• Journal of Korean Society of Environmental Engineers
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• v.30 no.6
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• pp.642-652
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• 2008

The aim of our research was to apply experimental design methodology in the optimization condition of Photo-Fenton oxidation of the residual livestock wastewater after the coagulation process. The reactions of Photo-Fenton oxidation were mathematically described as a function of parameters amount of Fe(II)($x_1$), $H_2O_2(x_2)$ and pH($x_3$) being modeled by the use of the Box-Behnken method, which was used for fitting 2nd order response surface models and was alternative to central composite designs. The application of RSM using the Box-Behnken method yielded the following regression equation, which is an empirical relationship between the removal(%) of livestock wastewater and test variables in coded unit: Y = 79.3 + 15.61x$_1$ - 7.31x$_2$ - 4.26x$_3$ - 18x$_1{^2}$ - 10x$_2{^2}$ - 11.9x$_3{^2}$ + 2.49x$_1$x$_2$ - 4.4x$_2$x$_3$ - 1.65x$_1$x$_3$. The model predicted also agreed with the experimentally observed result(R$^2$ = 0.96) The results show that the response of treatment removal(%) in Photo-Fenton oxidation of livestock wastewater were significantly affected by the synergistic effect of linear terms(Fe(II)($x_1$), $H_2O_2(x_2)$, pH(x$_3$)), whereas Fe(II) $\times$ Fe(II)(x$_1{^2}$), $H_2O_2$ $\times$ $H_2O_2$(x$_2{^2}$) and pH $\times$ pH(x$_3{^2}$) on the quadratic terms were significantly affected by the antagonistic effect. $H_2O_2$ $\times$ pH(x$_2$x$_3$) had also a antagonistic effect in the cross-product term. The estimated ridge of the expected maximum response and optimal conditions for Y using canonical analysis were 84 $\pm$ 0.95% and (Fe(II)(X$_1$) = 0.0146 mM, $H_2O_2$(X$_2$) = 0.0867 mM and pH(X$_3$) = 4.704, respectively. The optimal ratio of Fe/H$_2O_2$ was also 0.17 at the pH 4.7.

• Magazine of the Korean Society of Agricultural Engineers
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• v.13 no.1
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• pp.2206-2217
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• 1971

Spillway and discharge channel of reservoirs require the Control of Large volume of water under high pressure. The energies at the downstream end of spillway or discharge channel are tremendous. Therefore, Some means of expending the energy of the high-velocity flow is required to prevent scour of the riverbed, minimize erosion, and prevent undermining structures or dam it self. This may be accomplished by Constructing an energy dissipator at the downstream end of spillway or discharge channel disigned to dissipated the excessive energy and establish safe flow Condition in the outlet channel. There are many types of energy dissipators, stilling basins are the most familar energy dissipator. In the stilling basin, most energies are dissipated by hydraulic jump. stilling basins have some length to cover hydraulic jump length. So stilling basins require much concrete works and high construction cost. Flip bucket type energy dissipators require less construction cost. If the streambed is composed of firm rock and it is certain that the scour will not progress upstream to the extent that the safety of the structure might be endangered, flip backet type energy dissipators are the most recommendable one. Following items are tested and studied with bucket radius, $R=7h_2$,(medium of $4h_2{\geqq}R{\geqq}10h_2$). 1. Allowable upstream channel slop of bucket. 2. Adequate bucket lip angle for good performance of flip bucket. Also followings are reviwed. 1. Scour by jet flow. 2. Negative pressure distribution and air movement below nappe flow. From the test and study, following results were obtained. 1. Upstream channel slope of bucket (S=H/L) should be 0.25<H/L<0.75 for good performance of flip bucket. 2. Adequated lip angle $30^{\circ}{\sim}40^{\circ}$ are more reliable than $20^{\circ}{\sim}30^{\circ}$ for the safety of structures.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.32 no.1
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• pp.107-119
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• 2014

