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A Experimental Study on Exclusion Ability of Riprap into Bypass Pipe (저층수 배사관 내 유입된 사석 배출능력에 대한 연구)

  • Jeong, Seok Il;Lee, Seung Oh
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.37 no.1
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    • pp.239-246
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    • 2017
  • There are various transversal structures (small dams or drop structures) in median and small streams in Korea. Most of them are concrete structures and it is so hard to exclude low-level water. Unless drainage valves and/or gates would not be installed near bottom of bed, sediment from upstream should be deposited and also contaminants attached to the sediments would devastatingly threaten the water quality and ecosystem. One of countermeasures for such problem is the bypass pipe installed underneath the transversal structure. However, there is still issued whether it would be workable if the gravels and/or stones would roll into and be not excluded. Therefore, in this study, the conditions to exclude the rip stone which enter into the bypass pipe was reviewed. Based on sediment transport phenomenon, the behavior of stones was investigated with the concepts from the critical shear stress of sediment and d'Alembert principle. As final results, the basis condition (${\tau}_c{^*}$) was derived using the Lagrangian description since the stones are in the moving state, not in the stationary state. From hydraulic experiments the relative velocity could be obtained. In order to minimize the scale effect, the extra wide channel of 5.0 m wide and 1.0 m high was constructed and the experimental stones were fully spherical ones. Experimental results showed that the ratio of flow velocity to spherical particle velocity was measured between 0.5 and 0.7, and this result was substituted into the suggested equation to identify the critical condition wether the stones were excluded. Regimes about the exclusion of stone in bypass pipe were divided into three types according to particle Reynolds number ($Re_p$) and dimensionless critical shear force (${\tau}_c{^*}$) - exclusion section, probabilistic exclusion section, no exclusion section. Results from this study would be useful and essential information for bypass pipe design in transveral structures.

Effect of Aqueous Phase Composition on the Stability of a Silica-stabilized Water-in-oil Emulsion (유화제로서 실리카를 이용한 유중수형 에멀젼의 안정성에 미치는 수상부 조성의 영향)

  • Kim Jin-Hwang;Kim Song-I;Kyong Kee-Yeol;Lee Eun-Joo;Yoon Moung-Seok
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.30 no.3 s.47
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    • pp.353-359
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    • 2004
  • The extent of silica flocculation can be modified by varying the silica concentration, aqueous phase pH, salt and polvmer concentration. High volume fraction W/O emulsion stabilized by hydrophobic silica was established with various aqueous phase conditions for cosmetic application. By increasing the silica concentration up to $1.0\;wt\%,$ the size of droplet decreased. A high silica concentration increased the viscosity of continuous oil phase by network formation, which resulted in target size of droplet. The stability of W/O emulsion is improved as increasing the aqueous phase pH. At low and intermediate pH, the emulsions became more stable by adding salt $(0.083\;mol\;dm^{-3}\;MgSO_4).$ At high PH, the presence of salt caused significant destabilization. The gelation behavior of the emulsion indicates that the effect of salt on silica-stabilized emulsion is derived from an electrostatic attraction. The addition of xanthan gum in aqueous phase increased the mono-dispersity of the W/O emulsion by making water more hydrophobic and hindering the recombination of droplets. In conclusion, these results indicate that very stable emulsifier-free, finely dispersed W/O emulsion can be achieved for cosmetic application by changing the aqueous phase composition.

Effect of ${\alpha}-Amylase$ Treatment of Brown Rice(Goami) Alcohol Fermentation By-Product (현미(고아미) 알코올발효 부산물의 ${\alpha}-amylase$처리 효과)

