• Korean Journal of Microbiology
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• v.38 no.1
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• pp.7-12
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• 2002

The intergenic spacer (IGS) region of the ribosomal DNA of species in Fusarium section Liseola was analyzed by amplification and subsequent digestion with several restriction enzymes. The length of the amplified IGS region was about 2.6 Kb in all strains except F.moniliforme 12 Which was about 2.9 Kb. The enzymes, EcoRI, HincII, SalI, HindIII, PstI and SmaI, digested the IGS region and nine haplotypes were identified among 11 strains. In the dendrogram based on PCR-RFLP of IGS region combined the results of section Liseola in this study and section Elegans in previous study, variation in the IGS appears to offer considerable potential to resolve intraspecific relationship as well as interspecies or intersection.

• Steel and Composite Structures
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• v.26 no.1
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• pp.31-44
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• 2018

This paper reports a novel steel beam-to-column connection suitable for use in the weak axis of I-section column. Monotonic and cyclic loading experimental investigations and numerical analysis of the proposed weak-axis connection were conducted, and the calculation procedure of the beam-column relative rotation angle and plastic rotation angle was developed and described in details. A comparative analysis of mechanical property and steel consumption were employed for the proposed I-section column weak-axis connection and box-section column bending connection. The result showed that no signs of fracturing were observed and the plastic hinge formed reliably in the beam section away from the skin plate under the beam end monotonic loading, and the plastic hinge formed much closer to the skin plate under the beam end cyclic loading. The fracture of welds between diaphragm and skin plate would cause an unstable hysteretic response under the column top horizontal cyclic loading. The proposed weak-axis connection system could not only simplify the design calculation progress when I-section column is adopted in frame structural design but also effectively satisfy the requirements of 'strong joint and weak member', as well as lower steel consumption.

• Journal of the Korea institute for structural maintenance and inspection
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• v.10 no.6
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• pp.143-153
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• 2006

The paper presents the results of a study on improvement in flexure capacities of continuous prestressed steel I-girder with section increasement at internal supports. After tensioning, the field experiment on prestressed steel I-girder has been performed in the various aspects of prestressed I-girder introducing section increasement at internal supports, tendon profile.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2000.04b
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• pp.51-58
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• 2000

Lateral buckling behavior of laminated composite thin-walled I-section beams subjected to bending moment is investigated by applying the nonlinear anisotropic thin-walled beam theory. The constituent laminated thin-walled elements of I-section are assumed to be symmetrically laminated. The bending, twisting, and warping stiffnesses of the cross section are obtained based on the definitions of these stiffnesses In the thin-walled anisotropic beam theory In numerical examples, singly-symmetric I-beams with specially orthotropic, quasi-isotropic, angle-plys and various boundary conditions are considered. To validate the proposed theoretical approach, present analytical solutions are compared with three dimensional finite element solutions.

• Korean Journal of Occupational Health Nursing
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• v.7 no.2
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• pp.130-135
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• 1998

To investigate the working characteristics of the workers by place of duty, a study was carried out among 591 male workers aged 20-55 employed in an automobile industry in Korea. Workers participated to this study were divided into low back pain(LBP) and control group, according to the self-reports by written questionnaires. Work factors and complaint rates of low back pain were compared to the work places. The results were as follows ; 1) The complaint rates of low back pain were 49.2%(292 men) as a whole, 58.6%(34 men) in Production Control Department I, 50.2%(120 men) in Stamping Tool Department, 46.9%(138 men) in Bus Department. 2) Lifting and earring work of individual workers were directly associated with low back pain. Frequency of lifting and carring work is higher in the Final Body Section(Production Dept. I) and Body I Section(Bus Dept.). 3) LBP group were more frequently involved in working in awkward position(Quality Control Section of Stamping Tool Dept.), bending(Body I Section of Bus Dept.) and twisting posture(Sash Section and Body I Section of Bus Dept.). 4 )Workers exposed to vibration during working shows the higher complaint rate of low back pain.

