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Characterization of Low-Temperature Pyrolysis and Separation of Cr, Cu and As Compounds of CCA-treated Wood (CCA (Chromated Copper Arsenate) 처리 목재의 저온 열분해와 CCA 유효 성분분리 특성)

  • Lim, Kie-Pyo;Lee, Jong-Tak;Bum, Jung-Won
    • Journal of the Korean Wood Science and Technology
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    • v.35 no.1
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    • pp.73-80
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    • 2007
  • This study was carried out to separate the heavy toxic metals in eco-building materials by low-temperature pyrolysis, especially arsenic (As) compounds in CCA wood preservative as a solid in char. The pyrolysis was carried out to heat the CCA-treated Hemlock at $280^{\circ}C$, $300^{\circ}C$, $320^{\circ}C$, and $340^{\circ}C$ for 60 mins. Laboratory scale pyrolyzer composed of [preheater$\rightarrow$pyrolyzer$\rightarrow$1st water scrubber$\rightarrow$2nd bubbling flask with 1% $HNO_3$ solution$\rightarrow$vent], and was operated to absorb the volatile metal compound particulates at the primary water scrubber and the secondary nitric acid bubbling flask with cooling condenser of $4^{\circ}C$ under nitrogen stream of 20 mL/min flow rate. And the contents of copper, chromium and arsenic compounds in its pyrolysis such as carbonized CCA treated wood, 1st washing and 2nd washing liquors as well as its raw materials, were determined using ICP-AES. The results are as follows : 1. The yield of char in low-temperature pyrolysis reached about 50 percentage similar to the result of common pyrolytic process. 2. The higher the pyrolytic temperature was, the more the volatiles of CCA, and in particular, the arsenic compounds were to be further more volatile above $320^{\circ}C$, even though the more repetitive and sequential monitorings were necessary. 3. More than 85 percentage of CCA in CCA-treated wood was left in char in such low-temperature pyrolytic condition at $300^{\circ}C$. 4. Washing system for absorption of volatile CCA in this experiment required much more contacting time between volatile gases and water to prevent the loss of CCA compounds, especially the loss of arsenic compound. 5. Therefore, more complete recovery of CCA components in CCA-treated wood required the lower temperature than $320^{\circ}C$, and the longer contacting time of volatile gases and water needed the special washing and recovery system to separate the toxic and volatile arsenic compounds in vent gases.

Nursing research issues and trends : views from Korea (우리나라 간호연구의 현황과 문제)

  • Oh, Kasil;Sin, Hee-Sun;Kim, Hee-Soon
    • The Korean Nurse
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    • v.31 no.3
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    • pp.76-87
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    • 1992
  • The purposes of study was: 1. To identify the direction and scope of research activities in Korean Nursing. 2. To discuss the unique problems present in Korea that warrant nursing research. 3. To delineate the factors that facilitate and/or hinder nursing research in Korea. This study was conducted at six colleges of nursing in Korea. The schools which were selected had doctoral programs at the time, the data were collected in 1990. Four of the schools were located in the metropolitan area of the capital city, Seoul, and two were in two other cities similar in size. The total population of the study was 283 nurses. The instrument for the research was the English version of Research Profile Questionnaire which was translated into Korean by the researchers and was validated in its translation by two professors. A pretest procedure was done before the data collection process. Of the population of 283, 210 subjects received the questionnaire and 150 subjects responded(71.4%). Excluding incomplete questionnaires, 141 questionnaires were utilized for data analysis. Data were analyzed using descriptive statistics. Responses to open-ended questions were content analyzed for themes and categories. Results of the study were as follows : Respondents currently , involved in nursing research numbered 108(76.6%), but 33(23.4%) did not have any research experience. The inexperienced respondenLs tended to be younger than the experienced subjects and most( 60.6%) were employed in hospitals, while 82.4 percent of the experienced nurses were employed in nursing schools. Among the respondents with research experience, 68.5 percent were involved in one to three projects and 31.5 percent were engaged in four or more projects. The experienced nurses indicated that nursing research in Korea is active. On the other hand, the responses of the inexperienced were that nursing research is not active. The most frequently selected research subjects were patients(76.9%, 83 respondents) followed by nurses, healthy persons and nursing students. The relatively high percentage of healthy persons as study subjects, could be explained as a concern of nurses for healthy persons as well as for ill patients. The aforememioned literature review showed a dramatic change in the kinds of study subjects; approximately 33 percent were patients but 25 percent were healthy subjects of various ages. The hospital was the prevailing research setting(67.6%) but at the same time various community settings were used. This is a changing phenomena in nursing research of Korea. Current research designed to build on previous studies amounted to 75 percent; about 39.8 percem were theory and hypothesis generated. Over 65 recommended additional research focusing on hypothesis-testing 0:' theory building. The previously quoted literature review found that only 4.0 percent of the study quescions were developed from a theoretical framework. The most frequently listed current major focus of nursmg research was stress and adaptation. Patients with cancer, pain, social support and care of the elderly were the next most frequently reported. These concerns may reflect problems associated with a technological and industrializing societyl. The most frequently identified problem was lack of clinical research. The need for replication research and research that contributes to the accumulation of nursing knowledge were found to be rare in Korean research. A need for theory testing and theory construction research was also identified. Although advanced statistical methods were often utilized in nursing research, the results were frequently considered by the interviewers not to be applicable in practice, and readers had difficulty in comprehending the findings. Even though the number of clinical nurses involved in research is increasing, it is still considered inadequate. Among 108 respondents, 83(76.9%) gave lack of time as a barrier to conducting nursing research. Over fifty percent of the respondents reported lack of funding or, personally, low confidence in research skills as barriers. The respondents offered 183 suggestions for future emphasis in nursing research. Among the 51 areas of emphasis, clinical research received the highest number and nursing intervention was next. The findings suggested that nursing research should be based on theory, be related to practice and relevant to the situation of a unique Korean culture.

