• 제목/요약/키워드: bent

검색결과 812건 처리시간 0.022초

자비(煮沸), 증자(蒸煮) 및 약제처리(藥劑處理)가 상수리나무와 소나무의 휨가공성(加工性)에 미치는 영향(影響) (Effects of Boliing, Steaming, and Chemical Treatment on Solid Wood Bending of Quercus acutissima Carr. and Pinus densiflora S. et. Z.)

  • 소원택
    • Journal of the Korean Wood Science and Technology
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    • 제13권1호
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    • pp.19-62
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    • 1985
  • 본(本) 시험(試驗)은 국내(國內) 활엽수로서 중요한 참나무속(屬)의 상수리나무와 침엽수(針葉樹)의 대표적(代表的) 수종(樹種)인 소나무를 공시목(公試木)으로 선정(選定)하여 곡목가공분야(曲木加工分野)에서 널리 이용(利用)하는 자비법(煮沸法)과 증자법(蒸煮法)에 의한 휨가공성(加工性)을 조사(調査)하고, 이에 관련(關聯)된 인자(因子)로서 변(邊) 심재(心材), 연륜각도(年輪角度), 연화처리온도(軟化處理溫度), 연화처리시간(軟化處理時間), 목재함수율(木材含水率) 및 목재결함(木材缺陷) 등(等)의 영향(影響)과 휨가공(加工)후의 곡율반경변화(曲率半經變化) 및 약제처리(藥劑處理)에 의한 휨가공성(加工性)의 개선방법(改善方法)을 구명(究明)하기 위하여 실시(實施)되었다. 이 때 사용(使用)된 자비(煮沸)와 증자처리용(蒸煮處理用) 시편(試片)의 크기는 두께와 너비 15mm, 길이 350mm이고 약제처리용시편(藥劑處理試片)의 크기는 두께 5mm, 너비 10mm 및 길이 200mm로 제작(製作)하였으며, 시편(試片)의 함수율(含水率)은 자비처리(煮沸處理)에는 생재(生材)를 사용(使用)하고 증자처리(蒸煮處理)에는 15%로 조습(調濕)된 건조재(乾燥材)를 사용(使用)하였다. 또한 약제처리(藥劑處理)는 포화요소용액(飽和尿素溶液), 35% 포르말린 용액(溶液), 25% 폴리에칠렌(400) 수용액(水溶液) 및 25% 암모니아수에 5일간(日間) 상온(常溫)으로 침지(浸漬)한 우 휨가공(加工)을 행하였다. 본(本) 시험(試驗)에서 얻은 결과(結果)를 요약(要約)하면 다음과 같다. 1. 상수리나무와 소나무의 목재내부온도(木材內部溫度)는 자비(煮沸) 또는 증자처리시간(蒸煮處理時間)에 따라 초기(初期) 약(約) $30^{\circ}C$까지 완만(緩慢)한 상승(上昇)을 보이다가 그 후 직선적(直線的)으로 급상승(急上昇)하며 후기(後期) $80{\sim}90^{\circ}C$부터는 다시 완만(緩慢)해지는 경향(傾向)을 나타냈다. 2. 최종온도(最終溫度) $100^{\circ}C$까지 도달(到達)하는 데 소요(所要)되는 연화처리시간(軟化處理時間)은 목재(木材)의 두께에 비례(比例)하며 두께 15mm 각재(角材)에 대한 $25^{\circ}C$에서 $100^{\circ}C$까지의 소요시간(所要時間)은 상수리나무 9.6~11.2분(分), 소나무 7.6~8.1분(分)으로서 소나무의 연화속도(軟化速度)가 보다 빠르게 나타났다. 3. 증자처리시간(蒸煮處理時間)의 경과(經過)에 따른 목재(木材)의 함수율증가경향(含水率增加傾向)은 처음 약(約)4분(分)까지 급증(急增)하나 그후 점차(漸次) 둔화(鈍化)되어 상수리나무는 20분(分), 소나무는 15분경(分頃)부터 거의 직선적(直線的)으로 완만(緩慢)하게 증가(增加)하는 경향(傾向)을 나타냈다. 두께 15mm 각재(角材)에 대한 초기함수율(初期含水率) 15%에서 50분간(分間) 증자처리(蒸煮處理) 후의 함수율증가량(含水率增加量)은 상수리나무 3.6%, 소나무 7.4%로서 소나무의 흡습속도(吸濕速度)가 빠르게 나타났다. 4. 자비처리시간(煮沸處理時間)이 경과(經過)함에 따라 두 수종(樹種) 모두 기계적(機械的) 성질(性質)이 현저하게 감소(減少)하였으며, 60분간(分間) 자비처리(煮沸處理)에 의한 기계적(機械的) 성질(性質)의 감소율)減少率)은 압축강도(壓縮强度) 35.6~45.0%, 인장간도(引張强度) 12.5~17.5%, 휨강도(强度) 31.6~40.9% 및 휨탄성계수(彈性係數) 23.3~34.6%로 나타났다. 5. 변재(邊材)와 심재별(心材別) 최소곡률반경(最小曲律半徑)은 각각(各各) 상수리나무에서 60~80mm 및 90mm, 소나무에서 260~300mm 및 280~300mm로 두 수종(樹種) 모두 변재(邊材)의 휨가공성(加工性)이 양호하였다. 6. 상수리나무의 정목재(柾木材)와 판목재별(板目材別) 최소곡률반경(最小曲律半徑)은 모두 60~80mm로서 차이(差異)가 없었으나 소나무에서는 각각(各各) 240~280mm 및 260~300mm로 정목재(柾木材) 휨가공성(加工性)이 양호하였다. 7. 연화처리온도(軟化處理溫度)가 증가(增加)할수록 상수리나무와 소나무 모두 휨가공성(加工性)이 향상(向上)되었으며 휨가공(加工)을 위한 최저처리온도(最低處理溫度)는 각각(各各) $90^{\circ}C$$80^{\circ}C$로서 처리온도(處理溫度)에 대한 의존도(依存度)는 상수리나무에서 약간 높게 나타났다. 8. 연화처리시간(軟化處理時間)이 증가(增加)할수록 상승온도(上昇溫度)와 상응(相應)하여 휨가공성(加工性)을 향상(向上)시켰으나 최종온도(最終溫度)에 도달(到達)한 후에도 계속 연화(軟化)을 지속(持續)해야 비로서 최적연화상태(最適軟化狀態)를 나타냈다. 휨가공(加工)을 위한 최소처리시간(最少處理時間) 두께 15mm 각재(角材)에 대하여 상수리나무에서 자비처리시(煮沸處理時) 10분(分), 증자처리시(蒸煮處理時) 30분(分) 및 소나무에서 자비처리시(煮沸處理時) 10분(分), 증자처리시(蒸煮處理時) 20분(分)으로 나타났다. 9. 휨가공(加工)을 위한 상수리나무의 적정함수율(適定含水率)은 20%로 나타났으며 섬유포화점(纖維飽和點) 이상(以上)에서는 오히려 휨가공성(加工性)이 저하(低下)되었다. 반면(反面)에 소나무의 적정함수율(適定含水率)은 30% 이상(以上)을 필요(必要)로 하였다. 10. 본(本) 시험(試驗)에서 얻은 최적조건(最適條件)(Table 19)으로 휨가공(加工)을 실시(實施)한 결과(結果) 상수리나무의 최소곡률반경(最小曲律半徑)은 자비처리시(煮沸處理時) 80 mm, 증자처리시(蒸煮處理時) 50 mm이고 소나무에서는 자비처리시(煮沸處理時) 240 mm, 증자처리시(蒸煮處理時) 280 mm로서 상수리나무는 증자처리(蒸煮處理)의 연화효과(軟化效果)가 양호하였으나 소나무는 자비처리(煮沸處理)가 양호하였다. 11. 인장대철(引張帶鐵) 사용(使用)하지 않았을 경우 상수리나무와 소나무의 시편(試片)두께(t)와 최소곡률반경(最小曲律半徑)(r)의 비(比)(r/t)는 각각(各各) 자비처리시(煮沸處理時) 16.0 및 21.3, 증자처리시(蒸煮處理時) 17.3 및 24.0으로 나타났으나 인장대철(引張帶鐵) 사용(使用)하였을 때는 각각(各各) 자비처리시(煮沸處理時) 5.3 및 16.0, 증자처리시(蒸煮處理時) 3.3 및 18.7로서 휨가공성(加工性)의 현저한 향상(向上)을 나타냈다. 12. 