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        검색결과 28

        5.
        2018.05 구독 인증기관·개인회원 무료
        In this paper, first the aging level of Stone Mastic Asphalt (SMA): one of the widely applied asphalt mixture types for highway construction in South Korea, was analysed then those aging effects on various performance characteristics were studied. Then, a suitable methodology for improving performance on real asphalt pavement construction site was recommended. To fulfil the objective, Gel-Permeation Chromatography (GPC) experimental work was performed on various aged SMA mixtures by measuring Large Molecular Size (LMS) then the Absolute Viscosity (AV) value was predicted based on the findings in the previous step. As results, it was found that types of performance change on aged asphalt binders could be estimated by computed Estimated Absolute Viscosity (EAV) values. It also should be mentioned that the performances of tested SMA mixture presented negative trend after aging effect increases; even though the performance deterioration level of SMA is lower than that of regular Dense Grade Asphalt (DGA) mixture, which means proper reactions are recommended to keep its quality. Moreover, better resistance against aging effect was found by applying Hydrated-Lime (HL) or Low Density Poly-Ethylene (LDPE) compared to any other additives on asphalt mixtures. A unique Aging Quantity (AQ) model for SMA mixtures was developed by using two factors: collected aging time data set from field (and/or laboratory) and AV values based on different temperature conditions. The Predicted Absolute Viscosity (PAV) on SMA mixtures was computed by using the introduced AQ model then the aging level of asphalt binder was estimated as a final step. Additionally, five performance characteristics of asphalt binder: Dynamic Shear Rheometer(DSR) high temperature limit, Bending Beam Rheometer (BBR) low temperature limit, G*/sinδ, Creep stiffness, and m-value, were analysed. The value of AV showed the best performance for predicting and representing aging level. Finally, the aging level of given asphalt mixtures in the field can be easily predicted by choosing one of three approaches presented in this research. It can be concluded that the performance of asphalt pavement can be increased by selecting proper materials and performance prediction methodologies introduced in this study. However, only limited number of specimens were considered in this study due to limit of raw materials and laboratory equipment condition. Therefore, extensive experimental works with various types of asphalt materials are recommended for strengthen findings in this thesis as a future research.
        6.
        2018.05 구독 인증기관·개인회원 무료
        The Semi-Rigid Pavement (SRP) mixture is composed of Gap Graded Asphalt (GGA) mixture (air void = 20~28%) and cement paste. By inserting cement paste into voids in GGA mixture, SRP can provide not only flexibility but also rigidity characteristics on pavement performance. SRP can mitigate pavement surface temperature increase during summer session, provide better smoothness and mitigate rutting distress due to heavy weight vehicles, successfully. In Japan, SRP is widely applied in cross section area, heavy vehicle parking lot and highway ticketing booth in highway network system. In South Korea, SRP was introduced and applied since 2005. However, still more researches and studies are needed to understand material characteristics and improve performance of SRP. Moreover, the current SRP system in South Korea merely follows and adapts the aggregate gradation information from Japan which needs to be amended and customized into original material (i.e. aggregate, binder and cement) situation of South Korea. In this paper, SRP system based on Stone Mastic Asphalt (SMA) mixture design originated from Korea Expressway Corporation (KEC) and enhanced cement paste with addition of fly-ash and slags was developed. In addition, an optimized proportion between asphalt mixture air voids and cement paste amount with consideration of economic benefit was introduced. Based on field evaluation process it can be said that the newly developed SRP system can successfully adapted not only in static site on highway: parking lots or ticketing booth, but also in dynamic site on highway: driving and wheel path.
        7.
