• KIEAE Journal
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• v.7 no.4
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• pp.147-152
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• 2007

Numerous non-destructive tests(NDT) to assess the safety of real structures have been developed. System identification(SI) techniques using dynamic responses and behaviors of structural systems become an outstanding issue of researchers. However the conventional SI techniques are identified to be non-practical to the complex and tall buildings, due to limitation of the availability of an accurate data that is magnitude or location of external loads. In most SI approaches, the information on input loading and output responses must be known. In many cases, measuring the input information may take most of the resources, and it is very difficult to accurately measure the input information during actual vibrations of practical importance, e.g., earthquakes, winds, micro seismic tremors, and mechanical vibration. However, the desirability and application potential of SI to real structures could be highly improved if an algorithm is available that can estimate structural parameters based on the response data alone without the input information. Thus a technique to estimate structural properties of building without input measurement data and using limited response is essential in structural health monitoring. In this study, shaking table tests on three-story plane frame steel structures were performed. Out-put only model analysis on the measured data was performed, and the dynamic properties were inverse analyzed using least square method in time domain. In results damage detection was performed in each member level, which was performed at story level in conventional SI techniques of frequency domain.

• Journal of Preventive Medicine and Public Health
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• v.7 no.2
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• pp.395-401
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• 1974

In order to figure out the normal range, lower limit of hypertension and upper limit of hypotension of the blood pressure of Korean, authors had measured blood pressure according to Korotkow's method for 31,897 healthy persons as samples who were occupied different levels of the social class except cases who would seem to be the essential hypertension and had the diseases affecting to secondary hypertension. A following conclusion was induced by actual measurement and statistical reasoning. 1. The normal range and limits of hypo- and hypertension by sex and age groups of Korean were demonstrated in Table 1 and Figure 1. 2. The more aging the higher value of blood pressure in both sexes, especially women rather than men and systolic as to diastolic. 3. Generally, blood pressure values of female were lower than male, after 55 years of age, however, the crossing phenomenon was recognizable. 4. To settle the normal and abnormal ranges of the blood pressure of Korean, it was attempted that $M{\pm}1.282{\sigma}$ as normal range, $M+2{\sigma}$ as lower limit of hypertension and $M-2{\sigma}$ as upper limit of hypotension were calculated, and regression lines were drawn to adjust the biological variables and derive continuity from each age class. (Fig. 2 and 3) 5. The blood pressure levels were becoming elevated as to getting increased of the body weight, particularly diastolic value at 40-49 age group in male and systolic value at 30-39 age group in female.

• Journal of the Korean Society for Nondestructive Testing
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• v.28 no.2
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• pp.217-224
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• 2008

Trusses are found in many common structures such as bridges and buildings. The truss is a fundamental design element in engineering structures and it is important for an engineer to apply the truss design to engineering structures by understanding the mechanics of truss element. In an experimental course, the experiment selves as an example of the usefulness of the Wheatstone bridge in amplifying the output of a transducer. With the apparatus described here, it is possible to obtain experimental measurements of forces in a truss member which agree within errors to predictions from elementary mechanics. The apparatus is inexpensive, easy to operate, and suitable as either a classroom demonstration or student laboratory experiment. This device is a small table-top experiment. The conventional strain measuring device is costly and complicated - it is not simple to understand its structure. Hence, strain gage and the A/D converter are assembled to come up with a load and a strain measuring device. The device was tested for measuring the strain in a loaded specimen and the results were compared to those predicted by theory of mechanics.

• Smart Structures and Systems
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• v.8 no.5
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• pp.501-524
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• 2011

Recent studies have discovered that a conventional passive isolation system may suffer from an excessive isolator displacement when subjected to a near-fault earthquake that usually has a long-period velocity pulse waveform. Semi-active isolation using variable friction dampers (VFD), which requires a suitable control law, may provide a solution to this problem. To control the VFD in a semi-active isolation system more efficiently, this paper investigates experimentally the possible use of a control law whose control logic is similar to that of the anti-lock braking systems (ABS) widely used in the automobile industry. This ABS-type controller has the advantages of being simple and easily implemented, because it only requires the measurement of the isolation-layer velocity and does not require system modeling for gain design. Most importantly, it does not interfere with the isolation period, which usually decides the isolation efficiency. In order to verify its feasibility and effectiveness, the ABS-type controller was implemented on a variable-friction isolation system whose slip force is regulated by an embedded piezoelectric actuator, and a seismic simulation test was conducted for this isolation system. The experimental results demonstrate that, as compared to a passive isolation system with various levels of added damping, the semi-active isolation system using the ABS-type controller has the better overall performance when both the far-field and the near-fault earthquakes with different PGA levels are considered.

• Physical Therapy Korea
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• v.25 no.4
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• pp.46-52
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• 2018

Background: The hamstring muscles in the lower extremity are highly important for knee joint stability and can be classified into medial and lateral hamstrings according to the anatomical position, which have some different functions. To measure the strength of the individual hamstring muscles, manual muscle testing is clinically performed by dividing rotation postures into internal and external postures. However, this has no sufficient scientific background. Objects: This study aimed to test the difference that the tibial rotation would cause in the muscle activity of the medial and lateral hamstrings. Methods: The muscle activities of the biceps femoris, semitendinosus, and semimembranosus were measured in a total of three different postures (neutral position and internal and external rotations) with 3 replications. During the maximal isometric contraction, resistance was constantly provided by the string attached to the strap, not by manual resistance of the examiner. Before and after electromyography measurements, the participants underwent hamstring flexibility measurement using the active knee extension test in the supine position on the treatment table. Results: The semitendinosus had a 12.56% reduction in muscle activity in external rotation as compared with that in neutral position. The biceps femoris and semimembranosus showed reduced muscle activities in both external and internal rotations as compared with those in neutral position. Only the women showed significant decreases in the comparison between pre and post-active knee extension. Conclusion: Only the semitendinosus muscle was consistent with the anatomical speculation. However, the reduction in the muscle activity of the semitendinosus as compared with that in neutral position was only 12.56%, the clinical value of which may be difficult to justify.

