• Title/Summary/Keyword: External Pressure

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독창적 아이디어에서 창조적 혁신까지 : 인공씨감자 기술혁신 성공사례 분석

  • 현재호
    • Proceedings of the Technology Innovation Conference
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    • 1997.07a
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    • pp.222-223
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    • 1997
  • By analyzing the successful innovation case of potato microtuber mass production technology, a representative case of technology-push type creative innovation in an imitation oriented research culture, this paper attempts to figure out conceptual model of creative innovation that is initiated by the public laboratories in catching-up country, Stages of creative innovation can be divided into the internal R&D stage and the external commercialization stage. Success of the internal R&D stage depended on autonomy to secure creative research idea and commitment of individual researchers. Psychological pressure evoked from sportlights of mass media and commitment of sponsor increased the intensity of research efforts of the researcher Recognition of research problem and its significance was intensified by site visits of agricultural fields, and the recognized higher impacts of expected research results and knowledge creation achieved were a fundamental source of self-motivation. In the stage of commercialization stage, various legal, socio-economic, and psychological barriers were confronted. In a catching-up country lacking of experiences of creative innovation, creative innovation process can be regarded as a barrier elimination and cultural revolution process. Among the barriers, psychological refusal of farmers to corn-sized potato seeds was critical, which finally enforced to further researches to enlarge the size of potato seeds. In addition, the researcher has concentrated his research efforts in one specialized research area by getting a series of similar research project funds rather than diversification. It was lucky for him to have a chance to carry out a series of similar researches in one research area during the last 10 years. In getting research funds from government and private companies continuously in one research area, both internal and external promoters played significant roles.

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Enhancement of Fermentative Hydrogen Production by Gas Sparging (기체 sparging에 의한 수소 발효의 효율 향상)

  • Kim, Dong-Hoon;Han, Sun-Kee;Kim, Sang-Hyoun;Bae, Byung-Uk;Shin, Hang-Sik
    • Journal of the Korea Organic Resources Recycling Association
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    • v.12 no.1
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    • pp.49-57
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    • 2004
  • The effect of gas sparging on continuous fermentative $H_2$ production was investigated using external gases ($N_2$, $CO_2$) with various flow rates (100, 200, 300, 400 ml/min). Gas sparging showed a higher $H_2$ yield than no sparging, indicating that the decrease of $H_2$ partial pressure by gas sparging had a good effect on $H_2$ fermentation. Especially, $CO_2$ sparging was more effective in the reactor performance than $N_2$ sparging. The composition of butyrate, the main metabolic product of $H_2$ fermentation by Clostridium sp., was much higher in $CO_2$ sparging. $H_2$ production increased with increasing flow rate only in $CO_2$ sparging. The best performance was obtained by $CO_2$ sparging at 300 ml/min, resulting in the highest $H_2$ yield of 1.65 mol $H_2/mol$ hexoseconsumed and the maximum $H_2$ production of 6.77 L $H_2/g$ VSS/day. Compared to $N_2$ sparging, there could be another beneficial effect in $CO_2$ sparging apart from lowering down the $H_2$ partial pressure. High partial pressure of $CO_2$ had little effect on $H_2$ producing bacteria but inhibitory effect on other microorganisms like lactic acid bacteria and acetogens which were competitive with $H_2$ producing bacteria.

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Impact of Weather on Prevalence of Febrile Seizures in Children (소아의 열성경련에 날씨가 미치는 영향)

  • Woo, Jung Hee;Oh, Seok Bin;Yim, Chung Hyuk;Byeon, Jung Hye;Eun, Baik-Lin
    • Journal of the Korean Child Neurology Society
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    • v.26 no.4
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    • pp.227-232
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    • 2018
  • Purpose: Febrile seizure (FS) is the most common type of seizure in children between 6 months to 5 years of age. A family history of febrile seizures can increase the risk a child will have a FS. Yet, prevalence of FS regarding external environment has not been clearly proved. This study attempts to determine the association between prevalence of FS and weather. Methods: This study included medical records from the Korea National Health Insurance Review and Assessment Service. Data were collected from 29,240 children, born after 2004, diagnosed with FS who were admitted to one of the hospitals in Seoul, Korea, between January 2009 and December 2013. During the corresponding time period, data from the Korea Meteorological Administration on daily monitoring of four meteorological factors (sea-level pressure, amount of precipitation, humidity and temperature) were collected. The relationships of FS prevalence and each meteorological factor will be designed using Poisson generalized additive model (GAM). Also, the contributory effect of viral infections on FS prevalence and weather will be discussed. Results: The amount of precipitation was divided into two groups for comparison: one with less than 5 mm and the other with equal to or more than 5 mm. As a result of Poisson GAM, higher prevalence of FS showed a correlation with smaller amount of precipitation. Smoothing function was used to classify the relationships between three variables (sea-level pressure, humidity, and temperature) and prevalence of FS. FS prevalence was correlated with lower sea-level pressure and lower humidity. FS prevalence was high in two temperature ranges (-7 to $-1^{\circ}C$ and $18-21^{\circ}C$). Conclusion: Low sea-level pressure, small amount of precipitation, and low relative air humidity may increase FS prevalence risk.

