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Empirical Analysis of Accelerator Investment Determinants Based on Business Model Innovation Framework (비즈니스 모델 혁신 프레임워크 기반의 액셀러레이터 투자결정요인 실증 분석)

  • Jung, Mun-Su;Kim, Eun-Hee
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.18 no.1
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    • pp.253-270
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    • 2023
  • Research on investment determinants of accelerators, which are attracting attention by greatly improving the survival rate of startups by providing professional incubation and investment to startups at the same time, is gradually expanding. However, previous studies do not have a theoretical basis in developing investment determinants in the early stages, and they use factors of angel investors or venture capital, which are similar investors, and are still in the stage of analyzing importance and priority through empirical research. Therefore, this study verified for the first time in Korea the discrimination and effectiveness of investment determinants using accelerator investment determinants developed based on the business model innovation framework in previous studies. To this end, we first set the criteria for success and failure of startup investment based on scale-up theory and conducted a survey of 22 investment experts from 14 accelerators in Korea, and secured valid data on a total of 97 startups, including 52 successful scale-up startups and 45 failed scale-up startups, were obtained and an independent sample t-test was conducted to verify the mean difference between these two groups by accelerator investment determinants. As a result of the analysis, it was confirmed that the investment determinants of accelerators based on business model innovation framework have considerable discrimination in finding successful startups and making investment decisions. In addition, as a result of analyzing manufacturing-related startups and service-related startups considering the characteristics of innovation by industry, manufacturing-related startups differed in business model, strategy, and dynamic capability factors, while service-related startups differed in dynamic capabilities. This study has great academic implications in that it verified the practical effectiveness of accelerator investment determinants derived based on business model innovation framework for the first time in Korea, and it has high practical value in that it can make effective investments by providing theoretical grounds and detailed information for investment decisions.

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Diffusion-Weighted MR Imaging of the Brain Tumors: The Clinical Usefulness (두개강내 종양의 확산강조자기공명영상: 임상적 유용성)

  • 이영철;서정진;정광우;강형근;김윤현
    • Investigative Magnetic Resonance Imaging
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    • v.4 no.1
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    • pp.34-41
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    • 2000
  • Purpose: To evaluate the clinical usefulness of diffusion weighted MR imaging(DWI) in the differential diagnosis of brain tumors. Materials and methods: DWI and conventional MR images of nineteen patients with brain tumors(10 metastatic tumors, 4 high grade gliomas, 4 low grade astrocytomas, one oligodendroglioma)were obtained on 1.5T unit. DWI was obtained using single shot spin echo planar imaging with b-value near 1000. We analyzed the signal intensities of lesions including solid portion, necrotic or cystic portion and peritumoral edema of brain tumors (classified five grades comparison with the signal intensities of brain parenchyma and CSF)and calculate the SIR(signal intensity ratio)of lesions to the contralateral normal brain parenchyma. We analyzed statistically the signal intensities and SIR of tumors using independence T test. Results: In solid portions of tumors, all the metastatic tumors and high grade gliomas showed high signal intensities, but low grade astrocytomas and oligodendroglioma showed iso or slight high signal intensities to the normal brain parenchyma. The SIR of solid portion has positive correlation with malignant pot ential(metastatic tumors 1.52, high grade gliomas 1.38, low grade astrocytomas 1.16, oligodendroglioma 1.31)(p < 0.05). In peritumoral edema where seen in 14 tumors, seven of 10 metastatic tumors and two of 4 high grade gliomas showed iso signal intensities, whereas edemas in other 5 brain tumors showed hyperintense to the normal brain parenchyma. The SIRs of peritumoral edemas in metastatic tumors (1.14) was lower than high grade gliomas(1.31),but statistically insignificant. The SIR of cystic or necrotic portion of brain tumors was 0.63. In non enhancing solid portions, three of six cases showed hyperintense to the adjacent peritumoral edema. Conclusion: On DWI, the signal intensities of solid portion has positive correlation with malignant potential, and perilesional edema of brain tumors appear various signal intensities owing to "T2 shine through effect" and the extensiveness of vasogenic edema. Another merit using DWI on the evaluation of brain tumors is to improved better delineation of tumor margins from the adjacent edemas, especially at the non enhancing solid portion of the tumors.