미소(微小)한 옹이의 위치별(位置別) 상수리나무의 휨가공성(加工性)에 미치는 영향(影響)은 매우 심하게 나타났는 데 특히 옹이의 의치(位置)를 휨재(材)의 압축측(壓縮側)에 두고 곡률반경(曲律半徑) 100 mm로 휨가공(加工)하였을 때는 파양율(破壤率)이 90%로서 거의 휨가공(加工)이 불가능(不可能)하였다. 그러나 옹이를 인장측(引張側)에 두었을 경우에는 파양율(破壤率)이 10%에 불과(不過)하였다. 13. 곡률반경(曲律半徑) 300 mm로 휨가공(加工) 후 30 일간(日間) 실내조건(室內條件)에서 방치(放置)하였을 때의 곡률반경변화율(曲律半徑變化率)은 자비처리시(煮沸處理時) 4.0~10.3%, 증자처리시(蒸煮處理時) 13.0~15.0%로서 증자처리(蒸煮處理)에 의한 복원현상(復元現象)이 자비처리(煮沸處理)보다 심하게 나타났으며 에폭시수지(樹脂)를 도포(塗布)하여 방습처리(防濕處理) 하였을 경우에는 곡률반경변화율(曲律半徑變化率)이 -10~0%에 불과(不過)하였다. 14. 약제처리(藥劑處理)에 의한 가소성(可塑性) 효과(效果)는 35% 포르말린 용액(溶液)과 25% 폴리에칠렌 글리콜(400) 수용액(水溶液)에서는 나타나지 않았고 포화요소용액(飽和尿素溶液)과 25% 암모니아수에서는 나타났으나 증자처리(蒸煮處理)의 효과(效果)에는 미치지 못하였다. 그러나 약제처리(藥劑處理) 후 증자처리(蒸煮處理)를 병용실시(倂用實施)하였을 때는 증자처리(蒸煮處理)보다 10~24% 휨가공성(加工性)이 향상(向上)되었다. 15. 소서계수(塑性係數)와 곡률반경(曲律半徑)과의 관계(關係)는 하중(荷重)-변형계수(變形係數), 변형계수(變形係數) 및 에너지계수(係數) 모두 1% 수준(水準)에서 유의적(有意的)인 상관(相關)이 인정(認定)되므로 휨 가공용재(加工用材)의 품질지표(品質指標)로서 적합(適合)하였고 적합도(適合度)는 하중(荷重)-변형계수(變形係數), 에너지계수(係數) 및 변형계수(變形係數)의 순(順)으로 크게 나타났다.

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Perceptional Change of a New Product, DMB Phone

  • Kim, Ju-Young;Ko, Deok-Im
    • 마케팅과학연구
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    • 제18권3호
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    • pp.59-88
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    • 2008
  • Digital Convergence means integration between industry, technology, and contents, and in marketing, it usually comes with creation of new types of product and service under the base of digital technology as digitalization progress in electro-communication industries including telecommunication, home appliance, and computer industries. One can see digital convergence not only in instruments such as PC, AV appliances, cellular phone, but also in contents, network, service that are required in production, modification, distribution, re-production of information. Convergence in contents started around 1990. Convergence in network and service begins as broadcasting and telecommunication integrates and DMB(digital multimedia broadcasting), born in May, 2005 is the symbolic icon in this trend. There are some positive and negative expectations about DMB. The reason why two opposite expectations exist is that DMB does not come out from customer's need but from technology development. Therefore, customers might have hard time to interpret the real meaning of DMB. Time is quite critical to a high tech product, like DMB because another product with same function from different technology can replace the existing product within short period of time. If DMB does not positioning well to customer's mind quickly, another products like Wibro, IPTV, or HSPDA could replace it before it even spreads out. Therefore, positioning strategy is critical for success of DMB product. To make correct positioning strategy, one needs to understand how consumer interprets DMB and how consumer's interpretation can be changed via communication strategy. In this study, we try to investigate how consumer perceives a new product, like DMB and how AD strategy change consumer's perception. More specifically, the paper segment consumers into sub-groups based on their DMB perceptions and compare their characteristics in order to understand how they perceive DMB. And, expose them different printed ADs that have messages guiding consumer think DMB in specific ways, either cellular phone or personal TV. Research Question 1: Segment consumers according to perceptions about DMB and compare characteristics of segmentations. Research Question 2: Compare perceptions about DMB after AD that induces categorization of DMB in direction for each segment. If one understand