        2018.05 구독 인증기관·개인회원 무료
        The composition of the deicer sprayed on the highway is spreading over the highway by the scattering or snow removal activity, or car movement and consequently affecting the vegetation environment around the highway. These are the cause of the damage of fruit trees and crops, and also the cause of corrosion of highway structures. The goal of this study is to estimate the detected range of deicer components from a highway. The concentration of the deicer components in gauze and soil were investigated according to the crossing distance from the highway. The data collected were then used to estimate the concentration range of deicer components in a rage of distance up to 100 m from the highway where the deicer was spread. The sample time and weight of gauze were measured before and after installation, and the soil was collected at more than three points in parallel with the highway at the gauze installation point. The components in gauze and soil were investigated in addition to the deicer components (Ca2+, Na+, Cl-) as well as Mg2+ and K+. As Ca2+ and Cl- components of deicer were affected by agricultural use, Na+ component was selected as a tracer and further SAR (Sodium Adsorption Ratio) of soil was analyzed to examine the degree of influence on vegetation indirectly. The gauze concentration was evaluated by the concentration of the deicer ingredient at the background concentration of the blank gauze. The total amount of the deicer sprayed in the study road for 4 months (winter season) was about 93 ton/km. In the gauze test, the spread of the deicer was detected at a distance of 100 m in study area, but the concentration of the deicer in the gauze by distance decreased rapidly within 10 m from the highway. And concentration of the deicer components in gauze and soil came down after rainy season (August ~ Sep.). The results showed that the components of the deicer could be spread widely by the wind. The effective range of the deicer on vegetation based on SAR in soil was estimated to be less than 20 m from the highway. This study examines the concentration changes of the deicer components in gauze and soils and shows that deicer components sprayed on the highway are accumulated and moved over time by wind, snow removal, terrain, water system and land use around the highway.
        8.
        2018.05 구독 인증기관·개인회원 무료
        Some of the deicer ingredients are the same as fertilizer ingredients from agricultural activities. The goal of this study is to distinguish the components of highway deicer from the components used for agriculture. Among the deicer ingredients, Ca and Cl are substances which can be supplied by fertilizer or livestock manure. However, fertilizer and livestock manure contain plenty of nitrogen, organic matter, phosphoric acid and magnesium, including deicer ingredients. The soil physico-chemical characteristics were analyzed according to the distance from the highway. The physico-chemical analysis items of the soil include electrical conductivity, total nitrogen (TN), available phosphate (Av.P), organic matter (OM), ammonia nitrogen (NH4-N), Cation Exchange Capacity (CEC). In the case of effective phosphoric acid, leaching into the subsoil is very low due to various binding mechanisms in the soil. However, it is considered that the compost (fertilizer) applied to the topsoil is mixed with the soil by the tillage or flattening operation. In addition to the organic matter content of the subsoil appear to 10% or more is that in some cases exhibit a similar level as the topsoil. The average soil organic matter content of about 2.6%. This results shows that an excess of organic compost in the study area flows into subsoil and was mixed with the subsoil. The high EC value at the points outside the snow removal effect range level is not considered to be affected by the deicer. The results of the survey showed that the values were differently detected by agricultural activities, and that they should be approached in a complex way in their interpretation.
        9.
        2016.07 구독 인증기관 무료, 개인회원 유료
        Supply and demand patterns have dynamically changed in recent years due to the increased global competition. Firms have selected quality and price as competition components and have accomplished corporate innovation in order to achieve competitive advantage. Innovation has been recognized as the way to enhance corporate competitiveness and to continuously grow in churning global competition (Homburg, Schwemmle, & Kuehnl, 2015; Moon, Miller, & Kim, 2013). Although innovation becomes a common means to improve a firm’s performance, it has the limitation of achieving a firm’s strategic goal as a long-term strategy. Thus, firms need to have more fine-grained strategies to survive in dynamically changing business environment, such as design innovation (Moon et al., 2015). For example, Apple has produced its products (e.g., iPhone, iPod and iPad) focusing on innovative product design to influence consumer purchase intention. Design can lead to a distinct competitive advantage (Bolch, 1995). Furthermore, product design can be used by firms to create amd enhance brand recognition, as well as to increase firms’ value (Mozota, 2002). Brand experience positively influences customer satisfaction and brand loyalty (Brakus, Schmitt, & Zarantonello, 2009). Thus, we assume that design experience and product innovation have a positive effect on consumers’ purchase behavior and customer value. However, while the importance of design innovation is recognized, it is not easy to apply the design innovation to marketing due to the lack of relevant research in the field. In fact, relevant research on the influence of innovative new product design and design experience on customer value is scarce. Therefore, the purpose of this study is to investigate how brand experiences and innovative product design affect customer value. Successful innovation is accomplished by identifying customer needs first and developing innovative products to satisfy their needs (Hauser et al., 2006). Design is seen as the core of innovation and the moment