• Journal of the Korean Geotechnical Society
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• v.38 no.7
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• pp.49-62
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• 2022

The hollow modular concrete block reinforced foundation method is one of the ground reinforcement foundation methods that uses hexagonal honeycomb-shaped concrete blocks with mixed crushed rock to reinforce soft grounds. It then forms an artificial layered ground that increases bearing capacity and reduces settlement. The hollow modular honeycomb-shaped concrete block is a geometrically economical, stable structure that distributes forces in a balanced way. However, the behavioral characteristics of hollow modular concrete block reinforced foundations are not yet fully understood. In this study, a bearing capacity test is performed to analyze the reinforcement effectiveness of the hollow modular concrete block through the laboratory model tests. From the load-settlement curve, punching shear failure occurs under the unfilled sand condition (A-1-N). However, the filled sand condition (A-1-F) shows a linear curve without yielding, confirming the reinforcement effect is three times higher than that of unreinforced ground. The bearing capacity equation is proposed for the parts that have contact pressure under concrete, vertical stress of hollow blocks, and the inner skin friction force from horizontal stress by confining effect based on the schematic diagram of confining effect inside a hollow modular concrete block. As a result of calculating the bearing capacity, the percentage of load distribution for contact force on the area of concrete is about 65%, vertical force on the area of hollow is 16.5% and inner skin friction force of area of the inner wall is about 18.5%. When the surcharge load is applied to the concrete part, the vertical stress occurs on the area of the hollow part by confining effect first. Then, in the filled sand in the hollow where the horizontal direction is constrained, the inner skin friction force occurs by the horizontal stress on the inner wall of the hollow modular concrete block. The inner skin friction force suppresses the punching of the concrete part and reduces contact pressure.

• Journal of Korean Society of Disaster and Security
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• v.6 no.3
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• pp.35-42
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• 2013

The purpose of this research is to systematize safety management for practical application through analysis and review of several safety standards currently in force among the statutes and rules regarding various safety accidents. Accordingly, the safety standard systems of Japan, US, and Germany were examined and a KOSAM entity relationship diagram (ERD) was drawn based on the ontology system. The ERD consists of the safety standard scope, safety management statute, safety management standard, safety management subjects, causes of safety accidents, and safety management organization entities. Next, each entity was assigned a code and finally a KOSAM safety management condition search screen was designed based on the ERD. This research is expected to bring an overall improvement in safety standard management and operation through safety standard DB construction and the execution of safety management system development.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.11a
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• pp.993-996
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• 2008

Compression stress block used to concrete structure design substitutes equivalent triangle, rectangle, trapezoid and parabola-rectangle stress block for actual concrete stress distribution. Its shape is different in design code of the major advanced countries. It reflects the material feature of each of country. Presently, compression stress block of korea concrete design code is equal to it of ACI code that doesn't reflect the material feature of the high strength concrete. So, many research conclusions showed that it is not reasonable. The study compares concrete stress blocks of the major advanced countries and does an experiment on concrete compression stress block to know the material feature of the concrete in korea. It obtains the operating load and the concrete strain in experiment and draw stress block parameters. It compares stress block parameters applied to design code with those by the experiment conclusion. In addition, It compares and analyses nominal axial force-moment diagram by the stress block of the major advanced countries.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.34 no.8
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• pp.965-970
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• 2010

Bolts and nuts are widely used to fasten mechanical parts together in machines and structures. The primary role of a nut is to maintain the axial force of a bolt. In this paper, a new type of a lock nut that uses a spring is studied. To have a spring within a nut, a cocking process to narrow the top of the nut is adopted, but cracking occurred in the process. In this study, strain of an initial model is measured using the finite element analysis program, MSC/Marc. The occurrence of the crack was studied by comparing the maximum observed strain of a model with the maximum strain indicated by an accurate stress-strain diagram of 1020 steel. Then, the structure of the lock nut was optimized by response surface analysis to prevent cracking. The prototype of the lock nut was manufactured on the basis of the optimization result, and cracking did not occur.