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Original Landscape of MuGi-YeonDang and Yuhoejeong Pavilion Area in Chirwon through (<하환정도(何換亭圖)>를 통해 본 칠원 무기연당(舞沂蓮塘)과 유회정(有懷亭) 일곽의 원형경관)

  • Rho, Jae-Hyun;Son, Hee-Kyung;Park, Tae-Hee
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.35 no.4
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    • pp.1-13
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    • 2017
  • This thesis aims to research the original landscape of an area in Chirwon by comparing and interpreting the current and the former landscape of the time around 1860, in which was created. Inside the painting, MuGi-YeonDang(舞沂蓮塘), its nearby garden facilities and landscape are described. The conclusions of the research are as follows. Around the inner garden(內園) called Gukdam(菊潭), core spaces of Mugi-YeonDang were Hahwanjeong(何換亭) and Pungyongnu(風浴樓). After 1971, Chunghyosa(忠孝祠), Yeongjeonggak(影幀閣) which was built as inheritance of Giyangseowon (沂陽書院), and other buildings were added. On the opposite of Hahwanjeong, there is a designed pond inside Gukdam, in which three pieces of bizarre stones and colorful flower plants and trees reside. In the middle of the pond, there is an center island(中島), constructed with Bonghwangseok(鳳凰石) and Napduseok(衲頭石). Two different kinds of trees are settled on top of the stones, and one of them is identified as a maple. In the external scenery(外境), Jakdaesan Mountain and Cheonjusan Mountain are located at the upper part of Mugi-Yeondang, and Bibo Forest(裨補林), which does not exist anymore, was located at the lower part of it. A notable achievement in own research was to discover the Ju family's graveyard(朱氏墓群) consisted of more than 10 murals at the lower part of Mt. Jakdaesan in the outer space and the remains of 'Byeoreop(別業) Yuhoejeong(有懷亭)' at the nearby Sanjeong-ri(山亭里) area, which was the Ju family's gravesite(Seonsan, 先山). The discovered remains showed the presence of a square pond(方塘) and an island in the center of it(中島) in the form of Seokgasan(an artificial mountain made with stones), a stone monument called Mangchudae(望楸臺), etc. The Seokgasan was consisted of processed natural stones, and layers of the stones were piled up for it. On the side of the layered stones, 'Gyeongam(敬嵒)' and 'Sesim(洗心)' are engraved. Especially, Gyeongja(letter Gyeong, 敬字) is a copy of the Gyeongja Rock(敬字岩) of Sosu-Seowon(紹修書院), which is a symbolic garden language mutually used in the signboards of Pungyongnu and Musansa(武山祠), a place built to enshrine Ju, Sebung(周世鵬). Through the written names of the building found in , it can be assumed that the name of the square pond with Seokgasan was Taehwaji or Jeongwudang, and the name of the Seokgasan was Sogeumgang(小金剛) or Sobangjang(小方丈). The names correspond to the names of the Seokgasan of Gukdam, which was Yangsimdae(養心臺) and Bongnaesan(蓬萊山). By means of the corresponding names, it can be inferred that the relations between the spaces were intended. was originally created as 'a manor painting(莊園圖)', led by the 15th generation of the Ju family who moved into Chirwon-ri, Haman. The painting describes not only the back garden but also the external scenery, thus it provides important evidences for understanding Mugi-YeonDang and its nearby landscape, and is helpful to its maintenance and restoration.

