• Proceedings of the Korean Geotechical Society Conference
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• 1999.03a
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• pp.209-216
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• 1999

Prefabricated piles used for construction of highway bridges are most of steel pipe piles and few of prestressed concrete piles. Its installation and inspection are less controllable and have much uncertainty due to changes in subsoil and groundwater conditions. However, most of these piles have been controlled using outdated pile driving formula such as Hiley's formula which models just the energy conservation due to its simple applicability in the field. This formula results in overstriking or sometimes understocking due to buckling of pile head. Engineers cannot ensure by the formula whether pile is installed properly. To compensate the drawbacks of excising pile formula, parameters in Hiley's formula and 55 formula are reviewed. Final sets used in pile formula and PDA test results(E.O.I.D) are measured during pile driving along the depth. These measured results along the depth were compared with each other and with N values, so that relations between the each result could be inferred. Also the factor of safety which can be used for pile driving formula are suggested.

• International Journal of Automotive Technology
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• v.5 no.3
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• pp.145-153
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• 2004

Potential fuel economy improvements and environmental legislation have renewed interest in Gasoline Direct Injection (GDI) engines. Computational models of fuel injection and mixing processes pre-ignition are being developed for engine optimisation. These highly transient thermofluid models require verification against temporally and spatially resolved data-sets. The authors have previously established the capability of PDA to provide suitable temporally and spatially resolved spray characteristics such as mean droplet size, velocity components and qualitative mass distribution. This paper utilises this data-set to assess the predictive capability of a numerical model for GDI spray prediction. After a brief description of the two-phase model and discretisation sensitivity, the influence of initial spray conditions is discussed. A minimum of 5 initial global spray characteristics are required to model the downstream spray characteristics adequately under isothermal, atmospheric conditions. Verification of predicted transient spray characteristics such as the hollow-cone, cone collapse, head vortex, stratification and penetration are discussed, and further improvements to modelling GDI sprays proposed.

• Journal of Veterinary Clinics
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• v.27 no.6
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• pp.740-745
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• 2010

Patent ductus arteiosus (PDA) is the persistent opening of ductus arterious located between pulmonary artery and descending aorta after birth. Although PDA can be occluded by surgical ligation, interventional closure of PDA using various devices is being rapidly replaced to surgical ligation, because of its non-invasive nature of treatment and minimal post-care after treatment. Main problem encountering in interventional treatment in toy breed dogs is vascular inaccessibility due to small size of artery. Although transvenous approach using jugular veins has been developed, this technique requires experienced skill to locate occlude devices into PDA and has high risk of accidental dislodgement of occluding devices (i.e. embolization coils or vascular plugs). Therefore, in this study, we developed a modified technique for coil embolization using mini-angiocatheter with trans-femoral approach in toy breed dogs (< 3.0 kg of body weight). With this modified method, we were successfully treated two toy breed (Maltese) dogs with the left to right shunted PDA.

• Asian Journal of Turfgrass Science
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• v.25 no.2
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• pp.160-170
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• 2011

Commercial formulation of fungicides was studied in vitro for sensitivity against Typhula species causal agents of Typhula blight. Efficacies of fungicides application, spray volume, nozzle types and fungicides applied time (early fall and late fall) were evaluated for their influence on the chemical control of Typhula blight of turfgrass during the winter season in Wisconsin. All fungicides effectively reduced the mycelial growth of eight isolates of Typhula spp. in vitro on potato dextrose agar (PDA) media. For inhibitory effects on mycelial growth of eight isolates, propiconazole was the most effective at $1.0{\mu}g$ active ingredient (a.i) / ml of PDA. Typhula incarnata two isolates were significantly more sensitive to all fungicides of PDA than six isolates of three varieties of T. ishikariensis. For 2 years in field experiment, unsprayed control has significantly more disease severity than seven fungicides were applied to field plots at two locations. Propiconazole was the most effective for controlling Typhula blight, at two locations in both years. The level of disease control was not dependent on fungicides spray volume or nozzle types at two locations. The disease damage treated with triadimefon applied time (early fall and late fall) was not significantly different at two location for two years.

