• Proceedings of the Korean Magnestics Society Conference
• /
• 2010.06a
• /
• pp.79-79
• /
• 2010

Semimetallic bismuth (Bi) has been extensively investigated over the last decade since it exhibits very intriguing transport properties due to their highly anisotropic Fermi surface, low carrier concentration, long carrier mean free path l, and small effective carrier mass $m^*$. In particular, the great interest in Bi nanowires lies in the development of nanowire fabrication methods and the opportunity for exploring novel low-dimensional phenomena as well as practical application such as thermoelectricity[1]. In this work, we introduce a self-assembled interconnection of nanostructures produced by an on-film formation of nanowires (OFF-ON) method in order to form a highly ohmic Bi nanobridge. A Bi thin film was first deposited on a thermally oxidized Si (100) substrate at a rate of $40\;{\AA}/s$ by radio frequency (RF) sputtering at 300 K. The sputter system was kept in an ultra high vacuum (UHV) of $10^{-6}$ Torr before deposition, and sputtering was performed under an Ar gas pressure of 2m Torr for 180s. For the lateral growth of Bi nanowires, we sputtered a thin Cr (or $SiO_2$) layer on top of the Bi film. The Bi thin films were subsequently put into a custom-made vacuum furnace for thermal annealing to grow Bi nanowires by the OFF-ON method. After thermal annealing, the Bi nanowires cannot be pushed out from the topside of the Bi films due to the Cr (or $SiO_2$) layer. Instead, Bi nanowires grow laterally as a mean s of releasing the compressive stress. We fabricated a self-assembled Bi nanobridge (d=192 nm) device in-situ using OFF-ON through annealing at $250^{\circ}C$ for 10hours. From I-V measurements taken on the Bi nanobridge device, contacts to the nanobridge were found highly ohmic. The quality of the Bi nanobridge was also proved by the high MR of 123% obtained from transverse MR measurements. These results manifest the possibility of self-assembled nanowire interconnection between various nanostructures for a variety of applications and provide a simple device fabrication method to investigate transport properties on nanowires without complex patterning and etching processes.

• Geophysics and Geophysical Exploration
• /
• v.7 no.3
• /
• pp.174-183
• /
• 2004

The knowledge of rock strength is important in assessing wellbore stability problems, effective sanding, and the estimation of in situ stress field. Numerous empirical equations that relate unconfined compressive strength of sedimentary rocks (sandstone, shale, and limestone, and dolomite) to physical properties (such as velocity, elastic modulus, and porosity) are collected and reviewed. These equations can be used to estimate rock strength from parameters measurable with geophysical well logs. Their ability to fit laboratory-measured strength and physical property data that were compiled from the literature is reviewed. While some equations work reasonably well (for example, some strength-porosity relationships for sandstone and shale), rock strength variations with individual physical property measurements scatter considerably, indicating that most of the empirical equations are not sufficiently generic to fit all the data published on rock strength and physical properties. This emphasizes the importance of local calibration before one utilizes any of the empirical relationships presented. Nonetheless, some reasonable correlations can be found between geophysical properties and rock strength that can be useful for applications related to wellhole stability where haying a lower bound estimate of in situ rock strength is especially useful.

• Proceedings of the Korean Society of Crop Science Conference
• /
• 2017.06a
• /
• pp.140-140
• /
• 2017

Nutritious and functional foods from crop have received great attention in recent years. Colored-grain wheat contains high phenolic compound and a large number of flavonoid. The anthocyanin and polyphenolic synthesis and accumulation is generally stimulated in response to biotic or abiotic stresses. Here, we analyzed genome wide transcripts in seedling of colored-grain wheat response to ABA and PEG treatment. About 900 and 1500 transcripts (p-value < 0.05) from ABA and PEG treatment were aligned to IWGSC1+popseq DB which is composed of over 110,000 transcripts including 100,934 coding genes. NR protein sequences of Poaceae from NCBI and protein sequence of transcription factors originated from 83 species in plant transcription factor database v3.0 were used for annotation of putative transcripts. Gene ontology analysis were conducted and KEGG mapping was performed to show expression pattern of biosynthesis genes related in flavonoid, isoflavonoid, flavons and anthocyanin biopathway. DroughtDB (http://pgsb.helmholtz-muenchen.de/droughtdb/) was used for detection of DEGs to explain that physiological and molecular drought avoidance by drought tolerance mechanisms. Drought response pathway, such as ABA signaling, water and ion channels, detoxification signaling, enzymes of osmolyte biosynthesis, phospholipid metabolism, signal transduction, and transcription factors related DEGs were selected to explain response mechanism under water deficit condition. Anthocyanin, phenol compound, and DPPH radical scavenging activity were measured and antioxidant activity enzyme assays were conducted to show biochemical adaptation under water deficit condition. Several MYB and bHLH transcription factors were up-regulated in both ABA and PEG treated condition, which means highly expressed MYB and bHLH transcription factors enhanced the expression of genes related in the biosynthesis pathways of flavonoids, such as anthocyanin and dihydroflavonols in colored wheat seedlings. Subsequently, the accumulation of total anthocyanin and phenol contents were observed in colored wheat seedlings, and antioxidant capacity was promoted by upregulation of genes involved in maintaining redox state and activation of antioxidant scavengers, such as CAT, APX, POD, and SOD in colored wheat seedlings under water deficit condition. This work may provide valuable and basic information for further investigation of the molecular responses of colored-grain wheat to water deficit stress and for further gene-based studies.