when a new object is conceived of, devised, and shaped in a prototype form (Landwehr, Wentzel, & Herrmann, 2013). Verganti (2008) studies the concept of "user-centered design," which describes how companies can use design to improve their relationships with users and develop a better understanding of user needs. In this research, design innovation has three dimensions: aesthetic attributes, feature attributes, and emotional attributes. First, aesthetic attributes focus on the product design itself. The aesthetic appearance of a product has a large bearing on its potential market share (Liu, 2003). Second, feature attributes focus on the product features and functional aspects that are required to satisfy customer needs. Feature attributes enable performance that can give results in the operating process (Crawford & Di Benedetto, 2007). Third, emotional attributes focus on consumers’ feeling when they purchase a new product to satisfy their needs. Emotional attributes are generated by consumers’ experience when they purchase a new product in the store. The more the product design satisfies customer's emotional needs, the more customers’ attention is attracted to the purchase of a product (Mokarian, 2007). A product satisfying the aesthetic, feature, and emotional attributes through design innovation provides a new experience to customers (Desmet & Hekkert, 2007). A consumer’s purchase decision making is affected by both direct and indirect experience of using the product and the function of product (Brakus, Schmitt, & Zarantonello, 2009). Therefore, a designer comes to design the product, taking an interest in the experience that the product gives besides its shape and function. Product experiences occur when a customer interacts with the product ̶ for example, when customers search for, examine, and evaluate products (Hoch, 2002). The product experience can be direct, i.e. when there is physical contact with the product (Hoch & Ha 1986) or indirect, i.e. when a product is presented virtually or in an advertisement (Hoch & Ha 1986; Kempf and Smith 1998). Brand experience can be split into four dimensions (sensory, affective, intellectual, and behavioral), which are differentially evoked by various brands (Brakus, Schmitt, & Zarantonello, 2009). According to previous studies, these four experience dimensions (sensory, affective, intellectual, and behavioral experience dimensions) have an effect on customer satisfaction and customer loyalty. Customer value can be defined as the trade-off between the benefits and sacrifices as a customer purchases a product or service from a supplier (Ulaga & Chacour, 2001). Ulaga and Chacour presented three dimensions of customer value: product-related components, service-related components, and promotion-related components. The researchers argued that customer value could be an important strategic marketing tool to clarify a firm's proposition to customers. Product-related components are intrinsic product characteristics. Product quality is a key factor of relationship value (Ulaga, 2003). Customer value consists of product value and service value. Customer value can be enhanced by quality, diversity, payment, and service quality and decreased by price, convenience, and risk (Jarvenpaa & Todd, 2003). Service-related components include all aspects of service associated with the product. Various service components play an important role in differentiating a supplier's offering (Narus & Anderson, 1996). Promotion-related components include all items used to promote the product to the customer. For all purchasing processes, it is necessary to assess the perceived customer value, such as service quality and promotional quality (Qualls & Rosa, 1995). In the present study, we conducted a research survey with 300 subjects and analyzed the data. In order to test the reliability of questionnaire, Cronbach's alpha was used. In order to test the validity, an exploratory factor analysis was conducted. Measurement was made for 3 variables, i.e. design innovation, design experience, and customer value. Three variables (aesthetical attributes, feature attributes, and emotional attributes) were used for design innovation. Three types of attributes were introduced for a mobile phone design innovation. Four dimensions (sensory, affective, intellectual, behavioral) were measured using a technical design experience and a humanistic design experience. Three variables (product-related customer value, service-related customer value, and promotion-related customer value) were employed for customer value. The results of the analyses demonstrate that design innovation has a positive effect on design experience, while design experience has a positive effect on customer value. Aesthetic attributes of design innovation have a positive effect on technical design experience and humanistic design experience. Feature attributes have a positive effect on the technical design experience and the humanistic design experience. Emotional attributes have an effect on the technical design experience and the humanistic design experience. The technical design experience has a positive effect on product-related customer value, service-related customer value, and promotion-related customer value. The humanistic design experience has a positive effect on product-related customer value, service-related customer value and promotion-related customer value. This study will make it possible to empirically examine how customer's experience in design innovation affects customer value. Our results will provide a theoretical foundation for examining a relationship between variables regarding how design innovation influences customer value through design experience. It is intended to give a direction as to the design innovation of firms by clarifying and presenting antecedent factors having an effect that design innovation produces on customer value. The results of the present study will inspire designers to design in consideration of design experience. Finally, our study will provide marketers with guidelines as to how design experience can influence customer satisfaction and loyalty.
