• The Korean Journal of Mycology
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• v.3 no.1
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• pp.1-19
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• 1975

Since the importance of casing in fruit body formation of Agaricus bisporus has been emphasized, physico-chemical characteristics of casing materials were discussed by many workers and a mixture of peat and mineral soil as proper casing material has been adopted in many of mushroom growing countries. Because of limited resources of peat in Korea, it is necessary to find practical performance and substitutional materials for casing. The effect of casing on mycelial growth and mushroom yield of A. bisporus varied with materials, its combination and practices etc. The experiments to be discussed in this paper are concerned with pH and Ca of casing material which influence A bisporus, and changes of physico-chemical characteristics with mixing ratio of casing materials and its effect on A. bisporus. The optimum range of moisture content of each material, management of watering and application of physico-chemical characteristics casing materials was also investigated and re-use of weathered spent compost for casing material was described. 1. The effect of calcium on mycelial growth of A. bisporus at various pH in Halbschalentest showed different results with calcium sources. Best results were obtained around neutrality and fresh weight of fruit bodies grown in the range of pH 7 to 8 was highest among the tested levels. 2. Available moisture, pore space, organic matter, cation exchangeable capacity and exchangeable cation was increased by an increase of mixing ratio of peat in casing materials, while an adverse effect was obtained by addition of sand. 3. Mycelial growth on clay loam was more rapid at a lower bulk density of 0.75g/cc and at 20% moisture content on a dry weight basis at the same bulk density. 4. Mixing ratio of casing materials, 60 to 80 per cent by volume of peat mixed with 20 to 40 per cent of clay loam produced the highest yield of fresh fruit bodies and sand the lowest. However, per cent of open cap was highest in peat and lowest in sand. 5. Days required for fruit body initiation was shortened in mixtures of peat and clay loam by one to three days compared with other materials and the formation of flushes was clear. 6. The effect of some physico-chemical characteristics of casing materials on the fresh weight of fruit bodies were estimated by a multiple regression equation; Y=-923.86+$8.18X_1+8.04X_2+7.90X_3+0.12X_4+2.03X_5-0.82X_6-0.54X_7$ where $X_1,X_2,X_3,X_4,X_5,X_6,X_7$ are sand, silt, clay, available moistuer, porosity, organic matter and exchangeable cation respectively. The productivity of certain casing material could be predicted from this equation. 7. Fresh weight of fruit bodies was positively correlated with porosity exchangeable cation, organic matter, available moisture, silt and clay of materials; while sand was negatively correlated. On the contrary, sand was the unique factor reducing per cent of open cap. 8. Distribution of three phases of high productive casing material was concentrated in the range of 10 to 30 per cent solids, 15 to 30 per cent liquids, and 50 to 60 per cent in air volume. 9. Fresh weight of fruit bodies from peat was not affected with heavy watering but in clay loam and sandy loam severe crop losses occurred. Fresh weight of individual fruit was increased and open caps were decreased with heavy watering but light watering resulted in adverse effects: its effect was especially great in peat. 10. Optimum range of moisture content by weight on a dry basis was different with each casing material. To maintain optimum moisture content concerned with yield of fruit bodies and open cap, sandy loam and peat mixtures required daily watering of 0.6, 0.6 to 1. 2 and 1.2 to 2.4 liters per $3.3m^2$ of bed area, respectively. 11. Maximum yield of fruit body was recorded in the range of pF 2. 0 to 2. 5 of casing materials if organic matter content was below 4.2 per cent and in pF 1. 3 to 1.8 if above 7.1%. 12. pF curve of a certain casing material could be draws from moisture content at various pF values by multiple regression equations provided texture, organic matter and calcium of the casing material are given. Optimum moisture range of the casing materials also could be estimated by the equation. 13. It was possible to improve the phyico-chemical characteristics of clay loam and sandy loam by addition of weathered spent compost although the effect was less than in the case of peat. Fresh weight of fruit bodies wsa increased by addition of weathered spent compost but its effect was not as remarkable as peat. Accordingly, further studies will be required.

