• Korean Journal of Materials Research
• /
• v.22 no.11
• /
• pp.615-619
• /
• 2012

Recently, ultrafine grained (ufg, typically 100 > d > 500 nm) Ti-Fe eutectic materials have been highlighted due to their extraordinarily high strength and good abrasion resistance compared to conventional coarse grained (cg, d > $1{\mu}m$) materials. However, these materials exhibit limited plastic strain and toughness during room temperature deformation due to highly localized shear strain. Several approaches have been extensively studied to overcome such drawbacks, such as the addition of minor elements (Sn, Nb, Co, etc.). In this paper, we have investigated the influence of the addition of Gd and Y contents (0.3-1.0 at.%) into the binary Ti-Fe eutectic alloy. Gd and Y are chosen due to their immiscibility with Ti. Microstructural investigation reveals that the Gd phase forms in the eutectic matrix and the Gd phase size increases with increasing Gd content. The improvement of the mechanical properties is possibly correlated to the precipitation hardening. On the other hand, in the case of Ti-Fe-Y alloys, with increasing Y contents, primary phases form and lamellar spacing increases compared to the case of the eutectic alloy. Investigation of the mechanical properties reveals that the plasticity of the Ti-Fe-Y alloys is gradually improved, without a reduction of strength. These results suggest that the enhancement of the mechanical properties is closely related to the formation of the primary phase.

• Steel and Composite Structures
• /
• v.25 no.1
• /
• pp.117-126
• /
• 2017

The component method is an analytical approach for investigating the moment-rotation relationship of steel connections. In this study, the component method was improved from two aspects: (i) load analysis of mechanical model; and (ii) combination of spring elements. An optimized component method with more reasonable component models, spring arrangement position, and boundary conditions was developed using finite element analysis. An experimental testing program in two major-axis and two minor-axis connections under symmetrically loading was carried out to verify this method. The initial rotational stiffness obtained from the optimized component method was consistent with the experimental results. It can be concluded that (i) The coupling stiffness between column and beam flanges significantly affects the effective height of the tensile-column web. (ii) The mechanical properties of the bending components were obtained using an equivalent t-stub model considering the bending capacity of bolts. (iii) Using the optimized mechanical components, the initial rotational stiffness was accurately calculated using the spring system. (iv) The characteristics of moment-rotation relationship for beam to column connections were effectively expressed by the SPRING element analysis model using ABAQUS. The calculations are simpler, and the results are accurate.

• Microbiology and Biotechnology Letters
• /
• v.49 no.4
• /
• pp.510-518
• /
• 2021

Bacteriophages are considered excellent sensing elements for platforms detecting bacteria. However, their lytic cycle has restricted their efficacy. Here, we used the minor coat protein pIII domain (N1N2) of phage CTXφ to construct a novel surface plasmon resonance (SPR) biosensor that could detect Vibrio cholerae. N1N2 harboring the domains required for phage adsorption and entry was obtained from Escherichia coli using recombinant protein expression and purification. SDS-PAGE revealed an approximate size of 30 kDa for N1N2. Dot blot and transmission electron microscopy analyses revealed that the protein bound to the host V. cholerae but not to non-host E. coli K-12 cells. Next, we used amine-coupling to develop a novel recombinant N1N2 (rN1N2)-functionalized SPR biosensor by immobilizing rN1N2 proteins on gold substrates and using SPR to monitor the binding kinetics of the proteins with target bacteria. We observed rapid detection of V. cholerae in the range of approximately 10³ to 10⁹ CFU/ml but not of E. coli at any tested concentration, thereby confirming that the biosensor exhibited differential recognition and binding. The results indicate that the novel biosensor can rapidly monitor a target pathogenic microorganism in the environment and is very useful for monitoring food safety and facilitating early disease prevention.

• Korean Journal of Social Welfare
• /
• v.68 no.2
• /
• pp.131-160
• /
• 2016

In this study, we analyzed determination of punishment of victimizers presented in sentencing(81 plaintiffs, 95 sentencing) for 55 cases involving child maltreatment fatalities between 2001 and 2015. The results showed that about 40% of main victimizers were imposed relatively minor punishment such as probation or imprisonment for less than 3 years. Judgments that deviated from lower limit comprised large proportion in connection with compliance with standards for statutory punishment and punishment determination. The elements of punishment determination, such as earnest rearing of child, psychological pain arising from death of child, sense of guilt, motivation that can be considered, were found to have a significant influence on mitigation of punishment although such elements could be judged differently, depending on perception or subjective tendency of judges towards child abuse. Even abetters in a position to prevent death of child were imposed minor punishment mostly by probation or monetary penalty. This study presented the need to reconsider the circumstances of punishment determination which has been conventionally mentioned in cases involving child maltreatment fatalities, such as first offender, accidental crime, person with parental rights, fosters, agreement with family of the deceased, etc. Moreover, this study suggested the need to reinforce child abuse prevention training for law enforcement officers and to revamp standards for determining punishment unique to the cases of child abuse in the future.