• Journal of the Korean Geosynthetics Society
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• v.11 no.1
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• pp.23-33
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• 2012

The stability of urban railway foundation can be a problem due to the excessive settlement. The settlement at the base of railway is monitored by the installed settlement gauges. The piezometer and pore water pressure measurement device are installed to measure the variation of pore water pressure and ground water table during the continuous pullout of sheet piles which were used for the braced cut. The settlement of railway is predicted with using the computer program CAIN RDA. The input data for the numerical analysis are obtained from the field soil exploration data and soil properties. The surcharged load from landscaping over the ground surface and the weight of train are taken into account for the estimation of settlement. As a result of numerical analysis, the range of settlement for six different Sites is from 5.94 cm to 12.77 cm. Thus, the settlement level at Site 2 is occurred 12.77 cm which is higher than the allowable settlement of 10 cm.

• Journal of the Korean Society of Costume
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• v.47
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• pp.61-72
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• 1999

For the establishment of ready made Hanbok for the people in their 20's this study aims to develope Bagi-chogori pattern that revives the esthetic quality of the traditional Hanbok as well as comfortably fit the body. Direct method was used in Measuring the 33 parts of men which was selected as items needed for the analysis of the body and the development of patterns. In accordance with the body measurement and the analysis of the result the bust girth and height which has interrelation was chosen as the standard size for the development of pattern. Men's Baji-chogori(Korean traditional Jacket and Pants) which doesn't request fitness for instance we drew out a cross table by giving 5cm intervals each for breast waist hip girth and height. Size system of Baji-chogori was 4 steps. 1st was bust 95cm height 165cm 2nd was bust girth 95cm height 170cm 3rd was bust girth 100cm height 175cm and the 4th was bust girth 105cm height 180cm. In the case of Men the grouping of bodies was attempted by concentrating on the difference of the drop amount(Bust girth to hip girth), However 90% of men in their 20's showed a silhouette of an inverted triangle. Therefore attempt for an additional grouping wasn's Only calculation concerning the ease amount of items such as bust which and length was considered to enhance the silhouette of Hanbok when worn. Men's body for instance have a tendency to change to a rectangular shape as they get older. specially the abdominal girth trend to increase greatly. So study and development of pattern should be made for all age groups.

• Journal of KIISE:Computer Systems and Theory
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• v.30 no.12
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• pp.724-735
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• 2003

In recent high-performance superscalar processors, the result value of an instruction is predicted to improve instruction-level parallelism by breaking data dependencies. Using those predicted values, instructions are speculatively executed and substantial performance can be gained. It, however, requires additional power consumption due to the frequent access and update of the value prediction table. In this paper, first, the trade-off between the performance improvement and the increased power consumption for value prediction is measured and analyzed. And, in order to reduce additional power consumption without performance loss, the technique of controlling speculative execution with confidence counter and predicting useful instructions is developed. Also, in order to prove the validity, a tool is developed that can simulate processor behavior at cycle-level and measure total energy consumption and power consumption per cycle.

• Journal of Korea Technology Innovation Society
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• v.16 no.2
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• pp.391-407
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• 2013

The paper tests the embodiment hypothesis by measuring the technological obsolescence of a specific year (1990)'s technology and investigating the relationship between labor productivity and technological obsolescence. This approach is based on Salter (1969) that emphasizes the economic aspect of technology. We use the rate of economic surplus as the proxy of technological obsolescence for 10 main industries, including food processing, textiles, chemicals, non-steel metals, steels, metal products, machinery, electronics, precision machinery, and transportation equipments. The result shows that the embodiment hypothesis is not accepted for the overall manufacturing sector. However, we found the vintage effect - a positive relationship between technological obsolescence and labor productivity over time - in textiles, chemicals, non-steel metals, metal products, electronics, and transportation equipments. Therefore, the government should support R&D investment as well as capital equipments investment for the industries with large vintage effect.

• Journal of the Korean Society of Physical Medicine
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• v.8 no.2
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• pp.183-192
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• 2013

PURPOSE: The purpose of this study was to research the effect of self-Stretching Exercise on musculoskeletal Symptom and job Stress for care helpers who work at geriatric hospital and come up to NIOSH standard. METHODS: The effect of self-Stretching Exercise was measured using 'musculoskeletal symptom survey table' and 'Job stress measurement scale for korean' from the Korea Occupational Safety and Health Agency(KOSHA) for 40 care helpers. The paired t-test and independent t-test was used for statistical analysis. RESULTS: The pracitce of Self-Stretching Exercise was showed significant effect reducing the stress for care helper's total job Stress and inappropriate compensation, job instability, job requirement, relationship conflict, physical environment(p<.05), and significant difference for their total score, relationship conflict, structure and organization, physical environment, inappropriate compensation improvement on variations on job stress in groups(p<.05). However, self-Stretching Exercis was showed no significant effect on physcial burden. CONCLUSION: The self-Stretching Exercise was the most effect way to reduce Musculoskeletal Symptom and job Stress for a care helpers through the guidance of physical therapist.