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A Study on the Effects of Brand Individuality of Specialty Coffee Shops on Brand Loyalty (커피 전문점의 브랜드 개성이 브랜드 충성도에 미치는 영향에 관한 연구)

  • Kim, Joon-Seok;Choi, Sung-Hwan
    • Culinary science and hospitality research
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    • v.17 no.1
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    • pp.124-141
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    • 2011
  • The domestic food culture in Korea has gone through great changes, among which dining out is considered most prominent. These changes are caused by a number of factors: development of several related industries, increase in dining out chances, diversification of consumer needs, change in consumption awareness and quality, increase in disposable income, women's advance into the society, etc. Under these circumstances, the fast food industry has been experiencing slow growth, whereas family restaurants and take out coffee franchises are consistently increasing the number of restaurants and shops as a part of aggressive management to increase sales. This study aims, first, to examine the effects of consumer's brand individuality and satisfaction on brand trust, brand emotion, brand identification, and brand loyalty of specialty coffee shops. Subsequently, this study observes how consumer's brand individuality and satisfaction affect the formation of brand trust, brand emotion, brand identification, and brand loyalty in accordance with preferred type of specialty coffee shops, frequency of experience, and life style in order to establish relevant strategies. The results of this study are as follows. First, brand individuality had a positive effect on customer satisfaction. Second, customer satisfaction had a positive effect on brand trust. Third, customer satisfaction had a positive effect on brand loyalty. Fourth, customer satisfaction had a positive effect on brand emotion. Fifth, brand trust had a positive effect on brand loyalty. Sixth, brand emotion had a positive effect on brand loyalty. These results have the following implications. First, the dimensions of brand individuality are presented as a means to form brand loyalty, thereby demonstrating the significance of the effect. Accordingly, developing a proper brand individuality in forming brand loyalty is imperative. Second, consumers using specialty coffee shops had the greatest effect on the relation between dimensions of brand individuality and customer satisfaction in this study, while the interrelation between customer satisfaction and brand loyalty was not concretely supported in the preceding studies.

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Recovery of $SF_6$ gas from Gaseous Mixture ($SF_6/N_2/O_2/CF_4$) through Polymeric Membranes (고분자 분리막을 이용한 혼합가스($SF_6/N_2/O_2/CF_4$)로부터 $SF_6$의 회수)

  • Lee, Hyun-Jung;Lee, Min-Woo;Lee, Hyun-Kyung;Choi, Ho-Sang;Lee, Sang-Hyup
    • Membrane Journal
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    • v.21 no.1
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    • pp.22-29
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    • 2011
  • During the maintenance, repair and replacement process of circuit breaker, $SF_6$ reacted with input air in arc discharge, which led to the production of by-product gases (eg, $N_2$, $O_2$, $CF_4$, $SO_2$, $H_2O$, HF, $SOF_2$, $CuF_2$, $WO_3$). Among these various by-product gases, $N_2$, $O_2$, $CF_4$ is major component. Therefore, the effective separation process is necessary to recycle the $SF_6$ gas from the mixture gas containing $N_2$, $O_2$, $CF_4$. In this study, the membrane separation process was applied to recycle the $SF_6$ gas from the mixture gas containing $N_2$, $O_2$, $CF_4$. The concentration of $SF_6$ gas in gas produced from the electric power industry is over than 90 vol%. Therefore, we made the simulated gas containing $N_2$, $O_2$, $CF_4$, $SF_6$ which the concentration of $SF_6$ gas is minimum 90 vol%. From the results of membrane separation process of $SF_6$ gas from $N_2$, $O_2$, $CF_4$ $SF_6$ mixture gases, PSF membrane shown the highest recovery efficiency 92.7%, in $25^{\circ}C$ and 150 cc/min of retentate flow rate. On the other hand, PC membrane shown the highest recovery efficiency 74.8%, in $45^{\circ}C$ and 150 cc/min of retentate flow rate. Also, the highest rejection rate of $N_2$, $O_2$, $CF_4$ is 80, 74 and 58.9% seperately in the same operation condition of highest recovery efficiency. From the results, we supposed the membrane separation process as the effective $SF_6$ separation and recycle process from the mixture gas containing $N_2$, $O_2$, $CF_4$, $SF_6$.

