• Journal of Korean Society of Forest Science
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• v.56 no.1
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• pp.1-25
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• 1982

Plywood used for construction as a decorative inner material is inflammable and can cause fire accidents. causing destruction of human life and property. To diminish the fire disaster, fire retardant plywood is indeed required. In the methods of manufacturing the fire retardant plywood, a soaking method is occasionally used. However after soaking plywood into fire retardant chemical solutions redrying of soaked plywood is of the utmost importance. In this study 3.5mm and 5.0mm thickness plywoods were selected for fire retardant treatment. Treating solutions were prepared for 20% dilute solutions of ammonium sulfate, monoammonium phosphate, diammonium phosphate, borax-boric acid minalith, and water solution, 1-, 3-, 6-, and 9 hour-soaking treatments in borax-boric acid and minalith, and 6- and 9 hours in the other chemicals were applied and after the treatment hot drying was applied to treated plywoods at $90^{\circ}C$, $120^{\circ}C$ and $150^{\circ}C$ of press temperature. Drying rates, drying curves, water absorption rates of fire retardant chemicals, weight per volume and fire retardant degree of plywood were investigated. The results may be summarized as follows: 1) In the 9 hours-soaking treatment of fire retardants by hot and cold bath method, the chemical retentions of 3.5mm thickness plywood could be attained within the range ($1.125-2.25kg/(30cm)^3$) of minimum retention specification as follows: $1.353kg/(30cm)^3$ in monoammonium phosphate, $1.331kg/(30cm)^3$ in diammonium phosphate, $1.263kg/(30cm)^3$ in ammonium sulfate, $1.226kg/(30cm)^3$ in borax-boric acid. But the chemical retention, $0.906kg/(30cm)^3$, in minalith could not be attained within the range of minimum retention specification. And also in case of 5.0mm thickness plywood, chemical retentions, as $1.356kg/(30cm)^3$ and $1.166kg/(30cm)^3$ respectively, of ammonium sulfate and diammonium phosphate could be attained within the range minimum retention specification, but the other fire retardant chemicals could not. 2) In the 6- and - hours-soaking treatments of 3.5mm and 5.0mm thickness plywood, the drying curve sloped of chemical treated plywood was smaller than that of water treated. The drying rate related to thickness of treated plywood, was about three times as fast in 3.5mm thickness plywood compared with 5.0mm thickness plywood. 3) In the treatment at $120^{\circ}C$ of hot platen temperature, the drying rates of chemical-treated plywood showed the highest quantity in diammonium phosphate of 3.5mm and 5.0mm thickness plywood. But the drying rate of water treated plywood was highest during the 6- and 9 hours-soaking treatments. 4) The drying rate remarkably increased with proportion to increase of the platen temperature, and the values were respectively 1.23%/min., 6.54%/min., 25.75%/min. in hot platen temperature of $90^{\circ}C$, $120^{\circ}C$, $150^{\circ}C$ in 3.5mm thickness plywood and 0.55%.min., 2.49%/min., 8.19%/min. in hot platen temperature of $90^{\circ}C$, $120^{\circ}C$, $150^{\circ}C$ in 5.0mm thickness plywood. 5) In the fire retardant degree of chemical treated plywood, the loss in weight was the smallest in diammonium phosphate, next was in monoammonium phosphate and ammonium sulfate, and the greatest was in borax-boric acid and minalith. And the fire-retardant effect in burning time, flame-exhausted time and carbonized area were greatest in diammouniun phosphate, next were in monoammonium phosphate and ammonium sulfate, and the weakest were in borax-boric acid and minalith.

• Proceedings of the Korean Journal of Food and Nutrition Conference
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• 2001.12a
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• pp.131-131
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• 2001

The enzyme activity and organoleptic properties of Korean pickled cucumber were studies for their changes during fermentation. The Korean pickled cucumber were prepared by blanching and high temperature soaking in salt solution and trehalose treatment The results shelved that the effect of combined heat and trehalose treatment significantly reduced the fermentation rate and softening rate of texture while a rather rapid fermentation was for those pleserved with salt. The effect of trehalose treatment enhenced fermentation and it was significantly reduced softening rate of texture by 2% treatment. The sensory evaluation of Korean pickled cucumber was found that combined heat treatment with blanching and hot solution had a positive effect for reduction of softening of cucumber tissue, however, odor and taste were not significantly affected. This study suggested that combined heat and trehalose treatment might have potential for affording protection against softness of cucumber tissue during the fermentation time.

