• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.3
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• pp.442-450
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• 1997

The chemical properties of water masses were investigated at 33 stations of the southeastern last Sea in February, 1995 on board R/V Tam-Yang. The water masses were not clearly distinguished due to the vortical mixing in winter. However, on the basis of the T-S and $T-O_2$ diagrams, water masses in the study area were divided into five groups (Type I, Type II, Type III, Type IV, Type V). (1) $>9.0^{\circ}C,\;>34.35\;psu,\;5.08\~5.60m\ell/\ell$ at Type I, (2) $6.0\~9.0^{\circ}C,\;34.15\~34.35\;psu,\;5.60\~5.90\;m\ell/\ell$ at Type II, (3) $4.0\~6.0^{\circ}C,\;34.00\~34.15\;psu,\;>5.90m\ell/\ell$ at Type III, (4) $1.5\~4.0^{\circ}C,\;34.00\~34.05\;psu,\;5.40\~5.90\;m\ell/\ell$ at Type IV, (5) $<1.5^{\circ}C,\;34.05\~34.07\;psu,\;4.80\~5.40\;m\ell/\ell$ at Type V. In the vertical profiles of nutrients, the concentrations were very low in the surface layer and increased rapidly with depth. The highest concentrations occurred in Type IV, while the concentrations in Type I were the lowest. The N/P ratios were less than Redfield ratio, indicating that nitrogenous nutrients were the limiting factor tor phytoplankton growth. The concentrations of POC and PON were in the range of $0.49\~20.03\;{\mu}g-at/\ell\;and\;0.09\~5.34\;{\mu}g-at/\ell$, respectively. The relatively high concentration occured in the surface layer of inner shore, showing that the concentration at each water mass followed the order Type I > Type II > Type III > Type IV > Type V, respectively. The C:N ratio in particulate organic matter was lower than the values reported in other region due to relatively high concentrations of PON in the study area. Relatively high ratios of POC to chlorophyll $\alpha$ during the study periods indicate that non-living detritus comparised most of the POC in the study area.

• Journal of Korean Society of Forest Science
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• v.35 no.1
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• pp.39-46
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• 1977

In the analysis of variance between population and between individual trees (families), the fluctuation of values of variances due to sample size, (number of family) was analysed by two different designs, i.e. 2-level nested design with equal sample size and randomized complete block design. The variables were seedling heights and root calipers of 1-0 and 1-1 seedlings of Pinus densiflora S. et Z. The details of three natural stands and their progeny characters were presented in previous reports. 1. In nested design analysis. increase of sample size resulted the decrease of F-values among families in general, however, the F-values among populations showen the increasing tendency. The smaller the sample size, the larger the F-values fluctuation was resulted in general. At the point of beyond sample size 10, however, the fluctuation become to be stabilized. The F-value fluctuation seemed to be more in the case of analysis with random sampling method than with sequentially accumulated sampling method. And also such a tendency was more obvious in smaller sample size than in large one. 2. In R.C.B.D. analysis, the sample size to affirm the family variation was smaller than that for population variations.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.11
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• pp.1653-1659
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• 2015

This study compared physicochemical properties and antioxidant activities according to different harvest times in five varieties of black rice (BR). Five cultivars of BR, Nunkeunheukchal (NKHC), Sinnongheugchal (SNHC), Sintoheugmi (STHM), Josaengheugchal (JSHC), and Heugjinju (HJJ), were selected for the study. Cultivars were transplanted on June 20th and cultivated by the Department of Southern Area Crop Science, NICS in Miryang, Korea. Heading dates of NKHC, SNHC, STHM, JSHC, and HJJ were Aug. 17th, Aug. 30th, Sep. 1st, Aug. 20th, and Aug. 12th, respectively. The five different harvest times were as follows; 35, 40, 45, 50, and 55 days after heading date. The highest level of anthocyanin was 35 days after heading date in all varieties. Levels of anthocyanin in NKHC, SNHC, STHM, JSHC, and HJJ were 164, 203, 251, 67, and 210 mg/100 g, respectively. Content of anthocyanin significantly decreased 35 days after heading in four varieties, excluding JSHC. Highest DPPH $IC_{50}$ values were 57, 29, 10, and $27{\mu}g/mL$ in NKHC, SN HC, STHM, and JSHC extracts, respectively. Highest ABTS $IC_{50}$ values were 24, 13, 9, and $11{\mu}g/mL$ in NKHC, SNHC, STHM, and JSHC extracts, respectively. The antioxidant activities were highest 35 days after the heading date and significantly decreased in four varieties, excluding HJJ. The antioxidant activity of HJJ showed no significant difference, according to harvest time. This study suggests that the content of anthocyanin and antioxidant activity could be considered as factors affecting optimal harvest period to produce highly qualified black rice.

