• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.10
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• pp.1423-1430
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• 2012

The present study investigated the relationship between physical conditions and sensory properties of red pepper powder stored at different temperatures ($-20^{\circ}C$, $0^{\circ}C$, $20^{\circ}C$) and in different wrap materials (linear low density polyethylene, LLDPE; aluminum/linear low density polyethylene, Al/LLDPE). Red pepper powders with initial moisture contents of $17.35{\pm}0.32$% were not affected by the packaging material or storage temperature. Hunter a values of red pepper powder decreased while Hunter b values increased as storage temperature increased. There were no significant differences according to packaging materials. The American Spice Trade Association (ASTA) color value ($60.85{\pm}0.13$) significantly decreased with increasing temperature from $-20^{\circ}C$ to $20^{\circ}C$ ($21.70{\pm}0.06$ to $56.03{\pm}0.24$). The ASTA color value of samples packed with LLDPE ($21.70{\pm}0.06$) decreased more compared to samples packed with other materials. Further, capsanthin contents ($13.74{\pm}0.02$ mg/100 g) significantly decreased with increasing temperature from $-20^{\circ}C$ ($0.25{\pm}0.01$ to $0.28{\pm}0.01$ mg/100 g) to $20^{\circ}C$ ($0.13{\pm}0.01$ to $0.25{\pm}0.01$ mg/100 g). In the sensory evaluation of red pepper powder, overall acceptability was influenced by redness, yellowness, and pungency color. All physicochemical and sensory properties of red pepper powder were compared. Hunter a values, ASTA color values, and capsanthin contents were significantly associated with sensory preferences. In particular, ASTA color value showed a close relationship with color preference for red pepper (R2=0.922). Thus, we suggest that the preference for red pepper powder can be determined based on instrumental measurements of Hunter a values, ASTA color values, and capsanthin contents.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.4 no.3
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• pp.226-236
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• 1999

Growth, reproduction, mortality, and production of Laminaria japonica were experimentally studied at a cultivation ground on the coast of llkwang, where the largest amount of cultivated Laminaria has been produced in Korea. For this experiment, young sporophytes (0.33 cm in mean length) grown in the laboratory were transplanted at the depth of 3 m and field surveys on them were conducted twice a month from December, 1995 to August, 1996. Plants exhibited an annual life span; they were completely dead by August. Frond width, thickness, and wet weight showed similar pattern of seasonal growth and reached their maxima in July, but frond length showed no more increment after May. Maximum mean frond length and weight were 199.8 cm and 333.0 g wet wt., respectively. Overall meristematic growth in length and weight were 384.0 cm and 393.6 g wet wt., respectively. Absolute growth rates (AGR) which were calculated from the length of tissue developed from meristem varied seasonally; AGR of length and weight reached maxima in March (3.6 $cm{\cdot}d^{-1}$) and May (3.8 g wet $wt{\cdot}d^{-1}$), respectively. Absolute attrition rates gradually increased from February to July. Seasonal differences in growth and attrition rates appeared to be related to seawater temperature and nitrogen concentration in seawater. Reproductive sporophytes bearing sprorangium sorus began to occur from April, and the ratio of sorus area to blade area reached its maximum in July (0.034). Survival rate was exponentially decreased; more than 90% of plants decayed within 56 days after outplanting. After February, mortality was size-specific; mortality of smaller plants less than 30 cm in length were relatively higher. Maximum biomass occured in July (285.6 kg wet $wt{\cdot}m^{-2}$) and annual production was 758.7 kg wet $wt{\cdot}m^{-2}$.