• Korean Journal of Heritage: History & Science
• /
• v.51 no.4
• /
• pp.224-233
• /
• 2018

Thirty-three Early Iron Age bronzes at the sites of Hoam-dong in Chungju and Cheongsong-ri in Buyeo were investigated in order to study the manufacturing technique and the provenance of lead. Chemical analysis using X-ray fluorescence showed that 33 bronzes consist of copper(Cu), tin(Sn) and lead(Pb) served as major elements. Major and minor elemental analyses by EPMA were performed on two mirrors and 2 weapons of the bronzes investigated. The results shows that bronze mirrors from Chungju and Buyeo were high-tin bronzes(> 30 wt%). And 20% of tin and 5% of lead were founded in bronze weapons. Iron, zinc, arsenic, silver, nickel, sulfur and cobalt detected in four bronzes as minor and trace elements. The four bronzes were alloyed considering their function and were not heat treated after casting due to their high tin content. Lead isotope analysis using TIMS indicates that thirty-three bronzes were distributed southern Korea peninsula except Zone 1. As a result, lead raw materials came from various regions in Korean Peninsula not from Gyeongsang-do regions. The manufacturing techniques of bronze ware generalized at this age, and bronze was produced in various sites using raw materials from various sources.

• Journal of Korea Entertainment Industry Association
• /
• v.13 no.6
• /
• pp.25-32
• /
• 2019

According to a recent KOFICE survey, K-Pop's popularity factor is divided into visual and auditory elements, and the importance of hearing elements is found. Among the various types of singers, idol groups led K-Pop and Black Pink, which topped the list of favorite K-Pop singers in 2018, was selected as the study target. In addition, Twice's music, which is similar to Black Pink's period of activity, has been set as a comparative research scope. The common features in the music of the two groups are the chorus and rhythm structure implemented around melody and Harmony rhythm, and the frequency of use of Major and Minor is greatly different. Through this method and modal interchange, K-Pop from 2016 to 2018 is analyzed. Research shows that first, more than one mode is used as a main melody. When more than one mode is used, different lines in the same line will vary depending on the functional form of the song. Second, the rhythm of the melody expressed with vocals and instruments is repeated based on a two-bar pattern. Finally, when using less chord and slowly expressing the igneous rhythms, there is a way to omit or modify the third notes that determine chord characteristics. Through this study, we can see that the usage patterns of the mode and modal interchange are divided according to the major and minor.

• The Korean Journal of Quaternary Research
• /
• v.7 no.1
• /
• pp.69-91
• /
• 1993

A total of 76 surface sediment samples, collected from the Korean west coast and the eastern Yellow Sea areas, were analyzed for their elemental composition in order to understand the geochemical characteristics of these deposits. The analyzed elements included 9 major elements (Al, Fe, Na, K, Mg, Ca, Ti, P, Mn), 8 minor elements (Sr, Ba, V, Cr, Co, Ni, Cu, Zn), organic carbon and calcium carbonate. Contents of most analyzed elements, excluding K and Ba, were generally low compared to those of average crust. Contents of most elements, except K and Ca, also correlated with sediment grain size, though the degree of relationship varied widely from one element to another. For fine-grained sediments, a distinction could be made between those in the central Yellow Sea and those in the Keum Estuary based on their characteristic elemental composition: the former were rich in Fe, Na, K, Mg, Ca and V, and the latter in Mn, Co and Ni. The element/aluminium ratios, on the other hand, showed that the central Yellow Sea muds were enriched in Fe, Mg, V, Ni, Cu and Zn and depleted in K, Mn, Ba and Sr relative to the mud located near the Korean Peninsula. Based on the analysis of these results, as well as of the influences of particular mineral phases or pollution effects, we could suggest geochemical criteria which can be used in distinguishing muds from the two different sources, the Keum River and the Yellow River: the former by the higher Mn content and the latter by the higher Mg and V contents, relative to each other.

