• Title/Summary/Keyword: 한국지지

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Oxidative Desulfurization of Marine Diesel Using Keggin Type Heteropoly Acid Catalysts (Keggin형 헤테로폴리산 촉매를 이용한 선박용 경유의 산화 탈황)

  • Oh, Hyeonwoo;Woo, Hee Chul
    • Clean Technology
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    • v.25 no.1
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    • pp.91-97
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    • 2019
  • Oxidative desulfurization (ODS) has received much attention in recent years because refractory sulfur compounds such as dibenzothiophenes can be oxidized selectively to their corresponding sulfoxides and sulfones, and these products can be removed by extraction and adsorption. In this work, The oxidative desulfurization of marine diesel fuel was performed in a batch reactor with hydrogen peroxide ($H_2O_2$) in the presence of various supported heteropoly acid catalysts. The catalysts were characterized by XRD, XRF, XPS and nitrogen adsorption isotherm techniques. Based on the sulfur removal efficiency of promising silica supported heteropoly acid catalysts, the ranking of catalytic activity was: $30\;H_3PW_{12}/SiO_2$ > $30\;H_3PMo_{12}/SiO_2$ > $30\;H_4SiW_{12}/SiO_2$, which appears to be related with their intrinsic acid strength. The $30\;H_3PW_{12}/SiO_2$ catalyst showed the highest initial sulfur removal efficiency of about 66% under reaction conditions of $30^{\circ}C$, $0.025g\;mL^{-1}$ (cat./oil), 1 h reaction time. However, through the recycle test of the $H_3PW_{12}/SiO_2$ catalyst, significant deactivation was observed, which was attributed to the elution of the active component $H_3PW_{12}$. By introducing cesium cation ($Cs^+$) into the $H_3PW_{12}/SiO_2$ catalyst, the stability of the catalyst was improved with changing the solubility, and the $Cs^+$ ion exchanged catalyst could be recycled for at least five times without severe elution.

Decomposition of Eco-friendly Liquid Propellants over Platinum/Hexaaluminate Pellet Catalysts (백금/헥사알루미네이트 펠렛 촉매를 이용한 친환경 액체 추진제 분해)

  • Jo, Hyeonmin;You, Dalsan;Kim, Munjeong;Woo, Jaegyu;Jung, Kyeong Youl;Jo, Young Min;Jeon, Jong-Ki
    • Clean Technology
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    • v.24 no.4
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    • pp.371-379
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    • 2018
  • The objective of this study is to develop a platinum/hexaaluminate pellet catalyst for the decomposition of eco-friendly liquid propellant. Pellet catalysts using hexaaluminate prepared by ultrasonic spray pyrolysis as a support and platinum as an active metal were prepared by two methods. In the case of the pellet catalyst formed by loading the platinum precursor onto the hexaaluminate powder and then adding the binder (M1 method catalyst), the mesopores were well developed in the catalyst after calcination at $550^{\circ}C$. However, when this catalyst was calcined at $1,200^{\circ}C$, the mesopores almost collapsed and only a few macropores existed. On the other hand, in the case of a catalyst in which platinum was supported on pellets after the pellet was produced by extrusion of hexaaluminate (M2 method catalyst), the surface area and the mesopores were well maintained even after calcination at $1,200^{\circ}C$. Also, the catalyst prepared by the M2 method showed better heat resistance in terms of platinum dispersion. The effects of preparation method and calcination temperature of Pt/hexaaluminate pellet catalysts on the decomposition of liquid propellant composed mainly of ammonium dinitramide (ADN) or hydroxyl ammonium nitrate (HAN) were investigated. It was confirmed that the decomposition onset temperature during the decomposition of ADN- or HAN- based liquid propellant could be reduced significantly by using Pt/hexaaluminate pellet catalysts. Especially, in the case of the catalyst prepared by the M2 method, the decomposition onset temperature did not show a large change even when the calcination temperature was raised at $1,200^{\circ}C$. Therefore, it was confirmed that Pt/ hexaaluminate pellet catalyst prepared by M2 method has heat resistance and potential as a catalyst for the decomposition of the eco-friendly liquid propellants.

Essay on the Community Archpe ('마을아르페'(Community Archpe) 시론 - 마을 차원의 "책, 기록, 역사 그리고 치유와 창업의 커뮤니티"를 위한 제안-)

  • Lee, Young-Nam
    • The Korean Journal of Archival Studies
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    • no.18
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    • pp.221-254
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    • 2008
  • Community Archpe is . Community Archpe is as close as a kind of a complex of culture space or community center which puts individuals and small community together with culture soil in a central position. For example Community Archpe can include community library, community archive, community historical center, community recovery center, community commencement of an enterprise center, etc. We need small library, archive and historian rather than big scale institution and professional system to take care of culture soil which belongs to an individual and community. Community Archpe is located in coordinates of two intention points. First intention is, a 'Heterogenous Smithy'. Heterogeneity deals with Community Archpe's life. Second intention is, a 'Feminine Smithy'. Community Archpe can be a recovery community when we are in the recovery context, which understand and support a person through archives and history. Then, what can Community Archpe do? First, it can be a new movement of the community. Second, it can also be a centripetal point of classic life. Community Archpe surly locates in the central of Community. Therefore, it will be a cultural literary soil and be a smithy of community history and culture. Thus Community Archpe will change a lot of things on people's life. Community Archpe will be a small happiness to ordinary people, even though it is not a state organ realizing large values.

