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The Dyeing Properties of Woody Fiber Regenerated from Waste MDF by Reactive Dyes (반응성염료에 의한 폐MDF 재생 목질섬유의 염색특성)

  • Ju, Seon-Gyeong;Roh, JeongKwan
    • Journal of the Korean Wood Science and Technology
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    • v.47 no.2
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    • pp.163-177
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    • 2019
  • This study aims to review the relations between the dyeing conditions (i.e., dye concentration, addition amounts of salt and alkali, and dyeing temperature) and dyeing properties and color fastness to light for identifying the optimal dyeing conditions when dyed regenerated woody fibers were obtained through the defibration of waste medium density fiberboard (MDF) using reactive Red H-E3B (Bis-monochlorotriazine (MCT)/MCT type) and reactive Red RB133% (Bis-MCT/Vinyl sulphone type). The dyeing yield (K/S) obtained using two types of reactive dyes increased as the dye concentration increased by 1-10% (on the weight of fiber (OWF)). In addition, the K/S of H-E3B was higher than that of RB133% irrespective of the dye concentration. The color difference of H-E3B after ultraviolet (UV) radiation was lower than that of RB133%, denoting good resistance to discoloration by UV. As the amount of sodium sulfate increased, the color difference and K/S also increased, and the adequate salt content was determined to be 50-70 g/L. Further, the color difference and K/S significantly increased only the addition of 2 g/L of sodium carbonate; however, almost no difference was observed when more than 2 g/L of sodium carbonate was added. The addition amount of sodium carbonate was adequate 5-10 g/L to dyeing the fiber and the pH at this addition level was 10. The dyeing yield of H-E3B increased when the dyeing temperature increased; however, it subsequently decreased after the dyeing temperature became $80^{\circ}C$. The dyeing yield of RB133% was almost the same up to $60-70^{\circ}C$ but declined subsequently. Thus, the adequate temperatures were $80^{\circ}C$ and $60^{\circ}C$ for H-E3B and RB133%, respectively. If the waste MDF woody fiber was dyed under the aforementioned optimal conditions, dyed regenerated woody fiber can be obtained having the following colors: 1.5 to 2.0R with the H-E3B dye and 9.6 to 10.0 PR with RB133%.

Deterioration Evaluation Method of Noise Barriers for Managements of Highway (고속도로 방음벽 유지관리를 위한 방음벽 노후도 평가 방안)

  • Kim, Sangtae;Shin, Ilhyoung;Kim, Kyoungsu;Kim, Daae;Kim, Heungrae;Im, Jahae;Lee, Jajun
    • Journal of Environmental Impact Assessment
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    • v.28 no.4
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    • pp.387-399
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    • 2019
  • This research aimed to prepare the classification of the damage types and the damage rating system of noise barriers for expressway noise barriers and to develop deterioration evaluation method of noise barriers by reflecting them. The noise barrier consists of soundproof panels, foundations and posts and the soundproof panels with 10 different types of materials are used in a single or mixed form.In this paper, damage of soundproof panel shows a single or composite damage, and thus a evaluation model of deterioration has been developed for noise barriers that can reflect the characteristic of noise barriers. Materials used mainly for soundproof walls were divided into material types for metal, plastic, timber, transparent and concrete. And damage types for noise barrier were classified into corrosion, discoloration, deformation, spalling and dislocation and damage types were subdivided according to the noise barrier's components and materials. Damage rating was divided into good, minor, normal and severe for each major part of noise barrier to assess damage rating of soundproof panel, foundation and post. The deterioration degree of noise barrier was evaluated comprehensively by using the deterioration evaluation method of whole noise barrier using weighted average. Deterioration evaluation method that can be systematically assessed has been developed for noise barrier using single or mixed soundproof panel and noise barrier with single or complex damage types. Through such an evaluation system, it is deemed that the deterioration status of noise barrier installed can be systematically understood and utilized for efficient maintenance planning and implementation for repair and improvement of noise barriers.

