• Structural Engineering and Mechanics
• /
• v.25 no.1
• /
• pp.53-73
• /
• 2007

In this study, an effective load increment method for multi modal adaptive non-linear static (pushover) analysis (NSA) for building type structures is presented. In the method, lumped plastisicity approach is adopted and geometrical non-linearties (second-order effects) are included. Non-linear yield conditions of column elements and geometrical non-linearity effects between successive plastic sections are linearized. Thus, load increment needed for formation of plastic sections can be determined directly (without applying iteration or step-by-step techniques) by using linearized yield conditions. After formation of each plastic section, the higher mode effects are considered by utilizing the essentials of traditional response spectrum analysis at linearized regions between plastic sections. Changing dynamic properties due to plastification in the system are used on the calculation of modal lateral loads. Thus, the effects of stiffness changes and local mechanism at the system on lateral load distribution are included. By using the proposed method, solution can be obtained effectively for multi-mode whereby the properties change due to plastifications in the system. In the study, a new procedure for determination of modal lateral loads is also proposed. In order to evaluate the proposed method, a 20 story RC frame building is analyzed and compared with Non-linear Dynamic Analysis (NDA) results and FEMA 356 Non-linear Static Analysis (NSA) procedures using fixed loads distributions (first mode, SRSS and uniform distribution) in terms of different parameters. Second-order effects on response quantities and periods are also investigated. When the NDA results are taken as reference, it is seen that proposed method yield generally better results than all FEMA 356 procedures for all investigated response quantities.

• Journal of The Geomorphological Association of Korea
• /
• v.18 no.4
• /
• pp.261-270
• /
• 2011

This study is to describe morphological linear anomalies manifested in the geomorphological landscapes of Woongcheon river-basin, situated in the western ends of Charyong Mountainous Range, and to elucidate their morphotectonic significance. The order of decreasing valley scale in the study area is NE-SW, NNE-SSW, NNW-SSE, N-S, and E-W series. The valleys of NE-SW lineament appear as the largest in the study area, having piedmont slope, terraces, low-relif hills. NNE-SSW lineament cross obliquely the geomorphological elements of the precedent lineament. NNW-SSE, N-S and E-W lineament cut the forms of higher orders showing NE-SW and NNE-SSW lineament. Scale of the linear valleys is not correlated with the order of streams. It is paradoxal that great valleys are not associated with the rivers of highest order. It owes to adaption of regional discharge system along the valleys exploiting the fracture resulted from succeeding tectonic accidents.

• Journal of the Mineralogical Society of Korea
• /
• v.32 no.4
• /
• pp.235-247
• /
• 2019

The Central South Sea Mud (CSSM), developed in the Seomjin River estuary, is known to be supplied with sediments from Heuksan Mud Belt (HMB) and Seomjin River. However, in order to form a mud belt, more sediments must be supplied than supplied in the above areas. Therefore, research on additional sources should be conducted. In this study, clay minerals, major elements analyzes were performed on cores 16PCT-GC01 and 16PCT-GC03 in order to investigate the transition in the provenance and transport pathway of sediments in CSSM. The Huanghe sediments are characterized by higher smectite and the Changjiang sediments are characterized by higher illite. Korean river sediments contain more kaolinite and chlorite than those of chinese rivers. Korean river sediments have higher Al, Fe, K concentraion than Chinese river sediments and Chinese rivers have higher Ca, Mg, Na than those of Korean rivers. Therefore, clay minerals and major elements can be a useful indicator for provenance. Based on our results, CSSM can be divided into three sediment units. Unit 3, which corresponds to the lowstand stage, is interpreted that sediments from Huanghe were supplied to the study area by coastal or tidal currents. Unit 2, which corresponds to the transgressive stage, is interpreted to have a weaker Huanghe effect and a stronger Changjiang and Korean rivers effect. Unit 1, which corresponds to the highstand stage when the sea level is the same as present and current circulation system is formed, is interpreted that sediments from Changjiang and Korean rivers are supplied to the research area through the current.

