• Korean Journal of Head & Neck Oncology
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• v.15 no.2
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• pp.189-193
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• 1999

Objectives: Fine needle aspiration cytology(FNAC) is a well established preoperative diagnostic procedure in the thyroid nodules. However, diagnostic accuracy of FNAC varies according to the size and the structural characteristics of thyroid nodule. We performed the ultrasound guided FNAC(US-guided FNAC) for impalpable thyroid nodule, and estimated the sampling accuracy rate through a comparison study between the cytologic diagnosis and the final histologic diagnosis of the postoperative specimens in order to determine clinical efficacy of the US-guided FNAC. Materials and Methods: We evaluated 117 patients underwent US-guided FNAC from January 1997 to December 1998. These patients had 129 thyroid nodules to need cytologic examination. Whereas the nodules were so no graphically classified into cystic, solid, and mixed type according to echo pattern, the aspirated thyroid specimens were classified into benign, malignant, suspicious, and insufficient. Results: Positive sampling for diagnositc examination was achieved in 75 nodules(58.1%), and US-guided FNAC in our study showed the accuracy rate of 95.2%, false positivity rate of 0%, and false negativity rate of 5.5%. Conclusions: US-guided FNAC is a powerful techniques for evaluating cytologic characterics and allowing a reliable diagnositc result in the impalpable thyroid nodule. However, the experienced technique is recommanded in order to obtain the sufficient samples for reliable results.

• Archives of Craniofacial Surgery
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• v.18 no.3
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• pp.218-221
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• 2017

A solitary fibrous tumor is a relatively uncommon neoplasm that usually occurs in the pleura but occurs extremely rarely in the oral cavity. Reported herein is a rare case of a solitary fibrous tumor in the buccal cheek mucosa. A 50-year-old man visited the authors' hospital due to a buccal cheek mass whose size had increased. Excisional biopsy was done under local anesthesia. After the excisional biopsy, the patient was diagnosed to have a solitary fibrous tumor. In immunohistochemistry, the patient's solitary fibrous tumor was characterized by the expression of CD34 and CD99 on the neoplastic cells, and negativity for Bcl-2 and S-100. No recurrence or complication occurred for a period of 5 years. The growth of a primary solitary fibrous tumor in the buccal cheek mucosa is extremely rare and has been rarely reported in the South Korean medical literature. A solitary fibrous tumor must be distinguished from other spindle cell tumors. Presented herein is a case of primary solitary fibrous tumor in the buccal cheek mucosa. The relevant literature is briefly reviewed.

• Korean Institute of Interior Design Journal
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• v.23 no.1
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• pp.23-33
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• 2014

This is a study on the application of a dialectic way of thinking in terms of design methods, and has contents about the formation of new visual and the ways of process that are triggered by cognitive introspection. A ccordingly, the study has its purposes in interpretation and recommendation of new methodological systems around dialectic principles and ways of thinking on the works of the Dutch Architecture Exhibition carried out in Korea in 2013, with the theme of "Reuse" among the aspects expanding since the reflexive modernization. Firstly, the basic features of Dutch designs were connected to dialectic ways of thinking. After studying the basic concepts of dialectics from Greek philosophies to Kant, Hegel, Marx and Benjamin, the aspects of applying them onto creative works such as art, architecture and design were methodologically systematized. Through this process, it was confirmed that the existing concepts are newly rearranged rationally, logically and scientifically based on dialectic ways of thinking rather than subjectively or emotionally. From the study of the 12 art works, it was confirmed that the value of use and potential obstacles have been used as a design solution. Also, the process which is juxtaposed with the result by itself has been expressed and causes the alienation effect. Therefore, such dialectic ways of thinking was organized into a procedural flow of contradictory recognition on situations, drive due to negativity, mutual penetration, mutual transformation, abstraction, verbalizing and creation of new concepts, and it was confirmed that such finding was valid in securing creative possibilities as 'New Uses' rather than 'Re-uses'.