• Analytical Science and Technology
• /
• v.22 no.3
• /
• pp.235-246
• /
• 2009

The analyses of minor and trace elements in glass debris were performed using LA-ICP-MS in order to identify manufacturers using real commercial samples. At first, a calibration curve was made using standard glass samples of NIST 610, 612, 614 and 616. $^{29}Si$ was used as an internal standard, and the ratios of metal/Si for each metal were compared with their concentrations. Based on elements in each sample and standard materials, 24 metals were quantified and the LOD in analysis, according to the blank sample, was in the range of 0.11 mg/kg (Ti)-4.91 mg/kg (Ca). Eleven samples from two manufacturers were collected and five sub-samples were taken from each sample for analysis. 15 elements (Co, Ce, Ca, Mn, Sr, Ba, Li, Rb, U, La, Th, Na, Al, Zr and Hf) were selected to identify manufacturers because some elements (Cu, Cr, Cd and Ni) were below the detection limit and some elements (Ti, Pr, Mg, Nb, Nd) were absent in the analysis of standards and others (Pb and Sn) had a problem of homogeneity. The attempts to identify manufacturers and the manufacturing period were performed through a triangular diagram. In the manufacturer discrimination by discriminant analysis, a canonical discriminant function was made based on Mn, Ce and Rb, and each sample could be identified.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.33 no.s01
• /
• pp.86-97
• /
• 1988

Sesame(Sesamum indicum L.) is probably the most ancient oilseed crop known in the world. The seed of sesame is used in a variety of ways as food. The whole seed may be eaten raw, either roasted or parched, or fed to birds and stock. Sesame oil is used as a salad or cooking oil, in shortening, margarine and in the manufacture of soap. Minor uses are as a fixative in the perfume industry and formerly as a carrier for fatsoluble substances in pharmaceuticals such as penicillin. One of the minor constituents of sesame oil, sesamin, is used for its synergistic effect in pyrethrin insecticides, in addition of a small quantity of this substance markedly increases the effectiveness of fly sprays. The meal remaining after oil extraction can be used as and animal feed-stuff or as manure. In general sesame meal is considered to be equal to cottonseed or soybean meal as a protein supplement for livestock and poultry. It is especially high in certain amino-acids such as methionine, which is low in soybean meal, and thus can be combined with it or similar meal to form a more balanced ration. An attempt to summarize the literature review on quality improvement of sesame was made to discuss the accomplishments of the past and perspectives in the future. The reviews on quality improvement of sesame were mainly discussed in connection with the cultural practices and genetic informations in current status. The emphasis focussed on environmental variation of quality in cultural practices, such as harvest time, variety by location, climatic condition, fertilizer application, and growth regulator treatment. On the genetic variation of quality, it was discussed on variety background, mutation breeding, correlations, and inheritance of quality related characteristics. It also was discussed on relationship between quality and plant traits, storage condition or period, and seed coat color. Moreover, current research status were reviewed on some minor elements such as sesamin, oxalic acid, and trypsin inhibitor. As a results of the review, the lack of an effort to quality improvement in each utilization area was indicated as a problem area. More active efforts for the improvement of quality were also insufficient to incorporate the available genes for quality in breeding method or collection and analysis of breeding materials. Therefore, researches in the future would be recommended to emphasize on these problem areas.

• The Journal of the Acoustical Society of Korea
• /
• v.42 no.1
• /
• pp.75-82
• /
• 2023

The purpose of this study was to investigate listener's affective responses to different vocal registers and modes in terms of valence (i.e., negative to positive affect) and arousal (i.e., low to high energy level). The data were collected from four different conditions (i.e., higher and lower registers paired with major and minor modes). A total of 188 female college students participated in the survey online and rated their perceived valence and arousal levels on a visual analogue scale after listening to each excerpt. The two-way analysis of variance (ANOVA) was administered for data analysis. The results revealed that there were significant differences in the affective responses to the two vocal registers, showing that the arousal was more affected by the register than the valence. Secondly, mode had statistically significant impact on both valence and arousal while weighing more on valence. Further, there was significant interaction effect of vocal register and mode on valence, but not on arousal. Results also displayed that listeners had the most negative valence when listening to the excerpt of minor mode in higher register, while having the lowest arousal when listening to the excerpt of minor mode in lower register. These findings imply that it is important to consider the vocal range as well as the musical mode when selecting music for appreciation.