• Nuclear Engineering and Technology
• /
• v.40 no.6
• /
• pp.451-458
• /
• 2008

After more than 10 years construction, KSTAR (Korea Superconducting Tokamak Advanced Research) had finally completed its assembly in June 2007, and then achieved the goal of first-plasma in July 2008 through the four month's commissioning. KSTAR was constructed with fully superconducting magnets with material of $Nb_3Sn$ and NbTi, and their operation temperatures are maintained below 4.5K by the help of Helium Refrigerator System. During the first-plasma operation, plasmas of maximum current of 133kA and maximum pulse width of 865ms were obtained. The KSTAR Integrated Control System (KICS) has successfully fulfilled its missions of surveillance, device operation, machine protection interlock, and data acquisition and management. These and more were all KSTAR commissioning requirements. For reliable and safe operation of KSTAR, 17 local control systems were developed. Those systems must be integrated into the logically single control system, and operate regardless of their platforms and location installed. In order to meet these requirements, KICS was developed as a network-based distributed system and adopted a new framework, named as EPICS (Experimental Physics and Industrial Control System). Also, KICS has some features in KSTAR operation. It performs not only 24 hour continuous plant operation, but the shot-based real-time feedback control by exchanging the initiatives of operation between a central controller and a plasma control system in accordance with the operation sequence. For the diagnosis and analysis of plasma, 11 types of diagnostic system were implemented in KSTAR, and the acquired data from them were archived using MDSpius (Model Driven System), which is widely used in data management of fusion control systems. This paper will cover the design and implementation of the KSTAR integrated control system and the data management and visualization systems. Commissioning results will be introduced in brief.

• Korean Journal of Plant Resources
• /
• v.23 no.4
• /
• pp.360-367
• /
• 2010

The genetic diversity and structure of P. tongkangensis in 5 populations from 3 regions was investigated using 56 markers derived from 6 ISSR primers. Genetic diversity at the species level (P=94.6, SI=0.377, h=0.240) was substantial considering the limited distribution and small size of populations. Genetic differentiation among regions (12%) and among populations (13%) in the region was not clearly evident, which suggested a moderate level of gene flow among adjacent populations. The Mantel test revealed a significant correlation between genetic differentiation (${\Phi}_{ST}$) and geographic distance among populations. This was supported by cluster analysis and principal coordinate analysis (PCoA). The significant difference in marker band frequency at many loci and their fixation in opposite directions in the smallest and most isolated population SC were considered due to genetic drift. Therefore, the genetic diversity of P. tongkangensis could be compromised if the distribution area or the size of the population was further reduced. In particular, small and isolated populations could be at great risk of extinction. Considering this, the unique habitats of P. tongkangensis should be protected and the reduction of population size should be closely monitored. Conservation efforts including the seeding and planting of seedlings should be done carefully based on their genetic and ecological traits. Our data support the argument that establishing an integrated management system for the efficient conservation of P. tongkangensis is critical.

• KIPS Transactions on Computer and Communication Systems
• /
• v.7 no.7
• /
• pp.165-174
• /
• 2018

The purpose of this study is to verify the effects of R&D process maturity on product development performance and to verify whether R&D project performance mediating effect. The questionnaire was collected and analyzed to 131 persons related to the R&D work in 55 companies and public institutions performing R&D work. The results of this study are as follows, the effect of R&D process maturity on product development performance and mediating effect of R&D project performance were analyzed by simple and multiple regression analysis. Regression analysis was analyzed by SPSS statistical program. The higher the maturity level of the R&D process, the higher the product development performance and the R&D project performance, and the R&D project performance is partially mediated. It is concluded that it is important to establish and operate a systematic R&D process and to develop a project management methodology suitable for the characteristics of a company in order to improve product development performance. It is expected that if this study are utilized as practical R&D management methodology in corporate management, it will contribute to improvement of company product performance.

• Proceedings of the Korean Institute of Surface Engineering Conference
• /
• 2016.11a
• /
• pp.196-196
• /
• 2016

