• KSCE Journal of Civil and Environmental Engineering Research
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• v.8 no.1
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• pp.87-95
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• 1988

In the arctic offshore regions, massive offshore gravity platforms are recommended to be construced because of severe environments. In such structures which is so large that its characteristic length is of the order of the wave length, wave-structure interaction problem has been solved using linear diffraction theory. Structural analysis of the large scale offshore structures requires wave force distribution along depth and wave pressure distribution on the body surface. In this study, existing computer program which calculates the total wave force acting on axisymmetric bodies has been modified to calculate wave force distribution along depth and wave pressure distribution on the body surface. Numerical results of pressure distribution for a fixed vertical cylinder obtained from this analysis has been compared with the results of an analytic solution of MacCamy-Fuchs, and good agreements has been obtained. It is desirable to use 6 in the case of analytic solution, and 5 in the case of numerical solution as the Fourier Mode of Green function. The results in this study are expected to be utilized for structural analysis such as pseudo-static analysis, dynamic analysis and fatigue analysis.

• The Journal of Pediatrics of Korean Medicine
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• v.12 no.1
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• pp.133-143
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• 1998

Myofascial pain syndrome is one of the pain syndrome resulted from myofascia which covered muscles and clinically characteristic feature by sensitive trigger point in skeletal muscles and referred pain reactivated by stimulating each trigger point. The origin of headache are local lesion such as head, chest, abdominal organ, systemic lesion with fever or in toxic state. the other factors are consciousness, personality, anxiety, depression, which cause muscle strain in physiological environment. The Oriental Medical therapy for headache has herb medication and acupuncture. especially acupuncture therapy has not only classical systemic acupuncture(體鍼) but also neo-acupuncture(新鍼) such as commonly using auricular acupuncture(耳鍼) and manual acupuncture (手鍼), recently trigger point acupuncture is used. The author analyzed 27 cases of patient with headache treated by trigger point acupuncture therapy in Dong-yu Oriental Medical Hospital from March 1st 1997 to February 28th 1998. The following results were obtained. 1. The sex ratio of the female was 59.26%(16 cases) and male was 40.74%(11 cases), the ratio of high school student was 62.96%(17cases) as first. 2. The headache duration ratio of 2-3 years was 37.04%(10 cases) as first, 1-2 years was 25.93%(7 cases) as second. 3. The portion ratio of whole headache was 33.33%(9 cases) as first, lateral headache was 29.63%(8 cases) as second 4. The combined symptoms ratio of anorexia was 40.74%(11 cases) as first, fatigue was 33.33%(9 cases) as second, neck stiffness and dizziness was each 25.93%(7 cases) as third. 5. The therapeutic duration ratio of below 1 week was 29.63%(8 cases) as first, 2-3 weeks was 22.22%(6 cases) as second, 1-2 weeks and 3-4 weeks was each 18.52%(5 cases) as third. 6. The ratio of family history was 11 cases(40.74%). mother with headache was 6 cases, father was 3 cases, and brothers & sisters was 2 cases. 7. The herb medication ratio of Chungsanggyuntongtang(淸上?痛湯) was 37.04%(10 cases), Kamiondamtang(加味溫膽湯) was 22.22%(6 cases), Hyangsapyunguisan(香砂平胃散) was 18.25%(5 cases) etc. 8. The remedial effect ratio of good was 25.93%(7 cases), fair was 48.15%(13 cases), not improved was 7.41%(2 cases), side effect was 3.70%(1 cases), and unknown was 14.81%(4 cases).

• Transactions of the Korean Society of Mechanical Engineers A
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• v.38 no.10
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• pp.1185-1191
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• 2014

Gas turbine blades that have complex geometry of the cooling holes and cooling passages are usually subjected to cyclic and sustained thermal loads due to changes in the operating characteristic in combined power plants; these results in non-uniform temperature and stress distributions according to time to gas turbine blades. Those operation conditions cause creep or thermo-mechanical fatigue damage and reduce the lifetime of gas turbine blades. Thus, an accurate analysis of the stresses caused by various loading conditions is required to ensure the integrity and to ensure an accurate life assessment of the components of a gas turbine. It is well known that computational analysis such as cross-linking process including CFD, heat transfer and stress analysis is used as an alternative to demonstration test. In this paper, temperatures and stresses of gas turbine blade were calculated with fluid-structural analysis integrating fluid-thermal-solid analysis methodologies by considering actual operation conditions. Based on analysis results, additionally, the total lifetime was obtained using creep and thermo-mechanical damage model.

