• Title/Summary/Keyword: Priming time

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Influence of Delay Time on the Ground Vibration (발파공간 지연시차가 지반진동에 미치는 영향)

  • Kim, Ji-Soo;Choi, Tae-Hong;Lee, Chang-Won
    • Explosives and Blasting
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    • v.32 no.2
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    • pp.1-8
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    • 2014
  • In this study, 16 test blastings had been carried out with different spacings, burdens, drilling lengths, and charges per delay for investigating the characteristics of ground vibration propagation, which depends on the delay time. From the tests, it was possible to derive a ground vibration equation. Using the equation, the characteristics of ground vibration could be investigated by analyzing the nomogram and predicting the Peak Particle Velocity (PPV), which are influenced by the delay time and the priming location. The trend of ground vibration change depending on the delay time was analyzed for the standards charges of 0.5, 1.6, 5, and 15 kg, which were suggested in "Blasting design and construction guidelines to road construction" by the Ministry of Land, Infrastructure and Transport. From the study, it would be possible to suggest a favorable vibration control method, which depends on the charge.

INFLUENCE OF APPICATION TIME OF SELF-ETCHING PRIMERS ON DENTINAL MICROTENSILE BOND STRENGTH (자가 산부식 프라이머의 적용시간이 상아질의 미세인장 결합강도에 미치는 영향)

  • Cho, Young-Gon;Lee, Young-Gon;Kim, Jong-Uk;Park, Byung-Cheul;Kim, Jong-Jin;Choi, Hee-Young;Jin, Cheul-Hee;Yoo, Sang-Hoon
    • Restorative Dentistry and Endodontics
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    • v.29 no.5
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    • pp.430-438
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    • 2004
  • This study evaluated the influence of application time of self-etching primers on microtensile bond strength (${\mu}$TBS) to dentin using three self-etching primer adhesive systems. Dentin surfaces were exposed from forty-eight human molars. They were conditioned with three self-etching primers (Clearfil SE Bond [SE], Unifil Bond [UF], Tyrian SPE + One Step Plus [TY]) and different primining times (10s, 20s, 30s and 40s). Composite resins were bonded to dentin surfaces and specimens were made. ${\mu}TBS$ was tested and statistically compared using by one-way ANOVA and Tukey's Test. The results of this study presented that priming time for 10s in SE and UF groups and for 30s and 40s in TY group was highly decreased ${\mu}TBS$ to dentin.

COMPARISON OF MICROLEAKAGE OF NEW GENERATION DENTIN BONDING SYSTEM (자가부식 전처치제를 이용한 상아질 결합재의 미세 누출에 관한 연구)

  • Kim, Jong-Soo
    • Journal of the korean academy of Pediatric Dentistry
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    • v.26 no.1
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    • pp.53-61
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    • 1999
  • Newley developed dentin bonding system which contains self-etching primer performed the removing of smear layer and etching procedure at once. So, it make possible more simple and shorter working time, the stronger bonding strength than conventional dentin bonding system. Cavities were prepared in the buccal and lingual surface of 30 extracted primary molars, and randomly assigned into three equal groups of 10 each. All cavities were filled with Z-100 composite resin following manufacturer's specifications after priming of three different dentin bonding system. Specimens stored for 7 days in 37 degree C water, thermocycled for 1000 cycles between 5 degree C and 55 degree C, immersed in 50% silvernitrate solution for 24 hours, and embedded in resin before being sectioned longitudinally. Data were analyzed by t-test and ANOVA. Mac-Bond II and Clearfil Linear-Bond II showed less microleakage at the occlusal and gingival margins compared to Scotchbond Multi Purpose. All dentin bonding systems showed significantly less microleakage at the occlusal margins compared to the gingival margins. But, there were no significantley difference between each group.

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Devloping Chcory for Forage Crop by New Technology (새로운 기법에 의한 치코리 (Cichorium intybus L.) 의 사료화에 관한 연구)