• Journal of the East Asian Society of Dietary Life
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• v.17 no.6
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• pp.808-815
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• 2007

Four different herbs, including rosemary, oregano, basil and sage, along with green tea were individually added to ground beef at different percentages: 0.5, 1.0, and 1.5, respectively. The sensory qualities of the five natural herbs and their antioxidant effects were evaluated using Beef-Yukwonjeon. For the sensory evaluation results, the 0.5% herb addition and the control group generally showed higher acceptability scores than the 1.0% or 1.5% herb addition groups. In particular, the Yukwonjeon made with 0.5% green tea showed higher preferences in the acceptance tests and ranking tests. However, the sensory differences among samples were reduced after 3 days of storage at $6^{\circ}C$. For the results of lipid oxidation without storage, the TBARS values of the herb addition groups were slightly lower than the value of the control group, but not significantly(p>0.05). However, the antioxidant effects of each herb showed higher values over a longer storage period as well as at the higher herb concentrations. The antioxidant effects of the herbs during 7 days' of storage at $6^{\circ}C$ were evaluated as $10.0{\sim}38.5%$ reductions in TBARS values as compared to the group without herbs. Furthermore, the antioxidant effects of the herbs during 30 days' of storage at $-20^{\circ}C$ were shown as $16.8{\sim}27.8%$ reductions in the TBARS value. The green tea showed the highest antioxidant activity against lipid oxidation, because it was acceptable at higher concentrations in the sensory evaluation. These results indicate the potential to produce better quality beef-Yukwonjeon, with herbs, especially green tea.

• Journal of the Korea Concrete Institute
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• v.23 no.6
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• pp.711-722
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• 2011

Beam-column gravity or Intermediate Moment frames subjected to unexpected large displacements are vulnerable when no seismic details are provided, which is typical. Conversely, economic efficiency of those frames is decreased if unnecessary special detailing is applied as the beam and column size becomes quite large and steel congestion is caused by joint transverse reinforcement in beam-column connections. Moderate seismic design is used in Korea for beam-column connections of buildings with structural walls, which are to be destroyed when the unexpected large earthquake occurs. Nonetheless, performance of such beamcolumn connections may be substantially improved by the addition of steel fibers. This study was conducted to investigate the effect of steel fibers in reinforced concrete exterior beam-column connections and possibility for the replacement of some joint transverse reinforcement. Ten half-scale beam-column connections with non-seismic details were tested under cyclic loads with two cycles at each drift up to 19 cycles. Main test parameters used were the volume ratio of steel fibers (0%, 1%, 1.5%) and joint transverse reinforcement amount. The test results show that maximum capacity, energy dissipation capacity, shear strength and bond condition are improved with the application of steel fibers to substitute transverse reinforcement of beam-column connections. Furthermore, several shear strength equations for exterior connections were examined, including the proposed equation for steel fiber-reinforced concrete exterior connections with non-seismic details.