A Study on the Meaning and Spatial Characteristics of the Chinese Zhuozhengyuan from the Tablets (편액을 통해 본 중국 졸정원의 의미와 공간 특성)

  • Ham, Kwang-Min;Son, Yong-Hoon;Li, Shu-Hua
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.35 no.4
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    • pp.98-109
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    • 2017
  • The results of this study attempting to graft to the space by cognizing and categorizing the characteristic of the under-toned private property to the tablets of the Zhuozhengyuan are as follows. The tablet of Zhuozhengyuan was typed into three groups. In the A group, the frequency of artificial elements including the top, ship, and head was high, and the main emphasis was on the elegance and integrity spirit that the Sunbi(classical scholar) had to have. It has a characteristic of good architects such as pavilion and Nu(樓) is included and as it is adjacent to the water surface the one side of the building is integrated to the water surface. The B group is characterized mainly by the fact that the scenery is portrayed through the climatic factors including rain, wind, and snow, or the scene atmosphere and it is located at the top of the summit which is good for viewing the scenery. In the C group, plant elements such as lotus, magnolia, plum, and bamboo appeared frequently, and various buildings such as pavilion, Kwan(館), Gak(閣) and Dang(堂) belong to this structure. The structure has the characteristic of integrating directly with the water surface or putting the terrace between and scattering throughout the whole garden. Furthermore, this study identified area characteristics based on the frequency of the tablet type. In the west area, Group A is mostly distributed and the humor and concept implied in the tablet, combined with the shape and location of the scenery, viewpoint of the viewer, and the composition of the landscape, improved the orderliness of the space, which led to expand the scope of the enjoyment to the entire space. Meanwhile, in the middle area, tablets of Group C are mostly distributed, and the unique characteristics and shapes of the woody plants that were used as the name of the tablet were connected with various buildings including pavilion, Dang, Kuan, and Gak, improving the unique identity of the space and forming connection with the world of ideas through unity and independence.

Sentiment analysis on movie review through building modified sentiment dictionary by movie genre (영역별 맞춤형 감성사전 구축을 통한 영화리뷰 감성분석)

  • Lee, Sang Hoon;Cui, Jing;Kim, Jong Woo
    • Journal of Intelligence and Information Systems
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    • v.22 no.2
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    • pp.97-113
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    • 2016
  • Due to the growth of internet data and the rapid development of internet technology, "big data" analysis is actively conducted to analyze enormous data for various purposes. Especially in recent years, a number of studies have been performed on the applications of text mining techniques in order to overcome the limitations of existing structured data analysis. Various studies on sentiment analysis, the part of text mining techniques, are actively studied to score opinions based on the distribution of polarity of words in documents. Usually, the sentiment analysis uses sentiment dictionary contains positivity and negativity of vocabularies. As a part of such studies, this study tries to construct sentiment dictionary which is customized to specific data domain. Using a common sentiment dictionary for sentiment analysis without considering data domain characteristic cannot reflect contextual expression only used in the specific data domain. So, we can expect using a modified sentiment dictionary customized to data domain can lead the improvement of sentiment analysis efficiency. Therefore, this study aims to suggest a way to construct customized dictionary to reflect characteristics of data domain. Especially, in this study, movie review data are divided by genre and construct genre-customized dictionaries. The performance of customized dictionary in sentiment analysis is compared with a common sentiment dictionary. In this study, IMDb data are chosen as the subject of analysis, and movie reviews are categorized by genre. Six genres in IMDb, 'action', 'animation', 'comedy', 'drama', 'horror', and 'sci-fi' are selected. Five highest ranking movies and five lowest ranking movies per genre are selected as training data set and two years' movie data from 2012 September 2012 to June 2014 are collected as test data set. Using SO-PMI (Semantic Orientation from Point-wise Mutual Information) technique, we build customized sentiment dictionary per genre and compare prediction accuracy on review rating. As a result of the analysis, the prediction using customized dictionaries improves prediction accuracy. The performance improvement is 2.82% in overall and is statistical significant. Especially, the customized dictionary on 'sci-fi' leads the highest accuracy improvement among six genres. Even though this study shows the usefulness of customized dictionaries in sentiment analysis, further studies are required to generalize the results. In this study, we only consider adjectives as additional terms in customized sentiment dictionary. Other part of text such as verb and adverb can be considered to improve sentiment analysis performance. Also, we need to apply customized sentiment dictionary to other domain such as product reviews.