The strengthening of North Atlantic Deep Water during the late Oligocene based on the benthic foraminiferal species Oridorsalis umbonatus (저서성 유공충 Oridorsalis umbonatus의 산출 상태에 기록된 후기 올리고세 북대서양 심층수의 강화)

  • Lee, Hojun;Jo, Kyoung-nam;Lim, Jaesoo
    • Journal of the Geological Society of Korea
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    • v.54 no.5
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    • pp.489-499
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    • 2018
  • A series of geological events such as the formation of the Antarctic continental ice sheets, the changes in ocean circulation and a mass extinction after the onset of Oligocene has been studied as major concerns by various researches. However, paleoclimatic and paleoceanographic changes during the most period of Oligocene since the Eocene-Oligocene transition (EOT) still remains unclear. Especially, although the late Oligocene warming (LOW) has been assessed as the largest period in the paleoceanographic changes, the detailed understanding on the changed components is very low. The purpose of this study is the reconstruction of the paleoceanographic history during the late Oligocene using core sediments from IODP Expedition 342 Site U1406 performed in J-Anomaly Ridge in North Atlantic. Because North Atlantic deep water (NADW) has flowed southward through the study area since the early Oligocene, this area has been considered to an important location for studies on the changes of NADW. The core sediment analyzed in this study were deposited from about 26.0 to 26.5 Ma as evidenced by both of onboard and shore-based paleomagnetic data, and this is corresponded to the earliest period of LOW. The sediment profile can be divided into three Units (Unit 1, 2 & 3) based on the changes in both of total number and test size of Oridorsalis umbonatus as well as grain size data of clastic sediments. Unit 2 represents largest values in these three data. Because the total number, test size of O. umbonatus and grain size can be proxy records on the oxygen concentration and circulation intensity of deep water, we interpreted that Unit 2 had been deposited during the period of relatively strengthened NADW. Previous Cibicidoides spp. stable isotope results from the low latitude region of the North Atlantic also support our interpretation that is the intensified formation of NADW during the identical period. In conclusion, our results present a new evidence for the previous ideas that the causes on LOW are directly related to the changes in NADW.

Illness Experiences and Palliative Care Needs in Community Dwelling Persons with Cardiometabolic Diseases (심혈관대사질환이 있는 지역사회 거주 환자의 질환경험 및 완화의료 요구)

  • Cha, EunSeok;Lee, JaeHwan;Lee, KangWook;Hwang, Yujin
    • Journal of Hospice and Palliative Care
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    • v.22 no.1
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    • pp.8-18
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    • 2019
  • Purpose: This study was conducted to better understand the illness experiences and palliative care needs in community-dwelling persons with cardiometabolic diseases. Methods: This qualitative descriptive study was conducted with 11 patients (and three family members) among 28 patients contacted. Interviews were led by the principal investigator in her office or at participants' home depending on their preference. All interviews were digitally recorded and transcribed by a research assistant. The interviews were analyzed by two independent researchers using a conventional method. Results: Participants' ages ranged from 42 to 82 years (nine men and two women). Three themes were identified: (1) same disease, but different illness experiences; (2) I am in charge of my disease(s); (3) preparation for disease progression. Participants were informed of the name of their disease when they were diagnosed, but not provided with explanation of the diagnosis or meant or how to do self-care to delay the disease progression, which increased the feelings of uncertainty, hopelessness and anxiety. Taking medication was considered to be the primary treatment option and self-care a supplemental one. Advanced care plans were considered when they felt the progression of their disease(s) while refraining from sharing it with their family or health care professionals to save their concerns. All participants were willing to withhold life-sustaining treatment without making any preparation in writing. Conclusion: Education on self-care and advanced care planning should be provided to community-dwelling persons with cardiometabolic diseases. A patient-centered education program needs to be developed for this population.

