• Korean Chemical Engineering Research
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• v.53 no.6
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• pp.792-797
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• 2015

Graphene has a wide spectrum on its application field due to various and excellent physical properties. However, it is very difficult to apply that graphene exists as lump or fold condition in general organic solvents. Besides, graphene was difficult to maintain as uniform condition due to chemical inert and distributions with various size and shapes. Therefore, this study was focused to study dispersion and modifying methods of aggregated graphene. The dispersion methods contain as follow: i) physical milling using glass bead, ii) co-treatment of glass bead and ultrasonic waves, iii) dispersion in organic solvents, iv) modifying with dry-ice. Milling using glass bead with size 2.5 mm was effective to be size decrease of 36.4% in comparison with control group. Mixed treatment of glass bead (size 2.5 mm) and ultrasonic waves (225W, 10 min) showed relative size decrease of 76%, suggesting that the size decrease depends on the size of glass bead, intensity of ultrasonic waves and treatment time. Solvents of Ethyl acetate (EA) and Isoprophyl alcohol (IPA) were used in order to improve dispersion by modifying surface of graphene. IPA of them showed a favorable dispersion with more -CO functional groups in the FT-IR analysis. On the other hand, the oxygen content of graphene surface modified by dry-ice was highly increased from 0.8 to 4.9%. From the results, it was decided that the favorable dispersion state for a long time was obtained under the condition of -CO functional group increase in IPA solvent.

• Journal of the Korean Institute of Landscape Architecture
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• v.41 no.6
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• pp.29-42
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• 2013

The purpose of this study was to derive selection attribute of fishing experience villages, and to analyze the importance and performance on targeting experts and experienced tourists. Consequently, it could suggest implications for the guideline and the evaluation criteria of making fishing experience villages for the revitalization of eco experience tourism. Therefore, in this study, literature investigation and IPA analysis were used by Microsoft Office Excel 2010, SPSS 20.0. As a result, the 'variety of local foods and specialties' was the most urgent attribute to require intensive management strategy. And it is recommended to improvement about 'attributes related residents' because it were insensitived on the recognition by users. Satisfaction of 'appropriateness of coast' was the lowest, but the efficiency was quite high. Finally, not only 'the area of control' but also 'the area of influence' should be reviewed as an important aspects on developing the fishing experience village. The significance of this study is to derive selection attributes of making fishing experience villages for revitalization of eco experience tourism, and to suggest strategy directions based on IPA analysis result by experts and experienced tourists. But in this study, the site was limited to Gyeonggi-do, so it is recommended to expand further.

• Korean Journal of Environment and Ecology
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• v.20 no.2
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• pp.159-169
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• 2006

Interpretive sign is a communication medium that is often used in self-guided interpretation. Understanding interpretive signs and their users is important to maximize the effectiveness of interpretation. This study evaluated design attributes of interpretive signs by visitor's personal characteristics and visiting patterns using Importance-Performance Analysis(IPA). Data were collected from August to September of 2003 at the self-guided trail in Naejangsan National Park, Korea. Visitors using the trail participated in a questionnaire survey, and a total of 276 subiects was used for data analysis. The IPA results showed that female(23.3%) than male(13.3%), low age group(43.3%) than middle(0.0%) and high age group(0.0%), higher education group(36.7%) than lower education group(0.0%), medium size group(33.3%) than large(10.0%) or small group(16.7%), 'with child' group(66.7%) than 'without child' group(20.0%) rated higher importance and lower performance on more design attributes of the interpretive signs. These groups also showed higher rate of 'Concentrate Here(CH)' attributes that require urgent improvement. The 'with child' group showed the especially high rate of 'CH' attributes. The results suggest that interpretive signs need to be designed considering diverse user groups. It is also necessary to develop some standardized items of the sign design attributes for more efficient and reliable implementation of IPA and other evaluative works.

