• Journal of Bio-Environment Control
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• v.23 no.2
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• pp.95-108
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• 2014

The objective of this study is to develop the plastic greenhouse models which are structurally safe under the weather condition of Seongju and have the dimensions suitable for oriental melon cultivation as well. To grasp the structural features of greenhouses in Seongju, the field survey was conducted on 406 farmhouses which included 2,068 greenhouses. The field survey showed that the roof shape of arch type accounted for the highest rate, but recently even span or peach type became more popular and the width and height of greenhouse tended to increase as the period of use was short. The relationship of the width, ridge height and eaves height were established based on field survey data. Using climate data of Gumi adjacent to Seongju, the regressions were determined for the design wind speed and design snow depth depending on recurrence period. To design the greenhouse models against weather disasters in Seongju, the optimal design loads are 23.7 cm of snow depth and $33.8m{\cdot}s^1$ of wind speed. As the design results, four models of single-span greenhouse, two models of double-span greenhouses including extension were developed.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.8
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• pp.1127-1132
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• 2000

Forty yearling Tswana sheep and goats (20 sheep and 20 goats) of both sexes were used in a feeding trial conducted in Botswana College of Agriculture (B.C.A) Content Farm in Gaborone for three months. The animals were randomized into four treatment groups of five animals per species balancing for weight and sex such that average initial weights were not statistically different. The sheep and goats were individually housed and fed under a common roof. All the animals were fed on Lablab purpureus L. as a protein supplement which was 40% of the ration. In addition to L.purpureus L. the control groups of both species were fed on 60% Cenchrus ciliaris L. as basal diet. The other three treatment groups were fed on different forages namely; sorghum forage (Sorghum sudanense (Piper) Stapf), millet forage (Pearl millet, Pennisetum typhoides (Burm.) Stapf and Hubb.) and veldt grass mainly Urochloa mosambicensis (Hack.) as basal diet (60%). Water was provided individually to all the animals on ad lib. basis. Daily intakes of feed and water were recorded and weighing of the animals was done every two weeks. The collected data were analysed statistically for differences. Average daily weight gain by Tswana sheep was significantly different (p<0.05), sheep fed on millet forage had a higher daily weight gain $(120.24{\pm}8.91g)$ compared with sheep fed on veldt grass $(92.86{\pm}6.94g)$. Treatment effects on daily total DM intake by sheep were significant, the control group (C. ciliaris L.) had higher intake $(705.77{\pm}10.22g)$ and those fed on sorghum forage had the least intake $(668.10{\pm}10.70g)$. There was no significant difference (p>0.05) in the average daily weight gain by Tswana goats and it was 84.52, 73.81, 83.33 and 78.57 g for goats fed on C. ciliaris L., sorghum forage, millet forage and veldt grass respectively. Average daily total DM intake by goats was 655.27, 652.64, 650.07 and 650.94 g for C. ciliaris L., sorghum forage, millet forage and veldt grass respectively. Feed conversion efficiency was 8.00, 8.98, 7.93 and 8.34 for goats fed on C. ciliaris L., sorghum forage, millet forage and veldt grass respectively and were not significantly different (p>0.05).

• Journal of Bio-Environment Control
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• v.28 no.4
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• pp.388-395
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• 2019

The purpose of this study is to suggest structural model and analyze design factors for the development of small greenhouse standardization model. The average dimensions of small greenhouse desired by urban farmers were 3.3m in width, 1.9m in eaves height, 2.7m in ridge height, 5.7m in length. The cladding materials for small greenhouse were preferred to glass, PC board and plastic film, framework to aluminum alloy and steel, and heating method in electrical energy. In addition, it was analyzed that small greenhouses need to develop structural model by dividing them into entry-level type and high-level type. The roof type that was used for entry-level type was arch shape, framework was steel pipe, cladding material was plastic film. On the other hand, high-level type was used in even span or dutch light type, framework with square hollow steel, cladding materials with glass or PC board. In consideration of these findings and practicality, this study developed four types of small greenhouses. The width, eaves height, ridges height, and length of the small greenhouses of even span type, which were covered with 5mm thick glass and 6mm thick PC board were 3m, 2.2m, 2.9m, and 6m, respectively. The small greenhouse of dutch light type covered with 5mm thick glass was designed with 3.8m in with, 2.2m in eaves height, 2.9m in ridges height, and 6m in length. The width, eaves height, ridges height, and length of the arch shape small greenhouse covered with a 0.15mm PO film were 3m, 1.5m, 2.8m, and 6m, respectively.