• Journal of the Earthquake Engineering Society of Korea
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• v.7 no.6
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• pp.81-91
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• 2003

Recently, many high-rise reinforced concrete(RC) bearing-wall structures of multiple uses have been constructed, which have the irregularities of weak(or soft) story and torsion at the lower stories simultaneously. The study stated herein was performed to investigate seismic performance of such a high-rise RC structure through a series of shaking table tests of a 1: 12 model. Based on the observations of the test results, the conclusions are drawn as follows: 1) Accidental torsion due to the uncertainty on the properties of structure can be reasonably predicted by using the dynamic analysis than by using lateral force procedure. 2) The mode coupled by translation and torsion induced the overturning moments not only in the direction of excitations but also in the perpendicular direction: The axial forces in columns due to this transverse overturning moment cannot be adequately predicted using the existing mode analysis technique, and 3) the hysteretic curve and the strength diagram between base shear and torque(BST) clearly reveal the predominant mode of vibrations and the failure mode.

• Journal of Science and Technology Studies
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• v.11 no.2
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• pp.67-96
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• 2011

Studies in scientific visualization have disclosed a visual chain among many scientific visualizations, which starts from the photographs that have many details to diagrams that enable scientists to make specific claims due to their abstract characters. Located at both ends of the visual chain, photographs and diagrams are regarded as being different kinds and having different characteristics. The photographs - or microphotographs to be precise - that this paper discusses, however, had been removed of unnecessary details and were prepared with carful attention to illustrative functions that diagrams usually perform. Following microphotographic changes in a Korean laboratory, this article shows that the knowledge of specimen preparation was transmitted from an American leading group to the Korean laboratory through a direct contact, and that with this, the technique of taking microphotographs of the laboratory was much improved. The specimen preparation method is, however, a tacit knowledge that is invisible in both group's papers. This article argues that the method of specimen preparation is the driving force that made the microphotographs act like carefully prepared diagrams and acquire objectivity.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.18 no.6
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• pp.571-575
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• 2005

In order to improve the efficiency of dye-sensitized solar cell (DSSC), $TiO_2$ electrode screen-printed on transparent conducting oxide (TCO) substrate was sintered in variation with different temperature$(350\;to\;550^{\circ}C)$. $TiO_2$ electrode on fluorine doped tin oxide (FTO) glass was assembled with Pt counter electrode on FTO glass. I-V properties of DSSCs were measured under solar simulator. Also, effect of sintering temperature on surface morphology of $TiO_2$ films was investigated to understand correlation between its surface morphology and sintering temperature. Such surface morphology was observed by atomic force microscopy (AFM). Below sintering temperature of $500^{\circ}C$, efficiency of DSSCs was relatively lower due to lower open circuit voltage. Oppositely, above sintering temperature of $500^{\circ}C$, efficiency of DSSCs was relatively higher due to higher open circuit voltage. In both cases, lower fill factor (FF) was observed. However, at sintering temperature of $500^{\circ}C$, both efficiency and fill factor of DSSCs were mutually complementary, enhancing highest fill factor and efficiency. Such results can be explained in comparison of surface morphology with schematic diagram of energy states on the $TiO_2$ electrode surface. Consequently, it was considered that optimum sintering temperature of a-terpinol included $TiO_2$ paste is at $500^{\circ}C$.

• Journal of Fashion Business
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• v.24 no.4
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• pp.117-129
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• 2020