The purpose of this study is to examine the current status of vascular plants and naturalized plants growing in the Seongeup Folk Village in Jeju and to consider and compare their distribution patterns and the characteristics of emergence of naturalized plants in other folk villages and all parts of Jeju, thereby exploring measures to well manage naturalized plants. The result of this study is as follows.11) The total number of vascular plants growing in Seongeup Folk Village is identified to be 354 taxa which include 93 families, 260 genus, 298 species, 44 varieties and 12 breeds. Among them, the number of naturalized plants is 55 taxa in total including 22 families, 46 genus, 53 species, and 2 varieties, which accounts for 21.7% of the total of 254 taxa identified all over the region of Jeju. The rate of naturalization in Seongeup Folk Village is 15.5%, which is far higher than the rates of plant naturalization in Hahoi Village in Andong, Yangdong Village in Gyeongju, Hangae Village in Seongju, Wanggok Village in Goseong, and Oeam Village in Asan. Among the naturalized plants identified within the targeted villages, the number of those growing in Jeju is 9 taxa including Silene gallica, Modiola caroliniana, Oenothera laciniata, Oenothera stricta, Apium leptophyllum, Gnaphalium purpureum, Gnaphalium calviceps, Paspalum dilatatum and Sisyrinchium angustifolium. It is suggested that appropriate management measures that consider the characteristics of the gateway to import and the birthplace of the naturalized plants are necessary. In the meantime, 3 more taxa that have not been included in the reference list of Jeju have been identified for the first time in Seongeup Folk Village, which include Bromus sterilis, Cannabis sativa and Veronica hederaefolia. The number of naturalized plants identified within the gardens of unit-based cultural properties is 20 taxa, among which the rate of prevalence of Cerastium glomeratum is the highest at 62.5%. On the other hand, the communities of plants that require landscape management are Brassica napus and other naturalized plants, including Cosmos bipinnatus, Trifolium repens, Medicago lupulina, Oenothera stricta, O. laciniata, Lotus corniculatus, Lolium perenne, Silene gallica, Hypochaeris radicata, Plantago virginica, Bromus catharticus and Cerastium glomeratum. As a short-term measure to manage naturalized plants growing in Seongeup Folk Village, it is important to identify the current status of Cosmos bipinnatus and Brassica napus that have been planted for landscape agriculture, and explore how to use flowers during the blooming season. It is suggested that Ambrosia artemisiifolia and Hypochaeris radicata, designated as invasive alien plants by the Ministry of Health and Welfare, should be eradicated initially, followed by regular monitoring in case of further invasion, spread or expansion. As for Hypochaeris radicata, in particular, some physical prevention measures need to be explored, such as for example, identifying the habitat density and eradication of the plant. In addition, it is urgent to remove plants, such as Sonchus oleraceus, Houttuynia cordata, Crassocephalum crepidioides, Erigeron annuus and Lamium purpureum with high index of greenness visually, growing wild at around high Jeongyi town walls. At the same time, as the distribution and dominance value of the naturalized plants growing in deserted or empty houses are high, it is necessary to find measures to preserve and manage them and to use the houses as lodging places.

• Journal of Korean Society of Environmental Engineers
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• v.32 no.1
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• pp.33-46
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• 2010