• Journal of Korean Ophthalmic Optics Society
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• v.4 no.2
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• pp.129-133
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• 1999

For the myopia eyes of the people which are ametropia, the classified distribution has showed % for the simple myopic, 50% for the compound myopic astigmatism, 15% for the simple myopic astigmatism and 19% for the mixed astigmatism. The myopic ametropia for the both eyes has the distribution of 35% for -0.50D~-2.00Dptr, 54% for -2.00~6.00Dptr, and 11% for over -6.00Dptr. The classifying distribution for the age for the myopic ametropia was 54% for 15~20, 22% for 21~40, 14% for 41~60 and 10% for 61. The occupational distribution for the myopic ametropia has showed 61.5% for the student(Middle, High, College), 13.5% for the office worker, and 15% for the house wives as well as the small business. The hour affecting the refraction most for a day was after P.M. 7 which recorded 45% as the highest value. The reason is that the myopia degree decreases in the morning as the cornea flats and the situation is reversed in the afternoon so that there is a difference of Sph -0.50D and as getting darker the refraction degree of the light coming through the enlarged pupil refraction around the cornea is high. For the seasons the highest myopic degree has been recorded for 68% in the summer due to the shortage of nutrition and the climination inside the body by the exhaustion of sweat. In the blood types A and B are distributed closely as 34% and more active man with O has recorded higher myopic degree than woman. However woman showed higher accommodation power than man regardless the blood types. In the characteristic factors of myopic eye, the character feels fatigue easily has showed the distribution for 42% which is the highest and it could be classified largely by two the.

• Journal of Navigation and Port Research
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• v.30 no.6 s.112
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• pp.551-559
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• 2006

The purpose of this study was to find out morbidity rate and pattern of disease and affect of variables related disease and medical management of seafares'. The subjects this study were 1049 seafares' were took education in Korea Institute of Maritime and Fisheries Technology. This questionnaire was focused on finding the basic data for prevention of disease and promotion health for the seafares'. The collected data were analyzed by using descriptive statistics, Chi-square, cross tab, linear regression by SPSS 10.1 package. The result of this study are as follow. 1)The morbidity rate within recent 12 months was 69.0%. 2)there were significant differences qf occurred disease in age(p<0.05), income(p<0.01), career of ship on board(p<0.01), rank(p<.01), perceived health status(p<0.01), worry of health(p<0.01), fatigue symptoms(0.01), satisfy of job(p<0.05), rest time(p<0.05) 3) Considering disease unable to work more than 4 hour, the number of those who had oral disease 7.3%> tinea 6.6%> gastric ulcer 6.4, and musculoskeletal disease group were 20.9%, which revealed the highest rate oral disease 13.6%> skin disease> 12.4%, digestive disease> 12.1%. 4) As refer to medical management, The pain above 31days 35.7%, hospitalization and treatment below 7days were each 50.2%, 42.8%, medical service were doctor's office 27.9, which revealed the highest rate.

• Composites Research
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• v.26 no.5
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• pp.289-294
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• 2013

A thinner is used to improve the multi-walled carbon nano-tube (CNT) and carbon black (CB) dispersion in a polymer matrix and to make a soft electrode. The electrical and mechanical properties of the soft electrodes are investigated as functions of CNT, CB and thinner content. The optimal mixing condition for the electrode is thinner 80, CNT 3.5, CB 18 (phr) on the basis of matrix (KE-12). The specific resistance of that is 73 (${\Omega}{\cdot}cm$), and tensile strength, tensile modulus, and elongation of that is 0.45 MPa, 0.21 MPa, and 184%, respectively. Also, a simple structure of the actuator with an optimized electrode and elastomer is fabricated and its characteristic is evaluated. At the operating voltage 25 kV, the displacement of an elastomer KE-12 is 2.24 mm, and that of an elastomer KE-12 with thinner 50 (phr) is 4.05 mm. It shows a higher displacement compared to that of 3M 4910 which has similar modulus. The actuator made with elastomer and electrode of the same material (KE-12) may have advantages for fatigue life and application.