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Joint stability of internal conical connection abutments with or without hexagon indexes: an in vitro study (내부연결 원추형 임플란트의 육각구조의 유무에 따른 연결부 안정성: 실험적 연구)

  • Lee, Sang-Woon;Cha, Min-Sang;Lee, Ji-Hye;Cho, Lee-Ra;Park, Chan-Jin
    • Journal of Dental Rehabilitation and Applied Science
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    • v.36 no.2
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    • pp.95-103
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    • 2020
  • Purpose: The purpose of this study was to compare the axial displacement of the hexagonal and conical abutment in internal conical connection implant after screw tightening and cyclic loading. Materials and Methods: Internal conical connection implants were divided into two groups (n = 10): group HEX, hexagonal abutment; and group CON, conical 2-piece abutments. The axial displacement and removal torque values were measured after 30 Ncm torque tightening and 250N loading test of 100,000 cycles. The Student t test with 5% significance level was used to evaluate the data. Results: HEX group demonstrated significantly higher axial displacement values after 30 Ncm tightening in comparison to the CON group (P < 0.05). No significant difference was found in axial displacement after cyclic loading (P = 0.052). Removal torque loss before and after the cyclic loading both revealed no significant difference between groups (P = 0.057 and P = 0.138). Removal torque value decreased after cyclic loading in both groups (P < 0.05). Conclusion: Overall, both abutment with or without hexagon index presented similar biomechanical performance except HEX group demonstrated significantly more axial displacement after applying tightening torque.

A Correlation between Stress and Activities of Daily Living related to the Ego-defense Mechanism in Stroke patients (뇌졸중 환자의 자아방어기제에 따른 스트레스와 일상생활활동 수행능력과의 상관관계)

  • Ryu, Sung-Hyun;Choi, Hyeon;Jeon, Ji-Hye;Choi, Su-Ji
    • The Journal of Korean society of community based occupational therapy
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    • v.5 no.2
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    • pp.1-9
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    • 2015
  • Objective : This study is to investigate the correlation of Ego-degense mechanism, stress and activities of daily living of stroke patients. Methods : The study was carried out from March 14, 2014 to May 15, 2015. A survey was conducted at a university hospital and three rehabilitation hospitals located in Daegu and Busan. For statistical analysis, frequency analysis, independent sample t-test, and Pearson correlation coefficient were used in this study. Results : As a result of the mature Ego-defense mechanism grop was more stressful than immature Ego-defense mechanism group(p<.05), mechanism group also showed better performance in activities of daily living activity(p<.05). Conclusion : The higher stress in stroke patients related to the disability to perform activities of daily living. Psychosocial rehabilitation for factors such as stress as well as physical function in stroke patients in the rehabilitation of stroke patients by using the Ego-defense will have a significant impact on an individual's personality or lifestyle.

Survey About Current Status of Pediatric and Adolescent Physical Therapy: Focus on Pediatric and Adolescent Rehabilitation Hospitals in Seoul and Gyeonggi Province (소아 청소년 물리치료 실태 조사: 서울 경기 지역 소아 청소년 재활병원을 중심으로)

  • Kim, Jeong-soo;Min, Kyoung-chul
    • Therapeutic Science for Rehabilitation
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    • v.12 no.4
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    • pp.67-80
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    • 2023
  • Objective : This study aimed to investigate the current status of physical therapy in children and adolescents. Methods : Sixty questionnaires from physical therapists treating children and adolescents with disabilities were analyzed. The questionnaire consisted of questions on physical therapy, participants, satisfaction, and the assessment of pediatric and adolescent physical therapy. Descriptive statistics and frequencies were used to investigate the current status, participants, and satisfaction. Differences between physical therapy participation difficulty, importance-ability of major aspects of pediatric and adolescent physical therapy, and therapy goal frequency were analyzed using paired T-test. Results : 11 to 15 cases (66.7%) and one-on-one treatment (95.0%) were performed independently (95.0%). The main ages of the subjects were preschool and school, the diagnoses were brain lesions and developmental delay, and treatment was conducted for up to 20 years or older. Satisfaction with pediatric and adolescent physical therapy was high (70.0%), as was the intensity of work (71.7%). Neurodevelopmental therapy, gait training, and goal-directed rehabilitation were the main treatments, and Gross Motor Function Measures of 88 and 66, respectively, were used. Respondents said that current fee system is inadequate (66.1%) and appropriate fee system is needed. Conclusion : This study extensively investigated the content of and factors related to pediatric and adolescent physical therapy. Based on the current situation, efforts to improve the expertise and continuity of pediatric and adolescent physical therapists and apply the latest treatment techniques are required.