Comparison between the biomass and habitat suitability index(HSI) of marine forest forming seaweeds (바다숲 조성 해조류의 생물량과 서식지적합지수 비교)

  • Hwang, Sung Il;Shin, Bong Kyun;Kwak, Yong Sung;Choi, Han Gil
    • Korean Journal of Environmental Biology
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    • v.39 no.1
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    • pp.46-54
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    • 2021
  • The seasonal and vertical biomass of marine forest seaweeds were examined to select a suitable species at 12 sites of the South Sea in Korea between 2018 and 2019. The Habitat Suitability Index (HSI) was also calculated in terms of biomass for six species (three kelp and three Sargassum species). A total of 16 marine forest-forming species including four kelp and 12 Sargassum species were observed at the 12 sites. The average annual seaweed biomass by season and depth ranged from 843.73-2,925.85 g wet wt. m-2 at the eastern South Sea and from 343.87-4,580.10 g wet wt. m-2 at the western South Sea. In the kelp species, the Ecklonia cava biomass was predominant, followed by E. stolonifera. The macroalgal species with the greatest biomass was Sargassum macrocarpum, followed by S. horneri. The HSI values of E. stolonifera were between 0.76-1.0 at eight sites and those of E. cava were 0.58-0.92 at four sites, indicating that E. stolonifera was more suitable than E. cava. In the HSI values of the Sargassum species, S. horneri ranged between 0.84-1.0 at all 12 sites and the S. macrocarpum values were between 0.68-0.99. The results indicate that E. cava and S. macrocarpum were the most suitable for the marine forest construction in terms of the seaweed biomass, and E. stolonifera and S. horneri in terms of the HSI values. Thus, we suggest that seaweed biomass and HSI values should be considered when choosing suitable forest-forming species.

A Study on the Difference of Psychosocial Characteristics and Quality of Life according to the Type of Functional Gastrointestinal Disorder (기능성 위장질환의 종류에 따른 정신사회적 특성 및 삶의 질의 차이에 관한 연구)

  • Park, Seung-Kyu;Lee, Sang-Yeol;Ryu, Han-Seung;Choi, Suck-Chei;Yang, Chan-Mo;Jang, Seung-Ho;Yeom, Dong Han;Lee, Kuy-Haeng
    • Korean Journal of Psychosomatic Medicine
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    • v.29 no.1
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    • pp.58-66
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    • 2021
  • Objectives : The purpose of this study is to compare the psychosocial characteristics of patients diagnosed with functional gastrointestinal disorder (FGID) by classifying them into irritable bowel syndrome (IBS), functional dyspepsia (FD), functional constipation (FC), functional heartburn (FH) groups, and overlap group (two or more functional diseases) and to examine the factors associated with the quality of life (QoL) of patients with FGID. Methods : A total of 144 patients who were diagnosed with FGID were selected as the subjects. The demographical factors were investigated; Korean-Beck Depression Inventory-II (K-BDI-II), Korean-Beck Anxiety Inventory (K-BAI), Korean version of Childhood Trauma Questionnaire (K-CTQ), Multi-dimensional Scale of Perceived Social Support (MSPSS), Korean Version of Connor-Davidson Resilience Scale (K-CD-RISC), and World Health Organization Quality of Life Assessment Instrument Brief Form (WHOQOL-BREF) were used to evaluate the psychosocial factors. Results : TThe overlap group had a significantly higher K-BDI-II score (F=11.09, p<0.001) and K-BAI score (F=8.93, p<0.001) compared to other groups. In childhood trauma, the IBS patients had a difference in emotional neglect (F=2.54, p=0.04) than the FD patients. The QoL of FGID patients had a negative correlation with depression (r=-0.196, p<0.01), anxiety (r=-0.235, p<0.01), and childhood trauma (r=-0.222, p<0.01), and a positive correlation with social support (r=0.512, p<0.01) and resilience (r=0.581, p<0.01). Conclusions : Overlap group had a higher level of depression and anxiety, and the IBS patient group had a higher level of emotional neglect than the FD patient group in terms of childhood trauma.

Life Experience of People Living with HIV/AIDS: rising up from despair (HIV/AIDS 감염인의 감염 이후 삶의 긍정적 경험 : "추락하는 것에는 날개가 있다")

  • Kim, Kyung Mee;Kim, Min-Jung
    • Korean Journal of Social Welfare Studies
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    • v.41 no.1
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    • pp.251-279
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    • 2010
  • In 2009 the Ministry of Health and Society reported a new milestone in longevity among people living with HIV and AIDS (PLWHA): An individual was reported to be living and healthy after 24 years with HIV/AIDS. Today, PLWHA who receive treatment are more likely to die as a result of cancer or cardiovascular diseases than HIV/AIDS. However, in Korea the public association between HIV/AIDS and death remains strong and PLWHA live with the feeling of being discarded. While great advances have been made in the treatment of HIV/AIDS, understanding of life with HIV/AIDS is just beginning. This study describes the life experiences of PLWHA after being diagnosed with HIV/AIDS. Phenomenological methods were used to analyze the transcripts of semi-structured interviews with six PLWHA. Time is a constant factor in the life experiences of PLWHA. After being diagnosed, participants were shocked, feeling as though the world was caving in and they were living with a time bomb. Compulsory disclosure left PLWHA with a feeling of disconnection from the world. Participants were fired from their jobs, resulting in poverty, isolation and a sense that they were simply waiting to die. However, health professionals informed participants that HIV/AIDS is a manageable illness. With time, PLWHA came to understand HIV/AIDS differently. In accepting their HIV infection, PLWHA created a new sense of meaning in their lives. To be honest to their loved ones and true to their own identity, PLWHA worked to "come out." The experience of coming out helped them to accept themselves as they were and understand their own strength. The most important influence on their treatment, and living with HIV/AIDS generally, was obtaining correct information about HIV/AIDS from health professionals. After accepting that they were living with HIV/AIDS, participants were able to look beyond themselves to support those around them, including family members, friends, and others who encouraged them to recognize and feel confident in their own identity.

