• Journal of Korean Society on Water Environment
• /
• v.33 no.6
• /
• pp.640-649
• /
• 2017

The purpose of this study is the analysis of the water quality spatial characteristics for the main stream of Nakdong River in consideration of the tributary inflow. The flow and water quality (BOD, TOC, TP) data for 32 monitoring stations located in the main stream and the tributaries of Nakdong River were collected from 2003 to 2016. From the results of the flow and water quality analyses for each site, a status map of the flow and the water quality for Nakdong River was produced. The water quality of each river section was classified according to seven river-environment standards. The water quality changes in the main stream before and after the confluence were analyzed spatially. As a result, the water quality of Kumho River, in particular the Kumho B to Kumho C section, is the worst among the tributaries. In addition, the water quality grades of the lower streams such as Nam River and Miryang are worse than that of the upper streams of the Nakdong River. In the case of the main stream, the water quality grades of the sections between the Wicheon and Nam River confluences and the section from Nakbon L to Nakbon N are relatively poor.

• Bulletin of the Korean Chemical Society
• /
• v.31 no.4
• /
• pp.989-998
• /
• 2010

The titled dye of DBPI gives amplified spontaneous emission (ASE) with maximum at 580 nm upon pumping by nitrogen laser (${\lambda}_{ex}\;=\;337.1\;nm$). The ground state absorption cross section (${\sigma}_A$) and emission cross section (${\sigma}_E$) as well as effective emission cross section(${\sigma}^*_E$) have been determined. The electronic absorption spectra of DBPI were measured in ethanol and tetrahydrofuran at room and low temperature. DBPI displays molecular aggregation in water. The photochemical reactivity of DBPI was also studied in carbon tetrachloride upon irradiation with 525 nm light. The electrochemical investigation of DBPI dye has been carried out using cyclic voltammetry and convolution deconvolution voltammetry combined with digital simulation technique at a platinum electrode in 0.1 mol/L tetrabutyl ammonium perchlorate (TBAP) in two different solvents acetonitrile ($CH_3CN$) and dimethylformamide (DMF). The species were reduced via consumption of two sequential electrons to form radical anion and dianion (EE mechanism). In switching the potential to positive direction, the compound was oxidized by loss of two sequential electrons, which were followed by a fast dimerization and/or aggregation process i.e $EC_{dim1}EC_{dim2}$ mechanism. The electrode reaction pathway and the chemical and electrochemical parameters of the investigated compound were determined using cyclic and convolutive voltammetry. The extracted electrochemical parameters were verified and confirmed via digital simulation method.

• Computers and Concrete
• /
• v.30 no.2
• /
• pp.127-141
• /
• 2022

In this paper, a numerical procedure is proposed for achieving the minimum cost design of reinforced concrete polygonal column cross-sections under compression and biaxial bending. A methodology is developed to integrate the metaheuristic algorithm Quantum Particle Swarm Optimization (QPSO) with an algorithm for the evaluation of the strength of reinforced concrete cross-sections under combined axial load and biaxial bending, according to the design criteria of Brazilian Standard ABNT NBR 6118:2014. The objective function formulation takes into account the costs of concrete, reinforcement, and formwork. The cross-section dimensions, the number and diameter of rebar and the concrete strength are taken as discrete design variables. This methodology is applied to polygonal cross-sections, such as rectangular sections, rectangular hollow sections, and L-shaped cross-sections. To evaluate the efficiency of the methodology, the optimal solutions obtained were compared to results reported by other authors using conventional methods or alternative optimization techniques. An additional study investigates the effect on final costs for an alternative parametrization of rebar positioning on the cross-section. The proposed optimization method proved to be efficient in the search for optimal solutions, presenting consistent results that confirm the importance of using optimization techniques in the design of reinforced concrete structures.