• Journal of the Korean Society for Heat Treatment
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• v.11 no.3
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• pp.200-206
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• 1998

The aim of this study is to investigate the effect of impurity level and fabrication processes on the strength, impact and fracture toughness of 7075, 7050 and 7175 aluminum alloy forgings. A specially processed 7175S-T74 aluminum forgings was superior to a conventionally processed 7075-T73, 7050-T74 and 7175-T74 aluminum forgings in both strength and toughness. The reduction of impurity level of iron and silicon has significantly diminished the size and volume fraction of second phase particles such as $Al_7Cu_2Fe$ and $Mg_2Si$. A further reduction of the amount of second phase particles has been observed by applying a special fabrication process. This phenomena result from the application of intermediate soaking at higher temperature and more sufficiant hot working temperature than that of a conventional processing.

• The Korean Journal of Food And Nutrition
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• v.30 no.3
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• pp.560-567
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• 2017

In this study, we investigated the quality characteristics and optimum conditions of porridge containing rice incubated with Phellinus linteus mycelium (PLMR). Composition measurements of PLMR were moisture 13.05%, ash 0.88%, carbohydrate 78.65%, crude protein 6.29%, and crude lipid 1.13%, also glutinous rice composition was moisture 13.99%, ash 0.32%, carbohydrate 77.18%, crude protein 7.85%, and crude lipid 0.66%. The water absorption rate of PLMR increased with increasing soaking time during 6 hours. However, the water absorption rate of glutinous rice increased until 30 minutes of soaking time. The pH of porridge was decreased as PLMR contents increased. The viscosity of porridge was increased as PLMR contents increased, and it was the lowest for the control at 914.77 cP. However, spreadability of porridge was decreased as PLMR contents increased. In terms of color, lightness was the highest for the 50% level, redness was the highest for the 75% level, and yellowness was the highest for the 25% level. In terms of textural characteristics, hardness and fracturability were increased as PLMR contents increased, whereas springiness, cohesiveness and resilience showed reverse results. In terms of consumer acceptance, flavor, appearance, viscosity, delicate taste, and overall acceptability were not significantly different between samples. Hot taste was decreased as PLMR contents increased, whereas grittiness showed reverse results. In conclusion, the results indicate that adding 25~50% PLMR to porridge is optimal for a recipe.

• Korean Journal of Food Science and Technology
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• v.21 no.6
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• pp.845-850
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• 1989

Effect of high temperature soaking in salt solution and short time microwave heat treatment on quality of Korean pickled cucumbers during fermentation was investigated. The Korean pickled cucumbers were fermented at $25^{\circ}C$ for 10 days in 10% salt solution. The physicochemical properties measured were pH, the total acidity, hardness and the sensory properties of odor, taste and texture were also evaluated. The result showed that the effect of soaking cucumber in $80-90^{\circ}C$ hot salt solution significantly reduced the fermentation rate and softening rate of texture while a rather rapid fermentation was found for those soaked in $60-70^{\circ}C$. The effect of microwave treatment inhenced fermentation a little for short treatment but it was significantly reduced softening rate of texture by 3 minutes heating. The sensory evaluation of Korean pickled cucumber was found that heat treatments with hot solution and microwave heating had a possitive effect for reduction of softening of cucumber tissue, however odor and taste were not significantly affected.