• Journal of Korean Society of Forest Science
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• v.83 no.3
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• pp.410-423
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• 1994

Seasonal and diurnal changes of stomatal diffusive resistance(S.D.R.) and transpiration rate(T.R.) were investigated for determining the ecophysiological water relations of economic tree species subjected to chronic water stress or exogenous abscisic acid treatment. Four species of oaks including Quercus serrata, Q. mongolica. Q. acutissima, and Q. variabilis were used as the experimental materials and also Fraxinus rhynchophylla was studied together with oaks. Stomatal diffusive resistances were repeatedly measured on the containerized 1-0 year seedlings subjected to two kinds of soil moisture regime (wet and dry) in June, August, and September by LI-1600 Steady State Porometer of LI-Cor, Inc.. Exogenous abscisic acid (ABA) solutions of 0.5 mM and 0.05 mM in July and August, respectively, were absorbed into shoots cut from the containerized seedlings for determining their effects on stomatal behavior and transpiration. Most of measurements in stomatal diffusive resistance maintained about 5 s/cm in the morning after sunrise despite of different treatments. But the values fluctuated frequently to high level above 20 s/cm through the afternoon until sunset in the seedlings subjected to dry soil moisture regime. Despite of various treatments and environmental conditions, stomatal diffusive resistances of Q. variabilis were more stable than those of Q. serrata or Q. acutissima. Their values of F. rhynchophylla changed more irregularly in comparison with those of oak species. Exogenous abscisic acid absorbed into shoots cut from seedlings increased stomatal diffusive resistance obviously in most of the species studied. The stomatal responses to abscisic acid treatment were more sensitive in July especially in Q. serrata than in Q. variabilis and Q. acutissima. But the effects of ABA treatment were presented more remarkably in Q. acutissima in August. The responses to abscisic acid were not certain in F. rhynchophylla because of their various fluctuation patterns.

• Korean Chemical Engineering Research
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• v.58 no.2
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• pp.197-208
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• 2020

This study was carried out to analyze spatial and temporal incidence characteristics of scrub typhus and predict the future incidence of scrub typhus since the incidences of scrub typhus have been rapidly increased among vector-borne diseases. A maximum entropy (MaxEnt) ecological model was implemented to predict spatial distribution and incidence rate of scrub typhus using spatial data sets on environmental and social variables. Additionally, relationships between the incidence of scrub typhus and critical spatial data were analyzed. Elevation and temperature were analyzed as dominant spatial factors which influenced the growth environment of Leptotrombidium scutellare (L. scutellare) which is the primary vector of scrub typhus. A temporal number of diseases by scrub typhus was predicted by a deep neural network (DNN). The model considered the time-lagged effect of scrub typhus. The DNN-based prediction model showed that temperature, precipitation, and humidity in summer had significant influence factors on the activity of L. scutellare and the number of diseases at fall. Moreover, the DNN-based prediction model had superior performance compared to a conventional statistical prediction model. Finally, the spatial and temporal models were used under climate change scenario. The future characteristics of scrub typhus showed that the maximum incidence rate would increase by 8%, areas of the high potential of incidence rate would increase by 9%, and disease occurrence duration would expand by 2 months. The results would contribute to the disease management and prediction for the health of residents in terms of public health.

• Journal of Korean Society of Forest Science
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• v.83 no.2
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• pp.164-174
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• 1994