Recycling of Acidic Etching Waste Solution Containing Heavy Metals by Nanofiltration (I): Evaluation of Acid Stability of Commercial Nanofiltration Membranes (나노여과에 의한 중금속 함유 산성 폐에칭액의 재생(I): 상용 나노여과 막의 산 안정성 평가)

  • Youm, Kyung-Ho;Shin, Hwa-Sup;Jin, Cheon-Deok
    • Membrane Journal
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    • v.19 no.4
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    • pp.317-323
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    • 2009
  • In this study the nanofiltration (NF) membrane treatment of a nitric acid waste solutions containing $Pb^{+2}$ heavy metal ion discharging from the etching processes of an electronics and semiconductors industry has been studied for the purpose of recycling of nitric acid etching solutions. Three kinds of NF membranes (General Electric Co. Duraslick NF-4040 membrane, Dow Co. Filmtec LP-4040 membrane and Koch Co. SelRO MPS-34 4040 membrane) were tested for their separation efficiency (total rejection) of $Pb^{+2}$ ion and membrane stability in nitric acid solution. NF experiments were carried out with a dead-end membrane filtration laboratory system. The membrane permeate flux was increased with the increasing storage time in nitric acid solution and lowering pH of acid solution because of the enhancing of NF membrane damage by nitric acid. The membrane stability in nitric acid solution was more superior in the order of Filmtec LP-4040 < Duraslick NF-4040 < SelRO MPS-34 4040 membrane. The total rejection of Pb+2 ion was decreased with the increasing storage time in nitric acid solution and lowering the pH of acid solution. The total rejection of $Pb^{+2}$ ion after 4 months NF treatment was decreased from 95% initial value to 20% in the case of Duraslick NF-4040 membrane, from 85% initial value to 65% in the case of SelRO MPS-34 4040 membrane and from 90% initial value to 10% in the case of Filmtec LP-4040 membrane. These results showed that SelRO MPS-34 4040 NF membrane was more suitable for the treatment of an acidic etching waste solutions containing heavy metal ions.

Agronomic Characteristics and Seed Quality of Cowpea (Vigna unguiculata L.) Germplasm (동부 유전자원의 작물학적 특성과 종실품질)

  • Kim, Dong-Kwan;Son, Dong-Mo;Choi, Jin-Gyung;Shin, Hae-Ryong;Choi, Kyeong-Ju;Lee, Jeongran;Lee, Kyung-Dong;Rim, Yo-Sup
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.58 no.1
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    • pp.1-7
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    • 2013
  • The purpose of this study was to provide basic information for breeding cowpeas (Vigna unguiculata L.) by investigating the crop characteristics of 245 accessions of cowpea collected in Korea and abroad. All specimens flowered within 41 to 50 days (51.5%) or 51 to 60 days (43.7%) of sowing and matured 21 to 30 days (53.9%) or 31 to 40 days (23.7%) from flowering. Thus, the total time from sowing to maturity was either 71 to 80 days (26.9%) or 81 to 90 days (23.4%) for all specimens. The accessions were classified into indeterminate type (72.7%), intermediate type (25.7%) and determinate type (1.6%) based on growth; prostrate type (78.8%) and erect type (21.2%) based on plant type; heart shape (98.4%) and lanceolate (1.6%) based on leaflet shape; and purple (85.2%), white (13.6%) and light green (1.2%) based on corolla color. The accessions were classified into brown (54.7%) and yellowish brown (37.6%) based on color at pod maturity; and downward (90.6%), middle (5.7%) and standing upright (3.7%) based on pod setting position. Seed coat color varied as 25.3% were brown, 23.3% were black, and 20.8% were white. Seed shape also varied as 66.9% were egg-shaped, 24.9% were rectangular and 8.2% were kidney-shaped. Pod lengths ranged from 10.1-20.0 cm and from 20.1-30.0 cm in 89.0% and 8.6% of specimens, respectively. There were 12.1-15.0, 9.1-12.0, and 15.1-18.0 seeds per pod in 62.0%, 25.7% and 9.1% of specimens, respectively. The weight of one hundred seeds ranged from 15.1-20.0 g (37.6%) and 10.1-15.0 g (28.6%). Seed yields per plant were 100.1-200.0 g (52.7%), less than 100 g (22.9%), and 200.1-300.0 g (15.9%). The starch content in the seeds of the seven selected resources ranged from 44.1 to 57.0% while the protein content ranged from 23.3 to 27.5% with significant differences. The sucrose content ranged from 1.46 to 2.03%, also with significant differences.