• Korean journal of food and cookery science
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• v.18 no.1
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• pp.101-108
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• 2002

This study aimed to determine the effects of cooking treatment on chromaticity and 6 mineral contents (calcium, phosphorus, magnesium, iron, sodium and potassium) in sea mustards. Four samples of natural and cultured sea mustard were used for the experiments. Each sample was treated with four cooking methods (A: soaked in water, B: boiled in hot water, C: saute and boiled in hot water, D: seasoned with vinegar). The L, a and b values were the highest on boiling, and the lowest on seasoning with vinegar. The a value of cultured sea mustard was higher than the natural one by cooking. Moisture was highest boiling and were ordered as saute and boiling, soaking and seasoning with vinegar. Calcium, iron, magnesium and phosphorus contents were remarkably decreased by seasoning with vinegar. Boiling treatment made less decrease than saut and boiling in these mineral contents. The solubilities of mineral in soup water were recognized therefore, it indicated that soup water was a good source of minerals as it applies to cooking, from the view point of science of cookery. Sodium and potassium contents decreased significantly more at 68% and 85% of total content on basic soaking treatment. Ca/P ratio was about 1∼3 : 1 in cultured sea mustard and 3∼4 : 1 levels in natural one.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.6 no.1
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• pp.17-27
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• 1996

This study was designed to survey exposure levels of formaldehyde among workplaces in some plywood industries and to compare three sampling methods including the impinger method(IM, NIOSH method No. 3500), the solid sorbent tube method(SS, NIOSH method No. 2541), and the passive bubbler monitor method(PB, SKC). The survey was conducted in seven particle board manufacturing factories, two resin manufacturing factories and two plywood manufacturing factories in Incheon area during the period from March 6 to April 20, 1995. The workplaces included were the hot/cold press, the roller/spreader, the soaking/drying, and the reaction/mixing areas. The results were as follows; 1. The average(GM, GSD) concentrations of formaldehyde by sampling methods were 0.11(4.43) ppm by IM, 0.27(2.03) ppm by SS, and 0.29(2.04) ppm by PB, respectively. The concentrations by 1M method were statistically very significantly lower than those of SS and PB methods, particularly at low air borne concentrations of formaldehyde (p<0.001). 2. The area average concentrations of formaldehyde by workplaces measured with PB bubblers were 0.23(2.08) ppm from the press, 0.23(1.77) ppm from the spreader, 0.24(1.51) ppm from the soaking, and 0.46(1.96) ppm from the reaction areas, respectively. The personal average concentrations of formaldehyde by workplaces measured with PB bubblers were 0.30(1.77) ppm from the press, 0.33(1.54) ppm from the spreader, 0.36(1.46) ppm from the soaking, and 0.84(1.19) ppm from the reaction areas, respectively. 3. No statistically significant differences of formaldehyde concentrations among workplaces except the reaction area(p<0.001) were found. 4. Formaldehyde concentrations from personal samples were higher than those of from area sam pies in all workplaces studied. But no statistically significant differences of formaldehyde concentrations both area and personal samples were found. In conclusion, this study found that although formaldehyde concentrations in some plywood industries in Incheon area were below the regulatory limit of 1 ppm, they were over the limits recommended by NIOSH and ACGIH. This study also suggests that the impinger method may underestimate true formaldehyde concentrations. It implies that there will be more workplaces not meeting current regulatory limit if either the solid sorbent or passive bubbler methods were used instead of the impinger method. It is suggested that passive monitors will be a reasonable alternative for area and personal sampling of formaldehyde if the accuracy and validity of passive monitors be verified before use.

• Journal of the Korean Wood Science and Technology
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• v.9 no.3
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• pp.16-23
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• 1981

This study has been carried out to make a comparative study for the adhesive control methods specifically developed for application to formaldehyde. The method for formaldehyde determination used in this report is the improved chromo tropic acid determination. The results are summarized as follows: 1. The soaking treatment in aqueous solution of urea wok the most scavenging effect on the formaldehyde release from a plywood sample glued with a urea formaldehyde adhesive, and other removal treatment such as resorcinol, albumine-, and hardener-treatment gave significant reduction too. 2. In glue shear strength of dry test, 2% of resorcinol treatment and soaking treatment showed the highest strength and all the other treatment met the standard, but in hot water soaking test, 2% of resorcinol treatment gave the best results, on the other hand, adding the hardener showed the lowest strength and failed in meeting the standard. 3. Air dried moisture content of all treated plywood met the standard which calls for 13% or bellow. 4. In this comparative study, we can make a strong combination each other or go into the details of one treatment for the best result through the more study.