• Journal of Ginseng Research
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• v.24 no.2
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• pp.53-57
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• 2000

Chlamydospores were isolated from hyphae of Cylindrocanon destmctans by homogenization and/or ultrasonic treatment. Rate of the isolated chlamydospores by the homogenization with glass tissue grinder were 9.8% of all total chlamydospores formed in the culture of C. destructans. The length of mycelial fragments after the homogenization was about 400㎛ They were, however, formed in clusters of the chlamydospores and the mycelia The rate of the isolated chlamydospores from additional ultrasonic treatment after the homogenization of the mycelia were 74.3%. The length of mycelial fragments with the ultrasonic treatment was about 20 fm and chlamydospores seemed to be isolated from the mycelial mats and dispersed evenly in the culture. The numbers of chlamydospore in a catena were 1 to 8 cells after the homogenization on potato dextrose agar (PDA). Meanwhile the numbers of them after added ultrasonic treatment were 1 to 4 cells. Germination percentages of the isolated chlamydospores from the ultrasonic treatment were 46.8% after incubation of 2 days on PDA at 20。C and 60.7% after incubation of 13 days at 5。C, respectively. Germination rate of chlamydospores to the total chlamydospores produced by the ultrasonic treatment was 55.8%. However, it was increased to 74% when it was measured in the germinated catenae to the total catenae.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2009.05a
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• pp.68-71
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• 2009

iATA(Internet Advanced Technology Attachment)는 TCP/IP 네트워크를 통해 원격의 대용량의 가상 저장 공간을 자신의 로컬 디스크 처럼 활용이 가능하게 하는 기술로 이는 모바일 기기(PDA, 휴대폰 등)와 같은 저장 공간의 부족문제를 가지고 있는 장치에 적용하여 저장 공간의 부족 문제를 근본적으로 해결할 수 있는 솔루션이라 할 수 있다. iATA는 SCSI 하드디스크가 장착된 시스템에서만 서버를 구축해야만 하는 iSCSI와는 달리 일반 가정이나 사무실에서 주로 사용하는 ATA 하드 디스크에도 서버 구축이 가능한 확장성을 가지고 있으며 이는 iATA의 최대 장점 중 하나라 할 수 있다. 또한, Web 사이트를 통해 많은 사람들이 iATA 서비스를 이용하여 자신의 모바일 기기에서의 저장공간 문제를 극복할 수 있으며, 최근 사회 문제로 크게 대두되고 있는 개인 정보 유출의 폐해를 막기 위해 개인 인증시 OpenSSL과 MD5를 이용한 보안/암호화 기법을 사용하여 개인 정보 유출에 의한 불이익 및 개인 정보 악용으로 인한 범죄를 막을 수 있다. 하지만, 기존의 iATA상에서는 디스크 관리가 서버에서만 가능하다는 문제점이 있다. 즉, 사용자만의 개인공간을 가질 수가 없다. 이처럼 개인 사진이나, 다이어리같은 정보들을 관리 할 수 없는 문제점을 해결하기 위해 클라이언트에서 자신만의 디스크 공간을 가질 수 있게 파티션을 할당해주고, 그 공간을 클라이언트만의 공간으로 만들어 주는 기술을 개발하는데 그 목적이 있다.

• 한국신재생에너지학회:학술대회논문집
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• 2010.06a
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• pp.51.2-51.2
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• 2010

Efficient and durable electrical energy storage is one of the major factors limiting the wide-spread adoption of renewable energy. Since lithium-ion batteries (LIBs) were first commercialized in the early 1990s, LIBs have emerged as an important energy storage device for portable electronics. LIBs are very desirable because of their high energy storage per volume and per mass. However, LIBs with high energy and power as well as higher stability are needed for their use in a variety of energy storage applications such as MEMS devices, PDA, plug-in hybrids, all-electric vehicles and large scale utility systems. In this talk, I will discuss present energy perspective, especially energy storage and its role in renewable energy. After that I will discuss the recent advances in nanostructured materials and interface engineering that have led to the achievement of improved Li-ion batteries. Finally I will talk aboutcritical issues that need to be addressed to obtain further improvements in Li-ion batteries.