A Study on the Impact Factors of Contents Diffusion in Youtube using Integrated Content Network Analysis (일반영향요인과 댓글기반 콘텐츠 네트워크 분석을 통합한 유튜브(Youtube)상의 콘텐츠 확산 영향요인 연구)

  • Park, Byung Eun;Lim, Gyoo Gun
    • Journal of Intelligence and Information Systems
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    • v.21 no.3
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    • pp.19-36
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    • 2015
  • Social media is an emerging issue in content services and in current business environment. YouTube is the most representative social media service in the world. YouTube is different from other conventional content services in its open user participation and contents creation methods. To promote a content in YouTube, it is important to understand the diffusion phenomena of contents and the network structural characteristics. Most previous studies analyzed impact factors of contents diffusion from the view point of general behavioral factors. Currently some researchers use network structure factors. However, these two approaches have been used separately. However this study tries to analyze the general impact factors on the view count and content based network structures all together. In addition, when building a content based network, this study forms the network structure by analyzing user comments on 22,370 contents of YouTube not based on the individual user based network. From this study, we re-proved statistically the causal relations between view count and not only general factors but also network factors. Moreover by analyzing this integrated research model, we found that these factors affect the view count of YouTube according to the following order; Uploader Followers, Video Age, Betweenness Centrality, Comments, Closeness Centrality, Clustering Coefficient and Rating. However Degree Centrality and Eigenvector Centrality affect the view count negatively. From this research some strategic points for the utilizing of contents diffusion are as followings. First, it is needed to manage general factors such as the number of uploader followers or subscribers, the video age, the number of comments, average rating points, and etc. The impact of average rating points is not so much important as we thought before. However, it is needed to increase the number of uploader followers strategically and sustain the contents in the service as long as possible. Second, we need to pay attention to the impacts of betweenness centrality and closeness centrality among other network factors. Users seems to search the related subject or similar contents after watching a content. It is needed to shorten the distance between other popular contents in the service. Namely, this study showed that it is beneficial for increasing view counts by decreasing the number of search attempts and increasing similarity with many other contents. This is consistent with the result of the clustering coefficient impact analysis. Third, it is important to notice the negative impact of degree centrality and eigenvector centrality on the view count. If the number of connections with other contents is too much increased it means there are many similar contents and eventually it might distribute the view counts. Moreover, too high eigenvector centrality means that there are connections with popular contents around the content, and it might lose the view count because of the impact of the popular contents. It would be better to avoid connections with too powerful popular contents. From this study we analyzed the phenomenon and verified diffusion factors of Youtube contents by using an integrated model consisting of general factors and network structure factors. From the viewpoints of social contribution, this study might provide useful information to music or movie industry or other contents vendors for their effective contents services. This research provides basic schemes that can be applied strategically in online contents marketing. One of the limitations of this study is that this study formed a contents based network for the network structure analysis. It might be an indirect method to see the content network structure. We can use more various methods to establish direct content network. Further researches include more detailed researches like an analysis according to the types of contents or domains or characteristics of the contents or users, and etc.