Temporal changes in growth performances, chlorophyll contents, and tissue water relations for determining their physiological responses of five economic tree species subjected to chronic water and nutrition stresses were investigated with containerized seedlings grown in different soil moisture regimes and nutrition levels. Seedlings of Quercus acutissima, Q. variabilis, Q. mongolica, Q. serrata, and Fraxinus rhynchophylla were propagated in plastic pots(I.D. $16cm{\times}Depth$ 16cm) for the experiments. The seedlings were subjected to two soil moisture regimes of dry and wet soils and two nutrition levels of fertilization with N+P+K and no fertilization through the growing season from May to September in a green house. For the purpose of analyzing their responses to the environmental stresses, seedling heights and root collar diameters, chlorophyll contents, and P-V curve parameters of the seedlings were measured in May, July, and September. The environmental stresses coming from moisture and nutrient deficits affected the growth performances of seedlings variously among species and among different growing periods, as well as between height and basal diameter growth of seedlings. The growth performances of Q. acutissima were influenced sensitively on the stresses, but those of Q. mongolica less influenced in comparison with other species. Chlorophyll contents were generally higher in Quercus spp. than F. rhynchophylla through the growing season. The chlorophyll contents changed by species and by treatment through the season within ranges of 0.14~1.96 mg/g dry wt. of chlorophyll a and within 0.16~1.79mg/g dry wt. of chlorophyll b, respectively. But the contents seemed to be decreased gradually through the chronic environmental stresses and leaf senescence. The osmotic potential at full turgor(${\Psi}{{\pi}o}$) and turgor loss point(${\Psi}{\pi}p$) had temporarily declined up to 3 to 5bars from -7.0~-12.4bars in May to -10.2~-17.5bars in September and up to 5 to 6bars from -7.6~-14.2bars in May to -12.9~-20.4bars in September, respectively, with some exceptions. The values of ${\Psi}{\pi}p$ were generally high in F. rhynchophylla in May and July, but high in Q. serrata in September. Relative water contents at turgor loss point(RWCp) were generally high in F. rhynchophylla, but the temporal changes of RWCp were quite and frequently different among species and among treatment.

• Journal of Conservation Science
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• v.29 no.3
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• pp.287-296
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• 2013

Excavated iron objects are preserved in stable condition through processes of conservation treatment because they are found in the form of various corrosion products. However, the conservation treatment leads to re-corrosion over time and accordingly, iron objects can be severely damaged, and therefore fundamental measures need to be prepared to control it. In this study, the types and characteristics of corrosion products were scientifically analyzed according to the re-corrosion of iron artifacts. In addition, the stability of the corrosion products was evaluated by exposing the standard samples under the re-corrosion environment. Re-corrosion proceeded with weeping in reddish brown on the cracks of iron artifacts. Weeping was detected akagan$\acute{e}$ite had a low hydrogen ion concentration and high chloride ion. The selection of standard sample goethite, lepidocrocite, hematite, and magnetite, were evaluated corrosive by weeping. After the samples were immersed in HCl(pH 1), $H_2SO_4$(pH 1), $H_2O$(pH 6) solution, they had been maintained for 180 days in relative humidity of 20%, 50%, 80% to investiage the changes of chemical components. As a result of analysis, the changes of chemical components were not showed in goethite, lepidocrocite, and hematite. But magnetite was changed to lepidocrocite in solution including chloride ion($Cl^-$) and to goethite and lepidocrocite solution including sulfuric acid($SO{_4}^{2-}$). Results of the study, in the case of magnetite known as s stable corrosion compound, it was identified the corrosion of magnetite occurs by corrosive ions, which means weeping generated in the iron artifacts can corrode magnetite as well as base metal.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.46 no.6
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• pp.453-458
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• 2001

The Rural Development Administration (RDA) of Korea now operates a system called Rice Variety Selection Tests (RVST), which are now being implemented in eight Agricultural Research and Extension Services located in eight province RVST's objective is to provide accurate yield estimates and to select well-adapted varieties to each province. Systematic evaluation of entries included in RVST is a highly important task to select the best-adapted varieties to specific location and to observe the performance of entries across a wide range of test sites within a region. The rice yield data in RVST for ordinary transplanting in Kangwon province during 1997-2000 were analyzed. The experiments were carried out in three replications of a random complete block design with eleven entries across five locations. Additive Main effects and Multiplicative Interaction (AMMI) model was employed to examine the interaction between genotype and environment (G$\times$E) in the biplot form. It was found that genotype variability was as high as 66％, followed by G$\times$E interaction variability, 21％, and variability by environment, 13％. G$\times$E interaction was partitioned into two significant (P＜0.05) principal components. Pattern analysis was used for interpretation on G$\times$E interaction and adaptibility. Major determinants among the meteorological factors on G$\times$E matrix were canopy minimum temperature, minimum relative humidity, sunshine hours, precipitation and mean cloud amount. Odaebyeo, Obongbyeo and Jinbubyeo were relatively stable varieties in all the regions. Furthermore, the most adapted varieties in each region, in terms of productivity, were evaluated.