and predict a direction in which consumer perceive a new product, firm can select target customers easily. We segment consumers according to their perception and analyze characteristics in order to find some variables that can influence perceptions, like prior experience, usage, or habit. And then, marketing people can use this variables to identify target customers and predict their perceptions. If one knows how customer's perception is changed via AD message, communication strategy could be constructed properly. Specially, information from segmented customers helps to develop efficient AD strategy for segment who has prior perception. Research framework consists of two measurements and one treatment, O1 X O2. First observation is for collecting information about consumer's perception and their characteristics. Based on first observation, the paper segment consumers into two groups, one group perceives DMB similar to Cellular phone and the other group perceives DMB similar to TV. And compare characteristics of two segments in order to find reason why they perceive DMB differently. Next, we expose two kinds of AD to subjects. One AD describes DMB as Cellular phone and the other Ad describes DMB as personal TV. When two ADs are exposed to subjects, consumers don't know their prior perception of DMB, in other words, which subject belongs 'similar-to-Cellular phone' segment or 'similar-to-TV' segment? However, we analyze the AD's effect differently for each segment. In research design, final observation is for investigating AD effect. Perception before AD is compared with perception after AD. Comparisons are made for each segment and for each AD. For the segment who perceives DMB similar to TV, AD that describes DMB as cellular phone could change the prior perception. And AD that describes DMB as personal TV, could enforce the prior perception. For data collection, subjects are selected from undergraduate students because they have basic knowledge about most digital equipments and have open attitude about a new product and media. Total number of subjects is 240. In order to measure perception about DMB, we use indirect measurement, comparison with other similar digital products. To select similar digital products, we pre-survey students and then finally select PDA, Car-TV, Cellular Phone, MP3 player, TV, and PSP. Quasi experiment is done at several classes under instructor's allowance. After brief introduction, prior knowledge, awareness, and usage about DMB as well as other digital instruments is asked and their similarities and perceived characteristics are measured. And then, two kinds of manipulated color-printed AD are distributed and similarities and perceived characteristics for DMB are re-measured. Finally purchase intension, AD attitude, manipulation check, and demographic variables are asked. Subjects are given small gift for participation. Stimuli are color-printed advertising. Their actual size is A4 and made after several pre-test from AD professionals and students. As results, consumers are segmented into two subgroups based on their perceptions of DMB. Similarity measure between DMB and cellular phone and similarity measure between DMB and TV are used to classify consumers. If subject whose first measure is less than the second measure, she is classified into segment A and segment A is characterized as they perceive DMB like TV. Otherwise, they are classified as segment B, who perceives DMB like cellular phone. Discriminant analysis on these groups with their characteristics of usage and attitude shows that Segment A knows much about DMB and uses a lot of digital