• Clean Technology
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• v.23 no.1
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• pp.54-63
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• 2017

Volatile organic compounds (VOCs) are widely used in both industrial and domestic activities. VOCs are one of the most unpleasant, frequently complaint-rousing factors of pollution around the world. It is now necessary to research and develop an alternative technology that could overcome the problems of the existing odor-control and VOC-eliminating techniques. In this study, essential oil and photocatalytic process was applied in the removal of benzene and toluene, typical VOCs in petrochemistry plant. therefore, this study conducted experiments on the selection of appropriate essential oil, photodegradation, hydroxyl radical generation capacity. The removal efficiency and reaction rate were performed to selecte the type and concentration of essential oil. As a result, removal efficiency of Hinoki Cypress oil was approximately 70% and reaction rate of Hinoki Cypress was high. The results of photolysis experiment, photocatalytic oxidation process showed that the decomposition efficiency of VOCs increased considerably with increasing UV lamp power. In addition, the conversion of VOCs was increased up to $0.1gL^{-1}$ photocatalysts. The hydroxyl radicals measure was performed to determine the ability to generate hydroxyl radicals. The analytical result showed that high $TiO_2$ concentration and lamp power was produced many hydroxyl radical. Experiments of the removal efficiency and reaction rate were performed using essential oil and photooxidation. As a result, the removal efficiency showed that the removal efficiency was increased high temperature and reaction time. The activation energy was calculated from the reaction rate equation at various temperature condition. Activation energy was approximately $18kJmol^{-1}$.

• Journal of the Korea Convergence Society
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• v.8 no.10
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• pp.249-255
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• 2017

The domestic tourism industry mostly relies on quantitative surveys for customer satisfaction. However, customer participation of the questionnaires is extremely low and the improvement of the dissatisfactory factors is not being performed promptly. In this paper, we propose a new topic map system and prove its empirical effectiveness to improve the accuracy of customer feedback information and the efficiency of the analysis process. The topic map system is a system for analyzing large amounts of customer feedback data in real time. It uses text mining and ontology techniques by integrating data collected over a certain period from real-time SNS and quantitative data obtained from existing survey systems. The effect after improving the analyzed factors of dissatisfaction is also a new and innovative evaluation system for monitoring customer satisfaction in real time. The classification based on this integrated data is a classification system that is specific to the product or the customer. According to this classification, it is possible to measure the effect of the recognition and improvement of the complaint factor in real time on the topic map system. This provides a sophisticated prioritization of the improvement factors and enables customer satisfaction quality control as a PDCA feedback system. In addition, the survey period and costs are greatly shortened, and responses can be more precise to the existing survey method. As a practical application, this system is applied to the largest H travel agency in Korea to prove the accuracy and efficiency of the proposed system.

• Journal of Korean society of Dental Hygiene
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• v.3 no.2
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• pp.209-220
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• 2003

The purpose of this study was to examine how clients who visited dental institutions perceived client services, what sorts of client services were provided to them and to what extent they were satisfied with them. It's ultimately meant to seek ways to enhance and enlarge client services. A survey was conducted on 379 residents who used dental institutions in Seoul and Gyeonggi provinces, and the findings of this study were as follows: 1. 64.6 percent of the people investigated weren't aware of client services, and 33.0 percent viewed them as part of medical services. 77.5 percent had grievances about dental institutions they'd ever used. 2. The biggest complaint was that the dental treatments they received weren't covered by the dental insurance. As for how to solve their grievances, the largest group of them told the employees of the dental institutions about their complaints or didn't use them again. When asked whether the dental institutions took any steps to get rid of their grievances, the greatest group replied they had no idea. and the second largest group answered they took no measure. 3. By age and educational level, those who were in their 60s and up and stopped at elementary school were best cognizant of client services. Among client service variables, they were most satisfied with how the employees handled their complaints, and as to overall satisfaction, their willingness to revisit ranked highest. 4. Concerning connections among client service awareness, service variables and overall satisfaction level, their awareness of client services had a positive correlational relationship with every service variable and satisfaction level. Among the service variables, prompt client services and employee attitude were positively correlated to overall satisfaction level, but service procedure, facilities and information services exercised little impact on that. 5. As for what factors affected their content with client services, their client service awareness was identified as one of the important factors to influence their use of dental institutions, the outcome of their visit and their willingness to revisit. The above-mentioned findings suggested that dental institutions should strengthen publicity activities to inform people of client services, and encourage them to express their grievances. In addition, they should take an immediate action to remove their complaints, and try to get a successful feedback to offer higher-quality medical services and customer-oriented services.