We investigated and estimated at the characteristics of decomposition and by-products of N-Nitrosodimethylamine (NDMA) using a design of experiment (DOE) based on the Box-Behken design in an UV process, and also the main factors (variables) with UV intensity($X_2$) (range: $1.5{\sim}4.5\;mW/cm^2$), NDMA concentration ($X_2$) (range: 100~300 uM) and pH ($X_2$) (rang: 3~9) which consisted of 3 levels in each factor and 4 responses ($Y_1$ (% of NDMA removal), $Y_2$ (dimethylamine (DMA) reformation (uM)), $Y_3$ (dimethylformamide (DMF) reformation (uM), $Y_4$ ($NO_2$-N reformation (uM)) were set up to estimate the prediction model and the optimization conditions. The results of prediction model and optimization point using the canonical analysis in order to obtain the optimal operation conditions were $Y_1$ [% of NDMA removal] = $117+21X_1-0.3X_2-17.2X_3+{2.43X_1}^2+{0.001X_2}^2+{3.2X_3}^2-0.08X_1X_2-1.6X_1X_3-0.05X_2X_3$ ($R^2$= 96%, Adjusted $R^2$ = 88%) and 99.3% ($X_1:\;4.5\;mW/cm^2$, $X_2:\;190\;uM$, $X_3:\;3.2$), $Y_2$ [DMA conc] = $-101+18.5X_1+0.4X_2+21X_3-{3.3X_1}^2-{0.01X_2}^2-{1.5X_3}^2-0.01X_1X_2+0.07X_1X_3-0.01X_2X_3$ ($R^2$= 99.4%, 수정 $R^2$ = 95.7%) and 35.2 uM ($X_1$: 3 $mW/cm^2$, $X_2$: 220 uM, $X_3$: 6.3), $Y_3$ [DMF conc] = $-6.2+0.2X_1+0.02X_2+2X_3-0.26X_1^2-0.01X_2^2-0.2X_3^2-0.004X_1X_2+0.1X_1X_3-0.02X_2X_3$ ($R^2$= 98%, Adjusted $R^2$ = 94.4%) and 3.7 uM ($X_1:\;4.5\;$mW/cm^2$, $X_2:\;290\;uM$, $X_3:\;6.2$) and $Y_4$ [$NO_2$-N conc] = $-25+12.2X_1+0.15X_2+7.8X_3+{1.1X_1}^2+{0.001X_2}^2-{0.34X_3}^2+0.01X_1X_2+0.08X_1X_3-3.4X_2X_3$ ($R^2$= 98.5%, Adjusted $R^2$ = 95.7%) and 74.5 uM ($X_1:\;4.5\;mW/cm^2$, $X_2:\;220\;uM$, $X_3:\;3.1$). This study has demonstrated that the response surface methodology and the Box-Behnken statistical experiment design can provide statistically reliable results for decomposition and by-products of NDMA by the UV photolysis and also for determination of optimum conditions. Predictions obtained from the response functions were in good agreement with the experimental results indicating the reliability of the methodology used.

• Journal of environmental and Sanitary engineering
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• v.24 no.4
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• pp.1-26
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• 2009