• Biomedical Science Letters
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• v.15 no.1
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• pp.47-53
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• 2009

Urinary bladder cancer is diagnosed through urine cytology and cytoscopy with biopsy. An atypical urothelial cast is often found by voided urine cytology in a papillary urothelial cell carcinoma. The objective of this study is to demonstrate the significance of the evaluation of urinary nuclear matrix protein (NMP22) level and Sure Path Liquid-based cytology (SP-LBC) as compared to the examination of atypical urothelial cast in voided urine sediment for monitoring bladder cancer. From October 2007 to January 2008, we observed 3240 patients who visited the emergency laboratory of urology of Soonchunhyang University, Cheonan Hospital. Both NMP22 measurement and SP-LBC were performed in 31 patients who were positive in an atypical urothelial cast test. In particular, 26 men and 5 women were found to be atypical urothelial cast-positive persons. The average age for both men and women is 61.8. NMP22 test is positive in 23 of 31 cases (74.2%) from patients with atypical urothelial cast, while the test is negative in 8 of 31 cases (25.8%). The percentages of negativity, atypicality, suspicious malignancy, and malignancy in SP-LBC are 25.8% (8/31), 58.1% (18/31), 9.7% (3/31), and 6.5% (2/31), respectively. The relation of NMP22 positivity with the malignant degree in LBC is significant (P<0.01). Two malignant patients resulting from SP-LBC show the same results in histological examination. Overall, the study suggests the usefulness of NMP22 measurement and LBC as well as the examination of atypical urothelial cast for the diagnosis of early bladder cancer.

• Journal of the Korea Society of Computer and Information
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• v.22 no.1
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• pp.123-134
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• 2017

The ability to use information technology has become increasingly important as technological advances continue to sweep through the computing world, and education for improving computational thinking has become globally instituted. In South Korea, informatics subjects have been modified in the 2015 curriculum and are now compulsory in primary and secondary education. However, despite substantial financial investment and numerous studies promoting informatics education, there continues to be a serious lack of pre-service teachers capable of teaching computational thinking. This study investigated pre-service teacher programming education using App Inventor, their perceptions of App Inventor, and how use of the program affected teacher problem-solving abilities and self-efficacy. In the pre-test, the control group and experimental group showed no statistically significant difference; however, the post-test revealed that the two groups showed statistically significant differences in problem-solving skills and self-efficacy. The participants initially showed interest in using App Inventor; however, after practice-teaching and project-based learning, the participants demonstrated a growing negativity toward the program when they made errors and the functional limits of App Inventor became apparent. Although most participants stated that they would not use App Inventor in their classes, the positive statistically significant differences in problem-solving skills and self-efficacy indicate that this study could be utilized as a basis for building a teaching-learning program using App Inventor and creating an educational plan for teaching computational thinking.

• Journal of the Korean Chemical Society
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• v.37 no.6
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• pp.555-561
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• 1993

Ultraviolet spectrophotometric investigation has been carried out on the system of iododestannylation iodine and tetramethyltin in methanol. The transient CT absorption spectrum can be observed and the subsequent disappearance of CT absorption spectrum was accompained by the cleavage of tetramethyltin with iodine. From there, the rate constants for the iododestannylation were determined at 10, 25 and 35$^{\circ}C$ up to 1600 bar and the reaction rates were increased with increasing temperature and pressure. From these rate constants, the values of the activation parameters (${\Delta}V^\neq,\;{\Delta}{\beta}^{\neq},\;{\Delta}H^{\neq},\;{\Delta}S^{\neq}\;and\;{\Delta}G^{\neq}$) were obtained. The activation volumes and activation compressibility coefficients were both negativity. The activation enthalpies were positive and activation entropies had large negative values. From these values discussed in terms of solvent structure variation of transition state and mechanism. From these results, it was found that the reaction is followed with $S_E2$ mechaenism and weakened $S_E2$ mechanism nature by increasing pressure.

