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Flexural Behavior of Segmental U-Girder and Composite U-Girder Using Ultra High Performance Concrete (초고강도 섬유보강 콘크리트를 사용한 분절형 U거더 및 합성 U거더의 휨거동)

  • Lee, Seung-Jae;Makhbal, Tsas-Orgilmaa;Kim, Sung-Tae;Han, Sang-Mook
    • Journal of the Korean Recycled Construction Resources Institute
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    • v.5 no.3
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    • pp.290-297
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    • 2017
  • The flexural behavior tests of UHPC segmental U-girder and composite U-girder which has 160MPa compressive strength and 15.4m length were carried out. The test variables are volume fraction of steel fibers and slab over the U-girder. Each U-girder has longitudinal re-bars in web and lower flange. PS tendons which has 2 of 15.2mm diameter in upper flange and PS tendons which has 7 of 15.2mm diameter in lower flange were arranged and prestressed at onetime in U-girder connection stage. Enough strong prestressing force which applied to U-girder due to ultra high performance concrete strength can withstand the self weight and dead load in U-girder stage. By comparison with the brittle behavior of U-girder, composite U-girder showed the stable and ductile behavior. After the construction of slab over U-girder, flexural load capacity of composite U-girder can bear the design load in final construction stage with only one time prestressing operation which already carried out in U-girder stage. This simple prestressing method due to the ultra high strength concrete have the advantage in construction step and cost. The shear key which has narrow space has the strong composite connection between ultra high strength concrete U-girder and high strength concrete slab didn't show any slip and opening right before failure load.

Spatio-temporal Variations of Marine Environments and Phytoplankton Community in the Gochang Coastal Waters (GCW) of Southern West Sea in Korea (서해 남부, 고창연안해역의 해양환경 및 식물플랑크톤 군집의 시·공간 변동특성)

  • Yoon, Yang Ho
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.11
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    • pp.477-493
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    • 2020
  • This study conducted a seasonal survey to analyze the spatio-temporal variations of marine environments and phytoplankton community in Gochang Coastal Waters (GCW) from August 2016 to April 2017. In the results, the water temperature ranged from 2.1℃ to 34.5℃, showing a large seasonal variation, but the salinity changed from 31.14 psu to 32.64 psu. Therefore, the seasonal variations of water types in GCW were mainly determined by water temperature. The phytoplankton community consisted of 53 genera and 86 species, showing a relatively simple distribution. The phytoplankton cell density ranged from 2.2 to 689.2 cells mL-1, with an average of 577.2 cells mL-1, which was low in autumn and high in winter. The seasonal succession of phytoplankton dominant species was mainly diatoms during the whole year, Leptocylindrus danicus, Chaetoceros curvisetus, Skeletonema costatum-ls in summer, Paralia sulcata, Eucampia zodiacus in autumn, S. costatum-ls, Thalassiosira nordenskioeldii in winter, and S. costatum-ls, Asterionella glacialis in spring. In other words, the phytoplankton community showed high diversity in GCW throughout the year. According to the PCA, GCW were easily heated and cooled by radiant energy at lower depth, and the seasonal distributions of phytoplankton were determined by the supply of nutrients by re-fuelling of surface sediments due to the seawater mixing such as tidal mixing.

The Failure of Venture Firm: A Longitudinal Study of Failed Firms' Taxonomy, Failing Process, and Differences (벤처기업 실패의 동태적 과정: 실패의 유형, 과정 그리고 그 차이점에 대한 종단적 분석)