치과나 기공소로부터 높은 원가로 인한 재료선택에 어려움을 겪고 있어 귀금속 금합금의 물성을 가질 수 있도록 하면서 가격급등으로 인한 문제 해결하기 위한 비귀금속 합금으로 대체가 필요하기에 이에 따른 연구가 이루어져 국산 제품의 상품화를 위해 파라듐을 이용하여 적합한 새로운 합금을 개발하는 것이 필요하다. 치과용 골드합금은 미국치과의사 협회의 구정에 의하면 1형부터 4형까지 분류하고 있으며 3형에 해당하는 강도와 기계적인 특성을 갖도록 파라듐으로 대체하는 연구가 진행중이거나 시판되고 있다. 따라서 본 연구에서는 2형, 3형 및 4형을 대체가능하도록 팔라듐을 기반으로 한 새로운 합금을 설계하고 합금의 성분원 소인 Au(1~5), Pd(20~25), Ag(70~75), In(1.5) 및 Zn(2)등으로 조성을 변화시켜 측량 후 합금을 제조하기 위하여 아르곤 분위기하의 진공아크용해로를 이용하여 용해하였다. 정량된 금속을 진공아크 용해로에 장입하고 용해는 균질한 합금이 되도록 최소한 6회 이상 용융을 실시하며 합금성분의 손실이 발행하지 않도록 보정을 하였다. 합금의 미세조직 관찰을 위하여 샘플을 고속 다이아몬드 정밀 절단기(Acculom-5, STRUERS, Denmark)를 이용하여 절단한 후 2000 grit의 Sic 연마지에서 단계적으로 $0.3{\mu}m$ 알루미나 분말까지 연마한 후 초음파 세척을 하였다. 준비한 시편은 KCN과 $(NH_4)_2S_2O_8$을 1:1로 혼합한 부식액으로 에칭한 후 OM과 SEM을 이용하여 조직을 관찰하였으며 각 샘플의 성분변화는 EDS 분석을 통해 확인하고 결정구조는 XRD를 사용하여 분석하였다. 경도시험은 비커스경도시험기를 이용하여 5kg의 하중을 30초간 작동시켜 압흔을 연결된 micron으로 평균값을 측정하였다. 각 시편의 부식거동은 POTENTIOSTAT(Model PARSTAT 2273, EG&G, USA)을 이용하여 구강 내환경화 유사한 $36.5{\pm}1^{\circ}C$의 0.9% NaCl에서 실시하였다. 인가전위는 -1500mV에서 1000mV까지 1.67 mV/min의 주사속도로 인가하여 시험을 수행하였으며 분극곡선으로부터 부식전위와 부식전류밀도 및 부동태영역의 전류밀도로 금속의 용출거동을 조사하였으며 부식이 끝난 시편은 FE-SEM과 EDS를 사용하여 조사하였다. 기계적인 특성은 Pd-Ag에 3wt%의 Au를 첨가한 합금이 Pd-Ag에 1.5wt%합금을 첨가한 경우에 비하여 기계적인 특성이 증가하고 내식성이 크게 증가하였다. 이들 합금에 Cu를 11wt%를 첨가한 경우는 비커스경도가 200이상으로 높게 나타났지만 내식성이 크게 감소하였다.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
• /
• v.27 no.4
• /
• pp.313-318
• /
• 2016

Objective: The purpose of this study was to investigate the clinical utility of the Korean Wechsler Intelligence Scale for Children-Fourth Edition (K-WISC-IV) and General Ability Index (GAI) in children with attention-deficit hyperactivity disorder (ADHD). Methods: The GAI and Full Scale IQ (FSIQ) in K-WISC-IV were compared for a group of 79 children with ADHD and 234 normal children. The mean differences within each group were testified by the t-test and Cohen's d. The Wechsler's descriptive classifications for each GAI and FSIQ score were analyzed in the children with ADHD. Additionally, the critical value for the difference between the means of the FSIQ and GAI was calculated in the normal children. Results: The score on the GAI was higher than that on the FSIQ in the children with ADHD, with a mean difference of 2.19 points. The implications of these findings are discussed regarding the cognitive characteristics of the children with ADHD. According to Wechsler's descriptive classification, the application of the GAI showed a lower (7.59%), equal (61.65%) or higher (60.76%) prevalence of ADHD compared to the application of FSIQ. Conclusion: The implications of these findings are discussed regarding the cognitive characteristics of the children with ADHD. The GAI reflecting the attention and behavioral problems in children with ADHD could be utilized as an alternative global intelligence estimate that considers their potential for development.

• Journal of Acupuncture Research
• /
• v.21 no.6
• /
• pp.281-289
• /
• 2004

Objective : Blepharoptosis is drooping of eyelid which causes impairment of visual field by covering partially or completely, and it is classified into congenital ptosis and acquired one. In western medicine, idiopathic blepharoptosis is usually treated by tarsectomy. Contrary to that concept, we consider eyelid is assigned to Yookryoon(肉輪) among Ohryoon(五輪) which matches to spleen. In oriental medicine, it can be treated by promoting spleen and kidney. Here I report two cases of idiopathic blepharoptosis improved by conservative acupuncture therapy and herb medicine. Methods : The changes in clinical symptoms of general body weakness, anorexia, dizziness, dry eye, etc, in degree of eyelid drooping and in individual expression were described as they were treated with acupuncture therapy, herb medicine, Bojoong-ikgi-tang(補中益氣湯) and some physical therapy including Negative, I.C.T, S.S.P and Carbon. Results : Symptoms(ex) general body weakness, anorexia, dizziness, dry eye, etc) at admission improved and disappeared gradually with acupuncture therapy and herb medicine. The patients could discharge with favorable recovery. Conclusions : In oriental medicine, blepharoptosis is mainly treated by promoting Qihyul(氣血) and enhancing flow of that. If the patient has deficiency of Suhnchun-poomboo(先天稟褓賦) and Mungmoon-hwa(命門火), he is treated by promoting Shin-yang(腎陽). If he is weak in Bee-qi(脾氣), he needs to be treated by strengthening Bee-yang(脾陽) where patient with lack of Ganhyul(肝血) is supposed to be treated by promoting Hyul(血). These following two cases were managed by acupuncture, herb medicine and physical therapy on idiopathic blepharoptosis.