• Science of Emotion and Sensibility
• /
• v.13 no.4
• /
• pp.621-634
• /
• 2010

This study aimed to investigate the effects of dimensions of movie clip (2D vs. 3D), viewing orders (2D ${\to}$ 3D vs. 3D ${\to}$ 2D), and gender difference on participants' subjective fatigue, recognition for the elements in the clips, and arousal level. The results can be summarized as followings. First, subjective fatigue level was higher in the 3D condition than 2D condition, but this tendency was more clear in the 2D ${\to}$ 3D condition than in the 3D ${\to}$ 2D condition. Second, correct recognition rates were significantly higher for 3D than 2D only in the 3D ${\to}$ 2D condition. In particular, male participants showed higher correct recognition rates than female participants in the 3D clip condition, whereas female participants showed higher correct recognition rates than male participants in the 2D clip condition. Third, although 3D clips tended to induce higher level of arousal, this tendency was showed only in the 2D ${\to}$ 3D condition, which implied previous exposure to 2D clip increased the arousal level in following 3D clip than vice versa.

• The Journal of the Acoustical Society of Korea
• /
• v.33 no.3
• /
• pp.191-199
• /
• 2014

Wave reflection and transmission characteristics in waveguides are an important issue in many engineering applications. A combined spectral element and finite element (SE/FE) method is used to investigate the effects of local non-uniformities but limited at relatively low frequencies because the SE is formulated by using a beam theory. For higher frequency applications, a method named a combined spectral super element and finite element (SSE/FE) method was presented recently, replacing spectral elements with spectral super elements. This SSE/FE approach requires a long computing time due to the coupling of SSE and FE matrices. If a local non-uniformity has a uniform cross-section along its short length, the FE part could be further replaced by SSE, which improves performance of the combined SSE/FE method in terms of the modeling effort and computing time. In this paper SSEs are combined to investigate the characteristics of waves propagating along waveguides possessing geometric non-uniformities. Two models are regarded: a rail with a local defect and a periodically ribbed plate. In the case of the rail example, firstly, the results predicted by a combined SSE/FE method are compared with those from the combined SSEs in order to justify that the combined SSEs work properly. Then the SSEs are applied to a ribbed plate which has periodically repeated non-uniformities along its length. For the ribbed plate, the propagation characteristics are investigated in terms of the propagation constant.

• Korean Journal of Childcare and Education
• /
• v.8 no.5
• /
• pp.25-45
• /
• 2012

The aim of the present study was to analyze the elements of young children's leadership which is influenced by socio-demographic variable elements, mother's parental attitude and the ability of children' self-regulation with subjects of 435 five-year-old children and their mothers. Results showed that there was a difference in children's total leadership according to the gender. Regarding differences of mother's rearing attitude, boys showed higher self-control and leadership than girls. In differences of self-regulation and leadership, girls had a higher ability of self-regulation and leadership than boys. For birth order, parents who had more than 2 children show higher Control enemy rearing attitude. Regarding mother's employment, a working mother had freer rearing attitudes. Regarding a mother's educational background, there were differences of groups among rearing attitudes. In differences of family monthly income, there were differences regarding AE static rearing attitudes, autonomous parenting attitudes and get-up-and-go of leadership. Secondly, as a result of the relationship among mother's rearing attitudes had a static correlation between autonomous parenting attitudes and control enemy rearing attitudes. Thirdly, the children's leadership is high when the family income is high, mother's rearing attitude is free and children's ability of self-control is high.

• Journal of the Korean Society of Clothing and Textiles
• /
• v.32 no.10
• /
• pp.1509-1521
• /
• 2008

The subjects of this study were middle-aged women in their 40s$\sim$50s and older women aged 60 and over who were living in Seoul and Kyonggi-do, Korea. Through studying the participants' responses to the questions regarding the attributes of apparel quality in terms of the levels of satisfaction and importance, the target consumers' demand has been studied. And, they are applied to a QFD Matrix, to find out the relationship between the attributes of product quality and the guidelines of clothing design. For this study, apparel product quality is composed of five parameters: practicality, aesthetics, brand image, ease of care and fit. For the parameters of apparel product quality, the result of this study show that product improvements are needed in fit, aesthetics and practicality(in order of importance). The level of satisfaction(how satisfied consumer feels) was marked higher in brand image than that of importance(how important it is). To review demands for the apparel product attributes of formal suits for middle-aged and older women, the priority of these attributes through QFD Matrix that shows the relationship between the attributes and dress elements emphasized by designers has been examined. Material was the most important design element in designing formal suits. The shape of the pants was the second because the harmony between the jacket and the pants is important in formal suits. These were followed by trim and color tone of the jacket.