  • Woo, Seung-Mi;Kim, Tae-Young;Yeo, Soo-Hwan;Kim, Sang-Burm;Kim, Mi-Hyun;Woo, Sang-Chel;Jeong, Yong-Jin
    • Food Science and Preservation
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    • v.14 no.6
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    • pp.617-623
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    • 2007
  • To utilize the non-heat treated alcoholic by-products of brown rice(Goami) as food sources, the quality characteristics change according to the treatment conditions of ${\alpha}-amylase$ were evaluated. It resulted that the increase of hydrolysis temperature correspondingly increased the soluble solids, total dietary fiber and total sugar in the by-products of Goami, and the highest reducing sugar content was observed at $80^{\circ}C$. The free amino acids contents were tended to slowly decrease by the hydrolysis temperature more than $70^{\circ}C$, and the highest content of oligosaccharides were detected at the hydrolysis temperature of $80^{\circ}C$. The soluble solid according to the ${\alpha}-amylase$ concentration resulted to increase with the increase of the enzyme concentration and the total dietary fiber revealed similarly showing approximately 0.65%. The high content of reducing sugars was observed at the enzyme concentration around 0.08%(v/w). Total sugars and oligosaccharides contents tend to increase as the concentration of enzyme increased, and the content of oligosaccharides acquired at the enzyme concentration more than 0.10%(v/w) maintained to show rather similar contents. The soluble solids and total dietary fiber by hydrolysis time were found to show 6.66% and 0.65%, respectively at more than 60 min of hydrolysis, and the reducing sugars and total sugars were found to be 3,600 and 4,800 mg% in all treatment groups showing no significant difference. The content of oligosaccharides was increased with the increase of hydrolysis time, and the content was similar at more than 90 min of hydrolysis by ranging around 2,100 mg%. Based upon these results, the by-products of Goami are expected to be used as various food sources showing the highest dietary fiber and oligosaccharides contents by the hydrolysis at $80^{\circ}C$ for 90 min with the addition of 0.10%(v/w) of ${\alpha}-amylase$.

Removal Efficiency of the Deodorization Equipment and Characteristics of Malodor during the Process in Co-treatment of Sewage and Food Waste of Su-young Wastewater Treatment Plant in Busan (부산수영하수처리장 하수와 음식물쓰레기 병합처리 시 공정별 악취특성 및 후처리시설 효율평가)

  • Lee, Hyung-Don;Kang, Dae-Jong;Lee, Min-Ho;Kang, Dong-Hyo;Oh, Kwang-Joong
    • Clean Technology
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    • v.18 no.4
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    • pp.379-389
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    • 2012
  • Environmental issues are being paid more attention due to income growth, urban overcrowding, and population growth in Korea. Among the various environmental problems, odor damage is the one of the serious factors. To take example for food waste combination treatment in Su-young wastewater treatment plant in Busan, many complaints occurred because this plant locate around residential areas. The purpose of this work is not only to analyze odorous elements and their contributions but also to evaluate odor quotient (OQ), sum of odor quotient (SOQ), and treatment efficiency of bio-filter. The results of dilution sensory test of complex odor, grinder, leachate, hopper indicated higher order complex odors happen in July and August. The main odorous elements consisted of hydrogen sulfide, ammonia, methly mercaptan and acetaldehyde, which were analyzed by instrumental detection method, and methyl mercaptan was exceeded over 3,571 times of threshold. In addition, result of contribution of odor was methyl mercaptan (49.95 to 59.08%), hydrogen sulfide (20.43 to 29.27%), trimethylamine (8.82 to 13.42%) and acetaldehyde (9.17 to 11.35%). Other facilities were compared with the contribution of the odor using OQ and SOQ during the process. Sulfur compounds, acetaldehyde, and trimethylamine are high contribution of odor using OQ as well as odor intensity of grinding process is highest. As a result, sulfur compounds (e.g., methyl mercaptan and hydrogen sulfide) are highest for OQ and SOQ of grinding process is highest as 7,067. The removal efficiency of deodorization equipment was more than 90.00% in ammonia and amines, but the average efficiency of sulfur compounds was 53.51%. Thus, this facility is more higher contribution of acetaldehyde and trimethylamine than other treatment facilities. And food waste treatment in environmental area needs to consider appropriate capacity and refers to other bio-filter operating conditions.

A STUDY ON THE MEASUREMENT OF THE IMPLANT STABILITY USING RESONANCE FREQUENCY ANALYSIS (공진 주파수 분석법에 의한 임플랜트의 안정성 측정에 관한 연구)