Evaluation of satellite-based evapotranspiration and soil moisture data applicability in Jeju Island (제주도에서의 위성기반 증발산량 및 토양수분 적용성 평가)

  • Jeon, Hyunho;Cho, Sungkeun;Chung, Il-Moon;Choi, Minha
    • Journal of Korea Water Resources Association
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    • v.54 no.10
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    • pp.835-848
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    • 2021
  • In Jeju Island which has peculiarity for its geological features and hydrology system, hydrological factor analysis for the effective water management is necessary. Because in-situ hydro-meteorological data is affected by surrounding environment, the in-situ dataset could not be the spatially representative for the study area. For this reason, remote sensing data may be used to overcome the limit of the in-situ data. In this study, applicability assessment of MOD16 evapotranspiration data, Globas Land Data Assimilation System (GLDAS) based evapotranspiration/soil moisture data, and Advanced SCATterometer (ASCAT) soil moisture product which were evaluated their applicability on other study areas was conducted. In the case of evapotranspiration, comparison with total precipitation and flux-tower based evapotranspiration were conducted. And for soil moisture, 6 in-situ data and ASCAT soil moisture product were compared on each site. As a result, 57% of annual precipitation was calculated as evapotranspiration, and the correlation coefficient between MOD16 evapotranspiration and GLDAS evapotranspiration was 0.759, which was a robust value. The correlation coefficient was 0.434, indicating a relatively low fit. In the case of soil moisture, in the case of the GLDAS data, the RMSE value was less than 0.05 at all sites compared to the in-situ data, and a statistically significant result was obtained as a result of the significance test of the correlation coefficient. However, for satellite data, RMSE over than 0.05 were found at Wolgak and there was no correlation at Sehwa and Handong points. It is judged that the above results are due to insufficient quality control and spatial representation of the evapotranspiration and soil moisture sensors installed in Jeju Island. It is estimated as the error that appears when adjacent to the coast. Through this study, the necessity of improving the existing ground observation data of hydrometeorological factors is emphasized.

A Study on the Space Organization and Garden Language of Mongsimjae in Namwon (남원 몽심재(夢心齋)의 정원구성과 조형언어 해석)