  • Chang, Soo-Duck
    • Journal of Korea Technology Innovation Society
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    • v.13 no.1
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    • pp.140-159
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    • 2010
  • The main purpose of this study is to improve the understanding of the failures of venture companies. The study attempts to analyze the causes and the processes of venture failures and the different paths that led to such failures. For the research, 116 firms registered with the Korea Venture Business Association in 1997 were surveyed and traced in 2000. A questionnaire was sent to 105 companies that were operating at the time and 76 of them returned responses. In 2008, the 76 companies were re-traced, and it was found that 41 of them had failed while 35 survived. Through this process, a set of longitudinal data was gathered about the changes in strategies, environments, and organizational structures. Accordingly, t-test and ANOVA analysis were performed on the different causes and processes of venture failures, as well as the taxonomy according to the changes in circumstances. Empirical findings can be summarized as follows. Venture companies failed due to various reasons and there were very different failing processes. In addition, this study found that various failing paths existed among failed venture companies and different factors affected company failures. Considering these findings, this research is clearly advanced and can be distinguished from other existing researches in terms of the dynamic understanding of the failures of venture companies.

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Fishing Experiment for Development of Unused Fishery Resources on the Deep Sea Bed of Korean East Sea (동해구 심해 미이용 자원의 어획 시험 연구)

  • Lee, Byoung-Gee;Lee, Ju-Hee;Shin, Hyeong-Il
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.22 no.4
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    • pp.61-70
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    • 1986
  • In accordance with a rapid growth of demani on aquatic animals, researches of the unused fishery resources On the deep sea b~d in the Korean Waters has been and will be required. The authors carried out a series of fishing experiments to investigate the available resources and to find the effective fishing method on the deep sea bed of the Korean East Sea. In the experiments, 19 kinds of traps which are different from each other in shape, mesh size and entrance diameter were used. The fishing experiments w~r;; carried out in four areas of 20Dm, 600.'11, 800m and 1000.'11 deep respectively, by the Pusan 402 (30:) GT) and the Pusan 403 (279GT), the training ships of National Fisheries University of Pusan, during August, 1986. The catc~ were analyzed with the size, the depth and the construction of traps. The results obtained can be summarized as follows: 1. Main species of the catch w~re pink shrimp, Pandalus bolelis, a kind of welks, Buccimum striatissimum and a kind of larg~ crabs. Chiono8cetes japonicus and the another species were few. 2. The CPUE value (expressed by the number of catch per trap in this paper) of pink shrimp was the highest in the depth of 20J-n around, and the value in the depth of 600.'11 or more decreased gradually with an increase of the depth. But, the value of Buccimum straitissimum was much higher in the depth of 6:J:)!1I or more than that in the depth of 200m around. On the other hand, the value of Chion:Jecetes japonjcus was very low in general. 3. The iniividual body size of the catch differed with the depth. Pink shrimps caught in the depth of 200m around were smaller than those in the depth of 600.'11 or more. In contrast with this, Baccimum striatissim:t.m caught in the depth of 200m around were larger than those in the depth of 600.'11 or more. 4. Depending on the selection curve in Ishida's method for the mesh size of trap webbing, the carapace length of pink shrimp and the shell length of Buccimum striatissimum which are equivalent to 100% relative catching efficiency can be estimated about 3.5cm and 6.5cm or so respectively. 5. The number of catch of pink shrimp and Buccimum striatissimum by the 60.'1'1.'11 entrance diameter of trap were less than that by the 90mm, 120mm and 150mm, even thogh the diffierence am~r, g 9:Jmm, 120.'11.'11 and 150:1'.'11 are not so large.

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Technical Status of Microwave Remote Sensing of Tropical Cyclones (열대저기압 마이크로파 원격탐사의 기술 현황)

  • Choi, Geun-Chul;Yang, Chan-Su;Pack, Han-Il
    • Proceedings of KOSOMES biannual meeting
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    • 2006.11a
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    • pp.193-199
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    • 2006
  • This article reviews several microwave instruments employed in observation and analysis of tropical cyclones (TCs), typhoon, and hurricanes. Microwave signals are useful for observing tropical cyclones with severe storms since it isn't severely absorbed by the clouds and rain in the storm. The instruments discussed include scatterometers, microwave radiometers, synthetic aperture radars (SARs), and rain radar from space. The date such as winds, rainfall and cloud-distribution in the TCs obtained by microwave instruments provide important informations for forecasting the intensity and path of the typhoon. For example, there're wind-distribution provided by SSM/I which has a wide swath, detailed wind fields from ERS-1, 2 scatterometers and RADARSAT-1 SAR and TRMM's rain radar pro 떠 ding high resolution. Operational satellite instruments lunched recently have improved upon the problems of low resolution and narrow swath indicated at the beginning microwave remote sensing. Understanding and practical using sufficiently about the microwave instruments will serve for searching the features such as generation and development of the TCs.

