• The Journal of Engineering Research
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• v.4 no.1
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• pp.69-85
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• 2002

The chemical composition of bottle glass is consisted of Na2O-CaO-SiO2. However the cullet is mornally used in order to decrease the melting tsmperature. This induce the productivity of bottle and decreases the cost. The addition of plate glass decreases the Al2O3 content and in fluence the stone phenomenon and devitification in botle glass. Tus the Feldspar is added in order to increase the Al2O3 content when plate cullet was added in melting. The Tridymite crystal was observed over 7.5% Al2O3 contents, which shown as white crystal in appearance. It is Supposed that the Wollastonite Would be occurred in more over 7.5% Al2O3. This fad id well consised With the Litertctures.

• Korean Journal of Soil Science and Fertilizer
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• v.35 no.6
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• pp.372-380
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• 2002

This study was conducted to investigate the changes of soil properties for potato and Chinese cabbage after application adding phosphorus and potassium fertilizers in the mounded highland soil from 1999 to 2001. Experimental plots were designed with control(NPK+Lime+Compost) and chemical improvement(Control+Application adding P and K). Mounded soil before field experiment of first year(1999) was low in organic matter, available phosphorus and exchangeable potassium, and the soil texture was loamy sand soil. After 3 years, the contents of soil organic matter increased a little, and available phosphorus and exchangeable potassium contents were remarkably increased. The crop growth in chemical improvement plot was better than control plot. Yield of chemical improvement plot in comparison with control plot was increased by 5~22% for potato and 6~25% for Chinese cabbage after 2~3 years.

• Korean Journal of Soil Science and Fertilizer
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• v.31 no.4
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• pp.400-406
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• 1998

To investigate the effect of simulated acid rain on the change in soil chemical properties, simulated acid rain of different pH was applied to the three soils of different texture. Simulated acid rain of pH 4.0 and 6.0 did not greatly change the soil pH, while simulated acid rain of pH 2.0 decreased greatly the soil pH. Decrease in soil pH were in the order of sandy loam > loam > clay loam, while increase in exchangeable acidity was in the order of clay loam > loam > sandy loam. Amount of nutrients leached downward due to the penetration of simulated acid rain into the soil was in the order of Ca > K > Mg. Exchangeable Al was not detected when soil acidity dropped to pH 5 and exchangeable acidity increased within a range of CEC. A total 1200mm of simulated acid rain(pH 3.0) can load $12kg\;ha^{-1}$ of $H^+$ ion, $128kg\;ha^{-1}$ of sulfur, $56kg\;ha^{-1}$ of nitrogen. The acidity of simulated acid rain pH 3.0 can be neutralized by addition of $444kg\;ha^{-1}$ of slaked lime. The amount of leached bases were equivalent to 923, 1731 and $1608kg{\cdot}ha^{-1}$ in sandy loam, loam and clay loam soil respectively.

• Journal of the Mineralogical Society of Korea
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• v.20 no.4
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• pp.339-349
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• 2007

For various types of the Pungchon limestone, diverse mineral characters of the limestone including their size and morphology are investigated by using of ELS and SEM to examine the possibility of application as fillers to paper industry. Also, the measurement of zeta potential and the evaluation of coagulation properties in calcite suspension was made for fine powders of the limestone to examine the applicability and efficiency in wet-papermaking process. Fine powder of the Pungchon lime-stone, largely controlled by original mineral characters of ore in mineralogical aspects, exhibits some-what different trend in particle morphology according to ore types, and thereby, the size distribution, zeta potential and coagulation properties also become different. The examined whiteness, brightness, opacity and sheet strength in hand sheet also show remarkable differences according to ore types. These are seemed to be basically due to the results of combined effects of whiteness, site distribution, refractive index, and morphology of the limestone powder on the properties of hand sheet. Considering the investigated results, all types of the Pungchon limestone appear to be sufficiently applicable to paper industry. Especially, the mega-crystalline calcite type is evaluated to be overall suitable for the purpose of paper industry due to the higher values in whiteness and brightness. In addition the fine powder of micro-crystalline calcite type is assessed particularly to have a good quality in sheet strength by virtue of irregular particle shape.

• Conservation Science in Museum
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• v.14
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• pp.37-60
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• 2013

Conservation and analysis of wall painting Goguryeo was performed to classify the unknown fragments. The conservation naked eye observation, optical microscopy, and infrared examination were carried out in order to figure out the structure, quality of constituting materials, and damages such as cracks, and discolored fragments of colored areas. Based on such investigation, conservation was proceeded. and it was completed with strengthening the weakened pigment layer of wall blocks. In addition tombs where the wall painting fragments were excavated were investigated by making comparison with gelatin dry plates and copies possessed by National Museum of Korea. According to the result, they were Kaemachong, Gosan-ri Tomb No.1 Gamsinchong, and Wonbong-ri Tomb. The components of colors with which Goguryeo wall painting fragments were painted and the mineral pigments of the wall layer were analyzed. Portable µ-XRF spectrometer and X-ray diffractometer were employed. It showed that lime (CaCO₃) used for the wall layer, and the brown color is hematite(Fe₂O₃) and cerusite (PbCO₃) and lead oxide(PbO) were identified. In the red color, cinnabar (HgS) were detected.