• Journal of Korean Academy of Nursing
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• v.20 no.2
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• pp.131-141
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• 1990

Recently, the rate of cesarean section in Korea has been increasing. The results of several previous studies in foreign countries on the emotional responses of cesarean section mothers showed that they might experience difficulties in the mother- infant interaction due to fatigue, lack of early mother - infant interaction, disappointments, anger, feelings of loss of control, and other factors. Human behavior is said to be determined by one's self concept, and self concept is influenced by both internal and external environmental factors. A scale to measure the self concept of cesarean section mothers was needed in order to identify those who might have difficulties in the mother- infant interactions in future. The purposes of this study were to develop a measuring scale, and to test its reliability and validity. The process of this study was as follows. A structured interview was done with 50 cesarean section and vaginal delivery mothers to find their state of emotional reaction after giving birth to their babies. Based on the results of the interviews, a 50 items Likert scale was developed. The self concept of 268 cesarean section and vaginal delivery mothers who were hospitalized at six hospital in seoul were measured, during the period between Feb. 1 and April 30. Reviewing the discriminating power of each item by means of crosstabulation, ten items were selected for the final scale. The reliability and validity of this ten item scale were tested by Cronbach's alpha and t-test, using spss pc＋package. The results of this study and recommendation are as follows. 1. The ten selected items were as follows. I feel pains in my breast. (－) I have a good appetite now. (＋) I feel pains in my flank. (－) I feel fine now. (＋) My body seems to have returned to its prepregnant state. (＋) Thinking of the delivery process, I feel sorry. (－) I want to hold my baby in my arms. (＋) I want to keep my own life, even if I became a mother. (－) I want to delegate the care of the baby to my mother / mother in law. (－) I think baby is my alter ego. (＋) 2. The reliability of this scale was tested by Cronbach's alpha, and the coefficient of this scale was .8066. 3. The construct validity of this scale was tested by means of known group methods. The value of self concept for cesarean section mother was significantly lower than for vaginal delivery mothers(t＝-5.51, df＝266, p＝0.007). 4. The criterion validity of this scale was tested indirectly. Though this scale could discriminate the differences in the self concept between cesarean section and vaginal delivery mothers, the five items on the personal self concept scale didn's show any differences between cesarean section and vaginal delivery mothers. Therefore, the study indicates that those who shows lower values in the personal self concept measurement, that is, lower than 12.03 points, could be regaled as “risk mothers” 5. Further studies using this scale to clarify the influencing factors on negative self concept are strongly recommended.

• Steel and Composite Structures
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• v.4 no.5
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• pp.367-384
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• 2004

A numerical model based on the finite element technique is adopted to investigate the behavior and strength of thin-walled I-section beam-columns. The model considers both the material and geometric nonlinearities. The model results were first verified against some of the currently available experimental results. A parametric study was then performed using the numerical model and interaction diagrams for the investigated beam-columns have been presented. The effects of the web depth-to-thickness ratio, flange outstand-to-thickness ratio and bending moment-to-normal force ratio on the ultimate strength of thin-walled I-section beam-columns were scrutinized. The interaction equations adopted for beam columns design by the NAS (North American Specifications for the design of cold formed steel structural members) have been critically reviewed. An equation for the buckling coefficient which considers the interaction between local buckling of the flange and the web of a thin-walled I-section beam-column has been proposed.

• Composites Research
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• v.34 no.5
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• pp.323-329
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• 2021

In this paper, the characteristics of fracture in mode I loading were analyzed for adhesively bonded joints with non-uniform adhesion. The Double Cantilever Beam test was performed and mode I fracture toughness was obtained. In the case of non-uniform adhesively bonded joints, the stable crack growth sections and unstable crack growth section were shown. The fracture characteristics of each section were observed through the load-displacement curve of the DCB test and the fracture surface of the specimen. Finite Element Analysis was performed at the section based on segmented section by crack length measured through the test and using the mode I fracture toughness of each section. Through DCB test results and finite element analysis results, it was confirmed that the fracture behavior of specimens with non-uniform adhesion can be simulated.

• Korean Journal of Computational Design and Engineering
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• v.14 no.4
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• pp.234-241
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• 2009

The use of aluminum parts in automobile structuraI applications has increased in an effort to reduce the weight of cars and hence improve fuel economy. But Aluminum bar, I-beam and channels need other processes to vary the cross section in the axial direction. Thus, applications of these parts are limited by high cost. If the cross section of the part is variable by using only extrusion, application of extruded bar, I-beam and channels will increase in the Aluminum industries. In this paper, we propose the variable-shape extrusion process which can control the thickness of Aluminum bar. And we can calculate the speed of center ram by varying the cross section in the extrusion to control the thickness of Aluminum bar.

• Structural Engineering and Mechanics
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• v.10 no.5
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• pp.479-489
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• 2000

Based on the stiffness equation of the tapered beam element involving the effects of axial force and shear deformation, numerical investigations are carried out on elastic instability for web-linearly tapered columns with I-section of steel portal frames. Effects of shear deformation on the effective length of the tapered columns with I-section are studied. An efficient approach for determining the effective length of the tapered portal frame columns considering effects of shear deformation is proposed.