• The KSFM Journal of Fluid Machinery
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• v.16 no.4
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• pp.28-34
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• 2013

Centrifugal pump consists of a axis, a impeller and a spiral casing. The impeller is the most important component in centrifugal pump. But to minimize flow loss in discharge passage including spiral casing, the shape of spiral casing is very important also. So, to investigate the effect of shape of the spiral casing on performance curve of pump, the characteristics of spiral casing were studied through numerical analysis for centrifugal pump used on industry field. From the results the rectangular model was showed more loss than the others because of asymmetric flow field.

• Korean journal of applied entomology
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• v.10 no.1
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• pp.59-62
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• 1971

The highest fresh weight of Agaricus bisporus was obtained at pH 7.5 of casing soil. Above or below this pH level, the yields were significantly reduced. Stimulatory effect of calcium on the mycelial growth depended upon pH of casing soil, In neutral or slightly alkaline soil, the stimulatory effect was increased. The effects of supplementing calcium carbonate or hydrated lime to casing soil were assumed not only the influence of pH of casing soil, but also stimulatory effect of calcium ion on mycelial growth of A. bisporus.

• Mycobiology
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• v.36 no.1
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• pp.40-44
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• 2008

Various bacteria were isolated from the casing layer soil of the culture bed of P. ostreatus and their role in fruiting body induction of the edible mushroom, P. ostreatus, was investigated. Analysis of the bacterial community isolated from the casing layer soil revealed that the composition of genera and number of cultivable bacteria were different for each sterilizing treatment. Bordetella was predominant in the bulk soil whereas Flavobacterium was predominant after sterilization of the casing layer soil. Fluorescent Pseudomonas was predominant in the non-sterilized casing layer soil. Total number of the bacterial genera in the casing layer soil was higher than that in the bulk soil. In particular, an increase in the fluorescent Pseudomonas population was observed in the non-sterilized casing layer accompanied by induction of fruiting body and enhanced mushroom production yield. The results suggested that specific bacterial populations in the casing layer play an important role in the formation of primodia and the development of basidiome in P. ostreatus.

• International Journal of Fluid Machinery and Systems
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• v.9 no.2
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• pp.169-174
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• 2016

A cross-flow wind turbine has a high torque coefficient at a low tip speed ratio. Therefore, it is a good candidate for use as a self-starting turbine. Furthermore, it has low noise and excellent stability; therefore, it has attracted attention from the viewpoint of applications as a small wind turbine for an urban district. However, its maximum power coefficient is extremely low (10 %) as compared to that of other small wind turbines. In order to improve the performance and flow condition of the cross-flow rotor, the symmetrical casing with a nozzle and a diffuser are proposed and the experimental research with the symmetrical casing is conducted. The maximum power coefficient is obtained as $C_{pmax}=0.17$ in the case with the casing and $C_{pmax}=0.098$ in the case without the casing. In the present study, the power characteristics of the cross-flow rotor and those of the symmetrical casing with the nozzle and diffuser are investigated. Then, the performance and internal flow patterns of the cross-flow wind turbine with the symmetrical casings are clarified. After that, the effect of the side boards set on the symmetrical casing is discussed on the basis of the analysis results.

• Mycobiology
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• v.38 no.2
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• pp.97-101
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• 2010

Calocybe indica, a tropical edible mushroom, is popular because it has good nutritive value and it can be cultivated commercially. The current investigation was undertaken to determine a suitable substrate and the appropriate thickness of casing materials for the cultivation of C. indica. Optimum mycelial growth was observed in coconut coir substrate. Primordia initiation with the different substrates and casing materials was observed between the 13th and 19th day. The maximum length of stalk was recorded from sugarcane leaf, while diameter of stalk and pileus, and thickness of pileus were found in rice straw substrate. The highest biological and economic yield, and biological efficiency were also obtained in the rice straw substrate. Cow dung and loamy soil, farm-yard manure, loamy soil and sand, and spent oyster mushroom substrates were used as casing materials to evaluate the yield and yield-contributing characteristics of C. indica. The results indicate that the number of effective fruiting bodies, the biological and economic yield, and the biological efficiency were statistically similar all of the casing materials used. The maximum biological efficiency was found in the cow dung and loamy soil casing material. The cow dung and loamy soil (3 cm thick) was the best casing material and the rice straw was the best substrate for the commercial cultivation of C. indica.