• Journal of Korean Society of Forest Science
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• v.32 no.1
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• pp.1-8
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• 1976

One of the most common needle leaf species used in planting in Korea is korean pine (Pinus koraiensis S. et Z.), and jack pine (Pinus banksiana Lamb.) is one of the test species for suitability. The relation of nursery bed density of 2-1 korean pine and 1-1 jack pine was studied at the Kwang Nung Nursery, Central Branch Station of Forest Research Institute, and about 40km north of Seoul. Nursery bed density of 2-1 korean pine, which ranged from 36 to 324 trees per square meters and of 1-1 jack pine, which ranged from 25 to 169 trees per square meters, had a marked effect on caliper, height, dry weight and percent and amount of plantable stock. The soil physical and chemical properties is silt plus clay, 50.55 percent; organic matter, 2.09 percent; total nitrogen, 0.13 percent; available phosphorus, 253.25 ppm; exchangeable potash, 0.46 m.e/100g; and pH, 5.58. As the density of the nursery seedling stand of 2-1 korean pine increases, the average tree height increases (Fig. 1A), but in 1-1 jack pine density do not affect to increase or decrease the average tree height. As the density of nursery bed increases, the average stem caliper (at 2cm above ground line) and dry weight decrease (Fig. 1B), but the decreasing rate is more seriously in 1-1 jack pine than 2-1 korean pine (Fig.5). As increasing the density of nursery bed, the T/R ratio of trees of the test species increase. Also the dry weight of leaf, stem and root parts are decreasing in proportion to the increase of stand density, but the drop rate of jack pine is more rapid than korean pine (table. 1) The patent facts of difference of growth characteristics between 2-1 korean pine and 1-1 jack pine were studied. These facts should be used to select the scale of stand density at the nursery bed or the plantable site. Korean pine is demanded high density, on the other hand in jack pine low density are more suitable to manage the stand density. Stands of comparatively low density had the greatest percentage of high-quality stock, and the stands of high density had less than the high quality trees of low density. An important criterion of the best density is percent and number of high-quality trees produced per square meter of bed area. Stem caliper and stem height of seedling is used in most public nurseries to sort seedling into plantable grades. The stock grade standard has set at 4.5mm caliper and 16cm height of 2-1 korean pine as the minimum desired stem caliper and height. By the result studies, the plantable stock grade standards of 2-1 korean pine used at stem height 16cm and stem caliper 4.5mm from public nurseries should be reformed to stem height 18cm and stem caliper 4.0mm by the growth characteristics and the tree distribution of stem height and caliper of relation to density. For the 2-1 korean pine, best density should be about 160 to 200 trees per square meter according to soil fertility. For the 1-1 jack pine, the suitable standard of plantable stock should be at stem height 25cm and caliper 6mm (at 2cm above ground line) and best density was about 100 to 120 trees.

• Clean Technology
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• v.20 no.1
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• pp.42-50
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• 2014

In this study, the $Mg(OH)_2$ slurry was made form ferro-nickel slag and then used for $CO_2$ sequestration. The experiments were in the order as leaching step, precipitation, carbonation experiments. According to the leaching results, the optimal leaching conditions were $H_2SO_4$ concentration of 1 M and the temperature of 333 K. In the $Mg(OH)_2$ manufacturing step, NaOH was added to increase the pH upto 8, the first precipitation was confirmed as $Fe_2O_3$. After removal the first precipitation, the pH was upto 11, the $Mg(OH)_2$ was generated by XRD analysis. The $Mg(OH)_2$ slurry was used for $CO_2$ sequestration. The pseudo-second-order carbonation model was used to apply for $CO_2$ sequestration. The $CO_2$ sequestration rate was increased by the $CO_2$ partial pressure and temperature. However, $CO_2$ sequestration rate was decreased when temperature upto 323 K. After $CO_2$ sequestrated by $Mg(OH)_2$, the $CO_2$ can be sequestrated stable as $MgCO_3$. This study also presented optimal sequestration condition was the pH upto 8.38, the maximum $MgCO_3$ can be generated. This study can be used as the basic material for $CO_2$ sequestration by ferro-nickel slag at pilot scale in the future.