  • Park Cheol;Lim Ju-Hwan;Cho In-Ho;Lim Heon-Song
    • The Journal of Korean Academy of Prosthodontics
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    • v.41 no.2
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    • pp.182-206
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    • 2003
  • Statement of problem : Successful osseointegration of endosseous threaded implants is dependent on many factors. These may include the surface characteristics and gross geometry of implants, the quality and quantity of bone where implants are placed, and the magnitude and direction of stress in functional occlusion. Therefore clinical quantitative measurement of primary stability at placement and functional state of implant may play a role in prediction of possible clinical symptoms and the renovation of implant geometry, types and surface characteristic according to each patients conditions. Ultimately, it may increase success rate of implants. Purpose : Many available non-invasive techniques used for the clinical measurement of implant stability and osseointegration include percussion, radiography, the $Periotest^{(R)}$, Dental Fine $Tester^{(R)}$ and so on. There is, however, relatively little research undertaken to standardize quantitative measurement of stability of implant and osseointegration due to the various clinical applications performed by each individual operator. Therefore, in order to develop non-invasive experimental method to measure stability of implant quantitatively, the resonance frequency analyzer to measure the natural frequency of specific substance was developed in the procedure of this study. Material & method : To test the stability of the resonance frequency analyzer developed in this study, following methods and materials were used : 1) In-vitro study: the implant was placed in both epoxy resin of which physical properties are similar to the bone stiffness of human and fresh cow rib bone specimen. Then the resonance frequency values of them were measured and analyzed. In an attempt to test the reliability of the data gathered with the resonance frequency analyzer, comparative analysis with the data from the Periotest was conducted. 2) In-vivo study: the implants were inserted into the tibiae of 10 New Zealand rabbits and the resonance frequency value of them with connected abutments at healing time are measured immediately after insertion and gauged every 4 weeks for 16 weeks. Results : Results from these studies were such as follows : The same length implants placed in Hot Melt showed the repetitive resonance frequency values. As the length of abutment increased, the resonance frequency value changed significantly (p<0.01). As the thickness of transducer increased in order of 0.5, 1.0 and 2.0 mm, the resonance frequency value significantly increased (p<0.05). The implants placed in PL-2 and epoxy resin with different exposure degree resulted in the increase of resonance frequency value as the exposure degree of implants and the length of abutment decreased. In comparative experiment based on physical properties, as the thickness of transducer increased, the resonance frequency value increased significantly(p<0.01). As the stiffness of substances where implants were placed increased, and the effective length of implants decreased, the resonance frequencies value increased significantly (p<0.05). In the experiment with cow rib bone specimen, the increase of the length of abutment resulted in significant difference between the results from resonance frequency analyzer and the $Periotest^{(R)}$. There was no difference with significant meaning in the comparison based on the direction of measurement between the resonance frequency value and the $Periotest^{(R)}$ value (p<0.05). In-vivo experiment resulted in repetitive patternes of resonance frequency. As the time elapsed, the resonance frequency value increased significantly with the exception of 4th and 8th week (p<0.05). Conclusion : The development of resonance frequency analyzer is an attempt to standardize the quantitative measurement of stability of implant and osseointegration and compensate for the reliability of data from other non-invasive measuring devices It is considered that further research is needed to improve the efficiency of clinical application of resonance frequency analyzer. In addition, further investigation is warranted on the standardized quantitative analysis of the stability of implant.

Species-specific Expression of Rpia Transcript in Cumulus-oocyte-complex (난자-난구세포 복합체에서 발현하는 Rpia 유전자의 종 특이적 발현)

  • Kim, Yun-Sun;Yoon, Se-Jin;Kim, Eun-Young;Lee, Kyung-Ah
    • Clinical and Experimental Reproductive Medicine
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    • v.34 no.2
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    • pp.95-106
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    • 2007
  • Objective: We previously identified differentially expressed genes (DEGs) between germinal vesicle (GV) and metaphase II (MII) mouse oocyte. The present study was accomplished as a preliminary study to elucidate the role of ribose 5-phosphate isomerase A (Rpia), the essential enzyme of the pentose phosphate pathway (PPP), in oocyte maturation. We observed expression of Rpia in the mouse and porcine oocytes. Methods: Expression pattern of the 11 MII-selective DEGs in various tissues was evaluated using RT-PCR and selected 4 genes highly expressed in the ovary. According to the oocyte-selective expression profile, we selected Rpia as a target for this study. We identified the porcine Rpia sequence using EST clustering technique, since it is not yet registered in public databases. Results: The extended porcine Rpia nucleotide sequence was submitted and registered to GenBank (accession number EF213106). We prepared primers for porcine Rpia according to this sequence. In contrast to the oocyte-specific expression in the mouse, Rpia was expressed in porcine cumulus and granulosa cells as well as in oocytes. Conclusion: This is the first report on the characterization of the Rpia gene in the mouse and porcine ovarian cells. Results of the present study suggest that the mouse and porcine COCs employ different mechanism of glucose metabolism. Therefore, the different metabolic pathways during in vitro oocyte maturation (IVM) in different species may lead different maturation rates. It is required to study further regarding the role of Rpia in glucose metabolism of oocytes and follicular cell fore exploring the regulatory mechanism of oocyte maturation as well as for finding the finest culture conditions for in vitro maturation.

