• Magazine of the Korean Society of Agricultural Engineers
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• v.20 no.2
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• pp.4688-4694
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• 1978

The result which I tried to get double crops of potatoes on the wet paddy fields through the underdrainage of P V.C pipe from March 1977 to June 1977 in Jung cheon-Ri, Jinseong-men, Jinyang gun, Kungsangnamdo are followings.1. During this experimental period, the temperature on the average was 15.67$^{\circ}C$ (yearly mean 14.78$^{\circ}C$ that was suitable in growing potatoes, while the amount of rainfall was not much heavier from middle of April to early in May. Therefore the yield of potatoes in the wet fields was so high. 2. The soil temperature of the treated plot in the underground of 10cm, 30cm, 60cm, 80cm, has risen to 1.38$^{\circ}C$, 1.32$^{\circ}C$, 1.45$^{\circ}C$, 1.28$^{\circ}C$, comparing to the soil temperature in the control plot respectively. 3. The discharge from subdrainage pipes was 0.6751/sec/ha on the average. 4. The treated plot showed better growth than the control plot, and the yield has been increased 424.8%, while they have been preserved to be voluntary from the level of "t" test.

• Journal of the Korean Electrochemical Society
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• v.10 no.3
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• pp.179-183
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• 2007

The corrosion behavior of metal covered with mortar under a wet-dry cyclic condition were investigated to apply for the measurement of corrosion rates of reinforcing steel in concrete structure. The carbon steel in mortar having t=3 mm cover thickness was exposed to the alternate condition of 6 h immersion in chloride containing solution and 18 h drying at $25^{\circ}C$ and 50%RH. The electrochemical phenomena of a carbon steel and mortar interface was explained by an equivalent circuit consisting of a solution resistance, a charge transfer resistance and a CPE(Constant Phase Element). The corrosion rates were monitored continuously during exposure using an AC impedance technique. Simultaneously, the current distribution over the working electrode during impedance measurement was analyzed from the phase shift, $\theta$, in an intermediate frequency. The result showed that corrosion rate monitoring using an AC impedance method is suitable under the given exposure conditions even during the drying period when the metal is covered with the wetted mortar.

• Journal of Korean Society for Atmospheric Environment
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• v.20 no.4
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• pp.483-491
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• 2004

The purpose of this study is to develop an ozone passive sampler and to evaluate its performance p-Acetamidophenol using as the reagent for ozone reacts specifically with the ambient ozone to produce a fluorescence material (p-acetamidopheonl dimer). The volume of absorbent solution and the extraction time determined at suitable conditions for measuring ozone were 100$\mu$L and 60 min, respectively. The changes of fluorescence were observed with incresing the storage period of passive samplers in ambient air. but the cool storage in a refrigerator did not remarkably influence the increase of fluorescence. The measurement for the precision oi the passive sampling was carried out with duplicate measurement of passive samplers. The intra-class correlation coefficients of passive samplers using dry and wet filters were 0.992 and 0.962, respectively The results from field validation tests indicated practical agreement (dry filter: r=0.963, wet filter: r=0.995) between the passive sampler and an UV photometric $O_3$ analyzer. The limit of quantification of ozone passive samplers with sampling time of 8 hr (wet filter) and 24 hr (dry filter) were 8.0 ppb and 2.7 ppb, respectively.

• Magazine of the Korean Society of Agricultural Engineers
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• v.12 no.2
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• pp.1960-1964
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• 1970

Underdrainage has been studied by using PVC suction pipes in the low and wet Paddy field: Fist, three test plot and three control plots were set and drainage methods and Soil tempratures in the test plots have been examined. The experiment was conducted making use of the 'NONG-RIM No, 4'(Wheat) 'DOWON' (rice barley), a recommended variety. Test period was from September, to December, 1969. The experimental methodsand results obtained through this experimontation are as follows: 1) Ground water level in the test plot goes down by 34 cm. 2) In sprouting, control plot is earlier than test plot by three days. 3) The rate of sprouting is equal.

