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Effectiveness and characteristics of technology transfer consortia in public R&D sector: The case of Korean TT consortia (공공연구부문에서의 기술이전컨소시엄의 효과와 특성 연구: 공공기술이전컨소시엄 사례를 중심으로)

  • Park, Jong-Bok;Ryu, Tae-Kyu
    • Journal of Korea Technology Innovation Society
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    • v.10 no.2
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    • pp.284-309
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    • 2007
  • Technology transfer (TT) consortium is an affiliation of two or more public research institutions (PRIs) that participate in a common technology transfer activity or pool their resources together, with the objective of facilitating technology transfer. Based on empirical analysis of five regional TT consortia (2002-2006) operating in Korea, this paper suggests their effectiveness by employing a TT performance index (TTPI) and identifies possible characteristics involved, such as motivations, facilitators, barriers, and challenges. TTPI devised in the paper is a new composite TT performance index to measure how much the TT performance of a PH changed in a designated year compared to a base year. All the performance indicators of TTPI are well-structured based on the unique TT process that is prevalent in Korea. Further, TTPI can bring different size and focus of PRIs to the same scale for comparison by double-normalizing. The paper tests the effectiveness of TT consortium for the escalation of TT performances in member PRIs by highlighting the differences of TTPI's between 2005 and 2001. As a result, the paper found that the escalation of TTPI for member PRIs was greater than that for non-member PRIs. As for the characteristics of TT consortia, their respective factors obtained by TT expert survey were computed with proportion tests of differences (Z tests) to compare two perspectives between intramural and extramural groups. One of key findings is that there is general homogeneity in stakeholder perspectives regarding motivations, facilitators, barriers, and challenges. Some notable responses are as follow; the most probable motivation to join TT consortium is to share or exchange TT competences for enhanced performance. Second, the most probable facilitator is professional capability of consortium-hired personnel. Third, the foremost probable barriers to effective TT consortium are frequent change of consortium director and passive participation of member PRIs. Lastly, both publicizing TT consortia and developing performance metrics are the most important for the improvement of TT consortia. The understanding of the characteristics of TT consortia increases the likelihood of accelerated success, because TT consortia path from formation to termination encompasses many concepts, processes, principles, and factors. Finally, an analysis of the survey data combined with expert interview and observation data led the authors to derive five conditions as being critical to viable TT consortia in Korea at early stage of technology transfer systems. These conditions include policy infrastructure, proactive participation, excellent professionals, personal motivation, and teaming mechanisms. It is expected that the Korean evidence is a starting point to develop and refine the theory of TT consortia and for additional studies in other countries.

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Studies on the Morphology and Biology of a Parasitic Mite, Pyemotes tritici L.-F. & M. on the Cigarette Beetle(Lasioderma serricorne F.). (Pyemotes tritici L.-F. & M. 궐련벌레살이주머니응애의 형태(形態)와 생활사(生活史)에 관(關)한 연구(硏究))

  • Oh, M.H.;Kim, S.S.;Boo, K.S.
    • Korean journal of applied entomology
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    • v.24 no.1 s.62
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    • pp.15-18
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    • 1985
  • Studies were made on the morphology and life cycle of the mite, Pyemotes tritici $Lagr{\acute{e}}z$-Fossot & $Montagn{\acute{e}}$ (Trombidiformes; Pyemotidea) ,parasitic on larvae of cigarette beetle, Lasioderma serricorne F., which is one of the most serious pests of stored tobacco, cigar, and cigarette in Korea. One generation time was $20.9{\pm}0.7$ days out of which $9.5{\pm}0.3$ days were spent for feeding and $10.3{\pm}0.8$ days for reproduction of progenies. A female of this insect-parasitic mite produced $56.7{\pm}6.9$ progenies during her reproduction period. The body size of a newly-laid male or female was $280{\mu}m$ long and $85{\mu}m$ wide. As female of this mite sucked on, their abdomen grew larger and larger to reach $825{\mu}m$ in width and $0.346mm^3$ in volume after $9{\sim}10$ days. By sucking the humor of a host, the abdomen of a female mite became almost a global shape in two days. The increase rate of abdominal width was the biggest on the second or the third day of feeding while the volume of abdomen reached to the largest on $6{\sim}8$ days after feeding. The largest number of the daily young produced on 4-th day after a female began to reproduce.