Effect of polishing methods on color change by water absorption in several composite resins (여러 복합레진에서 수분 흡수에 의한 색변화에 연마가 미치는 영향)

  • Kim, Hye Jin;Kim, Mi-yeon;Song, Byung-chul;Kim, Sun-ho;Kim, Jeong-hee
    • Journal of Dental Rehabilitation and Applied Science
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    • v.35 no.1
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    • pp.1-10
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    • 2019
  • Purpose: The aim of this study was to evaluate the influence of polishing methods on the color stability of composite resins. Materials and Methods: Two bulk-fill and four conventional resin composites were filled in cylindrical molds (6 mm diameter, 4 mm height) and light-cured. The specimens were stored in $34^{\circ}C$ distilled water for 24 h. Spectrophotometer was used to determine the color value according to the CIE $L^*a^*b^*$ color space. Each group was divided into three groups according to polishing methods (n = 5). Group 1 was control group (Mylar strip group), group 2 was polished with PoGo, and group 3 was polished with Sof-Lex Spiral wheels. Color evaluation was performed weekly for 4 weeks after immersion in $34^{\circ}C$ distilled water. The results were analyzed by generalized least squares method (P < 0.05). Results: Generalized least squares analysis revealed that Sof-Lex Spiral wheels group showed the significantly lower ${\Delta}E$ values compared to PoGo and control group (P < 0.05). The ${\Delta}E$ values of polished group showed the significantly lower than the ${\Delta}E$ values of unpolished group (P < 0.05). Regarding color changes of composite resins, there was no significant difference between the ${\Delta}E$ values of Filtek Z250 and Filtek Z350 XT Universal restorative in all time intervals (P < 0.05). Tetric N-Ceram Bulk Fill showed the significantly lower ${\Delta}E$ values compared to other composite resins in 1, 2, 3 weeks (P < 0.05). Conclusion: Within the limitations of this study, polishing methods influence the color stabilities of composite resins. The group polished with Sof-Lex Spiral Wheels showed more resistance to discoloration than group polished with PoGo.

Spectral Band Selection for Detecting Fire Blight Disease in Pear Trees by Narrowband Hyperspectral Imagery (초분광 이미지를 이용한 배나무 화상병에 대한 최적 분광 밴드 선정)

  • Kang, Ye-Seong;Park, Jun-Woo;Jang, Si-Hyeong;Song, Hye-Young;Kang, Kyung-Suk;Ryu, Chan-Seok;Kim, Seong-Heon;Jun, Sae-Rom;Kang, Tae-Hwan;Kim, Gul-Hwan
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.23 no.1
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    • pp.15-33
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    • 2021
  • In this study, the possibility of discriminating Fire blight (FB) infection tested using the hyperspectral imagery. The reflectance of healthy and infected leaves and branches was acquired with 5 nm of full width at high maximum (FWHM) and then it was standardized to 10 nm, 25 nm, 50 nm, and 80 nm of FWHM. The standardized samples were divided into training and test sets at ratios of 7:3, 5:5 and 3:7 to find the optimal bands of FWHM by the decision tree analysis. Classification accuracy was evaluated using overall accuracy (OA) and kappa coefficient (KC). The hyperspectral reflectance of infected leaves and branches was significantly lower than those of healthy green, red-edge (RE) and near infrared (NIR) regions. The bands selected for the first node were generally 750 and 800 nm; these were used to identify the infection of leaves and branches, respectively. The accuracy of the classifier was higher in the 7:3 ratio. Four bands with 50 nm of FWHM (450, 650, 750, and 950 nm) might be reasonable because the difference in the recalculated accuracy between 8 bands with 10 nm of FWHM (440, 580, 640, 660, 680, 710, 730, and 740 nm) and 4 bands was only 1.8% for OA and 4.1% for KC, respectively. Finally, adding two bands (550 nm and 800 nm with 25 nm of FWHM) in four bands with 50 nm of FWHM have been proposed to improve the usability of multispectral image sensors with performing various roles in agriculture as well as detecting FB with other combinations of spectral bands.