The Effect of Leisure Satisfaction of the Elderly in China on Their Self-Efficacy and Psychological Well-Being in Calligraphy Activities (서예활동에 대한 노인의 여가만족이 자기효능감 및 심리적 안녕감에 미치는 영향)

  • Qin Yu;Feng Meng;Lee Jaewoo
    • The Journal of the Convergence on Culture Technology
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    • v.10 no.2
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    • pp.365-371
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    • 2024
  • The purpose of this study was to investigate the effect of leisure satisfaction according to calligraphy activities of the elderly on self-efficacy and psychological well-being. In order to conduct this study, the researchers surveyed 306 elderly people aged 65-76 or older from late November to early December 2023 in Anyang City and Xinxiang City, Henan Province, China. In order to verify the research hypothesis, the researchers performed frequency analysis, descriptive statistics analysis, and Pearson correlation analysis using IBM SPSS Statistics 25, and then performed independent sample T-test and one-way analysis of variance (One-Way ANOVA). To verify the hypothesis through the measurement concept, related verification was conducted for Hayes PROCESS macro and Bootstrap. As a result of the study, first, there is a gender difference in leisure satisfaction, leisure satisfaction, self-efficacy, and psychological well-being, and leisure satisfaction and psychological well-being differ significantly according to age. Second, it was found that leisure satisfaction had a positive effect on self-efficacy. Third, it was found that leisure satisfaction had a positive effect on psychological well-being. Fourth, leisure satisfaction was found to have a positive effect on psychological well-being. Therefore, in order to increase the leisure satisfaction and psychological well-being of the elderly, it is necessary to carefully develop a calligraphy activity system to increase self-efficacy.

A Study on the Differences in Awareness of the Social Value of Public Libraries between Public library Users and Non-Users: Focused on Paju City (공공도서관의 사회적 가치에 대한 이용자와 비이용자의 인식 차이에 관한 연구 - 파주시를 중심으로 -)

  • Dong-Geun Oh;Dong-Jo Noh
    • Journal of the Korean BIBLIA Society for library and Information Science
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    • v.35 no.1
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    • pp.47-71
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    • 2024
  • This study aims to compare the awareness of the social value of public libraries between users and non-users to materialize the abstract concept of social value and, thereby, to present measures that can be applied to the library field. For this purpose, a survey was conducted in person or online for 15 days from May 7, 2023, targeting Paju citizens. Frequency analysis, factor analysis, independent samples t-test, and one-way analysis of variance were conducted on 206 valid response copies using SPSS 25.0. In the results, it is shown that, first, for awareness of the social value of public libraries according to socio-demographic characteristics, there were significant differences depending on age, with in particular, awareness among those in their 10s and 40s being higher than other age groups. For awareness of community development, the awareness of the female group was higher than that of the male group, while, for the awareness according to occupation, it is shown that awareness was highest in the following order: student, others, housewife, self-employed, and office worker. Second, for the awareness of the social value of public libraries, the awareness of the user group was higher than that of the non-user group in all areas. Third, for awareness of the social value of public libraries according to the level of library use, there was no significant difference between groups. In conclusion, it is suggested that measures to encourage non-users to become users, develop new content and services targeting male group and those in their 60s, and 20s, and strengthen community activities are needed to raise awareness of the social value of Paju City public libraries in the future.

Comparison of crown designs of different dental occupational groups, using CAD-CAM (CAD-CAM을 이용하여 디자인한 금관의 치과 직업군에 따른 형태 비교)

  • Kim, TaeHyeon;Kim, Jong-Eun;Lee, Ah-Reum;Park, Young-Bum
    • The Journal of Korean Academy of Prosthodontics
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    • v.54 no.3
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    • pp.234-238
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    • 2016
  • Purpose: Increasing use of computer aided design-computer aided manufacturing (CAD-CAM) system and number of design software made design of restoration easy and quick. Outcome of restoration has been dependent on dental technician's wax up proficiency, dentists can design restoration for themselves now. This study aims to investigate the outcome of restoration designs, according to handling skill of CAD-CAM design tool. Materials and methods: A patient's mandibular right 1st molar was prepared. After taking impression, stone model was made, scanned the stone model with 3 shape intra-oral scanner, stereolithography (STL) file was extracted. With 3shape dental designer, one dental technician with more than 5 years work experience (designer 0) and three dental technicians with less than 2years work experience (designer 1, 2, 3-group DT) and 4 1st year residents (designer 4, 5, 6, 7-group RT) designed gold crown on the same STL file. Designed crown's MD (mesio-distal) and BL (bucco-lingual) diameter, height of crown, inter-cuspal distance, number of occlusal contact points were compared. Statistical analysis was carried out, test of normality within each group, using independent t-test. Number of contact points were compared, using Wilcoxon signed-rank test. Results: There was no significant difference between group DT and group RT. Number of contact points also resulted in no significant difference. Conclusion: The outcome of each designed crowns showed no statistical differences, in values which can be expressed as numbers. Subjective factors were different. With increasing proficiency in handling designing software, fabrication of restorations according to each designer's occlusal concept can be made easy.