We conclude the following with air pollution data measured from city measurement net administered and managed in Gwangju for the last 7 years from January in 2001 to December in 2007. In addition, some major statistics governed by Gwangju city and data administered by Gwangju as national official statistics obtained by estimating the amount of national air pollutant emission from National Institute of Environmental Research were used. The results are as follows ; 1. The distribution by main managements of air emission factory is the following ; Gwangju City Hall(67.8%) > Gwangsan District Office(13.6%) > Buk District Office(9.8%) > Seo District Office(5.5%) > Nam District Office(3.0%) > Dong District Office(0.3%) and the distribution by districts of air emission factory ; Buk District(32.8%) > Gwangsan District(22.4%) > Seo District(21.8%) > Nam District(14.9%) > Dong District(8.1%). That by types(Year 2004~2007 average) is also following ; Type 5(45.2%) > Type 4(40.7%) > Type 3(8.6%) > Type 2(3.2%) > Type 1(2.2%) and the most of them are small size of factory, Type 4 and 5. 2. The distribution by districts of the number of car registrations is the following ; Buk District(32.8%) > Gwangsan District(22.4%) > Seo District(21.8%) > Nam District(14.9%) > Dong District(8.1%) and the distribution by use of car fuel in 2001 ; Gasoline(56.3%) > Diesel(30.3%) > LPG(13.4%) > etc.(0.2%). In 2007, there was no ranking change ; Gasoline(47.8%) > Diesel(35.6%) > LPG(16.2%) >etc.(0.4%). The number of gasoline cars increased slightly, but that of diesel and LPG cars increased remarkably. 3. The distribution by items of the amount of air pollutant emission in Gwangju is the following; CO(36.7%) > NOx(32.7%) > VOC(26.7%) > SOx(2.3%) > PM-10(1.5%). The amount of CO and NOx, which are generally generated from cars, is very large percentage among them. 4. The distribution by mean of air pollutant emission(SOx, NOx, CO, VOC, PM-10) of each county for 5 years(2001~2005) is the following ; Buk District(31.0%) > Gwangsan District(28.2%) > Seo District(20.4%) > Nam District(12.5%) > Dong District(7.9%). The amount of air pollutant emission in Buk District, which has the most population, car registrations, and air pollutant emission businesses, was the highest. On the other hand, that of air pollutant emission in Dong District, which has the least population, car registrations, and air pollutant emission businesses, was the least. 5. The average rates of SOx for 5 years(2001~2005) in Gwangju is the following ; Non industrial combustion(59.5%) > Combustion in manufacturing industry(20.4%) > Road transportation(11.4%) > Non-road transportation(3.8%) > Waste disposal(3.7%) > Production process(1.1%). And the distribution of average amount of SOx emission of each county is shown as Gwangsan District(33.3%) > Buk District(28.0%) > Seo District(19.3%) > Nam District(10.2%) > Dong District(9.1%). 6. The distribution of the amount of NOx emission in Gwangju is shown as Road transportation(59.1%) > Non-road transportation(18.9%) > Non industrial combustion(13.3%) > Combustion in manufacturing industry(6.9%) > Waste disposal(1.6%) > Production process(0.1%). And the distribution of the amount of NOx emission from each county is the following ; Buk District(30.7%) > Gwangsan District(28.8%) > Seo District(20.5%) > Nam District(12.2%) > Dong District(7.8%). 7. The distribution of the amount of carbon monoxide emission in Gwangju is shown as Road transportation(82.0%) > Non industrial combustion(10.6%) > Non-road transportation(5.4%) > Combustion in manufacturing industry(1.7%) > Waste disposal(0.3%). And the distribution of the amount of carbon monoxide emission from each county is the following ; Buk District(33.0%) > Seo District(22.3%) > Gwangsan District(21.3%) > Nam District(14.3%) > Dong District(9.1%). 8. The distribution of the amount of Volatile Organic Compound emission in Gwangju is shown as Solvent utilization(69.5%) > Road transportation(19.8%) > Energy storage & transport(4.4%) > Non-road transportation(2.8%) > Waste disposal(2.4%) > Non industrial combustion(0.5%) > Production process(0.4%) > Combustion in manufacturing industry(0.3%). And the distribution of the amount of Volatile Organic Compound emission from each county is the following ; Gwangsan District(36.8%) > Buk District(28.7%) > Seo District(17.8%) > Nam District(10.4%) > Dong District(6.3%). 9. The distribution of the amount of minute dust emission in Gwangju is shown as Road transportation(76.7%) > Non-road transportation(16.3%) > Non industrial combustion(6.1%) > Combustion in manufacturing industry(0.7%) > Waste disposal(0.2%) > Production process(0.1%). And the distribution of the amount of minute dust emission from each county is the following ; Buk District(32.8%) > Gwangsan District(26.0%) > Seo District(19.5%) > Nam District(13.2%) > Dong District(8.5%). 10. According to the major source of emission of each items, that of oxides of sulfur is Non industrial combustion, heating of residence, business and agriculture and stockbreeding. And that of NOx, carbon monoxide, minute dust is Road transportation, emission of cars and two-wheeled vehicles. Also, that of VOC is Solvent utilization emission facilities due to Solvent utilization. 11. The concentration of sulfurous acid gas has been 0.004ppm since 2001 and there has not been no concentration change year by year. It is considered that the use of sulfurous acid gas is now reaching to the stabilization stage. This is found by the facts that the use of fuel is steadily changing from solid or liquid fuel to low sulfur liquid fuel containing very little amount of sulfur element or gas, so that nearly no change in concentration has been shown regularly. 12. Concerning changes of the concentration of throughout time, the concentration of NO has been shown relatively higher than that of $NO_2$ between 6AM~1PM and the concentration of $NO_2$ higher during the other time. The concentration of NOx(NO, $NO_2$) has been relatively high during weekday evenings. This result shows that there is correlation between the concentration of NOx and car traffics as we can see the Road transportation which accounts for 59.1% among the amount of NOx emission. 13. 49.1~61.2% of PM-10 shows PM-2.5 concerning the relationship between PM-10 and PM-2.5 and PM-2.5 among dust accounts for 45.4%~44.5% of PM-10 during March and April which is the lowest rates. This proves that particles of yellow sand that are bigger than the size $2.5\;{\mu}m$ are sent more than those that are smaller from China. This result shows that particles smaller than $2.5\;{\mu}m$ among dust exist much during July~August and December~January and 76.7% of minute dust is proved to be road transportation in Gwangju.