• Applied Chemistry for Engineering
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• v.25 no.1
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• pp.20-26
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• 2014

The interaction of p-halogenated phenol derivatives with the micellar system of tetradecyltrimethylammonium bromide (TTAB) was studied by the UV/Vis spectrophotometric method. Effects of substituents, additives, and temperatures on the solubilization of phenol derivatives have been measured. The results show that all the values of ${\Delta}G^o$ and ${\Delta}H^o$ were negative and the values of ${\Delta}S^o$ were positive for all phenol derivatives within the measured temperature range. The calculated thermodynamic parameters depended on the size, the electro-negativity, and the hydrophobic property of halogen substituents. The addition of n-butanol results in the decrement in tthe Ks values and the addition of NaCl caused the increment in the Ks values for all the phenol derivatives. From these changes we can postulate that the solubilization sites of the phenol derivatives in the micelle depend severely on properties of the halogen-substituent.

• Journal of the Korean Institute of Intelligent Systems
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• v.16 no.5
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• pp.537-543
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• 2006

There have been many recent studies on the nonlinear rainfall-runoff modeling, where the use of neural networks is shown to be quite successful. Due to fundamental limitation of linear structures, employing linear models has often been considered inferior to the neural network approaches in this area. However, we believe that with an appropriate extension, the concept of linear impulse responses can be a viable tool since it enables us to understand underlying dynamics principles better. In this paper, we propose the use of multiple impulse responses for the problem of rainfall-runoff analysis. The proposed method is based on a simple and fixed strategy for switching among multiple linear impulse-response models, each of which satisfies the constraints of non-negativity and uni-modality. The computational analysis performed for a certain Korean hydrometeorologic data set showed that the proposed method can yield very meaningful results.

• The Journal of Korean Society for School & Community Health Education
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• v.22 no.4
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• pp.39-48
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• 2021

Objectives: The purpose is to prepare measures to effectively improve college life adaptation by identifying relevance between interpersonal relation disposition and college life adaptation, college life stress and college life adaptation for dental hygiene students. Methods: 375 dental hygiene students attending some local universities in Gyeonggi-do were sampled for convenience. The results of this study are as follows. Results: First, As a result of interpersonal relation disposition according to general characteristics, superiority-dominance tendencies were higher in first and third graders, in groups with grades above 4.0 and groups with lower subjective economic levels. And the stress of college life was high for second graders and students with lower grades than 2.0. Second, According to the correlation between factors, governance-dominance, independence-responsibility, sympathy-acceptance, sociable-friendliness, and ostentation-intoxication of interpersonal tendency factors had proportional relationship with college life adaptation, rebellion-distrust and college life stress had inverse relationship. Third, The results of multiple regression analyses to identify factors that affect college students' adaptation to college life were in the order of stress in college life, first grade, sociable-friendliness, second grade, rebellion-distrust. Conclusion: In order to improve college life adaptation, counseling and practical mediation programs should be developed and applied to effectively manage and control the negativity and positivity implied by interpersonal relationships and college life stress.

• Journal of Digital Convergence
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• v.19 no.11
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• pp.471-483
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• 2021

The purpose of this study is to find out audience' response of virtual influencer at the starting line of virtual influencer marketing. Therefore, posts, comments, number of likes, and video reviews were collected from Instagram of virtual influencers active in Korea. Python 3.7 and Textom were used for data collection and analysis. Sentimental analysis showed that the rate of positivity was higher than the rate of negativity and neutrality. The appearance of virtual influencer was found to be a major factor in both positive and negative. Consumers' interest in virtual influencer could be inferred from the neutral sensibility. This study is meaningful in that it presented data to help establish strategies for virtual influencer marketing by examining consumer reactions to virtual influencer and identifying factors of positive and negative emotions toward virtual influencer.