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A Study on Patients' Satisfaction and Service Utilization in the DRG Based Payment System - Patients who Experienced Cesarean Section Before and After the Demonstration Program - (DRG 지불제도에서 환자의 의료서비스 만족도와 제공량에 관한 연구 - 시범사업 전.후 제왕절개 분만 경험 산모를 대상으로 -)

  • Kim, Ji Sook;Park, Hayoung
    • Quality Improvement in Health Care
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    • v.7 no.2
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    • pp.190-202
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    • 2000
  • Background : The objectives of this study were to examine patients' satisfaction with the DRG based payment method and its association with their awareness of the method, to examine patient reported changes in doctors' caring attitude, level of their out-of-pocket payments, providers' acceptance of patients' request for additional services after the program, and to examine changes in service utilization recorded in medical records. Method : One hundred-four patients who had cesarean sections before and after the demonstration program at two hospitals located in Seoul participated in the study. Patients were surveyed before discharges when their charges were finalized. Their medical records were reviewed as well to collect data for service utilization during hospital stays. The association between patients' satisfaction with the payment method and their awareness of the method was analyzed by ${\chi}^2$-test, and the significance of changes in providers' acceptance of patients' request for additional services and service utilization after the program were examined by ${\chi}^2$-test and t-test, respectively. Results : A large proportion of patients did not know of the DRG based payment method at the time of survey and a significantly larger proportion of patients who came to the hospitals with the knowledge satisfied with the method. About the same proportion of patients reported improvement and deterioration in doctors' caring attitude compare to the previous hospitalizations and a similar result was found concerning out-of-pocket payments. Providers' acceptance of patients' request for medication, PCA and painless delivery decreased significantly after the program whereas the acceptance for additional hospital days and laboratory and radiology tests did not. Length of stay, the numbers of days on antibiotics and antianemic medication, and the number of blood tests decreased significantly after the program, however, decreases in the rate of antianemic medication and the number of urine analyses were not statistically significant. Re-operation, in-hospital death, and complications were not observed before and after the program. Conclusion : The study findings indicated a need for better patient education and publicity about the newly introduced payment method to improve their satisfaction with the system. Other study findings concerning service utilization and quality of care indicators were consistent with the government funded evaluation studies.

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Research on Practical Shopping Value and Consumer Attitudes on PB Products According to Perceived Quality (실용적 쇼핑가치와 지각된 품질에 따른 PB제품에 대한 소비자태도에 관한 연구)