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COMPARATIVE STUDY ON THE SHEAR BOND STRENGTH OF ALL-IN-ONE DENTIN BONDING SYSTEM APPLIED TO PRIMARY TEETH (유치에 적용된 All-in-One 상아질 접착 시스템의 전단강도에 관한 비교연구)

  • Kim, Dong-Cheol;Kim, Jong-Soo;Yoo, Seung-Hoon
    • Journal of the korean academy of Pediatric Dentistry
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    • v.34 no.4
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    • pp.560-568
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    • 2007
  • This study was performed to compare the shear bond strength of primary enamel & dentin treated by AQ Bond $Plus^{TM}$ and G $Bond^{TM}$, recently developed 6th generation dentin bonding system, to that of Single $Bond^{TM}$ being widely used. Also by observing the resin tag under scanning electron microscope, Resin tags of each material were also observed under scanning electron microscope and compared to one another. The possibility of clinical application of All-in-One system which has an advantage to reduce chair-time for children with difficult behavior pattern was evaluated. The results obtained are as follows: 1. No statistically significant difference between groups was found in shear bond strength of primary enamel. 2. In primary dentin, the shear bond strength of AQ Bond $Plus^{TM}$ was $1.15\;{\pm}\;0.37\;MPa$, G $Bond^{TM}$ was $1.69\;{\pm}\;0.74\;MPa$ and Single $Bond^{TM}$ was $0.56\;{\pm}\;0.11\;MPa$. There were no statistical difference between AQ Bond $Plus^{TM}$ and G $Bond^{TM}$ and between G $Bond^{TM}$ and Single $Bond^{TM}$, whereas statistically significant difference was found between AQ Bond $Plus^{TM}$ and Single $Bond^{TM}$. 3. Under scanning electron microscope, resin tags observed in AQ Bond $Plus^{TM}$ and G $Bond^{TM}$ were very weak and tangled while strong and thick tags were shown with many lateral branches in Single $Bond^{TM}$. The result of the present study coupled with the advantages of less working time over the previous generation suggests that All-in-One system might be effectively used in adhesive dental procedures for primary teeth.

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A STUDY OF SHEAR BOND STRENGTH OF ER:YAG LASER-IRRADIATED PRIMARY DENTIN (Er:YAG 레이저를 조사한 유치 상아질의 전단결합강도에 관한 연구)

  • Lee, Jin-Hwa;Kim, Jong-Soo;Yoo, Seung-Hoon
    • Journal of the korean academy of Pediatric Dentistry
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    • v.34 no.4
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    • pp.569-578
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    • 2007
  • This study was performed to compare the shear bond strength of self etching system and two bottle bonding system with or without laser preparation. Group I was prepared with high speed rotary instrument and $Prompt^{TM}$ L-$Pop^{TM}$, group II with Er:YAG laser and $Prompt^{TM}$ L-$Pop^{TM}$, group III with Er:YAG laser, 37% phosphoric acid and Single bond, group IV with Er:YAG laser and Single bond and group V with high speed, etching and Single bond. And also observation of the prepared and etched dentin surface were performed under scanning electro-microscope. The possibility of clinical application of laser preparation which might have an advantage to reduce pain for children with less unfavorable noise were evaluated. The results obtained are as follows; 1. Group V showed significantly higher bond strength than other groups. And group IV showed significantly lower bond strength than other groups. 2. There was no significant difference between group I and group III. 3. Group II showed significantly lower bond strength than group I, III, V, but showed significantly higher bond strength than group IV. 4. Under scanning electro-microscope, laser-preparated dentin surface showed high irregularity and no smear layer. The surface showed less irregularities and more exposed dentinal tubules with etching. Laser preparation has many advantages over conventional tooth preparation. But this method showed lower resin bonding strength. Laser preparated tooth surface differed from the conventionally preparated tooth surface. More researches are needed on suitable methods for laser preparated dentin surface.