• Korean Journal of Heritage: History & Science
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• v.57 no.1
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• pp.110-123
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• 2024

Onyanghaenggung Palace(temporary palace at Onyang) is an important cultural heritage that can substantially confirm the king's visiting at hot springs based on literature records such as <Ongungyeonggoedae(溫宮靈槐臺)>, <Oncheonhaenggungdo(溫泉行宮圖)> of 『Ongungsasil(溫宮事實)』, <Younggoedaedo(靈槐臺圖)>, 『Younggoedaegi(靈槐臺記)』 and cultural properties such as Yeonggoedae(靈槐臺) and Shinjeong Monument(神井碑). Through a photo taken by Hermann Sander in 1906, it can be confirmed that the hot springs(Tangsil building) at Onyanghaenggung Palace during the Joseon Dynasty was maintained until the early Japanese colonial period. The purpose of this study is to estimate the compositions of the hot springs(Tangsil building) in Onyanghaenggung Palace based on literature records and <Oncheonhaenggungdo>(1795). To achieve these purposes, we firstly examined the changes in Onyanghaenggung Palace and the hot springs (Tangsil building); secondly, the bathing behaviors of kings were reviewed; thirdly, we organized the architectural composition of the hot springs (Tangsil building) according to "Ongung Repair" of 『Ongungsasil (溫宮事實)』; and fourthly, by comparing Sander's photo in the early days of Japanese colonial rule, the architectural composition of the hot springs (Tangsil building) in the late Joseon Dynasty was examined. The results of this study are as follows. First, the hot springs(Tangsil building) of Onyanghaenggung Palace were continuously connected to the Onjeongsil(溫井室) in the reign of King Hyeonjong and maintained until 『Hoseo-eupji』 (1871) in the late Joseon Dynasty. It matches the photograph taken by Hermann Sander(1906) and <1912 Onyang Hot Springs in Asan City>(1912) of Korea Copyright Commission during the early Japanese colonial period. Second, the various king's bathing methods during the Joseon Dynasty were adopted such as washing, spilling and bathing head while sitting on a bathing platform or chair, or exposing the steam of hot spring water, dipping feet into the water and a half-body soaking bath below the navel immersed in water. Third, the stone bathtubs of hot springs(Tangsil building) are composed of the upper bath which was hot spring water gushes out from the northwest, bends to the east, enters the middle bath, and bends to the south to come out to the outside to gather in the lower bath. Around the stone bathtubs, pebble stones brought in from Taean were laid on the floor of the hot springs(Tangsil building). From the above considerations, the compositions of the Tangsil building in Onyang Temporary Palace is based on the king's approach from the main royal building, the king's bathing method and bathing tools, the bathing behavior of enlisted medical officers and bathing assistants, and each rooms mentioned in "Ongung Repair". By comparing it with Hermann Sander's photo, the architectural compositions of the hot springs(Tangsil building) can be estimated.

• The Korean Journal of Food And Nutrition
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• v.14 no.5
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• pp.385-390
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• 2001

The enzyme activity and organoleptic properties of Korean pickled cucumber were studies for their changes during fermentation. The Korean pickled cucumber were prepared by blanching and high temperature soaking in salt solution and trehalose treament. The results showed that the effect of combined heat and trehalose treatment significantly reduced the fermentation rate and softening rate of texture while a rather rapid fermentation was for those preserved with salt. The effect of terhalose treatment enhanced fermentation and it was significantly reduced softening rate of texture by 2% treatment. The sensory evaluation of Korean pickled cucumber was found that combined heat treatment with blanching and hot solution had a positive effect for reduction of softening of cucumber tissue, however, odor and taste were not significantly affected. This study suggested that combined heat and trehalose treament might have potential for affording protection against softness of cucumber tissue during the fermentation time.