  • Rho, Jae-hyun;Choi, Yung-hyun;Shin, Sang-sup
    • Korean Journal of Heritage: History & Science
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    • v.47 no.1
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    • pp.32-45
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    • 2014
  • In this study, the characteristics of Mongsimjae in Namwon-si, Jeollabuk-do have been researched focusing on the writings engraved in huge stones and rocks of pavilion standing beside a lotus pond and its formative languages in the garden has been interpreted as follows. Name of pavilion(堂號) Mongsimjae(夢心齋) includes a classical scholar's spirit, refusing to serve two kings and homecoming after resignation from a government office(歸去來) of Songam(松菴) Park Moonsu(朴門壽), an ancestor who has brought to the Juksan(竹山) Park's family again. A pavilion standing beside a lotus pond(蓮塘) built in the reception garden is a gardening facility symbolizing 'Yeondang(蓮堂)' Park Dongsik(朴東式) who built Mongsimjae. The bamboo hill connected to the backyard seems to be relevant to 'Juksan', the family clan of Mongsimjae's owner and this kinds of intention can be found in the bamboos in the outer garden naturally led to inside the garden through the flower beds. The purpose for the western arrangement of the main building and gate contrary to the 'chukjwamihyaug'(丑坐未向; a direction toward to the south-southwest) of the prospect of Sarangchae(guesthouse) is interpreted to naturally attract people's eyes to the pavilion standing beside a lotus pond and to mitigate the sense of closure resulting from the huge stones located in the reception garden. Also the writing engraved in the three huge stones, 'Jonsimdae(存心臺)', implies that it is a place where was selected with heart by Juksan Park family who settled down in Homsil, Namwon after 'Haengchon(杏村) Park Jaryang(朴子良)' in Yiphyangjo(入鄕祖), Namwon and 'Jeongwa(靖窩)' is interpreted as a signature representing that it is the most comfortable house where Jeongwa Park Haechang(朴海昌: 1876~1933), the third owner of Mongsimjae, has lived. The pavilion standing beside a lotus pond of the 'Bangjibangdo(方池方島; square pond and square island)' type has no lotus for now and waterside cornerstones roughly piled with broken stones naturally mitigate the slope. There are two water inflows gathering rainwater in the reception garden other than the water inflow of valley and the upper-side water inflow was built using a high waterfall method. The middle island cut into a square was designed to use in two ways, as 'island' or 'steppingstone', according to the water level and the old name of the pavilion standing beside a lotus pond was revealed as 'Cheonundam(天雲潭)' from the engraved writing located in the side of the middle island. In addition, 'Imni(臨履)', engraved writing in the finishing stone of waterside by citing a line of 'Sigyeong(詩經)', implies 'Be a upright classical scholar who pays close attention to one's own behaviors' and 'Jeongchuk(渟?)' is interpreted as a message that desires the eternal staying of the Juksan Park family's wealth. Ultimately, the writings engraved in the huge stones and rocks of the pavilion standing beside a lotus pond are interpreted as a symbol language that wishes the heaven protects and maintains the wealth of the Juksan Park family who is the owner of Mongsimjae.

A Study on Dongbu Hamchunwon in Hanyang during the Joseon Dynasty (조선시대 한양 동부(東部) 함춘원(含春苑)에 관한 연구)

  • Oh, Jun-Young;Kim, Young-Mo
    • Korean Journal of Heritage: History & Science
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    • v.50 no.3
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    • pp.110-125
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    • 2017
  • The purpose of this study is to investigate the constructional facts and the operational features of Hamchunwon(含春苑), a wonyu(苑?, a royal garden) constructed in Dongbu(Eastern District) of the capital city of Hanyang. As the living quarters of the queen dowagers were scheduled for relocation after the construction of Changgyeonggung Palace(昌慶宮) during the reign of King Seongjong(成宗), it is presumed that the screening tree planting project discussed around tongmangcheo(通望處, a place allowing open view) was the original form of Dongbu Hamchunwon. Dongbu Hamchunwon was a longitudinal royal garden built in the area across the section from Wolgeunmun Gate(月覲門) to Seoninmun Gate(宣仁門), which were both attached to the east side walls of Changgyeonggung Palace. The area corresponds to the west side area of the newly built main building of Seoul National University Hospital today. During the Joseon Dynasty, only royal gardens built within a palace were referred to as geumwon(禁苑, a palace garden). But Dongbu Hamchunwon which was built outside a palace was recognized as a symbolic and hierarchical space comparable to geumwon. The site location of Donbu Hamchunwon was an important place that corresponded to Naecheongnyong(內靑龍) according to Hanyang's geomancy, and large-scale public works were prohibited in order to protect the vein of Naecheongnyong. During the reign of King Injo(仁祖), part of Dongbu Hamchunwon was partitioned as a ranch. The area around the ranch was called Madongsan(馬東山) and Bangmawon(放馬苑) and was an open space used for rest and pleasure (amusement). In the early days of Hamchunwon's construction, fast growing trees were planted to screen the view to Changgyeonggung Palace. However, after the construction of Gyeongmogung Shrine(景慕宮), a broad scale tree planting project was undertaken to complement Naecheongnyong's vapor of the earth. In particular, after the construction of Yugeunmum Gate(?覲門) and Yucheommun Gate(?瞻門) during the reign of King Jeongjo(正祖), Dongbu Hamchunwon functioned as a key point on the King's progress for paying respects to the ancestors, which followed the route of Palace(Changgyeonggung)-Wonyu(Hamchunwon)-Ancestral Shrine(Gyeongmogung).