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Effects of Some Environmental Factors on Japanese Yew (Taxus cuspidata Sieb. et Zucc.) (몇 발근환경인자(發根環境因子)가 주목삽수(揷穗) 발근(發根)에 미치는 효과(効果))

  • Kim, Chang Ho;Nam, Jung Chil
    • Journal of Korean Society of Forest Science
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    • v.70 no.1
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    • pp.1-6
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    • 1985
  • The purpose of this experiment lies in finding the most appropriate cutting condition of Taxus cuspidata Sieb. et Zucc. which has been considered valuable tree species in gardening. Statistical analysis was focused on the comparison of the average ratios of rooting between greenhouses and fields, based on the observation rooted autogenis. To conduct this survey, hardwood cutting of Taxus cuspidata Sieb. et Zucc. were performed at both places of experiment above on April 20, 1982 with rooting results calculated on October 31, 1982. After formation of cuttings, it was soaked in IBA 200 ppm for 12 hours and than put in a bed. A summary of the result is presented as follows; 1) Cutting at the greenhouse showed higher average rate of rooting than at fields. Same tendency was found regardless of the differences in treatment. 2) It was clear that IBA-treatment contributed remarkably to causing higher average rooting rate. As an evidence, when twenty centimeter cuttings were inserted sandy media, IBA-treated area resulted in eighty six percent of average rooting rate, as compared with only twenty three percent in nontreatment case. In case of field cutting, IBA-treatment brought about fifty three percent of rooting in comparison with eleven percent nontreatment. 3) When sandy soil, loam and brown soil were separately used as cutting media, the highest rooting rate was found in case of sandy soil, without any difference between the two experimental places above. 4) As a result of the analysis to seek the impact of the length of cuttings on rooting, the range of length form fifteen to twenty centimeter was apparently most appropriate. It was also found that the rate of rooting declined beyond twenty five centimeter. 5) Two kinds of rooting pattern were observed. One was the case that callus cell lump was created on the lower cut side of cuttings. Importantly, root radical were formed inside the lump to influence the germination of root system. The other relates to the case that adventitious root which look like lateral roots appeared at the stem region. In abstract, first, sandy soil was effectively recommended in case of hardwood cutting in April. Second, the most appropriate length of cuttings ranged between fifteen and twenty centimeters. Third, high density IBA treatment was clearly effective. Forth, for proper environmental management, both pre-disinfection of sail by sterilizer and maintenance of high relative humidity were essentially required.

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COMPARISON FOR THE RETENTION OF CASTING CROWN AND CEMENT THICKNESS FOLLOWING VARIOUS CEMENTS (수종의 세멘트에 따른 주조금관의 유지력 및 세멘트 두께의 비교)

  • Lee, Cheong-Hee;Jo, Kwang-Hun
    • The Journal of Korean Academy of Prosthodontics
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    • v.32 no.1
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    • pp.37-46
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    • 1994
  • The purpose of this study was to evaluate the effect of various cements on the retention of casting crown and the cement film thickness. To evaluate the retention of crown, thirty maxillary premolars were used and prepared to largely same dimension. According to the routine method, Non-precious metal crowns were made. The teeth and the metal crowns were divided into three groups and cemented under 5kg static pressure. Group I was composed of 10 teeth and 10 metal crowns and was cemented with zinc phohsphste cement. Group II was composed of 10 teeth and 10 metal crowns and was cemented with Panavia-EX cement. Group III was composed of 10 teeth and 10 metal crowns and was cemented with All-Bond & composite resin cement. After 5 days, the cemented specimens were mounted and the failure loads were measured by an Instron Universal Testing Machine. To evaluate the cement film thickness. 5 metal teeth and 5metal crowns from a prepared maxillary premolar were made. Two marks were flawed on the margin part of each surface at 4-surfaces of each specimen(one mark : crown, the other : metal tooth) and were measured the width with SEM photograph(80 sheets) before and after cementation(Panavia-EX, All-Bond cement, & ZPC) was made. Differences of the widths of marks between before and after were measured, and differences from 4-surfaces of a specimen cemented with a cement were measured and calculated. The results were as follows ; 1. There was a statistically significant difference between the failure loads of group III and the others(p<0.05). 2. There was a statistically significant difference between the cement film thickness of group III and the others(p<0.05).