• Journal of Bio-Environment Control
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• v.13 no.4
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• pp.217-225
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• 2004

This study was performed to provide the basic knowledge about the mushroom cultivation facilities. Classified current status of cultivation facilities in Gyeongnam province was investigated by questionnaire. The structure of Pleurotus eryngii cultivation facilities can be classified into the simple and permanent frame type. The simple frame structures were mostly single-span type, on the other hand, the permanent frame structures were more multi-span than simple structures. And the scale of cultivation facilities was very different regardless of structural type. But as a whole, the length, width and ridge height were prevailing approximately 20.0 m, $6.6\~7.0m$ and $4.6\~5.0m$ range, respectively. The floor area was about $132\~160\;m^2$, and floor was built with concrete to protect mushrooms from various harmful infection. The roof slope of the simple and permanent type showed about $41.5^{\circ}\;and\;18.6\~28.6^{\circ}$, respectively. The width and layer number of growing bed for mushroom cultivation were around $1.2\~1.6m$, 4 layers in common, respectively. Most of year round cultivation facilities were equipped with cooler, heater, humidifier, and ventilating fan. Hot water boiler was the most commonly used heating system, the next was electric heater and then steam boiler. The industrial air conditioner has been widely used for cooling. And humidity was controlled mostly by ultra-wave or centrifuging humidifier. But some farmers has been using nozzle system for auxiliary purpose. More then $90\%$ of the mushroom house had the independent environment control system. The inside temperature was usually controlled by sensor, but humidity and $CO_2$ concentration was controlled by timer for each growing stage. The capacity of medium bottle was generally 850 cc and 1100cc, some farms used 800 cc, 950 co and 1,250 cc. Most of mushroom producted has been usually shipped to both circulating company and joint market.

• Research in Plant Disease
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• v.14 no.1
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• pp.51-56
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• 2008

Powdery mildew of lettuce that is a newly reported disease became a threat to organic cultivation of lettuce in Korea since the disease caused by Podosphaera fusca resulted in a half of yield loss in heavily infected fields. To improve micro-environmental conditions around lettuce, ACF (air-circulation fan) was installed on inside roof of plastic house at 6 m intervals. The ACF increased 57% of lettuce yield and reduced 71.4% of lettuce seedling death. COY (cooking oil and yolk mixture) consisted of cooking oil 0.3% and egg yolk 0.08% reduced lettuce seedling death from 89.3% to 92.9% under the greenhouse. Seven-day interval spray of COY resulted in high control values of powdery mildew of lettuce ranging from 89.6% to 96.3%, which was comparable to a fungicide, Azoxystrobin. Lettuce yield was increased about two times compared to a non-treated conventional cultivation. Qualities of lettuce such as hardness and chlorophyll content were also improved by COY and ACF combination. Effect of COY on control of the disease was improved when $CaCO_3$ or $SiO_2$ 1,000 ppm was supplemented. Results indicated that the COY made of cooking oil such as canola emulsified with yolk was highly effective on control of powdery mildew of lettuce and suitable for organic agriculture, especially when combined with ACF.

• Smart Structures and Systems
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• v.20 no.1
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• pp.61-74
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• 2017