• Smart Structures and Systems
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• v.23 no.5
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• pp.495-506
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• 2019

This paper presents the results of axial pressure testing on reinforced concrete columns (RCCs) filled with confined normal concrete (NC) and high-strength concrete (HSC) using glass-fiber reinforced plastic pipes (GRP) casing as well as fiber reinforced polymer (FRP). This study aims to evaluate the behavior and mechanical properties of columns confined with GRP casing and FRP wrapping under pressure loads. The major parameters in the experiments were the type of concrete, the effect of GRP casing and FRP wrapping, as well as the number of FRP layers. 12 cylindrical RCCs (150*600) mm were prepared and divided into two groups, NC and HSC, and each group was divided into two parts. In each part, one column was without FRP strengthening layer, a column was wrapped with one FRP layer and another column with two FRP layers. All columns were tested under concentrated compression load. The results of the study showed that the utilization of FRP wrapping and GRP casing improved compression capacity and ductility of RCCs. The addition of one and two layers-FRP wrapping increased compression capacity in the NC group to an average of 18.5% and 26.5% and to an average of 10.2% and 24.8% in the HSC group. Meanwhile, the utilization of GRP casing increased the compression capacity of the columns by 4 times in the NC group and 3.38 times in the HSC group. The results indicated that although both FRP wrapping and GRP casing result in confinement, the GRP casing resulted in increased compression capacity and ductility of the RCCs due to higher confinement. Furthermore, the confinement effect was higher on columns made with NC.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2011.04a
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• pp.97-102
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• 2011

The size of TV and TFT-LCD are bigger and bigger for the next generation exposure equipment install that existing fab are getting a lot of additions. When the new fab build an extension that the shortening of the construction and non-vibration are use cast in place concrete pile method. In this study when lay the foundation of existing fab adjoin use vibration monitoring system are rotator type all casing method among cast in place concrete pile method. The evaluation of ground vibration of rotator type all casing method effect to precision equipment and vibration area of influence.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.17 no.9
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• pp.847-852
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• 2007

Design aspects of a bearing casing system of a power plant are mainly focused on the strength and weight of itself to have a more stable system. Since the rotor speed often passes through the critical speed region when the operation begins, the relation between the rotating frequency of the rotor and natural frequency of the casing is very important for a prevention of resonance. However, harmonic components above the rotating frequency have often been overlooked the design for the resonance avoidance. In this paper, it is revealed that resonance vibration is generated when the natural frequency of a bearing casing is close to the one of harmonics of basic rotating frequency(1x), and as a consequence, sensing qualify of seismoprobes attached to the bearing casing structure can be seriously damaged. In order to reduce the resonance vibration, some stiffeners are added to the casing structures. Significant reduction in the magnitude of vibration corresponding to 2x harmonic of basic rotating frequency is observed from both FE analysis and experiment.

• Geophysics and Geophysical Exploration
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• v.20 no.4
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• pp.216-225
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• 2017

Recently, steel casing became an interesting issue when applying controlled-source electromagnetic (EM) method to various fields because effects of steel casing on EM responses are not negligible. This study employed an approach that approximates the steel casing as a series of electric dipole sources in order to develop the numerical algorithm for the efficient simulation of EM responses in the presence of steel casing. After verifying the validity of the developed algorithm, we analyze effects of steel casing on EM responses with the synthetic model simulating geothermal reservoir environment. The analysis showed that the effects of steel casing on EM responses are localized near the casing and increase as the transmitter becomes close to the casing. In addition, through the analysis on the EM responses by the injection of clean water, we confirm that the effects of casing are negligible when interpreting the after-injection data acquired using the transmitter located far enough from the casing. Considering the difference in EM responses between before and after injection in inversion, the effects of the casing can be neglected although after-injection data shows considerable difference due to the close distance between the transmitter and casing. To investigate this kind steel casing effect, the precise analysis on EM responses should be preceded. The algorithm introduced in this study will contribute to the reliable calculations of EM responses distorted by the conductive steel casing.