• Proceedings of the Korean Information Science Society Conference
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• 2005.07a
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• pp.352-354
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• 2005

인터넷을 통하여 비디오, 오디오 등 미디어 데이터를 실시간으로 전승 받아 실시간으로 재생할 수 있는 기술은 미디어 데이터를 처리하는 클라이언트 측의 필수적인 기능으로 요구되고 있으며, PC 등의 데스크탑 뿐만 아니라 PDA, 핸드폰, 유무선 통신 단말기 등의 모바일 단말에서도 활용 범위를 넓혀가고 있다. 본 논문에서는 모바일 단말에 적합한 MPEG-4 기반의 다채널 실시간 미디어 데이터 처리 시스템을 설계하고, 4개의 채널로 입력되는 비디오 데이터를 서버로부터 전송받아 재생하는 Pocket PC 기반의 PDA용 MPEG-4 미디어 데이터 처리기를 구현한다. 본 처리기는 네트워크의 부하를 감소시키고, 모바일 단말의 자원 부족으로 인한 문제점을 해결하면서 실시간으로 전송되는 미디어 데이터를 처리한다.

• KSBB Journal
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• v.26 no.3
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• pp.229-236
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• 2011

An efficient screening method was developed for rapid selection of a few overproducers of itaconic acid (IA) among the great many mutants derived from mother strains of Aspergillus terreus. For this purpose, an attempt was made to reveal the relationships of the growth rate and sporulation of each mutant on PDA solid medium with its IA productivity in the final liquid production-culture. As a result, it was possible to classify the mutated strains into 5 groups (from [A] to [E] group) according to theirmorphologies (i.e., growth rate and sporulation extent) on the PDA slants. Notably, most of the high-yielding mutants of IA were observed to belong to [A]group which had the properties of the highest growth rate and sporulation among the 5 groups, whereas the mutant groups of [C], [D] and [E] with the contrasting morphological features showed significant reductions in their IA productivities. From these results, it was concluded that the probability of selecting IA overproducing mutants could be remarkably enhanced when the mutated colonies showing faster growth rates are firstly selected on the PDA plate, and then further screening process is performed on the basis of the sporulation extents of the mutants selected. Consequently, through the application of the strategy developed in this study, costs and time involvedin the labor-intensive task of strain improvement could be reduced to a great extent, because the time-consuming liquid culture processes did not need to performed for the unfavorable mutants belonging to the groups other than group [A].

• Clinical and Experimental Pediatrics
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• v.61 no.12
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• pp.397-402
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• 2018

Purpose: Transcatheter device closure of patent ductus arteriosus (PDA) is challenging in early infancy. We evaluated PDA closure in infants less than 6 months old. Methods: We performed a retrospective review of infants less than 6 months of age who underwent attempted transcatheter device closure in our institution since 2004. To compare clinical outcomes between age groups, infants aged 6-12 months in the same study period were reviewed. Results: A total of 22 patients underwent transcatheter PDA closure during the study period. Patient mean age was $3.3{\pm}1.5months$, and weight was $5.7{\pm}1.3kg$. The duct diameter at the narrowest point was $3.0{\pm}0.8mm$ as measured by angiography. The most common duct type was C in the Krichenko classification. Procedural success was achieved in 19 patients (86.3%). Major complications occurred in 5 patients (22.7%), including device embolization (n=1), acquired aortic coarctation (n=2), access-related vascular injury requiring surgery (n=1), and acute deterioration requiring intubation during the procedure (n=1). Two patients had minor complications (9.1%). Twenty-four infants aged 6-12 months received transcatheter device closure. The procedural success rate was 100%, and there were no major complications. The major complication rate was significantly higher in the group less than 6 months of age (P=0.045). There was a trend toward increased major complication and procedural failure rates in the younger age group (P<0.01). Conclusion: A relatively higher incidence of major complications was observed in infants less than 6 months of age. The decision regarding treatment modality should be individualized.