Development of Customer Sentiment Pattern Map for Webtoon Content Recommendation (웹툰 콘텐츠 추천을 위한 소비자 감성 패턴 맵 개발)

  • Lee, Junsik;Park, Do-Hyung
    • Journal of Intelligence and Information Systems
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    • v.25 no.4
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    • pp.67-88
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    • 2019
  • Webtoon is a Korean-style digital comics platform that distributes comics content produced using the characteristic elements of the Internet in a form that can be consumed online. With the recent rapid growth of the webtoon industry and the exponential increase in the supply of webtoon content, the need for effective webtoon content recommendation measures is growing. Webtoons are digital content products that combine pictorial, literary and digital elements. Therefore, webtoons stimulate consumer sentiment by making readers have fun and engaging and empathizing with the situations in which webtoons are produced. In this context, it can be expected that the sentiment that webtoons evoke to consumers will serve as an important criterion for consumers' choice of webtoons. However, there is a lack of research to improve webtoons' recommendation performance by utilizing consumer sentiment. This study is aimed at developing consumer sentiment pattern maps that can support effective recommendations of webtoon content, focusing on consumer sentiments that have not been fully discussed previously. Metadata and consumer sentiments data were collected for 200 works serviced on the Korean webtoon platform 'Naver Webtoon' to conduct this study. 488 sentiment terms were collected for 127 works, excluding those that did not meet the purpose of the analysis. Next, similar or duplicate terms were combined or abstracted in accordance with the bottom-up approach. As a result, we have built webtoons specialized sentiment-index, which are reduced to a total of 63 emotive adjectives. By performing exploratory factor analysis on the constructed sentiment-index, we have derived three important dimensions for classifying webtoon types. The exploratory factor analysis was performed through the Principal Component Analysis (PCA) using varimax factor rotation. The three dimensions were named 'Immersion', 'Touch' and 'Irritant' respectively. Based on this, K-Means clustering was performed and the entire webtoons were classified into four types. Each type was named 'Snack', 'Drama', 'Irritant', and 'Romance'. For each type of webtoon, we wrote webtoon-sentiment 2-Mode network graphs and looked at the characteristics of the sentiment pattern appearing for each type. In addition, through profiling analysis, we were able to derive meaningful strategic implications for each type of webtoon. First, The 'Snack' cluster is a collection of webtoons that are fast-paced and highly entertaining. Many consumers are interested in these webtoons, but they don't rate them well. Also, consumers mostly use simple expressions of sentiment when talking about these webtoons. Webtoons belonging to 'Snack' are expected to appeal to modern people who want to consume content easily and quickly during short travel time, such as commuting time. Secondly, webtoons belonging to 'Drama' are expected to evoke realistic and everyday sentiments rather than exaggerated and light comic ones. When consumers talk about webtoons belonging to a 'Drama' cluster in online, they are found to express a variety of sentiments. It is appropriate to establish an OSMU(One source multi-use) strategy to extend these webtoons to other content such as movies and TV series. Third, the sentiment pattern map of 'Irritant' shows the sentiments that discourage customer interest by stimulating discomfort. Webtoons that evoke these sentiments are hard to get public attention. Artists should pay attention to these sentiments that cause inconvenience to consumers in creating webtoons. Finally, Webtoons belonging to 'Romance' do not evoke a variety of consumer sentiments, but they are interpreted as touching consumers. They are expected to be consumed as 'healing content' targeted at consumers with high levels of stress or mental fatigue in their lives. The results of this study are meaningful in that it identifies the applicability of consumer sentiment in the areas of recommendation and classification of webtoons, and provides guidelines to help members of webtoons' ecosystem better understand consumers and formulate strategies.