A Three-year Study on the Leaf and Soil Nitrogen Contents Influenced by Irrigation Frequency, Clipping Return or Removal and Nitrogen Rate in a Creeping Bentgrass Fairway (크리핑 벤트그라스 훼어웨이에서 관수회수.예지물과 질소시비수준이 엽조직 및 토양 질소함유량에 미치는 효과)

  • 김경남;로버트쉬어만
    • Asian Journal of Turfgrass Science
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    • v.11 no.2
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    • pp.105-115
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    • 1997
  • Responses of 'Penncross' creeping bentgrass turf to various fairway cultural practices are not well-established or supported by research results. This study was initiated to evaluate the effects of irrigation frequency, clipping return or removal, and nitrogen rate on leaf and soil nitrogen con-tent in the 'Penncross' creeping bentgrass (Agrostis palustris Huds.) turf. A 'Penncross' creeping bentgrass turf was established in 1988 on a Sharpsburg silty-clay loam (Typic Argiudoll). The experiment was conducted from 1989 to 1991 under nontraffic conditions. A split-split-plot experimental design was used. Daily or biweekly irrigation, clipping return or removal, and 5, 15, or 25 g N $m-^2$ $yr-^1$ were the main-, sub-, and sub-sub-plot treatments, respectively. Treatments were replicated 3 times in a randomized complete block design. The turf was mowed 4 times weekly at a l3 mm height of cut. Leaf tissue nitrogen content was analyzed twice in 1989 and three times in both 1990 and 1991. Leaf samples were collected from turfgrass plants in the treatment plots, dried immediately at 70˚C for 48 hours, and evaluated for total-N content, using the Kjeldahl method. Concurrently, six soil cores (18mm diam. by 200 mm depth) were collected, air dried, and analyzed for total-N content. Nitrogen analysis on the soil and leaf samples were made in the Soil and Plant Analyical Laboratory, at the University of Nebraska, Lincoln, USA. Data were analyzed as a split-split-plot with analysis of variance (ANOVA), using the General Linear Model procedures of the Statistical Analysis System. The nitrogen content of the leaf tissue is variable in creeping bentgrass fairway turf with clip-ping recycles, nitrogen application rate and time after establishment. Leaf tissue nitrogen content increased with clipping return and nitrogen rate. Plots treated with clipping return had 8% and 5% more nitrogen content in the leaf tissue in 1989 and 1990, respectively, as compared to plots treated with clipping removal. Plots applied with high-N level (25g N $m-^2$ $yr-^1$)had 10%, 17%, and 13% more nitrogen content in leaf tissue in 1989, 1990, and 1991, respectively, when compared with plots applied with low-N level (5g N $m-^2$ $yr-^1$). Overall observations during the study indicated that leaf tissue nitrogen content increased at any nitrogen rate with time after establishment. At the low-N level treatment (5g N $m-^2$ $yr-^1$ ), plots sampled in 1991 had 15% more leaf nitrogen content, as compared to plots sampled in 1989. Similar responses were also found from the high-N level treatment (25g N $m-^2$ $yr-^1$ ).Plots analyzed in 1991 were 18% higher than that of plots analyzed in 1989. No significant treatment effects were observed for soil nitrogen content over the first 3 years after establishment. Strategic management application is necessary for the golf course turf, depending on whether clippings return or not. Different approaches should be addressed to turf fertilization program from a standpoint of clipping recycles. It is recommended that regular analysis of the soil and leaf tissue of golf course turf must be made and fertilization program should be developed through the interpretation of its analytic data result. In golf courses where clippings are recycled, the fertilization program need to be adjusted, being 20% to 30% less nitrogen input over the clipping-removed areas. Key words: Agrostis palustris Huds., 'Penncross' creeping bentgrass fairway, Irrigation frequency, Clipping return, Nitrogen rate, Leaf nitrogen content, Soil nitrogen content.

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Determination of cross section of composite breakwaters with multiple failure modes and system reliability analysis (다중 파괴모드에 의한 혼성제 케이슨의 단면 산정 및 제체에 대한 시스템 신뢰성 해석)

  • Lee, Cheol-Eung;Kim, Sang-Ug;Park, Dong-Heon
    • Journal of Korea Water Resources Association
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    • v.51 no.9
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    • pp.827-837
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    • 2018
  • The stabilities of sliding and overturning of caisson and bearing capacity of mound against eccentric and inclined loads, which possibly happen to a composite caisson breakwaters, have been analyzed by using the technique of multiple failure modes. In deterministic approach, mathematical functions have been first derived from the ultimate limit state equations. Using those functions, the minimum cross section of caisson can straightforwardly be evaluated. By taking a look into some various deterministic analyses, it has been found that the conflict between failure modes can be occurred, such that the stability of bearing capacity of mound decreased as the stability of sliding increased. Therefore, the multiple failure modes for the composite caisson breakwaters should be taken into account simultaneously even in the process of deterministically evaluating the design cross section of caisson. Meanwhile, the reliability analyses on multiple failure modes have been implemented to the cross section determined by the sliding failure mode. It has been shown that the system failure probabilities of the composite breakwater are very behaved differently according to the variation of incident waves. The failure probabilities of system tend also to increase as the crest freeboards of caisson are heightening. The similar behaviors are taken place in cases that the water depths above mound are deepening. Finally, the results of the first-order modal are quite coincided with those of the second-order modal in all conditions of numerical tests performed in this paper. However, the second-order modal have had higher accuracy than the first-order modal. This is mainly due to that some correlations between failure modes can be properly incorporated in the second-order modal. Nevertheless, the first-order modal can also be easily used only when one of failure probabilities among multiple failure modes is extremely larger than others.