  • Kim, Eun-Hee
    • Journal of Distribution Science
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    • v.10 no.10
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    • pp.35-43
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    • 2012
  • Purpose - The current analysis has been done in order to verify the difference between consumer attitudes on the distributor's PB products in terms of practical shopping value and attitudes about the product according to its perceived quality. Research design, data, and methodology - The target respondents of this study were those who have bought PB products at large-scale discount stores within the past six months. We asked homemakers, office workers, and students who live in Seoul or Daejon to respond to a questionnaire by filling out self-evaluations, and collected the completed questionnaires. To test the hypothesis, a t-test was carried out by group for 25 percent of the high and low rankings, including a quarter of the total respondents, to verify attitudes toward products and brands, purchase satisfaction, and re-purchase intention according to the practical shopping value and recognized quality of PB products. A variance analysis was conducted to see if there were differences among groups in terms of practical shopping value and perceived quality. Scheffe's back testing was used to identify differences between groups. Results - The result of the investigation of consumer attitudes according to practical shopping value is as follows. First, it was verified that consumer attitudes about PB products increase as practical shopping value increases. Second, there was no significant. Third, it was verified that repurchase intentions for PB products get higher as the practical shopping value of the consumer increases. The following is the result of the investigation of consumer attitudes according to the perceived quality of PB products. First, it was verified that the product attitude improves as the perceived quality of PB products increases. Second, the research confirmed that the brand attitude improves as the perceived quality of PB products increases. Third, consumer satisfaction is higher when the perceived quality of PB products is high. Fourth, this study verified that repurchase intentions for PB products are higher as the perceived quality of the product increases. Finally, the results of identifying differences between groups for perceived quality and shopping value are as follows. It was identified that there were differences in shopping value according to the characteristics of the groups. However, perceived quality does not change according to the characteristics of groups. Conclusions - These results have practical implications for the marketing strategy of PB products in order to satisfy consumer demands and provide a differentiated service by the distributor. In addition, it is suggested that a communication strategy may be necessary to increase brand loyalty and ensure the continual growth and value creation of PB products as symbolic products for distributors.

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Clinicopathologic Assessment of Ocular Adnexal Lymphoproliferative Lesions at a Tertiary Eye Hospital in Iran

  • Asadi-Amoli, Fahimeh;Nozarian, Zohreh;Bonaki, Hirbod Nasiri;Mehrtash, Vahid;Entezari, Samaneh
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.8
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    • pp.3727-3731
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    • 2016
  • Background: The most common type of ocular lymphoma is non-Hodgkin lymphoma (NHL), categorized into two groups: indolent (slow growing) and aggressive (rapid growing). Differentiating benign reactive lymphoid hyperplasia (RLH) from malignant ocular adnexal lymphoma (OAL) is challenging. Histopathology, immunohistochemistry (IHC) and flow cytometry have been used as diagnostic tools in such cases. Materials and Methods: In this retrospective case series, from 2002 to 2013 at Farabi Eye Center, 110 patients with ocular lymphoproliferative disease were enrolled. Prevalence, anatomical locations, mean age at diagnosis and the final diagnosis of the disease with IHC were assessed. Comparison between previous pathologic diagnoses and results of IHC was made. Immunoglobulin light chains and B-cell and T-cell markers and other immuno-phenotyping markers including CD20, CD3, CD5, CD23, CD10, CYCLIND1 and BCL2 were evaluated to determine the most accurate diagnosis. The lymphomas were categorized based on revised European-American lymphoma (REAL) classification. Results: Mean age ${\pm}$ SD (years) of the patients was $55.6{\pm}19.3$ and 61% were male. Patients with follicular lymphoma, large B-cell lymphoma or chronic lymphocytic leukemia/small cell lymphoma (CLL/SLL) tended to be older. Nine patients with previous diagnoses of low grade B-cell lymphoma were re-evaluated by IHC and the new diagnoses were as follows: extranodal marginal zone lymphoma(EMZL) (n=1), SLL(n=1), mantle cell lymphoma (MCL) (n=3), reactive lymphoid hyperplasia RLH (n=2). Two cases were excluded due to poor blocks. Flow cytometry reports in these seven patients revealed SLL with positive CD5 and CD23, MCLwith positive CD5 and CyclinD1 and negative CD23, EMZL with negative CD5,CD23 and CD10. One RLH patient was negative for Kappa/Lambda and positive for CD3 and CD20 and the other was positive for all of the light chains, CD3 and CD20. Orbit (49.1%), conjunctiva (16.1%) and lacrimal glands (16.1%) were the most common sites of involvement. Conclusions: Accurate pathological classification of lesions is crucial to determine proper therapeutic approaches. This can be achieved through precise histologic and IHC analyses by expert pathologists.