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REMINERALIZATION EFFECT OF INTERPROXIMAL CARIES ADJACENT TO GLASS IONOMER RESTORATIONS: IN VITRO STUDY USING QLF (QLF(Quantitative light-induced fluorescence)를 이용한 글라스 아이오노머 수복물의 인접면 우식 재광화 효과에 관한 연구)

  • Lee, Hyeok-Sang;Hyun, Hong-Keun;Jang, Ki-Taeg
    • Journal of the korean academy of Pediatric Dentistry
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    • v.38 no.3
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    • pp.244-249
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    • 2011
  • This in vitro study compared the remineralization of incipient interproximal caries in the presence of three glass ionomer cements(highly-filled glass ionomer cement, resin-modified glass ionomer cement, compomer) and a resin composite(control). Thirty-two extracted premolars were selected based upon the lack of any visible demineralization. The teeth were coated in a transparent acid resistant nail varnish leaving $3{\times}3$ mm square. The teeth were subjected to the demineralizing buffer for 3 days and quantitative light-induced fluorescence(QLF) images of the subjects were taken. Proximal restoration was simulated by placing tooth specimens and the various glass ionomer cements in closed containers with artificial saliva at $37^{\circ}C$ and pH 7.0 with constant circulation. Further QLF images were subsequently taken at 30, 60, and 90 days. The changes of mineral loss(${\Delta}Q$) were evaluated by QLF and the change of ${\Delta}Q$(${\Delta}{\Delta}Q$) were compared between groups in order to evaluate the effects of remineralization. All data were analyzed using ANOVA and the post-HOC Dunnett C multiple comparison test at p<0.05. While ${\Delta}Q$(changes of mineral loss) increased for all treatments, the increases for three glass ionomer groups were significantly higher than that for the resin group at first month period. As time went on, the amount of ${\Delta}{\Delta}Q$ decreased.

Soil Physicochemical Properties of Tree Plantations in a Fire-disturbed Forest and an Undisturbed Stand in Ulsan Metropolitan City (울산광역시 산불피해지의 조림지와 미피해지의 토양 이화학적 특성)

  • Kim, Choonsig;Jo, Chang-Gyu;Baek, Gyeongwon;Park, Seong-Wan;Cho, Hyun-Seo;Ma, Ho-Seop
    • Journal of Korean Society of Forest Science
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    • v.105 no.2
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    • pp.167-176
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    • 2016
  • This study was carried out to compare soil physicochemical properties and nutrient concentrations of tree leaf between planted forests following forest fire and an undisturbed forest in the Bongdaesan mountain, where is located in the Ulsan metropolitan city. We established three deciduous tree planting (Liriodendron tulipifera L., Prunus yedoensis Matsum and Quercus acutissima Carruth.) plots, one unplanted plot following four-year forest fire and one undisturbed plot (Pinus densiflora S et. Z). Carbon (C) stocks in the organic horizon were significantly lower in the tree planted plots ($2394-3551kg{\cdot}C{\cdot}ha^{-1}$) or the unplanted plots ($3689kg{\cdot}C{\cdot}ha^{-1}$) than in the undisturbed plot ($9388kg{\cdot}C{\cdot}ha^{-1}$). However, phosphorus (P), potassium (K) and magnesium (Mg) stocks in the organic horizon were not significantly different among the treatments. Soil water phase and soil pH were significantly higher in the P. yedoensis plot (water phase: 13.7-18.4%; soil pH: 4.62- 4.80) than in the undisturbed plots (water phase: 7.0%; soil pH: 4.10). Soil organic C concentration was slightly higher in the tree planted plots (1.89-3.60%) than in the unplanted (1.41%) plots. Soil Ca and Mg stocks at 10 cm of soil depth were significantly higher in the P. yedoensis and L. tulipifera plots than in the unplanted or undisturbed plots. Nutrient concentrations (Ca and Mg) of leaf were significantly higher in the L. tulipifera than in the Q. acutissima and the undisturbed pine plots. The results indicate that P, Ca, and Mg stocks in the organic horizon was not affected by tree planting, but Ca and Mg stocks at 10 cm of the soil depth were enhanced by the tree species established following four-year forest fire.