Stand-alone Real-time Healthcare Monitoring Driven by Integration of Both Triboelectric and Electro-magnetic Effects (실시간 헬스케어 모니터링의 독립 구동을 위한 접촉대전 발전과 전자기 발전 원리의 융합)

  • Cho, Sumin;Joung, Yoonsu;Kim, Hyeonsu;Park, Minseok;Lee, Donghan;Kam, Dongik;Jang, Sunmin;Ra, Yoonsang;Cha, Kyoung Je;Kim, Hyung Woo;Seo, Kyoung Duck;Choi, Dongwhi
    • Korean Chemical Engineering Research
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    • v.60 no.1
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    • pp.86-92
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    • 2022
  • Recently, the bio-healthcare market is enlarging worldwide due to various reasons such as the COVID-19 pandemic. Among them, biometric measurement and analysis technology are expected to bring about future technological innovation and socio-economic ripple effect. Existing systems require a large-capacity battery to drive signal processing, wireless transmission part, and an operating system in the process. However, due to the limitation of the battery capacity, it causes a spatio-temporal limitation on the use of the device. This limitation can act as a cause for the disconnection of data required for the user's health care monitoring, so it is one of the major obstacles of the health care device. In this study, we report the concept of a standalone healthcare monitoring module, which is based on both triboelectric effects and electromagnetic effects, by converting biomechanical energy into suitable electric energy. The proposed system can be operated independently without an external power source. In particular, the wireless foot pressure measurement monitoring system, which is rationally designed triboelectric sensor (TES), can recognize the user's walking habits through foot pressure measurement. By applying the triboelectric effects to the contact-separation behavior that occurs during walking, an effective foot pressure sensor was made, the performance of the sensor was verified through an electrical output signal according to the pressure, and its dynamic behavior is measured through a signal processing circuit using a capacitor. In addition, the biomechanical energy dissipated during walking is harvested as electrical energy by using the electromagnetic induction effect to be used as a power source for wireless transmission and signal processing. Therefore, the proposed system has a great potential to reduce the inconvenience of charging caused by limited battery capacity and to overcome the problem of data disconnection.

A Study on Comparison of Outdoor Wind Pressure Performance According to Outdoor Exposure and Acceleration Deterioration Methods of Structural Sealants Applied to Curtain Wall (커튼월에 적용된 구조용 실링재의 옥외폭로와 실내복합열화 처리방법에 따른 내풍압성능 비교연구)

  • Jang, Pil Sung;Hong, Soon Gu;Kim, Sung Rae
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.9
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    • pp.279-287
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    • 2018
  • Sealants are an important element of modern architecture and serve as a building protection against weathering by providing barriers against ingress of moisture, air, and other materials. Exposure to a variety of environments often reduces lifespan due to changes in physical, chemical and mechanical characteristics, and UV, humidity, and temperature expansion are important issues that are directly related to durability. In this study, a combined deterioration test chamber was developed to simulate the environment of the open air as an instrument for verifying the durability of structural sealing materials indoors. In order to replicate special weather conditions, such as yellow dust, acid rain, and contamination by microorganisms, it was deemed impossible to replicate the outdoor environment by 100 %, and the results of the results of the results of the external exposure test of the structural sealant and the combined deterioration testing device. As a result of the displacement test of the outdoor exposure test, it was determined that the sealant was breaking apart and that it would be smooth, and the displacement would be up to three times greater than the initial material value of 1 year. The displacement test results of the combined deterioration test device show the tendency to deteriorate, decreasing the elasticity and tensile characteristics. In the case of denatured silicon, the current 400 cycles have been completed to confirm 12 months of degradation of the external exposure. The deformation of the test specimen cannot be verified with the naked eye, so it is considered that the conditions of the specimen are more stable than the silicon sealant. As a result of the outdoor exposure test, if the combined deterioration test device is structured and proposed in the relevant guidance or specification, the anticipated lifespan of 12 months in the actual use environment can be verified indoors and below 3 months later, economically.