• Steel and Composite Structures
• /
• v.44 no.6
• /
• pp.789-801
• /
• 2022

In order to study the influence of loading angles on seismic performance of steel reinforced concrete (SRC) special-shaped columns, cyclic loading tests and finite element analysis (FEA) were both carried out. Seven SRC special-shaped columns, including two L-shaped columns, three T-shaped columns and two cross-shaped columns, were tested, and the failure patterns of the columns with different loading angles were obtained. Based on the tests, the FEA models of SRC special-shaped columns with different loading angles were established. According to the simulation results, hysteretic curves and seismic performance indexes, including bearing capacity, ductility, stiffness and energy dissipation capacity, were analyzed in detail. The results showed that the failure patterns were different for the columns with the same section and different loading angles. With the increasing of loading angles, the hysteretic curves became fuller and the bearing capacity and initial stiffness appeared increasing tendency, but the energy dissipation capacity changed insignificantly. When the loading angle changed, the ductility got better with the larger area of steel at the failure side for the unsymmetrical section and near the neutral axis for the symmetrical section, respectively.

• Korean Journal of Agricultural Science
• /
• v.50 no.4
• /
• pp.645-652
• /
• 2023

The aleurone layer in maize is crucial as it contains essential nutrients such as minerals, vitamins, and high-quality proteins. While most of the maize varieties are known to possess a single aleurone layer, several multi-aleurone layer mutants and landraces have been suggested for hierarchical genetic control of aleurone development. Conventional microscopy analysis often involves using immature seeds or sampling only a portion of the kernel sample, and whole kernel section analysis using a microtome is technically difficult and time-consuming. Additionally, the larger size of maize kernels posed challenges for comprehensive cross-sectional analysis compared to other cereal crops. Consequently, this study aimed to develop an efficient method to comprehensively understand the aleurone layer characteristics of the entire cross-section in maize. Through observations of diverse maize genetic resources, we confirmed irregular aleurone layer patterns in those with multiple aleurone layers, and we discovered a landrace having multiple aleurone layers. By selectively identifying genetic resources with multiple aleurone layers, this method may contribute to efficient breeding processes in maize.

• Journal of the Korean Geotechnical Society
• /
• v.27 no.2
• /
• pp.91-101
• /
• 2011

In this study, a new design method of Pile-Bent structure considering plastic hinge was proposed on the basis of the beam-column model. To obtain the detailed informations, the optimized cross-section ratio between column and pile was analyzed to induce the plastic hinge at the joint section between the pile and column. Base on this study, the optimized diameter ratio of pile and column can be obtained below the inflection point of the bi-linear curve depending on the relations between column-pile diameter ratio ($D_c/D_p$) and normalized lateral cracking load ratio ($F/F_{Dc=Dp}$). Moreover, through comparisons with field cases to find out in-depth limit in which minimum concrete-steel ratio could be applied, in-depth limits ($L_{As=0.4%}$) normalized by the pile length ($L_p$) proportionally decrease as the pile length ($L_p/D_p$)increases up to $L_p/D_p=17.5$, and beyond that in-depth limit converges to a constant value (${\simeq}0.3$).

• Journal of Fashion Business
• /
• v.10 no.5
• /
• pp.135-158
• /
• 2006

The purpose of this study was to provide for the useful fundamental data by developing an appearl sizing system according to body types for Chinese Adult Female. Thus, it was to improve of fittness and coverage rate of exporting domestic clothing to China. For study, It was measured 1360 female women aged between 19 and 50 who resident in Beijing and Shanghai in China. as a sample, 1381 female women was seleted for development of apparel sizing system. Thus, this study was to characterize body types of Chinese adult female by classifying them into groups and set coverage rate of ready-made clothes by developing an apparel sizing system according to the Women's Wear Specifications(GB/T 1335.2-1997), National Standards of People's Republic of China. As for the method of this study was done during Jun. 23 $\sim$ Aug. 7, 2004. Data analysis were processed by SPSS WIN 10.0 Program was used to for technical statistical analysis. The result was as follows: The clothes dimension for upper and lower body and the coverage rate of body size that had the highest appearance ratio from the entire group was Y-type 160-84$\cdot$160-64(4.6%) and the section 160cm 32.4%, A-type 160-88$\cdot$160-72(3.3%) and the section 160cm 28.1%, B-type 155-88$\cdot$155-78(3.8%) and the section 155cm 27.8%, C-type 150-96$\cdot$150-88(2.5%). The result By setting of representative size number and production coverage rate for Chinese adult female. The representative size number of the entire group was set for 150-80A$\cdot$150-64A(1.0%), 155-84A$\cdot$155-68A(2.6%), 160-88A$\cdot$160-72A(3.3%), 165-84A$\cdot$165-68A (2.8%), 170-96A$\cdot$170-80A(0%). The production coverage rate for each representative size number was SS size the section 150cm 2.8%, size the section 155cm 17.0%, M size the section 160cm 31.6%, L size the section 165cm 25.0%, XL size the section 170cm 12.6% that covered 85.0%.