• The Journal of Korean Medicine
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• v.29 no.3
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• pp.161-168
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• 2008

We report the case of an 18-year-old woman with a 6-year history of widespread facial plane warts that had proved resistant to repeated treatments with laser therapy and imiquimod cream. The patient had recurrent lesions, which subsequently resolved with treatment. We diagnosed the case as heat and blood stasis and qi deficiency damp stagnation. Treatment with herb medication and herbal external wet dressing was initiated. During the 4-month treatment period, the warts resolved gradually. At 4 months follow up, there were no recurrent lesions and no other adverse effects.

• Journal of Environmental Science International
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• v.16 no.4
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• pp.459-466
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• 2007

To analyze the water characteristics in the dry and wet seasons, the data for temperature, salinity, nutrients and $chl-{\alpha}$ were used, which were observed in the south coastal area of Korea during April to October 2000. At Yeosu in the south coast of Korea, the higher values of 35.0 psu in salinity were shown in March and April, the lower values of 23.0 psu in salinity were shown in August and September. The annual range of salinity was 12.0 psu. The total amount of precipitation in the wet season (July to October) was occupied 68% (about 846 mm) during 2000. The precipitation of the dry season (November to June) was occupied 32% (about 394 mm) in the year In the coastal area, the salinity variation is distinct in the period of July to October. Based on this result, we divided the season into two parts: the dry season during April to June and the wet season during July to October. Factor analysis was shown that temperature has strong negative relation and nutrients show positive relations in the dry season by the factor 1, which explains the total valiance of 50.6% at the surface water. In the wet season, salinity has negative relation and nutrients show positive relation by the factor 2, which explains the total variance of 33.5%. The bottom layer also showed similar to those of surface water in the results of factor analysis. These mean that nutrients become rich due to the freshwater inflow in the wet season. The low saline water is shown not only in the south coast but also in the overall region in the South Sea of Korea. It is suggested that the South Sea of Korea may call a ROFI (Region of Freshwater Influence) system in summer.

• Journal of Ecology and Environment
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• v.44 no.3
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• pp.178-184
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• 2020

Background: Geladas (Theropithecus gelada), endemic to Ethiopia, are distributed closely related to the escarpments and gorge systems of the country, and large populations are found in the Simien Mountain National Park. This study was conducted in Eastern Tigray, Northern Ethiopia, from February 2018 to August 2019 in order to determine population size and composition of geladas. Total count method was used to estimate the population structure of geladas. Observations of the group of geladas based on body size and morphological characteristics were used to classify age and sex categories of the population. SPSS Version 20 was used to analyze the data. Chi-square test was used to compare sex ratio of geladas and population size among the counting sites between wet and dry seasons. Results: A total of 112 and 99 individual of geladas were counted during wet and dry seasons, respectively. Of the average gelada population recorded in this study, 11.4% were adult males, 30.3% were adult females, 12.8% were sub-adult males, 25.6% were sub-adult females, and 19.9% were unidentified juveniles. However, there was no statistically significant difference among the various age and sex groups of geladas counted during wet and dry season (χ² = 2.6, DF = 4, P > 0.05). Variations of group size along seasons were observed in this study. Sex ratio of adult male to adult female was 1:2.6 and 1:2.7 during the dry and wet seasons, respectively. Conclusion: Very small gelada population size was recorded in the current study. An average of 105.5 geladas was recorded during the study period. As this is the first report of gelada population in escarpments of Eastern Tigray, population trend of the geladas cannot decide based on the current study.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.37 no.2
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• pp.105-115
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• 2004

Growth pattern of the soft clam (Mya arenaria oonogei) was estimated based on samples collected from the Yeongsan River estuary on the southwest coast of Korea between August 1996 and September 1997. Mean density of the clam during study period was $55\;ind./m^2$ and varied monthly from 281 to $8\;ind./m^2.$ The clams from the study area ranged in age from one year to seven years, with shell lengths between 40.4 mm and 104.1 mm and biomass between 8.4 and 152.3 g in total wet weight. The spawing season was estimated to occur between September and October based upon a reduced fatness index, an indication of spawning, during these months. Burial depths increased with growth of the clams and most were found buried between 10 and 20 cm in the sediments. Significant relationships were found between shell length and shell height (SH), total wet weight, (TWt), meat wet weight (MWt), meat dry weight (DWt), ash free dry weight (AFDW) and burial depth. The von Bertalanffy growth equations of the clams were $L_t(mm)=138.98(1-e^{-0.1325(t+0.8853)})\;and\;W_t\;(gTWt)=325.93\;(1-e^{0.1325(t+0.8853)})^{2.6982}.$ These equations suggest that in their first year the clams should reach 31 mm in length with a biomass of 5.7 g in total wet weight.