Initial cooling conditions that extend the shelf-life of fresh oak mushrooms (Lentinula edodes) after harvest (신선 표고의 수확 후 유통수명 연장을 위한 예냉조건 구명)

  • Choi, Ji Weon;Lee, Ji Hyun;Kim, Chang-Kug;Park, Me Hea;Choi, Hyun jin;Lim, Sooyeon;Eum, Hyang Lan;Chang, Min-Sun;Hong, Yoon Pyo
    • Journal of Mushroom
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    • v.20 no.3
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    • pp.138-146
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    • 2022
  • To optimize initial cooling conditions, forced-air cooling was applied to freshly harvested oak mushrooms at 2 levels (0℃ for 30 minutes, at 0℃ for 1 hour) followed by room cooling at 3 levels (-3℃ for 1 day, 0℃ for 1 day, 3℃ for 1 day). After initial cooling, the oak mushrooms were packaged with PVC film, then held in a storage room at 1℃ for 6 weeks. Quality characteristics and percentage marketability were then investigated. As a control, Mushrooms were placed in storage with no initial cooling. The quality factors impacting marketability of fresh oak mushrooms were color change and appearance of decay. Off-odor did not occur or developed only slightly, so it did not affect oak mushroom quality within 6 weeks of low temperature storage. In all treatment groups, the shelf life in which 100% marketability was maintained was up to 3 weeks. At week 5, percent marketability of the 3 treatment groups 1 hour room cooling treatment at 0℃, 1 hour forced air cooling, and control was 100%. 80% In the group that underwent 30 min forced air cooling retained 80% marketability, and the group exposed to 1 day in room cooling at -3℃ retained 86.7% marketability. At week 6 of 1℃ storage, the marketability ratio was 80% in the 1 day room cooling at 0℃ group, 66.7% in the 1 day room cooling at 3℃ group, 46.7% in the 1 hour forced air cooling group, and 33% or less in all other treatment groups. Therefore, the most suitable initial cooling parameter to extend shelf-life of oak mushrooms is 1 day of in room cooling at 0℃ immediately after harvest.

Grapevine Growth and Berry Development under the Agrivoltaic Solar Panels in the Vineyards (영농형 태양광 시설 설치에 따른 포도나무 생육 및 과실 특성 변화 비교)

  • Ahn, Soon Young;Lee, Dan Bi;Lee, Hae In;Myint, Zar Le;Min, Sang Yoon;Kim, Bo Myung;Oh, Wook;Jung, Jae Hak;Yun, Hae Keun
    • Journal of Bio-Environment Control
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    • v.31 no.4
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    • pp.356-365
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    • 2022
  • Agrivoltaic systems, also called solar sharing, stated from an idea that utilizes sunlight above the light saturation point of crops for power generation using solar panels. The agrivoltaic systems are expected to reduce the incident solar radiation, the consequent surface cooling effect, and evapotranspiration, and bring additional income to farms through solar power generation by combining crops with solar photovoltaics. In this study, to evaluate if agrivoltaic systems are suitable for viticulture, we investigated the microclimatic change, the growth of vines and the characteristics of grape grown under solar panels set by planting lines compared with ones in open vineyards. There was high reduction of wind speed during over-wintering season, and low soil temperature under solar panel compared to those in the open field. There was not significant difference in total carbohydrates and bud burst in bearing mother branches between plots. Despite high content of chlorophyll in vines grown under panels, there is no significant difference in shoot growth of vines, berry weight, cluster weight, total soluble solid content and acidity of berries, and anthocyanin content of berry skins in harvested grapes in vineyards under panels and open vineyards. It was observed that harvesting season was delayed by 7-10 days due to late skin coloration in grapes grown in vineyards under panels compared to ones grown in open vineyards. The results from this study would be used as data required in development of viticulture system under panel in the future and further study for evaluating the influence of agrivoltaic system on production of crops including grapes.