• Korean Journal of Soil Science and Fertilizer
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• v.37 no.6
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• pp.383-387
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• 2004

Effects of oyster shell powder as a liming material were investigated in an apple orchard. Soil texture of the apple orchard was silty clay loam (Upyeong series with 7% of slope) and topsoil pH was 5.6. Treatments of 1,590 kg oyster shell powder $ha^{-1}$ and calcium-magnesium carbonate as much as oyster shell powder were included in the experiment. With treatments of oyster shell powder and calcium-magnesium carbonate, the length, number and diameter of new branches and the diameter of main, secondary and side branches increased in comparison with control. With oyster shell powder application, soil pH increased from 5.6 to 6.8 at the harvest. In addition, it increased exchangeable Ca from 2.6 to $4.2cmol_c\;kg^{-1}$. But it didn't make any difference in chlorophyll, sugar and malic acid contents. The apple weight per fruit of oyster shell powder application was 9 g more than that of control. Apple yield was highest ($37,000kg\;ha^{-1}$) in the oyster shell powder treatment, and the yield increase was significantly different at 5% level LSD. We concluded that the oyster shell powder can be an alternative of lime and effective to restore soil nutrient balance in apple orchard soil.

• Korean Journal of Organic Agriculture
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• v.18 no.2
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• pp.221-232
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• 2010

During 2005~2009, current status on the occurrence and the management of the major disease, insect and mite pests were investigated in the non-chemical or organic cultured apple orchards in Korea. Numbers of certified organic or non-chemical apple orchards increased from 14 in 2005 to 78 in 2008. Severe damages on leaves and fruits were caused by the several diseases such as marssonina blotch, bitter rot, white rot, sooty blotch and flyspeck, and the several insect pests such as apple leaf-curling aphid, woolly apple aphid, oriental fruit moth and peach fruit moth on the almost certified organic or non-chemical pest control orchards. About 10 and 18 environmental-friendly materials were used to control diseases and insect or mite pests, respectively. But, lime sulfur and bordeaux mixture to diseases and machine oil, plant oil mixed with egg yolk, and pheromone mating disruptions to insect pests were effective under the adequate conditions.

• Korean Journal of Organic Agriculture
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• v.22 no.3
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• pp.445-455
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• 2014

The pear sucker (Cacopsylla pyricola) is the most important insect pest in Korea. The hatching rates of overwintered adults laid eggs were observed at 10, 13, 18, and $22^{\circ}C$. The liner model was draw as Y=0.00277X+0.00146(Y=developmental rate, X=temperature) about temperature and developmental rate to eggs. The developmental threshold temperature to eggs was assumed about $-0.83^{\circ}C$. The egg hatching timing over 50% as the accumulated temperature by day maximum temperature $6^{\circ}C$ over from 1st February in 2008, 2009 and 2011 was 429.7, 417.6, and 424.3 degree $^{\circ}C$, respectively, was 3 to 7days before full blooming in pear orchard. On the other hand, the abamectin 1.8EC, lime sulfer, machine oil and 13 kinds of eco-friendly materials were not shown the control effect to the eggs. To mixed stage of pear sucker, the eco-friendly materials over 90% control value were 4 kinds such as a mixture of Azadiractin A+B, Nimbin, Salanin, Meliantriol and Vepol after twice application as 21st May and 5th June in pear growing season, in 2012.

• Journal of Korea Multimedia Society
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• v.6 no.2
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• pp.208-215
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• 2003

For playing a multimedia presentation in a Internet, the case that the presentation QoS(Quality of Services) at a destination nay be different from the QoS of multimedia data at the source occurs frequently. In this case, the process of trancoding the multimedia data at the source Into the multimedia data satisfying the QoS at the destination should be requited. In addition, even the presentation description having the homogeneous QoS at both sides may have different transcoding paths due to the limitation of display terminals or network bandwidth. That is, for a multimedia description, it is required to regenerate a proper transcoding path whenever the displaying terminals or the network environment gets decided. And the delay time required to go through the transcoding path may affect the playability of the give presentation. Therefore it should be checked whether the presentation requiring a transcoding process is able to be played in a real time. In this paper, the algorithm for generating all the possible transcoding paths for a given multimedia description under a fixed set of transcoders and the network environment is proposed. The algorithm adopts the concept of QoS transition diagram to Prevent from a trancoding Path being cycled by the repetition of a cyclic Path which generates the same QoS of multimedia data as its input QoS. By eliminating all the cyclic Paths, the algorithm can guarantee the termination of the process. And for the playability check, a method of computing the transcoding time and the delay lime between logical data units are proposed.Finally all the proposed methods were implemented in the stream engine, called TransCore and the presentation-authoring tool, called VIP, we had developed. And the test results with sample scenarios were presented at the last.

• Journal of the Earthquake Engineering Society of Korea
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• v.6 no.4
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• pp.65-73
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• 2002

It has been recognized that the damage control must become a more explicit design consideration. In an effort to develop design methods based on performance it is clear that the evaluation of the nonlinear response is required. The methods available to the design engineer today are nonlinear time history analyses, monotonic static nonlinear analyses, or equivalent static analyses with simulated nonlinear influences. Some building codes propose the capacity spectrum method based on the nonlinear static analysis(pushover analysis) to determine the earthquake-induced demand given by the structure pushover curve. These procedures are conceptually simple but iterative and time consuming with some errors. This paper presents a nonlinear direct spectrum method(NDSM) to evaluate seismic performance of structures, without iterative computations, given by the structural initial elastic period and yield strength from the pushover analysis, especially for MDF(multi degree of freedom) systems. The purpose of this paper is to investigate the accuracy and confidence of this method from a point of view of various earthquakes and unloading stiffness degradation parameters. The conclusions of this study are as follows; 1) NDSM is considered as practical method because the peak deformations of nonlinear system of MDF by NDSM are almost equal to the results of nonlinear time history analysis(NTHA) for various ground motions. 2) When the results of NDSM are compared with those of NTHA. mean of errors is the smallest in case of post-yielding stiffness factor 0.1, static force by MAD(modal adaptive distribution) and unloading stiffness degradation factor 0.2~0.3.