One of the most reliable and simplest tools for structural vibration control in civil engineering is Tuned Mass Damper, TMD. Provided that the frequency and damping parameters of these dampers are tuned appropriately, they can reduce the vibrations of the structure through their generated inertia forces, as they vibrate continuously. To achieve the optimal parameters of TMD, many different methods have been provided so far. In old approaches, some formulas have been offered based on simplifying models and their applied loadings while novel procedures need to model structures completely in order to obtain TMD parameters. In this paper, with regard to the nonlinear decision-making of fuzzy systems and their enough ability to cope with different unreliability, a method is proposed. Furthermore, by taking advantage of both old and new methods a fuzzy system is designed to be operational and reduce uncertainties related to models and applied loads. To design fuzzy system, it is required to gain data on structures and optimum parameters of TMDs corresponding to these structures. This information is obtained through modeling MDOF systems with various numbers of stories subjected to far and near field earthquakes. The design of the fuzzy systems is performed by three methods: look-up table, the data space grid-partitioning, and clustering. After that, rule weights of Mamdani fuzzy system using the look-up table are optimized through genetic algorithm and rule weights of Sugeno fuzzy system designed based on grid-partitioning methods and clustering data are optimized through ANFIS (Adaptive Neuro-Fuzzy Inference System). By comparing these methods, it is observed that the fuzzy system technique based on data clustering has an efficient function to predict the optimal parameters of TMDs. In this method, average of errors in estimating frequency and damping ratio is close to zero. Also, standard deviation of frequency errors and damping ratio errors decrease by 78% and 4.1% respectively in comparison with the look-up table method. While, this reductions compared to the grid partitioning method are 2.2% and 1.8% respectively. In this research, TMD parameters are estimated for a 15-degree of freedom structure based on designed fuzzy system and are compared to parameters obtained from the genetic algorithm and empirical relations. The progress up to 1.9% and 2% under far-field earthquakes and 0.4% and 2.2% under near-field earthquakes is obtained in decreasing respectively roof maximum displacement and its RMS ratio through fuzzy system method compared to those obtained by empirical relations.

• Magazine of the Korean Society of Agricultural Engineers
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• v.28 no.2
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• pp.31-41
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• 1986

Knowledge of the degree of yield reduction due to water stress at different crop growth stages in rice production is important for rational scheduling of irrigation during periods of insufficient water supply. Previous studies to determine the degree of yield reduction duo to water stress suffered from interruptions by rain during experiment. Also the findings did rot relate the degree of water stress to the soil water potential and water deficit status of rice plants. In this study, two years experiments were conducted using the high yielding rice varieties, an Indica x Japonica (Nampoong) and a Japonica variety(Choochung). These were grown in 1/200$^{\circ}$ plastic pots placed under a rainfall autosensing, sliding clear plastic roof facility to control rainfall interruptions. The results obtained were as follows. 1.The two varieties differed in the growth stage most sensitive to water stress as well as the degree of yield reductions. When rice plants were stressed to the leaf rolling score 4 and soil water potential of about - 20 bar at major crop growth stages which included heading, booting, non-effective tillering, panicle initiation and early tillering stages, the yield reductions in the Indica x Japonica variety were 58%, 34%, 27%, 22%, and 21%, respectively, whereas in the Japonica vairety they were 23%, 36%, 1%, 13% and 22%, respectively. This result show that the recommended drainage during non-effective tillering is valid only for the Japonica variety. Sufficient irrigation at booting, heading and early tillering stages are necessary for both varieties. 2.The two varieties showed visible wilting symptoms when the soil water potential dropped to about - 3.0 bar. The Japonica variety showed more leaf rolling than the Indica X Japonica. However, it had a higher retention of leaf water content and greater stomatal diffusive resistance. When the soil water potential dropped, the Japonica variety showed leaf rolling score (LRS) 1 at 0 soil-5. 0 bar and LRS 2 at 0 soil -6.0 bar while the Indica X Japonica showed LRS 1 at 0 soil - 5.5 bar and LRS 2at 0 Soil - 9.0 bar. The stomatal diffusive resistance was maximum at the second top leaf blade in both varieties at intermediate water stress of 0 soil - 4.5 bar. 3.The number of days that was required for the soil water potential to drop to-3. 0 bar and to - 20.0 bar after drainage of irrigation water from the 20cm deep silty clay loam soil in the pots were 6 and 13 days, respectively for booting stage, and 7 and 11 days, respectively for heading stage, 9 and 12 days, respectively for panicle initiation stage, and 12 and 19 days, respectively for early tillering stage. 4.Water stress during the early tillering stage recorded the longest delay in beading time, the largest reduction in panicle numbers and a substantial yield decrease of 20%. This calls for better water management to ensure the availability of water at this stage, particularly during drought periods. In addition, a reexamination of the conventional inter-drainage practice during the non-effective tillering stage is necessary for the high yielding Indica X Japonica varieties.

