• pp.22-27
• /
• 2014

North indicating azimuth angle sensors have been used in airplanes, ships traditionally and nowadays employed in smart phones. For the azimuth and roll angle measurement of the sensor, 3-axis acceleration sensor was added to the 3-axis magnetic field sensor. In this work, we have constructed a measuring system for the measurement of the magnetic field and the angle uncertainty of the magnetic field sensors. Measuring system could be useful not only in non-magnetic laboratory but also in normal laboratory, we constructed small size of 3-axis Helmholtz coils for the compensation environment magnetic field (Earth magnetic field and magnetic field from building) and the generation of magnetic field for the test of magnetic field sensor. The constructed measuring system could compensate environment magnetic field below 10 nT level and generate 3-dimensional magnetic field with magnitude uncertainty of 0.2 % and angle error of $0.2^{\circ}$ within the volume of ${\pm}30mm$ diameter at center of Helmholtz coils. For the conformation of developed measuring system, We tested commercially available 3-axis magnetometer and heading sensor.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.36 no.10
• /
• pp.954-961
• /
• 2008

An experimental study has been conducted to investigate the flow field around the wing having a circular damage hole. The damage was represented by a circular hole passing through the model with 10% airfoil chord diameter and normal to the chord. The hole was centered at quarter or half chord. The PIV flow fields and static pressure measurements on the wing upper and lower surface were carried out at Rec=2.85×105 based on the chord length. The PIV results showed the two types of flow structures around a damage hole were formed. The first one was a weak jet that formed an attached wake behind the damage hole. The second one resulted from increased incidence; this was a strong jet where the flow through the hole penetrates into the free-stream resulting in extensive separation of oncoming boundary layer flow and development of a separated wake with reverse flow. The surface pressure data showed a big pressure alteration near the circular damage hole. The severity of pressure alteration was increased as a damage hole located nearer to the leading edge.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.34 no.9
• /
• pp.89-96
• /
• 2006

In this study, fluid flow and thermal characteristics in a catalyst bed for nitrous oxide catalytic decomposition which is introduced as a hybrid rocket ignition system for small satellites were theoretically considered. To analyze the thermal phenomena of the catalyst bed, a so-called porous medium approach has been opted for modeling the honeycomb geometry of the catalyst bed. Using a Brinkman-extended Darcy model for fluid flow and the one-equation model for heat transfer, the analytical solutions for both velocity and temperature distributions in the catalyst bed are obtained and compared with experimental data to validate the porous medium approach. Based on the analytical solutions, parameters of engineering importance are identified to be the porosity of the catalyst bed, effective volumetric ratio, the ratio of the radius of the catalyst bed to the radius of a pore, heat flux generated by a heater, and pumping power. Their effects on thermal phenomena of the catalyst bed are studied.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.22 no.2
• /
• pp.104-111
• /
• 1977

This study was carried out in order to know the ecological variation and yield factors under the Korea weater with the 25 sunflower varieties which have been introduced from abroad recently. As the results of this of this study we can conclude that high yield and high oil content varieties seemed to have the short period comparatively from planting to head visible and to have long period from flowering to maturity.

• Journal of Veterinary Clinics
• /
• v.29 no.4
• /
• pp.301-305
• /
• 2012

The purpose of the present study was to prove our empirical tendency of relatively high small intestinal diameter (SI) to fifth lumbar vertebral height (L5) ratio, which has been used in dogs. In this study, the ratio of SI/L5 was determined in small breed dogs weighing less than 5 kg. In addition, the effect of large volume of contrast media on the intestinal dilation was determined by performing upper gastrointestinal contrast study. Abdominal radiography and upper gastrointestinal series were performed in twelve healthy dogs weighing less than 5 kg. Small intestinal diameter (SI), fifth lumbar vertebral height (L5), and twelfth rib diameter were measured on abdominal radiographs. The range of values of SI/L5 is from 1.03 to 2.26 in plain radiography, and from 1.55 to 2.5 in contrast studies. Contrast agent significantly increased small intestinal diameter, and could be considered as mildly dilated intestinal model. Therefore, a value of 2.1 for SI/L5 is recommended as the upper limit of the normal range suggesting nonobstructive intestinal dilation.