• Journal of Energy Engineering
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• v.25 no.4
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• pp.198-206
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• 2016

Fuel economy label will be used as a national indicator in energy management, leading to the development of car technology manufacturer and plays a role in providing consumer vehicle purchase information. But the government's fuel economy label is continued consumer complaint is different and diminishing fuel economy were introduced by the government to measure the exact fuel economy label than resetting the 5-cycle test method in the US for the domestic vehicle standards. Originally two test mode in order to reduce the impact of the sharp increase in the resources required but methods of calculating a measured result value by driving all of the five test mode a variety of environmental conditions and the running pattern is reflected to the fuel economy label (city( FTP-75 mode), highway(HWFET mode)) and using 5-cycle correction formula for calculating a fuel consumption value and the equivalent value to calculate the result of the 5-cycle test. The compensation was calculated expression 30s, 5-Cycle Test Method of vehicles in 2011 was considered necessary to review the existing 5-cycle correction formula for the New Type car due to the recent rapid development of automotive technology. In this study, recent technology is targeting 14 units New Type car applied over the same test method and the existing check test mode specific fuel economy properties and, as a result of analyzing the corrected expression differences that have already been developed with the existing test vehicle resulting large did not show the difference was found to correction formula also not getting the existing fuel correction expression significant effect on the improvement of the current automobile technology as a maximum error of less than 1.5%.

• Journal of Korean Society of Environmental Engineers
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• v.37 no.4
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• pp.240-245
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• 2015

This study aimed to provide the basic data to establish measures for the management of the public toilets and reduction of the offensive odor through the air dilution olfactory method and instrumental analysis about offensive odor dilution rate of public toilets, focusing on the Dong-gu, Daejeon Metropolitan City, Korea. The offensive odor intensities ranged from 10 degree to 669 degrees in the urinal toilets and from 31 to 464 in closet bowl toilets. Meanwhile, toilets that had offensive odor of more than 2.5, of which a civil complaint can be filed, were researched 6 (33%). Offensive odor intensities were different according to the closet bowl toilets of the flush, fermented and conventional methods and the year of their installation, but not according to the area of the toilets. As a result of the instrumental analysis targeting 6 public toilets to identify the offensive odor substance, the maximal concentration of $NH_3$ was 2.04 ppm and the average concentration was 0.67 ppm, but $H_2S$, $CH_3SH$ and $(CH_3)_3N$ were not detected. In the fermented and conventional public toilets were not soaps, air fresheners and wastebaskets. Just 50% of the flush toilets had toilet tissue.

• Korean Journal of Head & Neck Oncology
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• v.19 no.2
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• pp.127-132
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• 2003

Objectives: The best treatment for the malignant parotid tumor still remains to be defined, and a better knowledge about the tumor features that predict the treatment result is needed. The aim of this study is to evaluate the treatment outcomes and to suggest the optimal treatment modality for the parotid cancer. Materials and Methods: The clinicopathologic characteristics of 113 patients who were treated for parotid cancer from January 1990 to December 2002 were retrospectively analysed. Univalate analyses were performed to establish the prognostic influence of pateint age, gender, tumor size, histologic grade and lymph node metastasis. Results: The mean age was 46.4 years old (15-81 years) and. The male to female ratio was 1 : 1.1. The chief complaint was a palpable mass in 85%, pain was in 12.4% and facial nerve palsy was accompanied with 2.7%. The mean tumor size was 3.5cm in diameter. The most common malignant tumor was mucoepidermoid carcinoma (33.6%), followed by acinic cell carcinoma (15%), adenoid cystic carcinoma (11%), carcinoma expleomorhpic adenoma (11%), basal cell carcinoma (7%). The most common operative procedure was total parotidectomy (47.8%) and various types of cervical lymph node dissection were added in 69.9%. Postoperative radiotherapy was done in 61.1 %. Postoperative complications developed in 54 cases (47.8%), including 46 cases (40.7%) of facial nerve palsy and 9 cases (8%) of Frey's syndrome. Recurrences developed in 21 cases (18.6%) and deaths in 15 (13.3%). Cumulative survival at 5 year was 75.4%. Univariate analysis of clinical factors showed that histologic grade and positive cervical lymph node significantly influenced survival (p<0.05). Conclusion: These results suggests that the radical resection with lymph node dissection and postopertaive XRT would be necessary to improve the survival of the patients with high grade cancer or positive lymphnode metastasis.