• Journal of Conservation Science
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• v.18 s.18
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• pp.63-74
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• 2006

All rock materials of the three storied stone pagoda in Seoakri were composed of light gray alkali granite with medium grained and developed with small mialolitic cavities. This stone pagoda is preserving almost archetype except the head part because there was repair work already. But, foundation, basement and roof rocks are serious state by microbial invasion such as lichens. Because there are tree and grass that cause direct effect to stone pagoda surrounding. Therefore, conservation treatment executed the primary dry cleaning and secondary wet cleaning treatment. Stone surface is partly not removed well such as lichens which part removed using cleansing device that use high temperature steam. Some treated part concrete and epoxy resin remove and retreatment with mixing talc and alkali granite powder to epoxy resin. Did color matching at mixing process of epoxy resin and fillers to properties with set the feel of a material. Also, drainage ditched to minimize inflow of rainwater fall from slope that is on the east of stone pagoda, tree and grass in stone pagoda surrounding wished to do remove and control occurrence of lichens hereafter minimizing moisture conteats.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.6
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• pp.3983-3989
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• 2014

As the storm water runoff characteristics in urban areas have changed owing to urbanization, centralized facilities to reduce the urban flood runoff had been implemented. On the other hand, because they have their limitations, LID (Low Impact Development) of the distributed facilities for storm water runoff reduction is being actively planned and applied. The purpose of this study was to analyze the runoff characteristics for the spatial distribution of typical LID element techniques. This study set a study basin consisting of the five subbasins with the same basin and drainage systems, and analyzed the flood runoff characteristics from the two scenarios, one is for the locations and the other is for the number of green roofs (GR) and permeable pavement (PP), respectively, selected as typical LID element techniques. The SWMM implementation results showed that GR reduces 11.07% of the total and 3.42% of the peak amounts of storm water runoff, and PP leads to 18.09% of the total and 17.94% of the peak discharge reduction for a subbasin. Such a reduction rate is constant regardless of the LID locations, and increases linearly with the number of LID applications. The different runoff reduction rates between the GR and PP applications appear to be due to the effects of the different hydraulic conductivities in the control parameters for each LID.

• Journal of architectural history
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• v.12 no.1 s.33
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• pp.25-41
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• 2003

This paper is a study of Le Corbusier's trace regulateur of the 1920s, particularly its role in the design of the Villas La Roche-Jeanneret and Stein-de Monzie. It proceeds on the basis of the following three themes: first, the relation between the regulating line and the dom-ino frame; second, its status as a proportional device based not on a module system but one that defines relations; third, its function as an essential practical device in the design process. In the Villa La Roche-Jeanneret, the embedded horizontal planes of the dom-ino frame were constant, but the vortical lines of the columns were altered according to the changes in plan. Initially, a left-hand bay window formed a symmetry with the right-hand bay window, the only constant in the design process. With subsequent changes, mullion sections of the horizontal window and roof elements came to provide the reference points for the regulating line. Eventually, a regulating line different from the one that controlled the bay window and the elongated volume came to control the entrance hall of Villa La Roche, resulting in three different kinds of regulating lines in the final version. In contrast to the Villa La Roche-Jeanneret, a singular and consistent regulation line was anticipated in the earliest design stages of the Villa Stein-de Monzie. The repetition of its A:B grid and the standard $2.5m{\times}1.0m$ sliding window determined the proportions of both its plan and elevation, and thus the regulating line became 'automatic,' losing its viability as a practical tool. Though the regulating titles of the La Roche-Jeanneret look as if they were an afterthought, drawn after the design was complete, they were most active, requiring tenacity and discipline in their application. On the other hand, the seemingly 'redundant' regulating line of the Villa Stein-de Monzie gains its raison d'etre from the dom-ino frame. Its cantilevers and uninterrupted horizontal window could be used in decisive fashion because of the guarantee that the correct proportion would always be maintained. Thus we discover that Le Corbusier's discipline of the 1920s had a certain spectrum of flexibility. His 'parti' ranged from the extremely loose and malleable grid of the Villa La Roche-Jeanneret to the fixed grid of the Villa Stein-de Monzie. In different ways, these projects retain the tension between the dom-ino frame and the regulating line. For Le Corbusier, as much as the grid was an object with fixed attributes, it was also an active medium manipulated by the will of the architect.