Rock Slope Stability Investigations Conducted on the Road Cut in Samrangjin-Miryang Area (삼량진-밀양 지역에 위치한 도로 절취사면에 대한 사면안정 연구)

  • Um Jeong-Gi;Kang Taeseung;Hwang Jin Yeon
    • Economic and Environmental Geology
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    • v.38 no.3 s.172
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    • pp.305-317
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    • 2005
  • This study addresses the preliminary results of rock slope stability analyses including hazard assessments for slope failure conducted on the selected sections of rural road cut slope which are about 4 km long. The study area is located in the Mt. Chuntae northeast of Busan and mainly composed of Cretaceous rhyolitic ash-flow tuff', fallout tuff, rhyolitc and andesite. The volcanic rock mass in the area has a number of discontinuities that produce a potentially unstable slope, as the present cut slope is more than 70 degrees in most of the slope sections. Discontinuity geometry data were collected at selected 8 scanline sections and analyzed to estimate important discontinuity geometry parameters to perform rock slope kinematic and block theory analyses. Kinematic analysis for plane sliding has resulted in maximum safe slope angles greater than $65^{\circ}$ for most of the discontinuities. For most of the wedges, maximum safe cut slope angles greater than $45^{\circ}$ were obtained. Maximum safe slope angles greater than 80" were obtained fur most of the discontinuities in the toppling case. The block theory analysis resulted in the identification of potential key blocks (type II) in the SL4, SL5, SL6 and SL8 sections. The chance of sliding taking place through a type ll block under a combined gravitational and external loading is quite high in the investigated area. The results support in-field observations of a potentially unstable slope that could become hazardous under external forces. The results obtained through limit equilibrium slope stability analyses show how a stable slope can become an unstable slope as the water pressure acting on joints increases and how a stable slope under Barton's shear strength criterion can fail as the worst case scenario of using Mohr-Coulomb criterion.

Evaluation of Consumer Nutrition Education Program to Reduce Sodium Intake Based on Social Cognitive Theory (사회인지론에 근거한 나트륨 섭취 줄이기 소비자 영양교육 프로그램의 효과 평가)

  • Ahn, So-Hyun;Kwon, Jong Sook;Kim, Kyung Min;Yoon, Jin-Sook;Kim, Hye-Kyeong
    • Korean Journal of Community Nutrition
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    • v.20 no.6
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    • pp.433-446
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    • 2015
  • Objectives: This study was performed to evaluate the consumer education program for reducing sodium intake based on social cognitive theory (SCT) and investigate consumer perceptions of environmental, cognitive and behavioral factors. Methods: Consumers (n=4,439) were recruited nationwide in Korea to participate in a nutrition education program for reducing sodium intake which was targeted on senior housewives (SH), parents (P), and office workers (OW). Questions regarding main factors of SCT were asked both before and after the education program. Results: SH and P recognized external social efforts and information to reduce sodium including nutrition labeling more than OW. The main barriers to practice reducing sodium intake were limited choice of low sodium food and menu, interference with social relationship when dining with others, and limited information, knowledge and skills. SH had lower barriers to practice reducing sodium intake and OW perceived 'preference to soup or stew' and 'preference to Kimchi, salted fish and fermented sauces' as barriers more than other groups at the baseline. Less than 50% of participants knew the relationship between sodium and salt, sodium in nutrition labeling, and recommended sodium intake. In addition, OW had little knowledge for capability to reduce sodium intake and lower self-efficacy to practice compared with SH and P. After education, positive outcome expectations such as lowering blood pressure, prevention of cardiovascular disease and osteoporosis were increased and barriers to practice reducing sodium intake were decreased in all groups (p < 0.05). The knowledge for behavioral capability and self-efficacy to reduce sodium intake were also improved but OW had still lower scores compared with other groups. Conclusions: These results suggested that nutrition education programs could be an effective tool to impact general population by facilitating awareness and increased capability to reduce sodium intake.