The Study about Popularization of Gardening and Its Development Process in the UK - Focused on the Royal Horticultural Society in the 19th Century - (영국 정원문화의 대중화 전개 양상에 대한 연구 - 19세기 왕립원예협회(RHS)의 활동을 중심으로 -)

  • Cho, Hye-Ryeong;Sung, Jong-Sang
    • Journal of the Korean Institute of Landscape Architecture
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    • v.44 no.3
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    • pp.47-55
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    • 2016
  • RHS is a core organization with huge influences on the expansion of the base for the garden culture and industry. This study aimed to examine the meaning and value of the professional charity's role through the appearance background and developmental process of RHS. The passion for plant collection in the Victorian Age of the $19^{th}$ century became the background of establishing the society. Such background of the times and the root of the society are deeply related to the British civil garden culture. The consideration of the forming process of RHS and the study can be summarized as below. First, the professional introduction of exotic plants by plant hunters was developed into an organization supporting professional plant research through collection, sampling, and records, which led to the development of horticulture techniques, growth of plant nursery businesses and established the foundation of the civil garden culture in the UK. Second, after John Loudon was involved in RHS, inspired by the press editing more practical information contents, middle-class and women became new patrons to gardening. Therefore, the care of gardens became a source of agreeable domestic recreation, especially to the female sex. Third, $19^{th}$ century plant collection and exhibition was seen in the Chelsea Flower Show which a key role beyond the UK garden culture. Fourth, those acts of RHS and modernity in $19^{th}$ developed British middle-class domestic gardens which have the character of the ordinary and national garden style in the UK. Such history and activities of RHS are connected to the national status as a country of gardens, which suggests clues to practical measures and values we should aim for in order to settle citizen-centered garden culture.

A Study of the Gwanbok (1st period) of Meritorious Vassals' Portraits in the Joseon Dynasty (조선시대 공신초상(功臣肖像)의 관복(제1기) 고찰)

  • Kim, Migyung;Lee, Eunjoo
    • Korean Journal of Heritage: History & Science
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    • v.53 no.2
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    • pp.180-203
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    • 2020
  • In this study, the period before the Gwanbok of meritorious vassals' portraits was expressed in the acheongsaek-Heuk-Danryung was defined as the first period, and the costumes worn in portraits of meritorious vassals from Gaeguk (1392) in the early Joseon Dynasty to Jwali (1471) during the era of King Seongjong were reviewed. The portraits(1476) of Jeokgae meritorious vassals (1467) depicted as the Gwanbok of acheongsaek Heuk-Danryung were excluded. Among the copies that are currently considered to be portraits of meritorious vassals belonging to the first period, the portraits of Lee-je, Lee Cheon-woo, Ma Cheon-mok, Shin Suk-ju, Seol Gye-jo, and Lee Sung-won were selected, and the formative characteristics of Gwanbok components were examined. The Samo of Sam-Gongsin in the early Joseon Dynasty had a low height, a rounded end, and the side wings were narrow and short. However, since King Danjong, Jeongnan·Jwali meritorious vassals retained a higher form, and the side wings were twice as long. It was also confirmed that the pattern was not expressed in the side wings. The Danryung was expressed in light-colored Danryung without specific colors at the beginning of the country. After King Sejong, the Heuk-Danryung system for Yebok began, but it was not reflected in the Gwanbok of meritorious vassals' portraits, and was expressed as damhongsaek-Danryung after King Danjong. The pattern was not expressed on the exterior of the Danryung, and inner-wrinkled Mu was expressed on the side line. The Dapho and Cheolrik, the undergarments of the Danryung, were also confirmed as being blue (the Dapho) and green (the Cheolrik) after the Jeongnan meritorious vassals. The early Sam-Gongsin's Pumgye was expressed by rank belt, but as the system of rank badge was established after King Danjong, it began to express the Pumgye by rank badge and rank belt. Among the portraits of meritorious vassals, the rank badge was expressed only in the portrait of Sin Suk-ju, a Jeongnan meritorious vassal. As Hwaja worn on the Danryung, Heuk-hwa were confirmed in the Sam-Gongsin portraits of the early Joseon Dynasty. However, in the portraits of Jeongnan and Jwali meritorious vassals after King Danjong, the Baek-hwa was confirmed. In addition, in the seam parts of the Heuk-hwa and Baek-hwa identified in some portraits of meritorious vassals, Hwi decorated with yeongeumsa were identified, and it was found that the Hwaja decorated with Hwi were the Hyeopgeum-hwa worn by the 3rd rank and above.