  • 허삼남;박홍석
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.15 no.4
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    • pp.265-273
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    • 1995
  • Seeds of chicory were collected and selected with good germination, emergence and productivity. To develop chicory as a new forage crop seeds were primed with polyethylene glycol (PEG 6000) and coated with some chemicals, and tested in laboratory and field. The results obtained are summarized as follows: 1. Among the seed lines collected, PUlgAH, PU21TH, PU37CH and PU30TK were germinated more quickly and took less time for germination than the others. 2. PUI8AH was the best in emergence and growth although PU21TH showed superior germinative ability among the lines collected. 3. Chicory seeds primed with 20~25% PEG solution for three days at $10^{\circ}C$, or the seeds treated with 25% PEG solution at $15^{\circ}C$ regardless the treatment period showed good germination performances. 4. Osmotic priming with PEG accelerated the germination of chicory, but not in the field. 5. Coated seeds geminated more slowly in Petridishes but showed superior emergence and growth to those of primed or untreated seeds. Treatment 3 showed the best performances in pot experiment. 6. Coated seeds showed remarkable increase in establishment and dry matter yield especially in sod sowing compared to the other sowing method. 7. Most nutrient contents except iron and manganese of chicory were much higher than those of mixed pasture .

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Clinical Study of the Effect of Aprotinin for Hemostasis in Open Heart Surgery (개심술시 Aprotinin의 지혈효과에 관한 임상적 고찰)

  • 정성운;김종원
    • Journal of Chest Surgery
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    • v.32 no.4
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    • pp.364-367
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    • 1999
  • Background: The efficacy of the hemostasis of prophylactic aprotinin after cardiac valve replacement was evaluated from January 1994 to December 1996 at Pusan National University Hospital. Material and Method: In a randomized study, 20 patients received aprotinin(2${\times}$106 KIU as a loading dose for 30 minutes after anesthesia, 1${\times}$106 KIU for priming and 5${\times}$105 KIU/hr as a maintenance dose from the completion of loading dose till skin closure) and another 20 untreated patients served as controls. Result: Aprotinin produced a significant reduction in postoperative blood loss compared with controls and significantly decreased total exposure to allogenic blood products compared with the control group(p<0.05). Conclusion: We conclude that aprotinin effectively reduces postoperative blood loss and trasfusion in patient undergoing cardiac valve replacement.

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Knowledge Representation Characteristics of Categories and Scripts: An Investigation on Hierarchy and Typicality Effects (개념지식의 유형에 따른 표상차이: 범주와 각본의 위계성과 전형성 비교1))

  • 이재호;이정모
    • Korean Journal of Cognitive Science
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    • v.11 no.3_4
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    • pp.73-81
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    • 2000
  • This study was conducted to investigate some characteristics of representation of category knowledge and script knowledge. Using primed lexical decision task with higher level primers in the representation structure, Experiment 1 examined the interaction effects between knowledge type and concept typicality. It was found that the concept typicality has some effects in category representation, while it has no significant effect in script representation. In Experiment 2, primers of the lower hierarchy in the representation structure were employed. The results showed that the main effect of knowledge type was significant: the response time for category knowledge was faster than that for script knowledge. Typicality effect did not show in this experiment. The results of t the two experiments suggest that category knowledge is represented in hierarchy and typicality. while script knowledge may lack in that characteristics. Other aspects of the differences in characteristics of category- and script- knowledge representation were discussed,

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Clinical experience of open heart surgery -500 cases- (개심술 500예에 대한 임상적 고찰)

  • 정황규
    • Journal of Chest Surgery
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    • v.19 no.4
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    • pp.633-643
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    • 1986
  • Five hundred cases of open heart surgery were operated in the Dept. of Thoracic and Cardiovascular Surgery, Pusan National University Hospital from July, 1981 to October, 1986. The clinical data were summarized as follows: 1. The age distribution of congenital heart disease patients was 2 to 41 years old and mean age was 13.4 years and of acquired heart disease was 11 to 57 years old and mean age was 32.7 years. 2. There were 319 cases [63.8%] of acyanotic congenital heart anomalies, 56 cases [11.2%] of cyanotic anomalies and 125 cases [25.[%] of acquired heart disease. 3. For myocardial protection, Bretschneider and potassium glucose solution had been used as cardioplegic solution and since 1983, GIK solution is being used repeatedly every 30 to 40 minutes time interval with excellent results. 4. The ingredient of the priming solution is Hartmann`s solution, mannitol, sodium bicarbonate, potassium, chloride, fresh ACD whole blood, calcium chloride, heparin and dexamethasone. 5. There were 94 cases of mild hypothermia, 280 cases of moderate hypothermia and 126 cases of intermediate hypothermia. 6. The overall mortality was 8.2%. And the mortality rate in each disease entity is 2.5% in acyanotic congenital cases, 33.9% in cyanotic congenital cases and 11.2% in acquired heart disease.