The infestation states and changing patterns of human infecting metacercariae in freshwater fish in Kyongang-do and Kyonggi-do, Korea (식이성 윤충류질환의 관리전략수립을 위한 감염원의 역학 및 병원체의 생물학적 특성에 관한 조사연구 - 경상도내 3개 강 및 경기도내 4개 하천에서 채집한 민물어류의 인체기생 흡충류 피낭유충 감염상 및 변동)

  • 임한종;김기홍
    • Parasites, Hosts and Diseases
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    • v.34 no.2
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    • pp.95-106
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    • 1996
  • The infestation rates and abundances of human infecting metacercariae (Clonorchis sinensis, Metcgonimus spry. , Centrocestus crmatus, Echinostoma hortense, Echinochusnus japonicw, Clinostomum complanctum) in freshwater fish were investigated at the three river areas - Taewhagang (river), Hyongsangang (river), Nakdonggang (river) - in Kyongsang-do and at four streams - Yonpungchon, Munsanchon, Kyonganchon, and Konjiamchon- in Kyonggi-do, Korea in 1994-1995. The fish caught at Taewhagang were heavily infested with metacercariae of Clonorchis sinensis and Centrocestw armctus. At Hyongsangang, Zncco platypus and Z. temmincki were moderately infested with metacercariae of C. crmctus. Chomanpo, at the basin of Nakdonggang, was still endemic for C. sinensis. In the fish caught at four streams of Kyonggi-do, metacercariae of C. sinensis exhibited the highest infestation rate and intensity out of 6 species of metacercariae. The infestation intensity of C. sinensis metacercariae in fish flesh was markedly different according to each division of flesh. The cause of this difference was conjectured as a result of larval behavior. The metacercariae of C. omnt5 were found in almost all parts, except scales and fins, of fish. The infestation rates and intensities of C. sinensis and C. armntus metacercariae in Taewhagang greatly increased as compared with those of previous reports . RhinoBobius bmnneus and Aconthorhone5 macropterus are newly recorded intermediate hosts of Echinostonn hortense. The reason of large differences from previous data was discussed and the standard method of metacercaria examination was proposed.

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Usefulness of Flow Composite Image in Raynaud Scan ($^{201}Tl$) ($^{201}Tl$을 이용한 레이노 검사에서 동적 Composite 영상의 유용성)

  • Kim, Dae-Yeon;Shin, Gyoo-Seol;Oh, Eun-Jung;Kim, Gun-Jae
    • The Korean Journal of Nuclear Medicine Technology
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    • v.14 no.1
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    • pp.101-104
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    • 2010
  • Purpose: Raynaud scan is divided to flow, blood pool and local-delay image. Usually, we evaluate comparison through blood pool and local-delay image. We will evaluate about usability when comparative observe blood image and local-delay image in Raynaud scan that used $^{201}Tl$ as making flow image to one sheet of images. Materials and Methods: We have selected 29 Raynaud phenomenon patients aged 14~68 years who visited department of vascular surgery between Feb. 2008 and Aug. 2009. An intravenous injection $^{201}Tl$ of 111 MBq (3 mCi) to opposite side diagonal line limbs above an internal auditing department. Equipment used Philips gamma camera forte A-Z, and collimator used LEHR. Matrix size set up to each $64{\times}64$, $128{\times}128$, $256{\times}256$ and zoom factor used to full field. Protocol of dynamic is 2 second to 155 frames. Blood pool and delay count to 300 second. We set up ROI by a foundation to data acquired in PEGASYS processing program. Each results were analyzed with the SPSS 12.0 statistical software. Results: Each averages of count ratio (Rt / Lt) to have been given at composite image, a blood pool image, delay images analyzed at Raynaud phenomenon patients is $1.25{\pm}0.39$, $1.20{\pm}0.33$, $1.11{\pm}0.17$. The sample analysis results of blood pool image and delay image contented itself with p<0.029. Also, there don't have been each difference, and blood pool image, delay image regarding composite image was able to know. Conclusion: We were able to give help for comparison to evaluate a blood pool image and a local delay image at the Raynaud scan which used $^{201}Tl$ while making a flow image to one sheet image. Identification to be visual too was possible. If you are proceeded a researcher that there was further depth, you are more appropriate for, and you may get useful information.

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