instrument. Segment B, who thinks DMB as cellular phone doesn't know well about DMB and not familiar with other digital instruments. So, consumers with higher knowledge perceive DMB similar to TV because launching DMB advertising lead consumer think DMB as TV. Consumers with less interest on digital products don't know well about DMB AD and then think DMB as cellular phone. In order to investigate perceptions of DMB as well as other digital instruments, we apply Proxscal analysis, Multidimensional Scaling technique at SPSS statistical package. At first step, subjects are presented 21 pairs of 7 digital instruments and evaluate similarity judgments on 7 point scale. And for each segment, their similarity judgments are averaged and similarity matrix is made. Secondly, Proxscal analysis of segment A and B are done. At third stage, get similarity judgment between DMB and other digital instruments after AD exposure. Lastly, similarity judgments of group A-1, A-2, B-1, and B-2 are named as 'after DMB' and put them into matrix made at the first stage. Then apply Proxscal analysis on these matrixes and check the positional difference of DMB and after DMB. The results show that map of segment A, who perceives DMB similar as TV, shows that DMB position closer to TV than to Cellular phone as expected. Map of segment B, who perceive DMB similar as cellular phone shows that DMB position closer to Cellular phone than to TV as expected. Stress value and R-square is acceptable. And, change results after stimuli, manipulated Advertising show that AD makes DMB perception bent toward Cellular phone when Cellular phone-like AD is exposed, and that DMB positioning move towards Car-TV which is more personalized one when TV-like AD is exposed. It is true for both segment, A and B, consistently. Furthermore, the paper apply correspondence analysis to the same data and find almost the same results. The paper answers two main research questions. The first one is that perception about a new product is made mainly from prior experience. And the second one is that AD is effective in changing and enforcing perception. In addition to above, we extend perception change to purchase intention. Purchase intention is high when AD enforces original perception. AD that shows DMB like TV makes worst intention. This paper has limitations and issues to be pursed in near future. Methodologically, current methodology can't provide statistical test on the perceptual change, since classical MDS models, like Proxscal and correspondence analysis are not probability models. So, a new probability MDS model for testing hypothesis about configuration needs to be developed. Next, advertising message needs to be developed more rigorously from theoretical and managerial perspective. Also experimental procedure could be improved for more realistic data collection. For example, web-based experiment and real product stimuli and multimedia presentation could be employed. Or, one can display products together in simulated shop. In addition, demand and social desirability threats of internal validity could influence on the results. In order to handle the threats, results of the model-intended advertising and other "pseudo" advertising could be compared. Furthermore, one can try various level of innovativeness in order to check whether it make any different results (cf. Moon 2006). In addition, if one can create hypothetical product that is really innovative and new for research, it helps to make a vacant impression status and then to study how to form impression in more rigorous way.

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