• Korean Journal of Soil Science and Fertilizer
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• v.12 no.3
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• pp.117-124
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• 1979

The present work was carried out to study the fate of applied phosphorus labelled with $^{32}P$ and its availability to plants in soils subjected to different management practices. The results can be summarized as follows (Table 3): 1. The applied phosphorus was transformed into different phosphorus compounds in the soils depending upon the management practices and soil characteristics. 2. In the flooded paddy soil (pH 5.8) added P after one week of incubation was transformed into various fractions, the order of abundance being: Al-P> Ca-P$${\sim_\sim}$$Fe-P> Org.-P. After two weeks the order changed to: Fe-P> Al-P> Ca-P> Org.-P. The amounts of the Fe-P and Al-P fractions were found to increase from the second week of incubation whereas a decrease in Ca-P was noticed with the organic-P remaining constant. The amount of available P decreased from the first to the third week of incubation, but increased thereafter. 3. In the volcanic ash soil a major proportion of the applied phosphorus was found in the Fe-P fraction during the whole experimental period. The interconversions of the $^{32}P$ among the different phosphate fractions was not as evident as in the case of flooded rice soil. The recovery of applied P was low and remained constant throughout the incubation period. 4. In the upland soils relatively more of the applied phosphorus was found in the Ca-P fraction as compared with those of the other soils. As in the flooded paddy soil $^{32}P$ in the Ca-P fraction decreased with increasing incubation time, whereas in the Fe-P fraction it increased with time. The recovery of added phosphate as available P followed different patterns for the cultivated and the uncultivated soils. In the cultivated soils lit was relatively high and remained nearly constant during the whole incubation period. In the uncultivated soil on the other hand, it was high at the earlier time of incubation, but decreased with incubation time.

• Radiation Oncology Journal
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• v.18 no.3
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• pp.194-199
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• 2000