• Korean journal of applied entomology
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• v.50 no.4
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• pp.373-378
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• 2011

The striped fruit fly, Bactrocera scutellata, damages pumpkin and other cucurbitaceous plants. The developmental period of each stage was measured at seven constant temperatures (15, 18, 21, 24, 27, 30, and $33{\pm}1.0^{\circ}C$). The developmental time of eggs ranged from 4.2 days at $15^{\circ}C$ to 0.9 days at $33^{\circ}C$. The developmental period of larvae was 4.2 days at $15^{\circ}C$, and slowed in temperatures above $27^{\circ}C$. The developmental period of pupa was 21.5 days at $15^{\circ}C$ and 7.6 days at $33^{\circ}C$. The mortality of eggs was 17.1% at $15^{\circ}C$ and 22.9% at $33^{\circ}C$, Larval mortalities (1st, 2nd, 3rd) were 24.1, 27.3 and 18.2%, respectively, at $15^{\circ}C$, Pupal mortalities were 18.2% at $15^{\circ}C$ and 23.1% at $33^{\circ}C$. The relationship between developmental rate and temperature fit both a linear model and a nonlinear model. The lower threshold temperatures of eggs, larvae, and pupae were 12.5, 10.7, and $6.3^{\circ}C$, respectively, and threshold temperature of the total immature period was $8.5^{\circ}C$. The thermal constants required to complete the egg, larval, and pupal stages were 33.2, 118.3, and 181.2 DD, respectively. The distribution of each development stages was described by a 3-parameter Weibull function.

• Journal of dental hygiene science
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• v.10 no.5
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• pp.307-314
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• 2010

This study aimed to measure such features of emotional responses perceived by students as learning climate, department living stress, and perceived helplessness to analyze their effects on major satisfaction among students at the department of dental hygiene; to do this, a survey was conducted with 431 students, regardless of college year, who were at the department of dental hygiene in four colleges in Gyeonggi Province, Daejeon, and Chungcheong Province. An existing emotion scale which went through the generalization process was used to draw a multiple model in the combination form in order to collect emotional factors affecting college students' satisfaction with their major, which had existed as a hypothetical proposition, and make overall interpretation of relevance through the explainable, predictable modeling process by measuring emotional factors and phenomenal description of the level of general perception. The results showed that major satisfaction was very significantly affected by emotional features among students at the department of dental hygiene, which needs to be treated as an important factor to enhance expertise related to major learning and improve students' living.

• Journal of the Korean Magnetics Society
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• v.5 no.4
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• pp.269-274
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• 1995

The basic composition of Mn-Zn ferrite was $Mn_{0.631}Zn_{0.316}Fe_{2.053}O_{4}$(specimen A), $Mn_{0.584}Zn_{0.312}Fe_{2.104}O_{4}$(specimen B) and $Mn_{0.538}Zn_{0.308}Fe_{2.154}O_{4}$(specimen C) with additional 0.1 mol % $CaCo_{3}$ and 0.04 mol % $V_{2}O_{5}$. For high per¬meability and acceleration of grain growth, $CaCo_{3}$ and $V_{2}O_{5}$. was added. The mixture of the law materials was calcinated at $950^{\circ}C$ for 3 hours and then milled. The compacts of toroidal type were sintered at different temperature($1250^{\circ}C$, $1300^{\circ}C$, $1350^{\circ}C$) for 2 hours in $N_2$ atmosphere. The effects of the various raw material composition and sintered temperature on the physical properties of Mn-Zn ferrite have been investigated. They turned out to be spinel structure by X-ray diffraction and the size of grain from SEM was from $18\;\mu\textrm{m}\;to\;23\;\mu\textrm{m}$. As the sintering temperature was increased from $1250^{\circ}C$ to $1350^{\circ}C$, the initial permeability and magnetic induction has increased and the both of Q factor and coercive force has decreased. The coercive force and curie temperature were almost the same at each specimen Their values were about 0.45 Oe and $200^{\circ}C$. The frequency of specimen will used in the range from 200 kHz to 2 MHz. The basic composition of $Mn_{0.584}Zn_{0.312}Fe_{2.104}O_{4}$(specimen B) sintered at $1300^{\circ}C$ shows the best results at magnetic induction (Br & Bm).