ENAMEL ADHESION OF LIGHT-AND CHEMICAL-CURED COMPOSITES COUPLED BY TWO STEP SELF-ETCH ADHESIVES (2단계 자가 산부식 접착제와 결합된 광중합과 화학중합 복합레진의 법랑질 접착)

  • Han, Sae-Hee;Kim, Eun-Soung;Cho, Young-Gon
    • Restorative Dentistry and Endodontics
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    • v.32 no.3
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    • pp.169-179
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    • 2007
  • This study was to compare the microshear bond strength $({\mu}SBS)$ of light- and chemically cured composites to enamel coupled with four 2-step self-etch adhesives and also to evaluate the incompatibility between 2-step self-etch adhesives and chemically cured composite resin. Crown segments of extracted human molars were cut mesiodistally, and a 1 mm thickness of specimen was made. They were assigned to four groups by adhesives used: SE group (Clearfil SE Bond) AdheSE group (AdheSE), Tyrian group (Tyrian SPE/One-Step Plus), and Contax group (Contax) Each adhesive was applied to a cut enamel surface as per the manufacturer's instruction. Light-cured (Filtek Z250) or chemically cured composite (Luxacore Smartmix Dual) was bonded to the enamel of each specimen using a Tygon tube. After storage in distilled water for 24 hours, the bonded specimens were subjected to ${\mu}SBS$ testing with a crosshead speed of 1 mm/minute. The mean ${\mu}SBS$ (n=20 for each group) was statistically compared using two-way ANOVA, Tukey HSD, and t test at 95% level. Also the interface of enamel and composite was evaluated under FE-SEM. The results of this study were as follows ; 1. The ${\mu}SBS$ of the SE Bond group to the enamel was significantly higher than that of the AdheSE group, the Tyrian group, and the Contax group in both the light-cured and the chemically cured composite resin (p < 0.05). 2. There was not a significant difference among the hdheSE group, the Tyrian group, and the Contax group in both the light-cured and the chemically cured composite resin. 3. The ${\mu}SBS$ of the light-cured composite resin was significantly higher than that of the chemically cured composite resin when same adhesive was applied to the enamel (p < 0.05). 4. The interface of enamel and all 2-step self-etch adhesives showed close adaptation, and so the incompatibility of the chemically cured composite resin did not show.

Modeling Study of Development of Dying Well Education Program for the Medical Personnel in Korea (의료진 대상 웰 다잉 교육프로그램 개발을 위한 모델링에 관한 연구)

  • Kim, Kwang-Hwan;Kim, Yong-Ha;Ahn, Sang-Yoon;Lee, Chong Hyung;Hwang, Hye-Jeong;Lee, Moo-Sik;Kim, Moon-Joon;Park, Arma;Shim, Moon-Sook;Song, Hyeon-Dong
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.15 no.10
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    • pp.6234-6241
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    • 2014
  • The purpose of this study was to examine the status of medical staff stress and accommodating manners on the death of patients in a hospital setting for serving the basic information to develop a death education program of medical personnel from April 1 to April 30, 2014. A survey was performed on 353 medical personnel at K university hospital, located in Daejeon metropolitan city. Frequency analysis, chi-square test, and independent t-test were used to analyze the data. The results showed that 'to understand the value of the time and preparedness of a meaningful future' were the most important perspectives on the contents of death education (p<0.05), 'in order to change perceptions and attitudes toward death positively' was the most important reason why they required death education'(p<0.05), 'case-based teaching and problem-based learning' was the most effective way of death education (p<0.05), 'negative or hostile response of a patient's guardian to medical personnel' was the largest stress that medical personnel confront upon witnessing a death'(p<0.05). An understanding of the death of patients by medical personnel and an awareness of the need for death education will help improve the understanding of the patient, their guardian, and medical personnel themselves. The main findings will contribute to the development of a specific death education program on the medical personnel in a hospital setting.