        3,000원
        10.
        2011.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Poly(vinyl chloride)-g-poly(oxyethylene methacrylate) (PVC-g-POEM) 가지형 공중합체를 원자전달라디칼 중합을 통해 합성하여 전기변색소자의 전해질에 적용하였다. 가소화된 고분자 전해질은 가소제로서 propylene carbonate (PC)/ethylene carbonate (EC) 혼합물을 도입하여 제조하였으며, Lithium tetrafluoroborate (LiBF4), lithium perchlorate (LiCIO4), lithium iodide (LiI) and lithium bistrifluoromethanesulfonimide (LiTFSI)를 사용하여 염의 종류에 따른 영향을 조사하였다. 광각 x-선 산란(WAXS)과 시차주사 열량법(DSC) 측정 결과 고분자 전해질의 구조와 유리전이온도(Tg)가 변하였고, 이는 POEM 내의 에테르의 산소와 리튬염 사이의 상호작용으로 인해 변했다는 것을 FT-IR 분광법을 통하여 확인하였다. 투과전자현미경(TEM) 측정 결과 PVC-g-POEM 가지형 공중합체의 미세상분리 구조가 PC/EC와 리튬염의 도입에도 변하지 않는 것을 관찰하였다. 가소화된 고분자 전해질은 poly(3-hexylthiophene) (P3HT) 전도성 고분자를 이용한 전기변색소자에 적용되었다.
        4,000원
        11.
        2011.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        운간초의 분화 품질을 향상시키기 위하여 ‘Kumoma’ 와 ‘Kumoma-Gusa’ 두 품종의 생장과 개화에 미치는 영향을 구명하고자 식물생장억제제 (PGRs) 4종을 처리 하였다. 식물생장억제제 종류와 처리농도는 paclobutrazol (10, 20, 40, 80 mg·L-1), flurprimidol (5, 10, 20, 40mg·L-1), daminozide (500, 1000, 2000, 4000mg·L-1), chlormequat (50, 100, 200, 400 mg·L-1)이고 엽면살포 와 토양관주 방법으로 처리하였다. Paclobutrazol 40 mg·L-1 처리는 운간초의 두 품종에서 초장과 화경 장을 줄이는데 효과적이었다. ‘Kumoma’ 품종에서, paclobutrazol 40 mg·L-1 엽면살포와 토양관주 처리방 법은 초장을 각각 12.6, 12.5 cm로, 화경장은 3.4, 3.3 cm로 줄일 수 있었다. ‘Kumoma-Gusa‘ 품종에서 는 paclobutrazol 토양관주는 처리 농도가 증가함에 따라 초장은 13.2-10.7 cm, 화경장은 3.9-2.0 cm까지 줄일 수 있었지만 꽃의 수는 대조구와 비교했을 때 현 저하게 감소하여서 20개까지 감소하였다. Flurprimidol 20mg·L-1 스프레이와 토양관주 처리는 두 품종 모두 초장과 화경장을 줄일 수 있었다. ‘Kumoma’ 품종에 서 flurprimidol 10 mg·L-1 스프레이 또는 토양관주 처리는 개화 품질을 향상시킬 수 있었고 대조구와 비 교해 꽃의 수는 44.7개 이상, 출하 일수는 5일 정도 빨리 출하 할 수 있었다. ‘Kumoma-Gusa‘ 품종에서 PGRs처리에 의한 초장 과 화경장 억제효과가 가장 큰 것은 paclobutrazol 80mg·L-1과 flurprimidol 40mg·L-1 이었고 paclobutrazol 과 flurprimidol 스프레이와 토양관주 처리에서 각각, 초장은 10.7, 9.9 cm, 화경장은 2.0, 1.5 cm 로 생장 억제효과가 가장 큰 것을 알 수 있었다. 그러나 flurprimidol 40 mg·L-1 토양관주 처리에서 출하일수는 농도에 따라 3-13일 정도 대조구보다 늦어졌고 꽃의 수는 15.6개로 가장 적은 것을 관찰 할 수 있었다. 두 품종 모두에서 daminozide 처리는 초장과 화경장 이 줄어들지 않았지만 ‘Kumoma’ 품종에서는 대조구 와 비교했을 때 꽃의 수가 증가하였다. Chlormequat 처리는 paclobutrazol 과 flurprimidol 처리와 비교했 을 때 화경장 감소효과는 작았고 처리 식물의 잎은 다른 처리에 비해 연한 녹색을 보여주었다. 두 품종 모두에서 chlormequat 과 daminozide 처리는 생육과 개화 품질에 효과적으로 영향을 주지는 않았지만 꽃의 수는 모든 처리농도에서 41개 이상을 보여주었고, ‘Kumoma-Gusa’ 품종에 chlormequat 토양관주 처리는 최대 꽃의 수 63개를 볼 수 있었다. 이번 결과들은 paclobutrazol 과 flurprimidol 처리가 운간초 분화의 품질 향상을 위한 화경장의 생육을 조 절하는 생장억제제로서 사용 될 수 있음을 보여 주었 고, ‘Kumoma’ 품종에서는 paclobutrazol 40 mg·L-1 스프레이는 생육특성을, flurprimidol 10 mg·L-1 토양관 주 방법은 개화관련 특성의 품질을 향상시키는 생장억 제제의 농도로 추천 될 수 있고, ‘Kumoma-Gusa’ 품종 에서는 flurprimidol 20mg·L-1 스프레이와 flurprimidol 5mg·L-1 토양관주 방법이 운간초 분화의 생육특성과 개 화품질을 향상시키는 생장억제제의 농도로 추천 될 수 있다.