The Effects of the Q-Ray View on Reliability of Assessing a Tooth Status for Dental Hygiene Process (Q-Ray View 활용이 치위생과정을 위한 치아 검사의 신뢰도 향상에 미치는 영향)

  • Oh, Hye-Young;Jung, Hoi-In;Ku, Hye-Min;Kim, Baek-Il
    • Journal of dental hygiene science
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    • v.14 no.4
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    • pp.461-467
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    • 2014
  • The objective of this study was to evaluate the impact of the Q-ray view, a novel optical device on reliability of assessing a tooth status by dental hygiene students in the training for dental hygiene process. Twenty patients were enrolled in this study. Oral examinations were conducted by both seventeen third-year dental hygiene students and a trained faculty member. Traditional visual inspection was performed in phase I and then re-examined with Q-ray view in phase II. Restoration codes and lesion codes for each tooth were recorded separately according to the predefined criteria. As a measure of reliability, percent agreement and Cohen's kappa were determined. Agreements for each intraoral regions and types of lesion and restoration were calculated. Paired t-test and Pearson chi-square test for two proportions were used to compare mean Cohen's kappa and percent agreement at each phase. For the lesion code, mean kappa values of phase II for intraoral regions were significantly greater than that of phase I (p=0.017). For the both of the lesion code and restoration code, percent agreements of phase II for each types of lesion and restoration were significantly greater than that of phase II (p<0.001 and p<0.001, respectively). Especially difference of percent agreements between phase I and II for incipient caries, caries and fracture were significant for the lesion code (p=0.046, p<0.001, and p=0.029, respectively) and for not restored or sealed, tooth-colored restoration were significant for the restoration code (p<0.001 and p=0.011, respectively). The reliability of assessing a tooth status was improved when the Q-ray view used in dental hygiene student with beginner level of expertise. Q-ray view can be a promising device for conducting and educating the dental hygiene process better.

Consecutive automated production of carbon-11 labeled radiopharmaceuticals by sharing 11C-methylation reagent from one 11C-synthetic module

  • Park, Hyun Sik;Lee, Hong Jin;An, Hyun Ho;Moon, Byung Seok;Lee, Byung Chul;Kim, Sang Eun
    • Journal of Radiopharmaceuticals and Molecular Probes
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    • v.2 no.2
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    • pp.123-131
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    • 2016
  • Increasing clinical demand for carbon-11 labeled radiopharmaceuticals has triggered technological advances in fields of radiochemistry and automated modules. Even though carbon-11 has a short half-life ($t_{1/2}=20.4min$), the consecutive second production of carbon-11 labeled radiopharmaceutical in one $^{11}C$-synthetic module should be delayed at least over 4 h to avoid the high radiation exposure. We herein aimed to produce two different carbon-11 labeled radiopharmaceuticals ([$^{11}C$]PIB and [$^{11}C$]methionine) by sharing of [$^{11}C$]methylation source in one $^{11}C$-synthetic module. The synthesis of $^{11}C$-labeling reagents ($[^{11}C]CH_3I$ or $[^{11}C]CH_3OTf$) is fully automated using the commercial TRACERlab $FX_{C-pro}$ module and is readily adaptable to $^{11}C$-labeling reactor for [$^{11}C$]PIB as well as another $^{11}C$-labeling apparatus for [$^{11}C$]methionine via the three-way valve. After completing the [$^{11}C$]PIB production, the re-synthesized $[^{11}C]CH_3I$ was passed through the three-way valve connected the polyetheretherketone (PEEK) line and loaded into the C18 Sep-Pak cartridge including the methionine precursor. The labeled product [^${11}C$]methionine was purified by a simple cartridge separation and reformulated into saline. The radiochemical yield of [$^{11}C$]PIB and [$^{11}C$]methionine were $5.3{\pm}0.6%$ and $18.7{\pm}0.8%$ (n.d.c.), respectively, with over 97% of radiochemical purity. The specific activity of [$^{11}C$]PIB was over $110GBq/{\mu}mol$. Total production time of two radiopharmaceuticals needs about 2 h from $1^{st}$ beam irradiation including quality control tests. Final [$^{11}C$]PIB and [$^{11}C$]methionine were satisfied all quality control test standards.