• Journal of Digital Convergence
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• v.18 no.4
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• pp.55-65
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• 2020

The factors for service quality improvement of frozen and refrigerated warehouses are derived and the differences in perception about service quality improvement between shippers and operators of frozen and refrigerated cargos are analyzed. The objective of this study is to propose quality improvement measures for frozen and refrigerated cargo services using the importance-performance analysis (IPA). As a result, 15 analysis factors were derived. It was found through independent sample t-test that there is no difference in perception about quality improvement between shippers and operators. Furthermore, four top priority investment areas were derived from the IPA: maintaining temperature and humidity, securing variable storage space, on-time stocking and releasing, and providing information service. Meanwhile, inventory management service ability, on-time stocking and releasing, and reliable cargo storage ability needed urgent improvement. This study has industrial implications in that it proposes practical improvement measures for service quality improvement.

• Tuberculosis and Respiratory Diseases
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• v.84 no.4
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• pp.326-332
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• 2021

Background: The association of invasive tracheobronchial aspergillosis (ITBA) with invasive pulmonary aspergillosis (IPA) is not well established. We aimed to compare clinical characteristics between patients who exhibited ITBA with IPA and those who exhibited isolated ITBA (iITBA). Additionally, the usefulness of serum or bronchial galactomannan (GM) tests in diagnosing ITBA was evaluated. Methods: This retrospective single-center case-control study was conducted over a period of 4 years. Fifteen patients were enrolled after confirming the presence of ITBA using bronchoscopy-guided biopsy (iITBA, 7 vs. ITBA+IPA, 8). Clinical characteristics of patients and results obtained from serum or bronchial GM tests were compared between the two groups. Mortality was assessed using data collected from a 6-month follow-up period. Results: The ITBA+IPA group showed a higher prevalence of hematologic malignancy (75% vs. 14%, p=0.029), a greater number of patients with multiple bronchial ulcers (75% vs. 14%, p=0.029), lower platelet counts (63,000/μL vs. 229,000/μL, p<0.001), and a mortality rate which was significantly higher (63% vs. 0%, p=0.026) than the iITBA group. In the ITBA+IPA group, 57% of patients tested positive according to the serum GM assay, whereas in the iITBA group, all patients tested negative (p=0.070). The bronchial GM level was high in both groups, but there was no significant difference between them. Conclusion: Patients with ITBA+IPA had a greater number of hematologic malignancies with lower platelet counts and a poorer prognosis than patients diagnosed with iITBA. Findings obtained from bronchoscopy and bronchial GM tests were more useful in diagnosing ITBA than the serum GM test results.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.44 no.3
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• pp.176-191
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• 2021

Non-face-to-face lectures have become a necessity rather than an option since COVID-19, and in order to improve the quality of university education, it is necessary to explore the properties of non-face-to-face lectures and make active efforts to improve them. This study, focusing on this, aims to provide basic data necessary for decision-making for non-face-to-face lecture design by analyzing the relative importance and execution satisfaction of non-face-to-face lecture attributes for professors and students. Based on previous research, a questionnaire was constructed by deriving 4 factors from 1st layer and 17 from 2nd layer attributes of non-face-to-face lectures. A total of 180 valid samples were used for analysis, including 60 professors and 120 students. The importance of the non-face-to-face lecture properties was calculated by obtaining the weights for each stratified element through AHP(Analytic Hierachy Process) analysis, and performance satisfaction was calculated through statistical analysis based on the Likert 5-point scale. As a result of the AHP analysis, both the professor group and the student group had the same priority for the first tier factors, but there was a difference in the priorities between the second tier factors, so it seems necessary to discuss this. As a result of the IPA(Importance Performance Analysis) analysis, the professor group selected the level of interaction as an area to focus on, and it was confirmed that research and investment in teaching methods for smooth interaction are necessary. The student group was able to confirm that it is urgent to improve and invest in the current situation so that the system can be operated stably by selecting the system stability. This study uses AHP analysis for professors and students groups to derive relative importance and priority, and calculates the IPA matrix using IPA analysis to establish the basis for decision-making on future face-to-face and non-face-to-face lecture design and revision. It is meaningful that it was presented.

• 재활복지
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• v.22 no.1
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• pp.51-86
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• 2018

The study was conducted to examine the characteristics of case management in psychiatric rehabilitation facilities. The purpose of this study is to analyze the importance and performance of case management activities, and 114 cases managers in the psychiatric rehabilitation facilities in Seoul participated in the study. The study analysed the importance and performance of each case management through IPA and Paired T-test. As a result of the study, Assessment stage showed the highest performance and importance, and the performance was conducted as much as the importance. Except assessment, performance in all stages were significant lower than the importance. IPA analysis showed that most case management activities belonged to the quadrant I(high importance-high performance) and the quadrant III (low importance-low performance), but the T-test analysis showed lower performance than importance. Participation of Service users and Cooperation of community resource were lower than those of importance. Participation of Service users showed high importance and performance, but performance was relatively lower than importance. On the other hand, cooperation of community resource was low in overall importance and performance, moreover, performance was very low. It is considered that various efforts should be made to activate them.