Changes in Characteristics of Brown Rice (Goami) Alcohol Fermentation By-Product by Cellulase (Cellulase처리에 따른 현미(고아미) 알코올발효 부산물의 특성 변화)

  • Woo, Seung-Mi;Jang, Se-Young;Park, Nan-Yong;Kim, Tae-Young;Yeo, Soo-Hwan;Kim, Sang-Burm;Jeong, Yong-Jin
    • Food Science and Preservation
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    • v.15 no.1
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    • pp.99-104
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    • 2008
  • To utilize non-heat treated alcoholic by-products of brown rice (Goami) as food sources, the quality characteristics changes according to the treatment conditions of cellulase were evaluated. Results showed that the increase of hydrolysis temperature correspondingly increased the soluble solids and total sugar amounts in the by-products of Goami, and total dietary fiber amount was found to be around 0.67% Reducing sugar concentration was the highest at the hydrolysis temperature of $70^{\circ}C$. Maltooligosaccharides amounts were detected to be the highest at the hydrolysis temperature of $80^{\circ}C$ and were also, maltopentose and maltopentose were found. In the soluble solid, total dietary fiber, reducing sugar and total sugar according to the cellulase concentration, the content of hydrolysates with enzyme were higher than control, and the content of hydrolysates with enzyme was similar (6.30 and 0.69% 3,600 and 5,500 mg% respectively). The content of maltooligosaccharides was increased with the increase of enzyme concentration, and the content was similar at more than 0.6%(w/w) of enzyme concentration. The soluble solids and total dietary fiber by hydrolysis time were found to be 6.25% and 0.70%, respectively at more than 60 min. of hydrolysis. The content of reducing sugar, total sugar and maltooligosaccharides were increased with the increase of hydrolysis time, and the content was similar at more than 120min. of hydrolysis (3,800, 5,680 and 1,950 mg% respectively). Based upon these results, the byproducts of Goami are expected to be valuable as various food sources showing the highest dietary fiber and maltooligosaccharides contents by the hydrolysis at $80^{\circ}C$ for 120 min. with the addition of 0.6%(w/w) of cellulase.

Quality characteristics of fermented vinegar prepared with the detoxified Rhus verniciflua extract (무독화 옻 추출물로 제조한 발효식초의 품질 특성)

  • Baek, Seong Yeol;Lee, Choong Hwan;Park, Yoo Kyoung;Choi, Han-Seok;Mun, Ji-Young;Yeo, Soo-Hwan
    • Food Science and Preservation
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    • v.22 no.5
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    • pp.674-682
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    • 2015
  • In this study, vinegar was produced using urushiol-free fermented Rhus verniciflua extract to create a lacquer with added value. The effect of manufacturing conditions on the quality of vinegar using detoxified R. verniciflua extract for fermentation was investigated. The acidity of the vinegar for inoculations with various liquid starter contents was 4.8~4.9%, and it was similar among all treatment groups. The acidity of vinegar was higher when the initial alcohol content was high. The acetic acid yields were 82.8%, 84.4%, 77.7%, and 69.5%, and the maximum yield was observed when the initial alcohol content was 6%. For acetic acid fermentation using different amounts of detoxified R. verniciflua extracts, the acidity of the vinegar with the extract after fermentation was 5.3~5.9%. However, the acidity of vinegar without the extract was 5.5%. The intensity of the brown color was high for vinegar without the extract. Hunter's L values were high for vinegar with an extract content of 2%. Acetic acid (53.3~65.8 mg/mL) was the predominant acid. Arginine ($190.3{\sim}333.3{\mu}g/mL$), proline ($125.6{\sim}290.8{\mu}g/mL$), alanine ($126.1{\sim}270.9{\mu}g/mL$), and glutamic acid ($159.0{\sim}262.4{\mu}g/mL$) were the predominant amino acids in detoxified R. verniciflua vinegar.