• International Journal of Oral Biology
• /
• v.35 no.4
• /
• pp.169-175
• /
• 2010

Cholinesterase (ChE) is one of the most ubiquitous enzymes and in addition to its well characterized catalytic function, the morphogenetic involvement of ChE has also been demonstrated in neuronal tissues and in non-neuronal tissues such as bone and cartilage. We have previously reported that during mouse tooth development, acetylcholinesterase (AChE) activity is dynamically localized in the dental epithelium and its derivatives whereas butyrylcholinesterase (BuChE) activity is localized in the dental follicles. To test the functional conservation of ChE in tooth morphogenesis among different species, we performed cholinesterase histochemistry following the use of specific inhibitors of developing molar and incisors in the hamster from embryonic day 11 (E11) to postnatal day 1 (P1). In the developing molar in hamster, the localization of ChE activity was found to be very similar to that of the mouse. At the bud stage, no ChE activity was found in the tooth buds, but was first detectable in the dental epithelium and dental follicles at the cap and bell stages. AChE activity was found to be principally localized in the dental epithelium whereas BuChE activity was observed in the dental follicle. In contrast to the ChE activity in the molars, BuChE activity was specifically observed in the secretory ameloblasts of the incisors, whilst no AChE activity was found in the dental epithelium of incisors. The subtype and localization of ChE activity in the dental epithelium of the incisor thus differed from those of the molar in hamster. In addition, these patterns also differed from the ChE activity in the mouse incisor. These results strongly suggest that ChE may play roles in the differentiation of the dental epithelium and dental follicle in hamster, and that morphogenetic subtypes of ChE may be variable among species and tooth types.

• Journal of the Korea Concrete Institute
• /
• v.20 no.4
• /
• pp.423-430
• /
• 2008

VES-LMC (very-early strength latex-modified concrete) has been widely used as repair material for bridge deck overlay or rehabilitation, because the overlaid or repaired could be opened to the traffic after 3 hours of curing. Although the field performance of VES-LMC generally indicates that it has an excellent bonding to the substrate and shows a long term performance, little quantitative data or research results have been presented in the literature on structural studies. The purpose of this study was to investigate the flexural behavior, interfacial performance, crack propagation, and strengthen effect of RC beam overlaid or repaired by VES-LMC through the 4-point flexural loading test. Two different types of RC beam were fabricated for repair and rehabilitation types. The test result showed that the strengthen effect, in term of flexural stiffness, increases as the depth of repair or overlay increases. More than 40% of stiffness was improved when the depth of repair was up to steel position. However, there was a little difference between 80 mm and 120 mm repaired beam. This means the repair depth must be considered. The interfacial behavior data showed that the repaired or overlaid beams had a little relative displacement. This means that two materials behave comparatively acting together. However, there were two specimens which had large displacement at the interface, because of poor bond strength. This suggested that interface treatment is one of the most important jobs in composite beams.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.31 no.2D
• /
• pp.323-334
• /
• 2011

In this study, we performed the residual geoid modeling using the FFT and LSC methods in context of application of R-R (Remove and Restore) technique as a general technique for gravimetric geoid model in order to propose the effective way of geoid determination in Korea. For this, a number of data compiled for residual geoid modeling by the multi-band spherical FFT method with Stoke's formula and LSC method as known as statistical method. The geometric geoidal heights obtained from 503 GPS/Levelling data were used for inducing the various elements and proper computation process which should be considered for improving the accuracy of residual geoid modeling. Finally, we statistically compared the results of residual geoid heights between FFT and LSC methods and reviewed then the proper way of residual geoid modeling to the region of Korea. As the results of comparison, LSC method is not suitable for residual geoid modeling in Korea due to the noise and lack of gravity observations and the effects of local characteristics, while FFT method by applying Stokes' integral with proper cap size and modified kernel which provides the better accuracy of residual geoid heights up to 10 cm more than those of LSC method.

• Journal of Korean Tunnelling and Underground Space Association
• /
• v.19 no.6
• /
• pp.1045-1058
• /
• 2017

This paper is a study on railway tunnel behavior characteristic of shallow overburden under the existing road. In order to understand the behavior characteristics of the ground deformation during tunnel excavation, a horizontal rod extensometers were installed in the passage area of the shallow overburden tunnel under the road, and the measurement and analysis were carried out. To compare the in situ measurement, three dimensional numerical analysis with ground condition and construction step was carried out using MIDAS NX. As a result of the field measurement, large preceding settlement occurred where the poor ground condition with shallow overburden excavation has been conducted. As a result of the numerical analysis, the largest settlement occurred at the shallow overburden point where the ground condition was poor. Therefore, in the shallow overburden section where the soil condition is poor and a sufficient depth can't be secured and the arching effect of the ground around the tunnel can't be expected, careful attention should be paid to the application of stiffness reinforcement measures and to minimize ground loosening.