A Study of Industrial Patients from Selected General in the Kyung Pook and Taegu City areas (일부지역 산업재해환자 실태 조사 연구 -대구${\cdot}$경북지역 일부 종합병원 중심으로-)

  • Huh, Choon-Bok
    • The Journal of Korean Physical Therapy
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    • v.3 no.1
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    • pp.151-174
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    • 1991
  • The purpose of this study is to research the actual conditions of industrial accident patients and to produce worker satisfaction and a rational and effective counter measure plan. Direct interviews with 179 cases (in and out patients) were carried out during a three month period from April to July 1990, at six hospitals : two general hospitals Sun Lin and Sung Mo in Po Hang, and four general hospitals in Taegu : Kyung pooh University Hospital, Dong San Medical Center, Young Nam Medical Center and Catholic Hospital. The results of this study are summarized as fellows : 1. Among the 179 cases, $51.6\%$ were male and $48.4\%$ were female. The two largest age groups were 30-39, $31.8\%$ and 20-29, $27.4\%$. Among the 179 cases, $51.6\%$ were married, the largest family number was 2 to 3, $41.1\%$ and 4 to 5, $25.6\%$. Educationally, graduation from high school was the largest group, $46.4\%$ among ,the patients, followed by middle school and primary school. The largest group income level was from 40-69 만원, $45.2\%$. The largest group of patients who worked over 50 hrs. a week was $52.0\%$. The largest group of patients who worked less than 1 year was $44.7\%$, of the patients in work places of less than 100 people, $60.3\%$ were injured and in work places of 100-299 people, $20.1\%$ were injured. In manufacturing, the largest group injured was $55.3\%$, the next group was transport, storage, communication. The largest group of production workers injured was $40.2\%$. 2. The cause of injury in the largest group was facility problems, $33.5\%$. The next group was unsafe habits, $30.2\%$ ; a lack of safety knowledge, $17.9\%$ ; and insufficient supervision, $12.3\%$. The 30-39 year age group head the highest number of injuries, $40.4\%$ ; work places with more than 10 years of work, $44.4\%$ ; work places with more than 1000 people, $56.3\%$ and mining accidents, $80.0\%$. Among. these groups the highest cause of injury was due to facility problems. 3. The accident pattern showed machinery injuries $28.5\%$ as the largest group, followed by falls & falling objects $17.3\%$, fire & electric $15.1\%$, strucke by an object $14.5\%$, followed by overaction and vehicular accidents. The accident pattern showed $46.4\%$ among workers over the 50 year age group, workers in the 5-10 year group, $50.0\%$ ; places employing more than 1000 workers, $35.3\%$ ; construction $73.7\%$, and construction workers $57.1\%$, among these fall & falling objects caused the greatest number of injuries. 4. The largest group of injuries was fractures $54.8\%$, trauma $14.5\%$, amputation $11.7\%$, open wound, and burns. The largest number of fractures occurred in people in the 30-39 year age group, $63.2\%$ : over 10 years of work, $55.0\%$ ; in work places of 300-490 people, $63.6\%$ ; construction $63.2\%$ and general workers $57.2\%$. 5. The largest group of injuries was upper extremity $45.3\%$, lower extremity $24.0\%$, trunk $18.5\%$ and head or neck $12.2\%$. Of these groups, upper extremity injuries were the highest in those less than 20 years old $75.0\%$, less than 1 year or work $59.5\%$, in work places of 500-999 people $60.0\%$, manufacturing $56.6\%$ and production workers $55.6\%$. 6. Periods of injury showed 34 people injured in September, to be the largest followed by October, 32 ; August, 22 people : July, 19 people and the lowest December, 2 people. During the week, Friday had the largest group injured, 35 people ; followed by Saturday, 26 people and the lowest was Wednesday, 17 people, During the day 1400 hours had the largest group injured, 38 people ; followed by 800 hours, 31 people. 7. On a basis of 5 as the highest mark, the average, according to worker satisfaction showed facility safety 3.55, work environment 3.47, income 3.44, job 3.21 and treatment 2.98. 8. The correlation between general characteristics and injury showed that age was directly correlated to the duration of work (r=2591) p<0.01, age was directly correlated to industry (r=2311) p<0.01, and the duration was directly correlated to occupation (r=4372) p<0.001.