• Journal of the Korean Institute of Landscape Architecture
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• v.44 no.6
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• pp.51-59
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• 2016

The purpose of this study is to improve interaction with the construction subject by analyzing the contents and contents of users' involvement in landscaping works. For this purpose, this study selected the Gwanggyo Residential Land Development District Public Landscape Project in Suwon, Gyeonggi Province. For four years before and after the completion, the opinions of tenants were used as research data. Both qualitative and quantitative analyses of 412 complaints received by the project implementation office and local government were conducted. As a result, first, the main purpose of suggesting opinions was 'demanding and expressing complaints', and there were many 'parks' and 'rivers'. In terms of content, "quality" was the most pointed out, but many kinds of trees, such as tree planting, ecological river construction, and pavement construction were also mentioned. Second, the extraction of key words from content analysis was the most common method. Followed by 'additional foodstuff' and 'moving to the toilet and management building'. Much of the point of view about dead wood has continued to be conspicuous in the process of waiting to be dealt with at the time of transplanting. Third, the validity of the contents of the complaints was evaluated as a five - point scale. Therefore, the opinions raised were unreasonable, but overall, there were more complaints with certain objectivity.

• Journal of Digital Convergence
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• v.18 no.3
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• pp.23-34
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• 2020

This study aims to verify the mediating effect of mobile social participation on the relationship between the mobile device capability and life satisfaction. Using the data of 2018 Digital Divide Survey conducted by the National Information Society Agency(NIA), the mediating effect was verified by Baron & Kenny (1986)'s 3 step process, targeting 1,665 middle and older aged adults. The result is as follows: first, the mobile device capability of the middle and older aged people has a positive effect on life satisfaction. Second, the effect of the mobile device capability of middle and older aged people on life satisfaction is partially mediated by mobile social participation including expressing opinions on social concerns, proposing policies and filing a civil complaint, donation and volunteering work and online voting and responding to a poll. The result represents that the mobile device, such as a smart phone or a smart pad, capability of the middle and older aged group not only directly benefits the group but also helps expand their mobile social participation, which leads to, although indirectly, higher life satisfaction. Therefore, the study is expected to be a groundwork for a practical intervention for enlarging the use of mobile device and lifting digital information level of the elderly to encourage mobile social participation and drive life satisfaction.

• Journal of the korean academy of Pediatric Dentistry
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• v.27 no.4
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• pp.564-572
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• 2000

We decided among extraction, orthodontic traction and autotransplantation such as direction and position of unerupted tooth, degree of developing root apex, eruption space, being of supernumerary tooth or odontoma or cyst when tooth impacted. Autotransplantation is considered when orthodontic traction is unrealistic or when tooth movement can absorb root of neighbor tooth. The prognosis for successful autotransplantation is dependent on a number of factors such as root development, surgical technique, patient's age, endodontic treatment, time and type of splinting, preservation of periodontal ligament and storage medium. Especially when severe osseous defect is being, bone graft considered for reducing of mobility and for assisting recovery. In all cases, chief complaint is unerupted tooth and various causing factors were supernumerary, odontoma, ectopia and so on. Before autotransplantation, space regaining was done if needed and demineralized freezed dried bone and autogenous bone graft was done when there is severe osseous defect by extraction of supernumerary tooth or odontoma. Splinting was removed after 2-3weeks At 3-4weeks after autotransplantation, endodontic treatment was decided. At follow up check, normal recovery was done and there was no inflammatory or replacement root resorption in periapical radiograph.

• Journal of the korean academy of Pediatric Dentistry
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• v.29 no.3
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• pp.413-417
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• 2002

Mucocele is a mucous retention phenomenon which is caused by a laceration to the duct of minor salivary glands causing extravasation of mucin into the connective tissue forming a cyst-like space. Sialolithiasis of minor salivary glands and chronic obstruction of salivary glands may also cause such a phenomenon. Mucocele is a smooth, rounded sessile mass with diameters varying from 1 to 15mm of sudden appearance. Mucocele tying directly beneath the mucosa may rupture spontaneously and decrease in size, but frequently recurs. Lower lip is most frequently affected, and the mouth floor and buccal vestibule may also be affected. Enucleation of the cyst is needed and removal of minor salivary glands, marsupialization and cryotherapy may also be done. The mucocele frequently recurs after its removal. A 1-year-old female patient visited the hospital with a complaint of a swelling on the lower lip since 4 months before. She had no pain history but 4 months ago, fell and such symptom appeared since then. On her first visit, a bullous solid, opaque lesion of 5mm in diameter was noted. Treatment choice of surgical approach and nonsurgical approach were explained to the guardian. Considering the patient's age, the guardian agreed to a nonsurgical procedure. Treatment was carried out by tieing 3-0 silk to the base of the lesion. One week later, the tie loosened and was re-tied. A week later, the mucocele disappeared. Mucocele on the lower lip may be usually be treated by surgical removal, but this may traumatize the surrounding minor salivary gland causing it to recur. Also, surgicial removal may induce an ischemic change causing sialometaplasia. In case of young patients or children with management problems, non-surgical methods such as this tie method may be used. This tie method does not need any local anesthesia and has no pain, no secondary infection, and low bleeding tendency.