• Proceedings of the Korean Society of Crop Science Conference
• /
• 2017.06a
• /
• pp.141-141
• /
• 2017

The ubiquitin-proteasome pathway is the major regulatory mechanism in a number of cellular processes for selective degradation of proteins and involves three steps: (1) ATP dependent activation of ubiquitin by E1 enzyme, (2) transfer of activated ubiquitin to E2 and (3) transfer of ubiquitin to the protein to be degraded by E3 complex. F-box proteins are subunit of SCF complex and involved in specificity for a target substrate to be degraded. F-box proteins regulate many important biological processes such as embryogenesis, floral development, plant growth and development, biotic and abiotic stress, hormonal responses and senescence. However, little is known about the F-box genes in wheat. The draft genome sequence of wheat (IWGSC Reference Sequence v1.0 assembly) used to analysis a genome-wide survey of the F-box gene family in wheat. The Hidden Markov Model (HMM) profiles of F-box (PF00646), F-box-like (PF12937), F-box-like 2 (PF13013), FBA (PF04300), FBA_1 (PF07734), FBA_2 (PF07735), FBA_3 (PF08268) and FBD (PF08387) domains were downloaded from Pfam database were searched against IWGSC Reference Sequence v1.0 assembly. RNA-seq paired-end libraries from different stages of wheat, such as stages of seedling, tillering, booting, day after flowering (DAF) 1, DAF 10, DAF 20, and DAF 30 were conducted and sequenced by Illumina HiSeq2000 for expression analysis of F-box protein genes. Basic analysis including Hisat, HTseq, DEseq, gene ontology analysis and KEGG mapping were conducted for differentially expressed gene analysis and their annotation mappings of DEGs from various stages. About 950 F-box domain proteins identified by Pfam were mapped to wheat reference genome sequence by blastX (e-value < 0.05). Among them, more than 140 putative F-box protein genes were selected by fold changes cut-offs of > 2, significance p-value < 0.01, and FDR<0.01. Expression profiling of selected F-box protein genes were shown by heatmap analysis, and average linkage and squared Euclidean distance of putative 144 F-box protein genes by expression patterns were calculated for clustering analysis. This work may provide valuable and basic information for further investigation of protein degradation mechanism by ubiquitin proteasome system using F-box proteins during wheat development stages.

• Journal of the Korean GEO-environmental Society
• /
• v.17 no.7
• /
• pp.15-25
• /
• 2016

In the present work, a number of advanced three-dimensional (3D) parametric finite element numerical analyses have been conducted to study the behaviour of single piles and pile groups in consolidating ground from coupled consolidation analyses. Single piles, $4{\times}4$ and $6{\times}6$ piles inside groups with a spacing of 2.5D were considered, where D is the pile diameter. It has been found that dragload and downdrag on the piles developed rather quickly at the early stage of consolidation. However, when the degree of consolidation was more than 50~75%, only little increases of dragload and downdrag were induced on the pile. Negative Skin Friction (NSF) on the pile in the fill layer was mobilised quickly and remained constant throughout further consolidation. The development of NSF is influenced both by the relative shear displacements at the pile-soil interface and the vertical effective soil stresses during consolidation. The former governed the early stage of consolidation and the latter affected the later stage of consolidation. The vertical effective soil stresses adjacent to the piles were reduced due to the shear stress transfer at the pile-soil interface, in particular for piles inside the pile groups. The range of NSF influence zone concerning the reductions of the effective vertical soil stresses was about 20D measured from the piles in the horizontal direction. On the contrary, the effective horizontal soil stresses acting on the piles were similar to those at the far field.