Purpose : Then determining the lower margin of post-operative pelvic radiation therapy field according to the traditional method (recommended by Gunderson), the organs located in the low pelvic cavity and the perineum are vulnerable to unnecessary radiation. This study evaluated the effect of individualized determination of the lower margin at 2 cm to 3 cm below the anastomotic site on the failure patterns. Materials and Methods . Authors included ぉ patients with modified Astler-Coiler (MAC) stages from B2 through C3, who received low anterior resection and post-operative pelvic radiation therapy from Sept. 1994 to May 1998 at Samsung Medical Center, Sungkyunkwan University. The numbers of male and female patients were 44 and 44, and the median age was 57 years (range: 32-81 years). Three field technique (posterior-anterior and bilateral portals) by 6, 10, 15 MV X-rays was used to deliver 4,500 cGy to the whole pelvis followed by Sn cGy's small field boost to the tumor bed over 5.5 weeks. Sixteen patients received radiation therapy by traditional field margin determination, and the lower margin was set either at the low margin of the obturator foramen or at 2 cm to 3 cm below the anastomotic site, whichever is lower. In 72 patients, the lower margin was set at 2 cm to 3 cm below the anastomotic site, irrespectively of the obturator foramen, by which the reduction of radiation volume was possible in 55 patients ($76\%$). Authors evaluated and compared survival, local control, and disease-free survival rates of these two groups. Results : The median follow-up period was 27 months (range : 7-58 months). MAC stages B2 in 32($36\%$), B3 in 2 ($2\%$), Cl in 2 ($2\%$), C2 in 50 ($57\%$), and C3 in 2 ($2\%$) Patients, respectively. The entire patients' overall survival rates at 2 and 4 years were $94\%$ and $68\%$, respectively, and disease-free survival rates at 2 and 4 years were $86\%$ and $58\%$, respectively. The first failure sites were local only in 4, distant only in 14, and combined local and distant in 1 patient, respectively. There was no significant difference with respect to local control and disease-free survival rates ( p=0.42, p=0.68) between two groups of different lower margin determination policies. Conclusion : The new concept in the individualized determination of the lower margin depending on the anastomotic site has led to the equivalent local control and disease-free survival rates, and is expected to contribute to the reduction of unnecessary radiation-related morbidity by reduction of radiation volume, compared with the traditional method of lower margin determination.

• Korean Journal of Agricultural Science
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• v.5 no.2
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• pp.149-157
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• 1978

This study was carried out to obtain basic data for the type selection of furrow openers for the no-tillage soybean planter trailed by the two-wheel tractor from the standpoint of minimum draft and good performance of furrowing. For this study, two models of furrow opener, hoe and disc type, were tested on the artificial soil stuffed in the moving soil bin. The results obtained were as follows. In the case of disc furrow opener, the drafts were measured according to various diameters of discs under the condition of disc angle $8^{\circ}$ and $16^{\circ}$, working depth 3cm and 6cm, working speed 2.75cm/sec. Minimum draft appeared when the diameter of disc was about 28cm and the drafts increased as the diameter of discs became larger or smaller than this diameter. Specific draft showed almost same tendencies as above but showed the minimum when the diameter was about 30cm. For the purpose of controlling the seeding depth, the relationships between draft and working depths, 3cm and 6cm, were tested. The variations of draft concerning the various working depths showed linear changes and were affected in higher degree by depths than other factors. There were general tendencies at both working depths, 3cm and 6cm, that total draft showed the minimum with the disc diameter of about 28cm and specific draft showed it with the disc diameter of about 30cm regardless of disc angle and working speed. For the purpose of controlling the working width and speed, the relationships among drafts, disc angle and working speed were investigated and there were general tendencies that the draft increased as the angle and speed were increased and the draft was affected more by speed than by angle. To compare the hoe-type with disc-type opener, the specific drafts of hoe openers were compared with those of disc opener of $16^{\circ}$ angle and 30cm diameter. The specific draft of disc-type opener with the diameter of 30cm was $0.35{\sim}0.5kg/cm^2$, while $0.71{\sim}1.02kg/cm^2$ in the case of hoe type with the lift angle of $20^{\circ}$ which is 2 times as much as that of disc type in average value. And the furrows opened by disc openers were cleaner than those opened by hoe openers.