• The Korean Journal of Malacology
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• v.14 no.2
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• pp.121-130
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• 1998

Studies on the distribution and growth of the mud mussel, Musculista senhousia, were carried out in the mud-tidal flat near Mokpo from August 1996 to July 1997. The patch distribution of the mussel was observed in the middle part of the tidalflat during the study period. Annual mean density was 8,215${\pm}$1,394 ind./m2 and annual mean biomass was 1,966.43${\pm}$668.49 g TWwt/m2 in total wet weight, 760.04${\pm}$279.13 gMWwt/m2 in meat wet weight, 209.93 ${\pm}$ 49.41 gMDwt/m2 in meat dry weight, and 109.66${\pm}$58.78 gAFDW/m2 in ash-free dry weight. The monthly mean size of shell length varied from 11.00 mm to 16.97 mm. Relationship between shell length (SL) and shell height (SH) showed a positively significant regression (SH=0.482SL+0.791, R2=0.940, P<0.001). Regressions of total wet weight (TWwt) (TWwt=7.601${\times}$10-5SL3.052, R2=0.905, P<0.001), and meat wet weight (MWwt) (MWwt=1.127${\times}$10-5${\times}$SL3.404, R2=0.784, P<0.001) on shell length were positively allometric, with highly significant correlation coefficient. The relationships between SL and meat dry weight (MDwt), and AFDW were MDwt=9.813${\times}$10-6${\times}$SL2.928 (R2=0.421), and AFDW=1.015${\times}$10-5${\times}$SL2.922(R2=0.810), respectively. The condition factor of the mussel has been increased from March and formed a peak in July and August. It was sharply dropped in September. These results suggest that the gonadal development of the species commenced to be occurred in spring and that main spawning occurred between August and September.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 1997.10a
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• pp.1.1-32
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• 1997

Atmospheric monitoring capabilities were established in 1988 by the University of Florida at Duke forest, near Durham. NC: Cary forest, near Gainesville, FL: and Austin forest, near Nacogdoches, TX. Continuous (hourly averaged) measurements of air quality (ozone, nitrogen oxides and sulfur dioxide) and meteorological variables were made at these three low elevation (< 200 meters), rural locations in the southeastern U.S. for more than three years. During the same period at these sites wet and dry acid deposition samples were collected and analyzed on an event and weekly basis, respectively The monitoring locations were selected to determine actual atmospheric exposure indices for southern pine species in support of on-site surrogate exposure chamber studies conducted by Southern Commercial Forest Research Cooperative (SCFRC) investigators. Daily and quarterly averaged ozone maxima were higher (55 ppb) at the northernmost site in the network (Duke forest) in the second and third quarters (spring and summer seasons) and lower (35 ppb) in the first and fourth quarters (winter and fall seasons), when compared to ozone levels at the two southernmost sites (Cary and Austin forests). Seasonal ozone levels at the latter two sites were similar Nitrogen oxieds and sulfur dioxide levels were insignificant (< 5 ppb) most of the time at all sites, although soil emissions of NO at two sites were found to influence nighttime ozone concentrations. Typical maximum quarterly and annual aggregate ozone exposure indices were significantly higher at Duke forest (92.5/259 ppm-hr) than those values observed at the two southern sites (65.6/210 ppm-hr). Acid deposition (wet and dry) components concentrations and deposition fluxes observed at the Duke forest, NC piedmont site, were generally greater, dependent on site and season, than corresponding variables measured at either of the two southern coastal plain sites (Cary and Austin forests). Acid deposition variables observed at the latter two sites were remarkably similar, both qualitatively and quantitatively, although the sites were located 1300 km apart. A comparison of deposition fluxes of elemental nitrogen (NO3, NH4') and sulfur (5042-, SO3) components in wet and dry forms indicated that wet deposition accounts for approximately 70% of the total nitrogen and 73% of the total sulfur input on an annual equivalent basis at all sites.