• The Journal of the Korea Contents Association
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• v.21 no.1
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• pp.417-425
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• 2021

This study was conducted to evaluate the characteristics of major selection of college students majoring in culinary. By conducting an Importance-Performance Analysis(IPA) through students who are currently majoring in a culinary major, it is intended to increase student satisfaction, student loyalty, the enrollment rate and to present the direction the college should pursue. The questionnaire was conducted for 4 weeks from June 22, 2020 to July 19, 2020, the results are as follows. As a result of the t-test (paired sample t-test) for 23 attributes, the average value of importance was 4.0765, the average value of satisfaction was 3.5091, showing high importance, the attributes considered important by item were 'educational facilities (4.50)', 'school welfare (4.50)', the attributes having the highest satisfaction with experience after selecting a major were 'aptitude and conformity (3.94)', 'future hope and concordance (3.91)'. The IPA analysis results on the major selection attributes of college students majoring in culinary are as follows. First, In the first quadrant, 11 attributes including 'aptitude and conformity' appeared, Second, In the second quadrant, 5 attributes including 'employment support' appeared. Third, In the third quadrant, 5 attributes including 'college scholastic ability score' appeared, Finally, In the fourth quadrant, 2 attributes including 'experience in major field' appeared.

• Journal of the Korea Convergence Society
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• v.13 no.3
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• pp.309-315
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• 2022

The purpose of this study is to analyze the correlation between importance and satisfaction of beauty contest using IPA(Importance-Performance Analysis) by deriving the quality factors of contest for revitalize beauty contest. For the study, a survey was conducted on participants with experience participating in beauty contest, and the collected data were analyzed using a response sample t-test and a PIA matrix. The results are as follows. First, there was a difference in importance and satisfaction as the average of importance was high. Second, in the first quadrant of the IPA matrix, contents related to contest assignment were mainly shown. This was analyzed as an effective factor that can improve the quality of the competition. Third, in the second quadrant, factors related to contest review were distributed. Accordingly, measures are required to increase the expertise and transparency of review. Fourth, in the third quadrant, the contents of the contest operation are mainly shown, and the satisfaction level is low, but supplementing it will have an improvement effect. Fifth, in the fourth quadrant, the satisfaction of the ability improvement item was high, which is analyzed that the contest experience affects the improvement of individual skills. Through this, it is significant to be used as basic data to establish a plan for revitalizing beauty contest.

• Journal of the Korean Institute of Landscape Architecture
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• v.50 no.2
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• pp.89-101
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• 2022

The study was conducted in Erhe Park, a neighborhood park in Dali City, China, to derive the influence of environmental factors in the park on the elderly's satisfaction and to analyze the satisfaction in order to provide improvement recommendations. First, the evaluation indicators were selected, by referencing previous research into the elderly's evaluation of external spatial environments and the influence of various factors was determined from the questionnaire and factor analysis. Second, a fuzzy comprehensive evaluation was conducted to understand the satisfaction of the elderly, and then an Importance-Performance Analysis(IPA) analysis was conducted to develop improvement recommendations. Results of the factor analysis showed that park's environmental factors were grouped into four categories: facility suitability and comfort, safety and convenience of use, natural environment comfort, and parkway convenience. Based on this, the overall satisfaction rating for the environmental factors in Erhe Park was between satisfactory and average. The natural environment comfort was rated satisfactory, the facility suitability and comfort, and convenience and safety were rated average, and parkway convenience was rated near to satisfaction. The IPA analysis revealed that the suitability of rest facilities, suitability of convenience facilities, facility management status, safety of entrances and exits, and nighttime lighting facilities were items of high importance but low satisfaction that needed to be improved. The results of this study can be utilized as a guide for future building or readjustment of senior-friendly parks, and they are critical for increasing senior-friendly park satisfaction.