• Korean Journal of Adult Nursing
• /
• v.12 no.2
• /
• pp.296-310
• /
• 2000

During the past 10 years, concern for community people's health has increased together with the changes. Public health policies and studies for community people's health, however, have influenced those in childmaternal health care to want more general coverage and studies of health and wellness. Particularly, the study of community people's health in the extent an island area is almost rare as that personal and the material benefits in this area are lacking of community people's work is large, and the basic elements of living, such as diet and elimination, are irregular due to the schedule of the tide. Thus, there are many potential health problems. In this regard, the study attempted to understand the health problems of island community people and to provide a basis for developing health promotion and health education programs. In collecting data for the study, face to face interviews were made through a structured questionnaire from October 1 to December 30, 1996. Collected data were analyzed with the SAS statistics program, descriptive statistics, t-test and ANOVA. Subjects' health status was examined by classifying into such categories as their health perception, complaints of health problem, related lifestyle, psychosocial health staus, the result of examination is as follows; 1. For subjects' health perception, 26.9% of the subject answered not sick, but not so healthy'; 30.9% thought they were healthy, while 22.9% answered that they were not healthy. 2. For the health problem complaints many complained of pains in their muscles and skeletal system, especially knee joint pain. Women's health problems related with breast and the reproductive system included 52.3% of cases doing breast self examination, while 56.55% received the cervical cancer screening test. In men's health problems, 44.2% of subjects answered that they have moderate to severe BPH(Benign Prostatic Hypertrophy) symptom. 3. There were statistically a significant difference in the degree of physical health according to marital status(p=0.0028), occupation(p=0.0442), income(p=0.0357). 4. For stress status, 17.2% was to need the intervention, 50.2% was to need observation. 5. The mean score of self-esteem was 27.7 showing a relatively high score. 6. For the rate of smoking, 37.7% used to smoke, while 28% used to take alcohol. 7. The rate of substance abuse was 45.9% of subjects. 8. Most of subjects' health behaviors included most of the acupuncture (52%). 9. The rate of subjects receiving comprehensive medical testing was 34.36% while 34.78% did after care managing behavior. 10. For the obesity grade, 53% is normal weight, low-weight 32.8%, obesity 33%. 11. For nutrition status, 78.7% illy balanced to need intervention of nutritional education. 12. For 78.7% of subjects, muscle strength and 40.7% of stretching were not good enough to need health education on physical exercises. Therefore, based on the results, appropriate health education programs need to be developed to promote health of community people on an island.

• Composites Research
• /
• v.29 no.3
• /
• pp.111-116
• /
• 2016

The tilting pad journal bearing for the turbo compressor application has a role to support high speed and heavy loading rotor. White metal has been widely used for the bearing material but the conventional bearing is immediately suspended and induces serious serious damage to the rotor under the unexpected oil cut situation or the insufficient oil film formation. The carbon fiber reinforced composite having high specific stiffness, specific strength and excellent tribological characteristics can solve these seizure problems. In this work, the study on the durability of high thermal resistance carbon fiber/epoxy composite tilting pad journal bearing under oil cut situation was conducted. The material properties of the composite materials including tensile, compressive and interlaminar properties were measured at room and high temperature of oil cut situation. To investigate the possibility of failure of composite tilting pad journal bearing under oil cut situation, the stress distribution of the composite bearing was analyzed via finite element analysis and the Tsai-Wu Failure index was calculated. To verify the failure analysis results, the oil cut tests for the composite tilting pad journal bearing were conducted using industrial test bench.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.35 no.8
• /
• pp.889-897
• /
• 2011

In this work, we investigated the theoretical forming limit models for Zircaloy-4 and Zirlo used for spacer grid of nuclear fuel rods. Tensile and anisotropy tests were performed to obtain stress-strain curves and anisotropic coefficients. The experimental forming limit diagrams (FLD) for two materials were obtained by dome stretching tests following NUMISHEET 96. Theoretical FLD depends on FL models and yield criteria. To obtain the right hand side (RHS) of FLD, we applied the FL models (Swift's diffuse necking, M-K theory, S-R vertex theory) to Zircaloy-4 and Zirlo sheets. Hill's local necking theory was adopted for the left hand side (LHS) of FLD. To consider the anisotropy of sheets, the yield criteria of Hill and Hosford were applied. Comparing the predicted curves with the experimental data, we found that the RHS of FLD for Zircaloy-4 can be described by the Swift model (with the Hill's criterion), while the LHS of the FLD can be explained by Hill model. The FLD for Zirlo can be explained by the S-R model and the Hosford's criterion (a = 8).