Color Distribution of Maxillary Permanent Incisors in Korean Pediatric Patients Using a Spectrophotometer (분광광도계를 이용한 한국 소아 환자의 상악 영구 절치 색조 분석)

  • Seunghyun, Oh;Hyuntae, Kim;Teo Jeon, Shin;Hong-Keun, Hyun;Young-Jae, Kim;Jung-Wook, Kim;Ki-Taeg, Jang;Ji-Soo, Song
    • Journal of the korean academy of Pediatric Dentistry
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    • v.49 no.4
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    • pp.414-427
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    • 2022
  • This study aims to analyze the color distribution of maxillary permanent incisors in Korean pediatric patients and determine the effects of age and root developmental stage on tooth color. The L*a*b* values of 404 sound and fully erupted maxillary incisors without dental caries, restorations, trauma history or discoloration from 101 Korean patients between ages 7 and 15, with a mean age 10.0 ± 1.5, were analyzed with a spectrophotometer. CIE L*a*b* values were 84.01, 0.17, and 24.07 in maxillary central incisors, and 82.33, 0.31, and 25.99 in maxillary lateral incisors. L* values of maxillary central incisors were higher, and b* values of maxillary central incisors were lower than those of maxillary lateral incisors (p < 0.001). The color differences among the subregions exceeded the clinical perceptibility threshold in both of the maxillary central and lateral incisors. L* value for children at age 10 and younger was 84.13 in maxillary central incisors and 84.04 in maxillary lateral incisors, and those of older patients were 80.62 and 80.56, respectively. L* value of maxillary incisors of children at age 10 and younger was significantly higher than that of older patients. The root developmental stage did not affect tooth color. This study suggests that the color differences between maxillary central and lateral incisors and among the subregions of a tooth and the effects of age should be considered for aesthetic restorations of permanent incisors in pediatric patients.

Scientific Analysis and Conservation Treatment on the Buddhist Scriptures of Paper Relics Excavated from Sum Tolgoi, Mongolia (몽골 숨 톨고이 출토 지류 유물의 과학적 분석 및 보존처리)

  • Bae, Su Bin;Yang, Min Jeong;Kwon, Yun Mi;Yoo, Ji Hyun;Jeong, Hee Won
    • Journal of Conservation Science
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    • v.37 no.6
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    • pp.723-737
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    • 2021
  • This study analyzed the composition and structure of materials with Buddhist paper scriptures excavated from architectural sites in 'Sum Tolgoi' of the 17th century and carried out conservation treatment base on the result of the analysis. The scriptures were covered in dust and foreign sub stances, and were so crumpled that it was impossible to identify the form. The damage, loss, and discoloration have been identified. Buddhist scriptures written in Tibetan used indigo and ink sticks on paper as a result of UV-Vis analysis, and ink sticks as black character materials from scriptures written ancient Mongolian. SEM-EDS and Micro-XRF analyses revealed that the outlines were drawn with red lines using a mix of Minium (Pb3O4) and Cinnabar (HgS), or Cinnabar (HgS) alone, and the contents of the scriptures were written with silver paint. Silver chloride (AgCl) and Calcium (Ca) were identified in the silver paint component of the characters, while Calcium and Orpiment (As2S3) were identified in the yellow lines. Concerning the paper ground, Buddhist scriptures written in ancient Mongolian were characterized by herbal plant fiber and bast fiber, and those written in Tibetan, by bast fiber. Radiocarbon dating indicates that the paper for the scriptures was produced between the 15th and 17th centuries. Conservation treatment of the scriptures was carried out based on the experiment on the production of pre-coated paper and how to coat that to prevent the second damage due to the deformation and fragility of the excavated paper. The scriptures were preserved and mounted, and a neutral box was made to identify the contents of the scriptures recorded on both sides after the treatment. This conservation treatment is the result of a study that applied new conservation treatment materials and methods according to the principle of conservation treatment reversibility.