• Journal of the Korean Wood Science and Technology
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• v.2 no.2
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• pp.8-12
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• 1974

1. If one unity is given to the prongs whose ends touch each other for estimating the internal stresses occuring in it, the internal stresses which are developed in the open prongs can be evaluated by the ratio to the unity. In accordance with the above statement, an equation was derived as follows. For employing this equation, the prongs should be made as shown in Fig. I, and be measured A and B' as indicated in Fig. l. A more precise value will result as the angle (J becomes smaller. $CH=\frac{(A-B') (4W+A) (4W-A)}{2A[(2W+(A-B')][2W-(A-B')]}{\times}100%$ where A is thickness of the prong, B' is the distance between the two prongs shown in Fig. 1 and CH is the value of internal stress expressed by percentage. It precision is not required, the equation can be simplified as follows. $CH=\frac{A-B'}{A}{\times}200%$ 2. Under scheduled drying condition III the kiln, when the weight of a sample board is constant, the moisture content of the shell of a sample board in the case of a normal casehardening is lower than that of the equilibrium moisture content which is indicated by the Forest Products Laboratory, U. S. Department of Agriculture. This result is usually true, especially in a thin sample board. A thick unseasoned or reverse casehardened sample does not follow in the above statement. 3. The results in the comparison of drying rate with five different kinds of wood given in Table 1 show that the these drying rates, i.e., the quantity of water evaporated from the surface area of I centimeter square per hour, are graded by the order of their magnitude as follows. (1) Ginkgo biloba Linne (2) Diospyros Kaki Thumberg. (3) Pinus densiflora Sieb. et Zucc. (4) Larix kaempheri Sargent (5) Castanea crenata Sieb. et Zucc. It is shown, for example, that at the moisture content of 20 percent the highest value revealed by the Ginkgo biloba is in the order of 3.8 times as great as that for Castanea crenata Sieb. & Zucc. which has the lowest value. Especially below the moisture content of 26 percent, the drying rate, i.e., the function of moisture content in percentage, is represented by the linear equation. All of these linear equations are highly significant in testing the confficient of X i. e., moisture content in percentage. In the Table 2, the symbols are expressed as follows; Y is the quantity of water evaporated from the surface area of 1 centimeter square per hour, and X is the moisture content of the percentage. The drying rate is plotted against the moisture content of the percentage as in Fig. 2. 4. One hundred times the ratio(P%) of the number of samples occuring in the CH 4 class (from 76 to 100% of CH ratio) within the total number of saplmes tested to those of the total which underlie the given SR ratio is measured in Table 3. (The 9% indicated above is assumed as the danger probability in percentage). In summarizing above results, the conclusion is in Table 4. NOTE: In Table 4, the column numbers such as 1. 2 and 3 imply as follows, respectively. 1) The minimum SR ratio which does not reveal the CH 4, class is indicated as in the column 1. 2) The extent of SR ratio which is confined in the safety allowance of 30 percent is shown in the column 2. 3) The lowest limitation of SR ratio which gives the most danger probability of 100 percent is shown in column 3. In analyzing above results, it is clear that chestnut and larch easly form internal stress in comparison with persimmon and pine. However, in considering the fact that the revers, casehardening occured in fir and ginkgo, under the same drying condition with the others, it is deduced that fir and ginkgo form normal casehardening with difficulty in comparison with the other species tested. 5. All kinds of drying defects except casehardening are developed when the internal stresses are in excess of the ultimate strength of material in the case of long-lime loading. Under the drying condition at temperature of $170^{\circ}F$ and the lower humidity. the drying defects are not so severe. However, under the same conditions at $200^{\circ}F$, the lower humidity and not end coated, all sample boards develop severe drying defects. Especially the chestnut was very prone to form the drying defects such as casehardening and splitting.