        4,300원
        12.
        2005.06 구독 인증기관 무료, 개인회원 유료
        Cloned calves derived from somatic cell nuclear transfer (SCNT) have been frequently lost by sudden death at 1 to 3 month following healthy birth. To address whether placental anomalies are responsible for the sudden death of cloned calves, we compared protein patterns of 2 placentae derived from SCNT of Korean Native calves died suddenly at two months after birth and those of 2 normal placentae obtained from AI fetuses. Placental proteins were separated using 2-Dimensional gel electrophoresis. Approximately 800 spots were detected in placental 2-D gel stained with coomassie-blue. Then, image analysis of Malanie III (Swiss Institute for Bioinformatics) was performed to detect variations in protein spots between normal and SCNT placentae. In the comparison of normal and SCNT samples, 8 spots were identified to be up-regulated proteins and 24 spots to be down-regulated proteins in SCNT placentae, among which proteins were high mobility group protein HMG1, apolipoprotein A-1 precursor, bactenecin 1, tropomyosin beta chain, H+-transporting ATPase, carbonic anhydrase II, peroxiredoxin 2, tyrosine-rich acidic matrix protein, serum albumin precursor and cathepsin D. These results suggested that the sudden death of cloned calves might be related to abnormal protein expression in placenta.
        4,000원
        13.
        2017.12 KCI 등재 서비스 종료(열람 제한)
        본 연구에서는 그라비올라(Annona muricata) 잎으로부터 50% 에탄올 추출물, 에틸아세테이트 분획 및 아글리콘 분획을 제조하였고 이들 추출물/분획에 대하여 항산화 활성을 평가하였다. 1,1-Phenyl-2-picrylhydrazyl (DPPH) 라디칼 시험법을 이용한 자유라디칼 소거 활성, 루미놀 발광법을 이용한 총 항산화능 및 1O2 소광 효과를 평가하였다. 50% 에탄올 추출물, 에틸아세테이트 분획 및 아글리콘 분획의 라디칼 소거 활성 (FSC50)은 각각 45.6, 29.8 및 18.0 μ g/mL이었고, 총 항산화능(OSC50)은 4.4, 1.1 및 2.8 μ g/mL이었다. 에틸 아세테이트 분획의 총 항산화능은 수용성 항산화제로 잘 알려진 L-ascorbic acid (1.5 μ g/mL)보다 높은 항산 화능을 나타내었다. 1O2 소광 상수 실험 결과, 에틸아세테이트 및 아글리콘 분획은 비교물질로 사용된 L-ascorbic acid와 유사한 활성을 보여주었다. 1O2으로 유도된 적혈구 세포 손상에 있어서, 그라비올라 잎 50% 에탄 올 추출물은 농도 의존적(5-50 μ g/mL)으로 세포보호 활성을 나타내었다. 실험에 사용된 그라비올라 잎 추출 물의 에틸아세테이트 분획과 아글리콘 분획에 대하여 TLC 및 HPLC를 이용한 성분 분석을 수행하였다. 에틸아 세테이트 분획에서는 rutin (quercetin-3-O-rutinoside), kaempferol-3-O-neohesperidoside, nicotiflorin (kaempferol-3-O-rutinoside), p-coumaric acid을 확인하였다. 아글리콘 분획에서는 kaempferol이 존재함을 확인하였다. 이상의 결과들은 그라비올라 잎 추출물이 항산화 화장품 원료로서 응용 가능성이 있음을 시사한다.