Ecological Study on Poisonous Snake and Investigation of the Venom Characteristics, Snakebiting Frequenty in Korea (한국산 독사의 생태학적 특징 및 독성, 교상빈도에 관한 조사, 연구)

  • Shim, Jae-Han;Son, Young-Jong;Lee, Sang-Seob;Park, Kyung-Seok;Oh, Hee-Bok;Park, Young-Do
    • Korean Journal of Environment and Ecology
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    • v.12 no.1
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    • pp.58-77
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    • 1998
  • Four species(25%) of Viperidae(Agkistrodon brevicaudus, Agkistrodon ussuriensis, Agkistrodon saxatilis) and Cloubridae(Rhabdophis tigrenus tigrenus) were Korean poisonous snake. Copulation season of these species was from July to August. Reproduction mode of genus Agkistrodon species was ovoviviparous but Rhabdophis tigrinus tigrinus was the other pattern of oviparous. Optimal movement temperature range was from 20$\circ $C to 29$\circ $C(March~September). Wjen atmosphere temperature was below 10$\circ $C, at that time they hibernate at the ground, rock bottom, stone wall and embankment around the end of a field. The venom of these snakes consist mainly Hematoxin, Cytolysin, Neurotoxin and Cardiotoxin of poisonous liquids. These material injection to animal cause systemic syndrome such as Dizziness(25.7%), Vomitting(23.1%), Fever(22%), Visual trouble(18%), Headace(17.7%), Dyspnoea(17.6%) and bring about other local syndrome such as Discoloration(54.2%), Bleeding(20.2%), Bullae(10.7%) and Skin ulcer(!0.8%). The annual distribution was appeared to decrease 1972 after 1992 and average snakebiting patients was 25.6 per year, but practically total estimated snakebiting was 2,700 per year. The seasonal distribution was most frequent in August(25%), and mortality was 1.8%(26 per 1,430). The sex ratio was 2:1 and according to age distribution, it was most prevalent at one's fifties(19%). The most frequent place where the accident happened was the field(48.2%) and most predilection site of the body for victim were hand(47.8%) and foot(39.5%), Commonly bite snake were Agkistrodon ussuriensis(27.1%), Agkistrodon brevicaudus(22.6%) and Agkistrodon saxatilis(9.6%) but 40.7% of species could not be identified. Treatment of antivenin patient was 75.9% (1,068/1,407).

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Studies on the Chilling Injury of Rice Seedlings III. Possibility of Low-Temperature Hardening (수도의 유묘기 냉해에 관한 연구 III. 유묘의 저온경화 가능성 검토)

  • Kwon, Y.W.;Ahn, M.B.;Oh, Y.J.
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.24 no.3
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    • pp.21-25
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    • 1979
  • To evaluate the possibility of hardening of rice seedlings to chilling injury by low temperature conditioning for improvement of nursery temperature management a chilling sensitive new variety Tongil from Indica \times Japonica cross and a chilling tolerant Japonica variety Jinheung were reared by the 3rd leaf-stage in a day $30^{\circ}C/night\; 20^{\circ}C$ growth chamber, and were subjected to temperature conditioning for hardening against chilling injury for 6 days. Then the seedlings conditioned and unconditioned were chilled in a day and night $8^{\circ}C$ chamber for 2, 4, 6, or 8 days long and returned to the day and night $30^{\circ}C/night\; 20^{\circ}C$ condition for development of chilling injuries. Survival rate after chilling injury development of the variety Tongil showed distinct effect of hardening, i. e. the unhardened-25 % survival, the hardened by a gradual drop of temperature regime $(30^{\circ}C/20^{\circ}C\rightarrow24^{\circ}C/14^{\circ}C\rightarrow18^{\circ}C/12^{\circ}C\rightarrow8^{\circ}C)4 -59% survival and the hardened. by repeated brief exposure (4hrs. to 6hrs.) to $8^{\circ}C$ shock-89% survival against chilling of $8^{\circ}C$ for 4 days long. The variety Jinheung survived even against 8 days chilling at $8^{\circ}C$ C, but the discoloration rate of leaves due to chilling showed noticeably the hardening effect as repeated shock was much better than the gradually lowering temperatures.

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