• Korean Journal of Agricultural Science
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• v.4 no.2
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• pp.317-343
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• 1977

This study was carried out to obtain the informations about evaporation from pot, soil temperature and soil atmosphere composition in pot, and the effect on the growth of nine ornamental species using seven different containers. The investigated containers were clay pot(CP), clay pot painted in green(CP-P), varnished clay pot(CP-V), polyethylene film inserting in clay pot(CP-PI), clay pot mulched with black polyethylene film(CP-PM), porcelain pot(POP), and plastic pot(PLP). Nine ornamental species were balsam(Impatiens balsamina), chrysanthemum(Chrysanthemum morifolium), cosmos(Cosmos bipinatus), English ivy(Hedera helix), geranium(Pelargonium zonale), kochia(Kochia scoparia var. trichophila), marigold(Tagetes patula), ornamental kale(Brassica oleraceae var. acephala), and salvia (Salvia splendens). The results obtained are summarized as follows: 1. Dry weight of all tested species grown in PLP, POP, CP-P, CP-V and CP-PI was heavier than that of CP. 2. Plant height in nine tested species grown in PLP, POP, CP-P, CP-V, and CP-PI was taller than that of CP. 3. Geranium grown in PLP, POP, CP-P, and CP-V gave more number of leaf than that of CP. 4. The number of flower in balsam grown in PLP, POP, CP-P, CP-V and CP-PI was more than that of CP. The result from marigold was very similar to this tendency. Spike length and floret number in salvia gave the same tendency, but its spike number was not different among containers used. 5. The average diurnal evaporation from PLP and POP was about 43% of that of CP. About two third of total evaporation from CP was through pot wall. 6. The evaporation rate from the slowest to the highest was PLP, POP, CP-P, CP-V, CP-PI, CP-PM and CP. Containers inhibiting evaporation through pot wall hold more soil moisture than CP from one day after water supply. 7. The more evaporative water-loss from containers gave the lower soil temperature. The variation of soil temperature among containers was higher during the day than the night. 8. The $O_2$ concentration of soil atmosphere in CP was higher than that of nonporous containers, and the difference between them was 0.40-1.12%. The range of the $O_2$ concentration 17.95~19.62%. The $CO_2$ concentration of soil atmosphere in CP was lower than that of nonporous containers, and its range was 0.59-1.76%. This deviation in soil atmosphere composition did not influenced on the growth of plants. 9. There was a possitive correlation between the amount of soil water and the plant growth. 10. Plant grown on CP gave more total nitrogen content in top growth than that on PLP. C/N ratio was somewhat low in plant on CP. From the above results, $O_2$ and $CO_2$ concentration in soil atmosphere did not gave enough deviation to the extent which affect the plant growth. The effect of soil moisture on the plant growth using different containers was the far-most significant factor from this investigation. Therefore, it was obious that the utilization of the nonporous container might save the cost for water supply and reduce the production cost of the pot-grown ornamental plant in Korea eventually.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.3 no.1
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• pp.26-27
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• 1978

It can be expected that intelligence and knowledge will be the core of the post-industrial society in a near future. Accordingly, the age of intelligence shall be accelerated extensively to find ourselves in an age of 'Communication' service enterprise. The communication actions will increase its efficiency and multiply its utility, indebted to its scientic principles and legal idea. The two basic elements of communication action, that is, communication station and communication men are considered to perform their function when they are properly supported and managed by the government administration. Since the communication action itself is composed of various factors, the elements such as communication stations and officials must be cultivated and managed by specialist or experts with continuous and extensive study practices concerned. With the above mind, this study reviewed our public service officials law with a view to improve it by providing some suggestions for communication experts and researchers to find suitable positions in the framework of government administration. In this study, I would like to suggest 'Occupational Group of Communication' that is consisted of a series of comm, management positions and research positions in parallel to the existing series of comm, technical position. The communication specialist or expert is required to be qualified with necessary scientific knowledge and techniques of communication, as well as prerequisites as government service officials. Communication experts must succeed in the first hand to obtain government licence concerned in with the government law and regulation, and international custom before they can be appointed to the official positions. This system of licence-prior-to-appointment is principally applied in the communication management position. And communication research positions are for those who shall engage themselves to the work of study and research in the field of both management and technical nature. It is hopefully expected that efficient and extensive management of communication activities, as well as scientific and continuous study over than communication enterprise will be upgraded at national dimensions.