Preparation and Characterization of Bamboo-based Activated Carbon by Phosphoric Acid and Steam Activation (인산 및 수증기 활성화에 의한 대나무 활성탄 제조 및 특성 연구)

  • Park, Jeong-Woo;Ly, Hoang Vu;Oh, Changho;Kim, Seung-Soo
    • Clean Technology
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    • v.25 no.2
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    • pp.129-139
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    • 2019
  • Bamboo is an evergreen perennial plant, and it is known as one of the most productive and fastest-growing plants in the world. It grows quickly in moderate climates with only moderate water and fertilizer. Traditionally in Asia, bamboo is used for building materials, as a food source, and as versatile raw materials. Bamboo as a biomass feedstock can be transformed to prepare activated carbon using the thermal treatment of pyrolysis. The effect of process variables such as carbonization temperature, activation temperature, activation time, the amount of steam, and the mixing ratio of phosphoric acid and bamboo were systematically investigated to optimize the preparation conditions. Steam activation was proceeded after carbonization with a vapor flow rate of $0.8{\sim}1.8mL-H_2O\;g-char^{-1}\;h^{-1}$ and activation time of 1 ~ 3 h at $700{\sim}900^{\circ}C$. Carbon yield and surface area reached 2.04 ~ 20.59 wt% and $499.17{\sim}1074.04m^2\;g^{-1}$, respectively, with a steam flow rate of $1.4mL-H_2O\;g-char^{-1}\;h^{-1}$ for 2 h. Also, the carbon yield and surface area were 24.67 wt% and $1389.59m^2\;g^{-1}$, respectively, when the bamboo and phosphoric acid were mixed in a 1:1 weight ratio ($700^{\circ}C$, 2 h, $1.4mL-H_2O\;g-char^{-1}\;h^{-1}$). The adsorption of methylene blue into the bamboo activated carbon was studied based on pseudo first order and second order kinetics models. The adsorption kinetics were found to follow the pseudo second order model, which is governed by chemisorption.

Examining the Relationship Among Restaurant Brand Relationship Quality, Attribution, and Emotional Response After Service Failure Experience (서비스 실패 경험 후 레스토랑 브랜드 품질, 귀인 및 감정반응 관계분석)

  • Jang, Gi-Hwa;Song, Soo-Ik;Oh, Sung-Cheon
    • Journal of the Korean Applied Science and Technology
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    • v.35 no.4
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    • pp.1120-1133
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    • 2018
  • The purpose of this study is to validate the failure attribution factors affecting emotional changes after a failed service by local restaurant users, and the relapse effects of the perceived failure of a customer's brand relationship. In this study, the implications of this study can be divided into the null theory and the homogenous theory, in which the study of the relationship between individual belief that influences the null theory and the post-gender emotional response is minimal. The independence of the crash response (angerous VS compassion) has been equally validated as building a belief-gathering-emotion three-step model. First, emotional BRQ (intimate and love) has a reduction effect on controllable geeks, and behavioral BRQ (relative existence) has an extended effect on controllable geeks. From a management perspective, restaurant managers should be less aware of the repeatability of a customer's service failure and call for customer sympathy. Integratedly, restaurant managers must control the customer's perception of service failure and restore the impact of the customer's BRQ on emotional reactions. A variety of service recovery measures should be established and the cerumen should be controlled. In addition, since BRQs have different effects on anger and sympathy (extended VS), different service failure recovery plans should be presented depending on the characteristics of the customer BRQ. For example, measures such as monetary compensation or fair dealing, emotional distribution to close and loving customers, and persuasion of reciprocal benefits to interdependent customers should be developed according to circumstances. This study explored the effectiveness of the geeks after a service failure and has limitations that do not take into account the various regulatory factors in the BRQ-return-Empression process. Thus, in further studies, the effects of adjusting service failure strength should be considered and a more complete model should be built.