        14.
        2016.10 서비스 종료(열람 제한)
        Background : Recently, ginseng (Panax ginseng C.A. Meyer.) berry has been used as a health-promoting supplements. Also, Mulberries (Morus alba L.) fruit have been used in traditional herbal medicine to treat and prevent diabetes. In this study, we measured the cytotoxicity after fermentation of the extracts in Panax Ginseng Berry and Mulberry Fruit. Methods and Results : The extracts were prepared by decoction for 3 hours in distilled water (100 g/L). The dried extract was then dissolved in phosphate-buffered saline (PBS) in preparation for use. Cell viability was examined by an MTT assay. RAW 264.7 cells were seeded at 1 × 104/mL densities in 96-well plates. Each grouping had a non-treated group as the control. The extracts were added to each well and incubated for 24 hours at 37°C and 5% CO2. The MTT solutions (5 mg/mL) were added to each well, and the cells were cultured for another 2 hours. The supernatant was then discarded, and 100 μL of dimethyl sulfoxide was added to each well. The optical density was read at 540 nm. Conclusion : Probiotics and prebiotics modulate the composition of human and domestic animal gut microbiota. The beneficial effects may result from suppression of harmful microorganisms or stimulation of organisms which contribute in a positive way to the nutrition and health of human and domestic animal. Recently, fermentation using microorganisms for the production of more effective compounds has been extensively studied. In particular, the novel pharmacological effects of a new compound generated by fermentation have been reported. Some previous studies have demonstrated that Fermented herbal medicine extract showed better bioactivity than normal herbal Plants extract when used at the same concentration.
        15.
        2012.09 KCI 등재 서비스 종료(열람 제한)
        Citrus is one of the major fruits produced in Korea. There are about 20 species mainly grown in Jeju Island, Korea. Four representative species, which are quite different in the shape of leaf and the taste of fruit, were selected and were used to profile the transcriptomes. These species are ‘Miyagawa Wase’ (C. unshiu Marcov.) satsuma mandarin, ‘Kiyomi’ (C. unshiu Marcov. × C. sinensis) mandarin hybrid, ‘Dangyuja’ (C. grandis) and ‘Natsudaidai’ (C. natsudaidai). Classification of the up-regulated and down-regulated genes using the Cluster of Orthologous Groups of proteins (COG) database reveals that the number of genes included in each group differed significantly among the four species. Several genes that showed significant differences in expression on the microarray were selected and their expression patterns were examined by reverse transcription- ploymerase chain reaction. Metabolic genes such as tyrosine decarboxylase and β-glucosidase ligase were found to be highly expressed in Miyagawa Wase, relative to other species. On the other hand, the expression level of mannose phosphate isomerase was lower in Miyagawa Wase. An efflux pump gene was found to be up-regulated in Kiyomi, whereas cinnamyl-alcohol dehydrogenase was down-regulated. β-carotene 15,15’-dioxygenase, which is involved in the vitamin metabolism, was up-regulated in Natsudaidai. Interspecific differentiations of gene expression are analyzed in terms of the metabolic pathways and their possible roles in citrus species.
        19.
        2007.03 KCI 등재 서비스 종료(열람 제한)
        A new single cross waxy corn (Zea mays L.) hybrid, “Miheugchal” with black kernel was developed by the Maize Experiment Station (MES), Gangwon-do Agricultural Research and Extension Services (GARES) in 2004. This hybrid, which has good eating quality and
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