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The Clinical Experience of 610 Cases Open Heart Surgery (개심술 610례에 관한 임상적 고찰)

  • 정황규
    • Journal of Chest Surgery
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    • v.21 no.1
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    • pp.36-47
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    • 1988
  • 610 cases of open heart surgery was performed in the Department of Thoracic and Cardiovascular Surgery, Pusan National University Hospital from July 1981 to September 1987. The clinical data was summarized as follows: 1. The age distribution of congenital heart surgery patients was 2 to 41 years old [mean; 13.2 years] and surgery for acquired heart disease was 10 to 57 years old [mean: 32.8 years]. 2. There were 389 cases [63.8%] of acyanotic congenital heart anomalies, 63 cases [10.3%] of cyanotic congenital anomalies and 158 cases [25.9%] of acquired heart disease. 3. For myocardial protection, Bretschneider and potassium glucose solution had been used as cardioplegic solution and then since 1983, GIK solution has been used with repeated infusion method once for every 20 to 30 minutes of time interval after starting initial cardioplegia during operation with excellent results. 4. The ingredient of the priming solution is Hartmann`s solution, sodium bicarbonate, mannitol, potassium chloride, fresh ACD whole blood, calcium chloride, heparin and dexamethasone. 5. There were 96 cases [15.7%] of mild hypothermia, 333 cases [54.6%] of moderate hypothermia and 181 cases [29.7%] of intermediate hypothermia. 6. The mortality rate was 2.3% [9 out of 389 cases] in acyanotic congenital heart disease, 36.5% [23 out of 63 cases] in cyanotic congenital heart disease and 10.8% [17 out of 158 cases] in acquired heart disease, with overall mortality rate of 8.0% [49 out of 610 cases].

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An Analysis of the Status of Local Currency (Daedeok e-Loom) for the Vitality of Local Commercial Areas and an Empirical Study on the Direction of Development

  • Tae-Chang RYU
    • Journal of Distribution Science
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    • v.21 no.12
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    • pp.127-140
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    • 2023
  • Purpose: In a situation where the local economy and alley economy are stagnant, efforts to revitalize the role of small business owners need a virtuous cycle system through consumers' consumption power, not just cash support. Research design, data, and methodology: The study site focuses on Daedeok-gu, the first to introduce local currency as a policy. In the case of the store survey, 254 stores out of 300 stores registered with local currency were analyzed, and the consumer survey was conducted on 1,394 out of 1,500 local people using local currency. Statistical analysis was performed using the SPSS. Result: As a result of time-series checking whether local economic activities are carried out smoothly due to the nature of the local currency, the average daily sales of Daedeok-gu increased by 388,980won compared to 2019. This proved through empirical research in the region that local currency played a priming role in bringing opportunities and rehabilitation to the local commercial districts and small business owners. Conclusions: In the monetary function of simply buying and selling value through payment, points supported as incentives can be used as local currency while inducing direct participation in solving social problems, and the concurrent effect of causing problem-solving and regional economic vitality began to sprout.

Affective Priming Effect on Cognitive Processes Reflected by Event-related Potentials (ERP로 확인되는 인지정보 처리에 대한 정서 점화효과)

  • Kim, Choong-Myung
    • The Journal of the Korea Contents Association
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    • v.16 no.5
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    • pp.242-250
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    • 2016
  • This study was conducted to investigate whether Stroop-related cognitive task will be affected according to the preceding affective valence factored by matchedness in response time(RT) and whether facial recognition will be indexed by specific event-related potentials(ERPs) signature in normal person as in patients suffering from affective disorder. ERPs primed by subliminal(30ms) facial stimuli were recorded when presented with four pairs of affect(positive or negative) and cognitive task(matched or mismatched) to get ERP effects(N2 and P300) in terms of its amplitude and peak latency variations. Behavioral response analysis based on RTs confirmed that subliminal affective stimuli primed the target processing in all affective condition except for the neutral stimulus. Additional results for the ERPs performed in the negative affect with mismatched condition reached significance of emotional-face specificity named N2 showing more amplitude and delayed peak latency compared to the positive counterpart. Furthermore the condition shows more positive amplitude and earlier peak latency of P300 effect denoting cognitive closure than the corresponding positive affect condition. These results are suggested to reflect that negative affect stimulus in subliminal level is automatically inhibited such that this effect had influence on accelerating detection of the affect and facilitating response allowing adequate reallocation of attentional resources. The functional and cognitive significance with these findings was implied in terms of subliminal effect and affect-related recognition modulating the cognitive tasks.