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The Effect of Aging Treatment on the High Temperature Fatigue Fracture Behavior of Friction Welded Domestic Heat Resisting Steels (SUH3-SUS 303) (마찰용접된 국산내열 강 (SUH3-SUS303 )의 시효열처리가 고온피로강도 및 파괴거동에 미치는 영향에 관한 연구)

  • Lee, Kyu-Yong;Oh, Sae-Kyoo
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.17 no.2
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    • pp.93-103
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    • 1981
  • It is well-known that nowadays heat resisting and anti-corrosive materials have been widely used as the components materials of gas turbines, nuclear power plants and engines etc. In the fields of machine production industry. And materials for engine components, like as the exhaust valve of internal combustion engine, have been required to operate under the high temperature range of $700^{\circ}C$-$800^{\circ}C$ and high pressured gas with repeated mechanical load for the high performance of engines. For these components, friction welding for bonding of dissimilar steels can be applied for in order to obtain process shortening, production cost reduction and excellent bonding quality. And age hardening recently has been noticed to the heat resisting materials for further strengthening of high temperature strength, especially high temperature fatigue strength. However, it is difficult to find out any report concerning the effects of age hardening for strengthening high temperature fatigue strength to the Friction welded heat resisting and anti-corrosive materials. In this study the experiment was carried out as the high temperature rotary bending fatigue testing under the condition of $700^{\circ}C$ high temperature to the friction welded domestic heat resisting steels, SUH3-SUS303, which were 10hr., 100hr. aging heat treated at $700^{\circ}C$ after solution treatment 1hr. at $1, 060^{\circ}C$ for the purpose of observing the effects of the high temperature fatigue strength and fatigue fracture behaviors as well as with various mechanical properties of welded joints. The results obtained are summarized as follows: 1) Through mechanical tests and micro-structural examinations, the determined optimum welding conditions, rotating speed 2420 rpm, heating pressure 8kg/mm super(2), upsetting pressure 22kg/mm super(2), the amount of total upset 7mm (heating time 3 sec and upsetting time 2 sec) were satisfied. 2) The solution treated material SUH 3, SUS 303, have the highest inclination gradient on S-N curve due to the high temperature fatigue testing for long time at $700^{\circ}C$. 3) The optimum aging time of friction welded SUH3-SUS 303, has been recognized near the 10hr. at $700^{\circ}C$ after the solution treatment of 1hr. at $1, 060^{\circ}C$. 4) The high temperature fatigue limits of aging treated materials were compared with those of raw material according to the extender of aging time, on 10hr. aging, fatigue limits were increased by SUH 3 75.4%, SUS 303 28.5%, friction welded joints SUH 3-SUS 303 44.2% and 100hr. aging the rates were 64.9%, 30.4% and 36.6% respectively. 5) The fatigue fractures occurred at the side of the base matal SUS303 of the friction welded joints SUH 3-SUS 303 and it is difficult to find out fractures at the friction welding interfaces. 6) The cracking mode of SUS 303, SUH 3-303 is intergranular in any case, but SUH 3 is fractured by transgranular cracking.

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