Evaluation of Physical Properties and Material Characterization for Structural Frame at the Stained Glass Windows to Gongju Jeil Church of the Registered Cultural Heritage in Korea (국가등록문화재 공주제일교회 스테인드글라스 구조재의 재질특성과 물성 평가)

  • Bo Young Park;Hye Ri Yang;Chan Hee Lee
    • Economic and Environmental Geology
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    • v.56 no.1
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    • pp.103-114
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    • 2023
  • The Christian Museum of Gongju Jeil Church was first built in 1931 and was largely damaged during the Korean War, but the walls and chimneys have been preserved. This building has a high architectural values in that the chapel was reconstructed in 1956, and maintains its original form through repair of damaged parts rather than new construction. The stained glass windows were as installed in 1979 and has a great significance in the Dalle de Verre method using lump glass. However, some of the stained glass damaged partially, such as various cracks and splits, and vertical and horizontal cracks in the joint fillers of supporting the colored glass. As the structural materials of the stained glass window, an iron frame and cement mortar filled with it were used, and corrosion of iron, cracking of mortar and granular decomposition appear partially due to weathering. In the joint fillers, the content of Ca and S is very high, indicating that gypsum were used as admixtures, and the gypsums grow in a rhombohedral and forms a bundle, which is investigated to have undergone recrystallization. As a result of modeling the ultrasonic velocity at the joint fillers, the left and right windows at the entrance show relatively weak in the range of 800 to 1,600m/s, and the lower right corner of the altar window and the upper left corner of the center window were also 1,000 to 1,800m/s, showing relatively low physical properties. And gypsums produced during the neutralization of lime mortar were detected in the joint fillers and contaminants on the surface. Such salts may cause damage to the joint material due to freezing and thawing, so appropriate preventive conservation is required. Also, since various damage types are complexly appearing in stained glass window and joint filler, customized conservation treatment should be reviewed through clinical tests.

The Effect of Untact Shopping Customer Experience on Continuous Use Intention through Expectation-Confirmation Model (언택트 쇼핑의 고객경험이 기대일치 모델을 통해 지속이용의도에 미치는 영향)

  • Hong, Suji;Han, Sang-Lin
    • Journal of Service Research and Studies
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    • v.13 no.2
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    • pp.227-245
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    • 2023
  • As offline company and online·mobile startups meet in an untact shopping environment, competition among companies in untact shopping is increasing. In this situation, companies need their own clear strategy to create customer value. In particular, it is very important to focus on 'customer experience' to establish such a strategy in an untact shopping environment. Customer experience refers to all processes in which consumers meet and experience a company or brand at a touch point. In this processes consumers decide whether to continue to use the company and brand. In this situation, it is thought that it will be meaningful for research to examine the customer experience of untact shopping. Therefore, this study aimed to examine the customer experience of untact shopping, which is used by all generations after COVID-19, through experience quality, and to examine the impact on the expectation-confirmation Model of untact shopping. The results of this study are as follows. First, as a result of examining whether interaction quality, information quality, and outcome quality affect expectation-confirmation it was found that all qualities except interaction quality affect expectation matching. Second, as a result of examining whether interaction quality, information quality, and outcome quality affect perceived usefulness, it was found that all qualities except interaction quality had an effect. Next, as a result of applying the expectation confirmation model to the untact shopping environment and examining whether the expectation confirmation has an effect on use satisfaction, it was found that there was a positive effect. As a result of examining whether perceived usefulness affects use satisfaction, it was found to have a positive effect. As a result of examining whether perceived usefulness affects expectation confirmation, it was found that there is a positive effect. Finally, as a result of examining whether perceived usefulness affects the intention to continue using untact shopping, it was found to be positive. Next, as a result of examining the effect of use satisfaction on trust, it was found that there was a positive effect. Finally, as a result of investigating whether trust has an effect on the intention to continue using, it was found that there is a positive effect. Looking at the important results especially, information quality was found to have the greatest influence.