• Asian Pacific Journal of Cancer Prevention
• /
• v.17 no.7
• /
• pp.3483-3487
• /
• 2016

Background: Cigarette smoking is one of the leading causes of death in the world. Tobacco consumption has grave negative consequences for health so that it is important to understand the reasons and motivations towards cigarette smoking and barriers against quitting smoking among the young generation for developing effective policies to control this widespread problem. Materials and Methods: This cross-sectional survey was carried out at the Faculty of Medicine, Rabigh, King Abdulaziz University, Jeddah, Saudi Arabia. A total of 438 young smokers participated from the University and the general population. Data were collected through anonymous, self-administered questionnaires in the Arabic language that contained questions about the reasons and motivations towards cigarette smoking and barriers against quitting smoking. The questionnaire also contained several questions regarding knowledge and attitude of the participants towards cigarette smoking. The data was analyzed on SPSS-16. Results: The mean age of the respondents was $22.9{\pm}3.48$, out of 438 subjects 87 (19.9%) were married, and 351 (80.1%) were unmarried, and 331 (75.6%) belonged to urban areas while 107 (24.5%) were from the rural areas. Responding to a question about a number of cigarettes smoked per day, 31% answered 11-20, 29% answered 21-30, and 25% answered 1-10. Questioned about smokers in the family, 34.5% responded more than one, with 19% for brother and 13% for father. About the reasons for not quitting smoking, 26% described lack of willpower, 25% had no reason, 22% said that people around me smoke, and 15.3% responded stress at home/work. The major motivation for smokers was smoker friends (42%), for 33.8% others, for 12% father/brother and 7.8% media. Conclusions: There are several avoidable and preventable reasons and barriers against quitting smoking. However, knowledge and attitude about smoking were good, and the majority of the smokers were well aware of the associated hazards. Therefore, there is a need to search out ways and means to help them to quit this addiction.

• Asian-Australasian Journal of Animal Sciences
• /
• v.14 no.11
• /
• pp.1610-1615
• /
• 2001

Three studies were conducted to determine the effect of sex on pre- and post-weaning performance of pigs. These studies were conducted in response to observations that female pigs appear to grow faster than male pigs after weaning. In addition, female pigs have been found to grow faster than male pigs when supplied with supplemental milk before weaning. The aims of the present work were to further characterise the ontogeny of sex differences growth of nursing and growing pigs. In the first study, piglets sucking 32 sows were crossfostered to produce litters of 10 boars (n=9), 10 gilts (n=l 1) or 5 boars and 5 gilts (n=12). Liveweight of the sucking pigs was then measured weekly until weaning at 4 weeks of age. In the second study, 80 boars and 80 gilts were weaned at 26 days of age and growth performance measured until 21 days post-weaning. In the third experiment, 40 boars and 40 gilts were weaned into groups of 5 pigs at either 17 or 25 days of age and pigs were weighed until they were approximately 90 kg liveweight. All-boar litters grew more slowly than the all-gilt and mixed litters such that by 14 days of age the all-boar litters were 10% lighter than the all-gilt or mixed litters (39 vs. 43.8 kg, p=0.050). The proportional difference in litter weight appeared to be maintained at 21 days of age (53.9 vs. 59.4 kg, p=0.063) but was diminished by 28 days of age (66.5 vs. 70.8 kg, p=0.28). In the second study, gilts grew more quickly than boars over the first 7 and 21 days post-weaning and as a consequence were 10% heavier than boars at 21 days after weaning (13.7 vs 12.48 kg, p=0.001). In the third study, gilts grew more quickly than boars in the immediate 7 days post-weaning (40 vs. 5 g/day, p=0.014) whereas from 7 until 35 days post-weaning there was no significant difference in growth rate (381 vs. 360 g/day, p=0.19). Gilts also grew more quickly than boars over the 14 days after being moved into the grower (631 vs. 570 g/day, p=0.013) and finisher (749 vs. 688 g/day, p=0.038) sheds. However, these differences were not maintained over the entire period in each shed. These data support the hypotheses that gilts handle the stresses of weaning and other transitions better than boars.