• Asian Pacific Journal of Cancer Prevention
• /
• v.17 no.10
• /
• pp.4761-4767
• /
• 2016

Objective: The use of Shamma (smokeless tobacco) by certain groups is giving rise to health problems, including cancer, in parts of Saudi Arabia. Our objective was to determine metals levels in Shamma using inductively coupled plasma mass spectrometry (ICP-MS). Methods: Thirty-three samples of Shamma (smokeless tobacco) were collected, comprising four types: brown Shamma (n = 14.0), red Shamma (n = 9.0), white Shamma (n = 4.0), and yellow Shamma (n = 6.0). All samples were collected randomly from Shamma users in the city of Najran. Levels of 11 elements (Al, As, Cd, Co, Cr, Cu, Li, Mn, Ni, Pb, and Zn) were determined by ICP-MS. Results: A mixed standard (20 ppb) of all elements was used for quality control, and average recoveries ranged from 74.7% to 112.2%. The highest average concentrations were found in the following order: Al ($598.8-812.2{\mu}g/g$), Mn ($51.0-80.6{\mu}g/g$), and Ni ($23.2-53.3{\mu}g/g$) in all four Shamma types. The lowest concentrations were for As ($0.7-1.0{\mu}g/g$) and Cd ($0.0-0.06{\mu}g/g$). Conclusions: The colour of each Shamma type reflects additives mixed into the tobacco. Cr and Cu were showed significant differences (P < 0.05) among Shamma types. Moreover, Pb levels are higher in red and yellow Shamma, which could be due to use (PbCrO4) as yellow colouring agent and lead tetroxide, Pb3O4 as a red colouring agent. The findings from this study can be used to raise public awareness about the safety and health effects of Shamma, which is clearly a source of oral exposure to metals.

• Journal of Korean Society of Rural Planning
• /
• v.16 no.3
• /
• pp.143-157
• /
• 2010

This study provides a physical indicator of landscape that can be guidelines so as to evaluate landscape agricultural region for visual landscape planning, finds out the guideline for visual landscape planning lastly through examining importance of indicators and the preference of each indicator of landscape. The physical landscape indicators were derived from document study and questionnaire survey to evaluate visual landscape on landscape agricultural region. In addition, field study was conducted to examine and inspect the physical landscape indicator, managers' interview and photograph was took for evaluating the landscape simulation. Moreover, the important elements for visual landscape planning of landscape agricultural region, the importance of physical landscape indicator and the preferences of each indicator were derived by conducting questionnaire to experts and general publics. The physical landscape indicator guideline was established from the following procedures. In case of the land, flat area had higher preference than steep region. So, planning an agricultural area at a flat region with open space will be better than establishing an agricultural area on a steep region. In case of the kind of landscape crops, For the background of landscape agricultural region, the seashore type had the highest preference and mountain type and non-background type was followed in order. According to the study, facilities built with natural elements such as straw-roofed pavilion received high preference. Therefore, look-out shed and straw-roofed pavilion should be introduced in the landscape agriculture planning to select materials and colors to keep harmony with the nature. The result of this study could be used as a best choice for improving visual landscape of landscape agricultural region on selecting suitable land, facilities and so on. Moreover, the results of manager interview could be used as a useful tool in the management and formation of visual landscape. The landscape point evaluating visual landscape of landscape agricultural region could be used as a reference for establishing relative guideline for the direct payment program for rural landscape conservation and landscape agreement. In addition, it could be a useful reference to improve the general landscape and revitalize the rural area.

• Journal of Surface Science and Engineering
• /
• v.46 no.5
• /
• pp.216-222
• /
• 2013

In order to improve the performance of electrodeposited diamond-nickel composite, surface modification of diamond particles was carried out using powder immersion reaction assisted coating (PIRAC). Titanium and chromium were selected as coating elements, which are known as carbide former. With respect to the powder elements, various phases were formed on diamond; metallic Ti and TiC for Ti powder, $Cr_3C_2$ for Cr powder, and TiC and $Cr_3C_2$ for Ti-Cr mixed powder. Surface modified diamond particle showed higher specific surface area, especially Ti coating induced considerable increase of specific surface area. The increase of specific surface area suggests increase of surface roughness, and that was confirmed by surface observation using FE-SEM. In addition, wear properties of diamond-nickel composite including surface modified diamonds were improved, and Ti coated diamond showed the highest performance. The wear property of diamond-nickel composite is dependent on adhesion strength between diamond particle and nickel layer. Therefore, surface modification of diamond particle by PIRAC increasing surface roughness is effective to improve the properties of diamond-nickel composite.