Just as the name 'aesthetics' implies, the meaning of 'aisthesis' or 'sense' in Greek, is perceived as an important element in modern social design. Gilles Deleuze emphasized sensory expression over the rational side of the body, and argued for sensory theory, which is the theory of how painting produces new senses. The purpose of this study was to theoretically examine the sensory theory of Deleuze, which has given new value to the senses, apply it to analyze the body expression method shown in the Iris van Herpen collection, and derive its aesthetic characteristics. In his sensory theory, Deleuze argued that the senses can be expressed by the embodiment of force and rhythm, and one can only create art through the senses. To develop one's philosophical logic through Bacon's painting, we divided it into Hysteria, Cops sans organs, Diagram, Becoming, and Paired figures. Based on these analyses, the visualization of the senses in Iris van Herpen fashion resulted in hysteria, organ-free body, diagrams, and heterogeneity combinations. Analysis of the method of expression revealed rhythmicity, atypicality, scalability, and reproducibility as expression characteristics. Applying Deleuze's sensory theory to access experimental Iris van Herpen's fashion could confirm that there was an open system's accessibility. Deleuze's sensory theory, which has given a new value to the senses, will further help to understand modern fashion design in a wide and diverse way and discover the intrinsic value within it.

• Korean Medical Education Review
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• v.10 no.2
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• pp.25-44
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• 2008

Objectives: Through using of the strong research method like a Randomized Controlled Trial: RCT, we have to heighten quality of Medical Education study. I'd like to introduce "CONSORT", which stands for Consolidated Standards of Reporting Trials. Contents: Preventive Service Task Force(200l) in USA proposed Levels of evidence for enlarging evidence-based Practice: EBP. And the CONSORT was introduced, which encompasses various initiatives developed by the CONSORT Group to alleviate the problems arising from inadequate reporting of randomized controlled trials (RCTs). the CONSORT has 13 guides like these: 1. How participants were allocated to interventions 2. Scientific background and explanation of rationale 3. Eligibility criteria for participants. The settings and locations where the data were collected. 4. Precise details of the interventions intended for each group and how and when they were actually administered 5. Specific objectives and hypotheses 6. Clearly defined primary and secondary outcome measures, When applicable. any methods to enhance the quality of measurements (e.g., multiple observations, training of assessors) 7. How sample size was determined. When applicable, explanation of any interim analyses and stopping rules 8. Method used to generate the random allocation sequence, Details of any restriction [of randomization] 9. Method used to implement the random allocation sequence 10. Who generated the allocation sequence, who enrolled participants. and who assigned participants to their groups 11. Whether or not participants, those administering the interventions, and those assessing the outcomes were blinded to group assignment. If done, how the success of blinding was evaluated 12. Statistical methods used to compare groups for primary outcome(s), Methods for additional analyses, such as subgroup analyses and adjusted analyses 13. Flow of participants through each stage (a diagram is strongly recommended) Specifically, for each group report the numbers of participants randomly assigned. receiving intended treatment, completing the study protocol. and analyzed for the primary outcome. Results and Conclusion: Randomized Controlled Trial: RCT guided of CONSORT will contribute to do stronger evidence-based medical studies.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.20 no.4
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• pp.1263-1274
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• 1996

In this paper, as elastic-plastic fracture toughness test under mixed mode loading was proposed using a single edge-cracked specimen subjected to bending moment(M), shearing force(F), and twisting moment(T). The J-integral of a crack in the specimen is expressed in the form J=$J_I$+ $J_II$$J_III$, where $J_I$, $J_II$ and $J_III$ are the components of mode I, mode II and mode III deformation, respectively. $J_I$, $J_II$ and $J_III$ can be estimated from M-$\theta$ ($\theta$;crack opening angle), F-U(U; crack shear displacement) and T-$\alpha$ ($\alpha$;crack twisting angle). In order to obtain the the M<-TEX>$\theta$, F-U and T-$\alpha$ diagram inreal time, a new deformaiton gage for mixed mode loading was proposed using the optical position sensing device(PSD). The elastic-plastic fracture toughness test was carried out with an aluminum alloy. The loading apparatus was designed and manufactured for this experiment. For the loading condition of the crack initatio in the mixed mode, the MMT -3(mode I+ mode II+ mode III) has the lowest values out of the all specimens. This implies that MMT-3 is possible of the crackinitation at lower load, if the specimen acts on together with the torque under the same loading condition. An elastic-plastic fracture toughness test using the PSD brings a successful experimentation in measuring the crack deformation(mode I+ mode II+ mode III).