• Journal of the Korean Institute of Landscape Architecture
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• v.48 no.5
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• pp.80-88
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• 2020

With the issuance of one-week fine dust emergency reduction measures in March 2019, the public's anxiety about fine dust is increasingly growing. In order to assess the application of air purifying plant-based bio-filters to public facilities, this study presented a method for measuring pollutant reduction effects by creating an indoor environment for continuous discharge of particle pollutants and conducted basic studies to verify whether indoor air quality has improved through the system. In this study conducted in a lecture room in spring, the background concentration was created by using mosquito repellent incense as a pollutant one hour before monitoring. Then, according to the schedule, the fine dust reduction capacity was monitored by irrigating for two hours and venting air for one hour. PM₁₀, PM_2.5, and temperature & humidity sensors were installed two meters front of the bio-filters, and velocity probes were installed at the center of the three air vents to conduct time-series monitoring. The average face velocity of three air vents set up in the bio-filter was 0.38±0.16 m/s. Total air-conditioning air volume was calculated at 776.89±320.16㎥/h by applying an air vent area of 0.29m×0.65m after deducing damper area. With the system in operation, average temperature and average relative humidity were maintained at 21.5-22.3℃, and 63.79-73.6%, respectively, which indicates that it satisfies temperature and humidity range of various conditions of preceding studies. When the effects of raising relatively humidity rapidly by operating system's air-conditioning function are used efficiently, it would be possible to reduce indoor fine dust and maintain appropriate relative humidity seasonally. Concentration of fine dust increased the same in all cycles before operating the bio-filter system. After operating the system, in cycle 1 blast section (C-1, β=-3.83, β=-2.45), particulate matters (PM₁₀) were lowered by up to 28.8% or 560.3㎍/㎥ and fine particulate matters (PM_2.5) were reduced by up to 28.0% or 350.0㎍/㎥. Then, the concentration of find dust (PM₁₀, PM_2.5) was reduced by up to 32.6% or 647.0㎍/㎥ and 32.4% or 401.3㎍/㎥ respectively through reduction in cycle 2 blast section (C-2, β=-5.50, β=-3.30) and up to 30.8% or 732.7㎍/㎥ and 31.0% or 459.3㎍/㎥ respectively through reduction in cycle 3 blast section (C-3, β=5.48, β=-3.51). By referring to standards and regulations related to the installation of vegetation bio-filters in public facilities, this study provided plans on how to set up objective performance evaluation environment. By doing so, it was possible to create monitoring infrastructure more objective than a regular lecture room environment and secure relatively reliable data.

• Korean Journal of Environmental Agriculture
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• v.35 no.3
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• pp.175-183
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• 2016

BACKGROUND: There's a long rainy season during the Summer in Northeast Asia, including Korea. Heavy rainfall during this season causes harm to tree's root, and damped injury in the pear has been continuously reported. Pear Research Institute is breeding damp resistant rootstocks and investigating their mechanisms to relieve damped damages in the pear.METHODS AND RESULTS: Seedlings of Pyrus betulaefolia and P. calleryana were divided into two groups: control and damped, respectively. Damped group was treated by constant irrigation for 77 days and control group was maintained to keep the soil moisture pressure between 0 and -10 kPa. After the treatment, we analysed trees' growth rate, chlorophyll content, amino acids and total phenolic compounds. As a result, P. betulaefolia was sensitive to damped treatment while P. calleryana did not have significant differences between the control and damped treatment. It was observed that total contents for phenolic compounds were dramatically increased in P. betulaefolia while trees' growth rate, chlorophyll b and general amino acid contents were lowered by damping treatment.CONCLUSION: In some pear cultivars, growth habit is suppressed by damped damage. Pyrus calleryana displayed tolerances to damped damage in growth rate and some organic compound contents compared to P. betulaefolia. So we recommend to exploit P. calleryana as a pear rootstock rather than using P. betulaefolia.