Effect of Thermal Treatments on Flavonoid Contents in Domestic Soybeans (국내산 대두(Glycine max. Merr)자원의 플라보노이드 대사체 동정 및 열처리 효과)

  • Shin, Jae-Hyeong;Kim, Heon-Woong;Lee, Min-Ki;Jang, Ga-Hee;Lee, Sung-Hyen;Jang, Hwan-Hee;Hwang, Yu-Jin;Park, Keum-Yong;Song, Beom-Heon;Kim, Jung-Bong
    • Korean Journal of Environmental Agriculture
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    • v.34 no.2
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    • pp.105-110
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    • 2015
  • BACKGROUND: Soy isoflavones, structurally similar to endogenous estrogens, may affect human body through both hormonally mediated and non-hormonally related mechanisms. Heat processing could change chemical compositions. The effects of different thermal processes, boiling and HTHP(high temperature and high pressure) on the composition of isoflavone compounds and total amount of domestic soybeans were investigated in this study. METHOD AND RESULTS: Three different kinds of soybean samples were collected from RDA-Genebank. The samples were extracted using methanol, distilled water, and formic acid based solvent. Also the same solvents were used for mobile phase in UPLC/ToF/MS. All of the isoflavone compounds were analyzed based on the aglycone type of external standard for quantification. The standard calibration curve presented linearity with the correlation coefficient R2 > 0.98, analysed from 1 to 50 ppm concentration. The total isoflavone contents does not change by treatment within the same breed. While "boiling" and "HTHP" processes tend to increase the contents of aglycone and ${beta}$-glucosides, "fresh" soybeans retained the high concentration of malonylglucosides. CONCLUSION: These results have to be considered while developing an effective functional food, from the health while point of view using soybeans.

Effect of Tyvex Mulching and Trickle Irrigation on Fruit Quality in Satsuma Mandarin (Citrus unshiu Mark.) (온주밀감의 과실 품질에 미치는 타이벡 멀칭 및 점적관수의 효과)

  • Han, Sang-Heon;Kang, Hoon;Chae, Chi-Won
    • Horticultural Science & Technology
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    • v.32 no.1
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    • pp.18-25
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    • 2014
  • This study was conducted to investigated effects of water relation of mulching and trickle irrigation on the external and internal fruit quality in Satsuma mandarin grafted on trifoliate orange rootstock in a orchard assigned to randomly three groups; whole period of Tyvex mulching (TM), Tyvex mulching with trickle irrigation once a week from October 22 to harvesting season (WM) and non-mulching treatment (NM). The average soil moisture content in the TM was lower than the WM during the time of trickle irrigation from Oct. 21 to Nov. 28. The leaf water potential was at the level of ${\Psi}max$ of -1.5 to -2.5 MPa during whole period of Tyvex mulching treatment but gradually increased at the point of supplement of water. The water and osmotic potential in juice vesicle was decreased by drought but increased again in response to the supply of water in WM. The total soluble solids (TSS) in fruit juice was increased by drought stress, but diminished in response to supply of water after drought. The content of titratible acidity was increased by drought stress but gradually decreased due to supplement of water after drought, reached it at the level of 1%. It was suggested that the accumulation of the total soluble solids compensates the degree of active osmoregulation and the decrease in content of acidity accounts for the fast respiration and water uptake resulted of the water after drought.

Morphology Control of Nanostructured Graphene on Dielectric Nanowires

  • Kim, Byeong-Seong;Lee, Jong-Un;Son, Gi-Seok;Choe, Min-Su;Lee, Dong-Jin;Heo, Geun;Nam, In-Cheol;Hwang, Seong-U;Hwang, Dong-Mok
    • Proceedings of the Korean Vacuum Society Conference
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    • 2012.08a
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    • pp.375-375
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    • 2012
  • Graphene is a sp2-hybridized carbon sheet with an atomic-level thickness and a wide range of graphene applications has been intensely investigated due to its unique electrical, optical, and mechanical properties. In particular, hybrid graphene structures combined with various nanomaterials have been studied in energy- and sensor-based applications due to the high conductivity, large surface area and enhanced reactivity of the nanostructures. Conventional metal-catalytic growth method, however, makes useful applications difficult since a transfer process, used to separate graphene from the metal substrate, should be required. Recently several papers have been published on direct graphene growth on the two dimensional planar substrates, but it is necessary to explore a direct growth of hierarchical nanostructures for the future graphene applications. In this study, uniform graphene layers were successfully synthesized on highly dense dielectric nanowires (NWs) without any external catalysts. We also demonstrated that the graphene morphology on NWs can be controlled by the growth parameters, such as temperature or partial pressure in chemical vapor deposition (CVD) system. This direct growth method can be readily applied to the fabrication of nanoscale graphene electrode with designed structures because a wide range of nanostructured template is available. In addition, we believe that the direct growth growth approach and morphological control of graphene are promising for the advanced graphene applications such as super capacitors or bio-sensors.

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