• Journal of Fashion Business
• /
• v.12 no.4
• /
• pp.56-72
• /
• 2008

The purpose of this study was to provide with the useful fundamental data by developing the appearl sizing system according to body types for the Women's Wear Specifications(GB/T 1335.2-1997), National Standards of People's Republic of China. Thus, it was to improve of the garment fit and coverage rate for the apparel production assortment and stock of exporting domestic clothing to China. For this study, 581 female women aged in their twenties who lived in Beijing and Shanghai were selected for the development of the apparel sizing system who resident in Beijing and Shanghai in China. As for the method of this study was made three primary items(length, bust girth, waist girth) and seven secondary items. Data analysis were processed by SPSS WIN 10.0 Program was used. The research selected 3 major body measurements, such as stature, bust girth, waist girth and 7 secondary measurements to investigate the body features of the Chinese adult women. The data throughout the study were analyzed by using SPSS WIN version 10.0 S/W. The result were as follows: The clothes dimensions for upper and lower body and the coverage rate of body size that had the highest appearance ratio from the selected age group in 20's were: Y-type 160-84 155-64(5.9%) and the section 160cm 22.6%, A-type 160-80 160-62(39%) and the section 160cm 27.9%, B-type 155-80 155-66(6.2%) and the section 160cm 24.7%. The representative size codes of the Chinese adult women aged in their 20's were set for representing certain body dimensions such as 150-76A 150-60A(0.0%), 155-80A 155-64A(2.4%), 160-84A 160-68A(3.9%), 165-88A 165-72A(0.3%), 170-92A 170-76A(0.0%). The production coverage rates for the each representative size codes were S size the section 150cm 1.5%, M size the section 155cm 15.3%, L size the section 160cm 36.0%, XL size the section 165cm 29.7%, XXL size the section 170cm 11.4% that covered 93.9%.

• Journal of Korean Society of Transportation
• /
• v.27 no.1
• /
• pp.17-25
• /
• 2009

This research analyzed the changes of drivers' visual workload with beta wave of bionic signals from brain's occipital lobe from entrance to exit section of the Yuksimnyeong tunnel which is 3.1km long in Daejeon-Tongyeong section of Jungbu expressway. There are 10 subjects who Participate our experiments and the results are as follows. First. the drivers' visual workload is higher about 41% in entrance section of the tunnel than 200m in advance of the section of the tunnel. Second, it is higher than 200m in advance of the section of the tunnel by 34.5% that the value of the drivers' visual workload who is driving in the tunnel. Third, as a result of analyzing the tunnel into 200m unit section, it is statistically different from other sections' at the 1.0km and 2.4km section from the entrance of the tunnel. If drivers sustain average visual workload for safe driving in very long tunnel, it's not desirable environment that drivers' visual workload goes under the average workload. Therefore, it would be the section where drivers who is driving in tunnel could cause a traffic accident.

• Transactions of the Korean Society of Mechanical Engineers
• /
• v.2 no.3
• /
• pp.53-61
• /
• 1978

This study has been concentrated on the relations between the crack growth rate and the stress intensity factor, the fatigue limit and finally on the condition of the crack propagation along the laminated cross section of the laminated steel under the repeated plane bending through tests. The following results are obtained. 1. The fatigue limit of the laminated steel is higher than the single steel 2. The realtion between the fatigue crack growth rate, dL/dN and Stress intensity factor are ; dL/dN = 2.14 * 10$^{-11}$ $K^{2.95}$ for SUP 9 dL/dN = 1.70 * 10$^{-11}$ $K^{2.95}$ for SMS dL/dN = 9.77 * 10$^{-11}$ $K^{2.95}$ for SPMS dL/dN = 3.57 * 10$^{-8}$ $K^{1.53}$ for SPMM dL/dN = 5.5O * 10$^{-8}$ $K^{1.53}$ for MLD 3. The crack propagation of the laminated steel also tends to be completed through 3 steps; The first step proceeds swiftly, in a second slowly for a long time and last very rapidly for a short moments.