• International Journal of High-Rise Buildings
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• v.1 no.1
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• pp.37-51
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• 2012

New generation of tall and complex buildings systems are now introduced that are reflective of the latest development in materials, design, sustainability, construction, and IT technologies. While the complexity in design is being overcome by the availability and advances in structural analysis tools and readily advanced software, the design of these buildings are still reliant on minimum code requirements that yet to be validated in full scale. The involvement of the author in the design and construction planning of Burj Khalifa since its inception until its completion prompted the author to conceptually develop an extensive survey and real-time structural health monitoring program to validate all the fundamental assumptions mad for the design and construction planning of the tower. The Burj Khalifa Project is the tallest structure ever built by man; the tower is 828 meters tall and comprises of 162 floors above grade and 3 basement levels. Early integration of aerodynamic shaping and wind engineering played a major role in the architectural massing and design of this multi-use tower, where mitigating and taming the dynamic wind effects was one of the most important design criteria established at the onset of the project design. Understanding the structural and foundation system behaviors of the tower are the key fundamental drivers for the development and execution of a state-of-the-art survey and structural health monitoring (SHM) programs. Therefore, the focus of this paper is to discuss the execution of the survey and real-time structural health monitoring programs to confirm the structural behavioral response of the tower during construction stage and during its service life; the monitoring programs included 1) monitoring the tower's foundation system, 2) monitoring the foundation settlement, 3) measuring the strains of the tower vertical elements, 4) measuring the wall and column vertical shortening due to elastic, shrinkage and creep effects, 5) measuring the lateral displacement of the tower under its own gravity loads (including asymmetrical effects) resulting from immediate elastic and long term creep effects, 6) measuring the building lateral movements and dynamic characteristic in real time during construction, 7) measuring the building displacements, accelerations, dynamic characteristics, and structural behavior in real time under building permanent conditions, 8) and monitoring the Pinnacle dynamic behavior and fatigue characteristics. This extensive SHM program has resulted in extensive insight into the structural response of the tower, allowed control the construction process, allowed for the evaluation of the structural response in effective and immediate manner and it allowed for immediate correlation between the measured and the predicted behavior. The survey and SHM programs developed for Burj Khalifa will with no doubt pioneer the use of new survey techniques and the execution of new SHM program concepts as part of the fundamental design of building structures. Moreover, this survey and SHM programs will be benchmarked as a model for the development of future generation of SHM programs for all critical and essential facilities, however, but with much improved devices and technologies, which are now being considered by the author for another tall and complex building development, that is presently under construction.

• Journal of the Korea Concrete Institute
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• v.25 no.1
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• pp.63-72
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• 2013

HTB (hybrid truss bridge) steel truss webs instead of concrete webs in prestressed box girder bridges has been widely used in, because of its structural benefit such as relatively less self-weight and good aesthetics due to open web structure. Since the core technology of this bridge is the connection system between concrete slabs and steel truss members, several connection systems were proposed and experimentally evaluated. Also, the selected joint system was applied to the real bride design and construction. The researches were performed on the connection system, since it can affect the global behavior of this bridge such as flexural and fatigue behaviors as well as the local behavior around the connection region. The evaluation study showned that HTB applied to a curved bridge or a eccentric loading bridge, characteristic has a weak torsional capacity compared to an ordinary PSC box girder bridges due to the open structure of HTB. In this study, three box shaped hybrid truss specimens were made and the torsional test and evaluation for them were performed in order to find out the torsional behavior of HTB according to the connection system.

• Journal of the Institute of Electronics and Information Engineers
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• v.52 no.7
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• pp.135-142
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• 2015

Human-powered self-generating devices have been attractive with its operation characteristic independent from outer environment such as weather condition and wind speed. However, conventional self-generators have low electric power output due to their weakly-coupled electromagnetic structure. More importantly, rotary crank motion which is usually adopted by conventional self-generator to generate electricity requires specific skeletal muscles to maintain large torque circular motion and consequently, causes fatigue on those muscles before it can generate enough amount of electricity for any practical application. Without improvement in electric power output and usability, the human-powered self-generator could not be used in everyday life. This study aims to develop a human-powered self-generator which realized a strong electromagnetic coupling in a closed-loop tubular structure (hula-hoop shape) for easy and steady long-term driving as well as larger electric output. The performance and usability of the developed human-powered generator is verified through experimental comparison with a commercial one. Additionally, human workload which is a key element of a human-powered generator but not often considered elsewhere, is estimated based on metabolic energy expenditure measured respiratory gas analyzer. Further study will focus on output and portability enhancement, which can contribute to the continuous power supply of mobile equipments.

• Women's Health Nursing
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• v.5 no.1
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• pp.80-95
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• 1999

The purpose of this study was to investigate the characteristics of low birth-weight infants and their's mothers, and to identify the factors which influenced to delivery of L.B.W infants. The data derived from K. General Hospital and J. obs & gyn clinic in pusan from January, 1998 to August, 1998, which were from mothers of having B. W infants. The factors used for this study were characteristics of general, obstetrical, environmental aspects and physical and psychological life experiences during pregnancy. Analysis of data obtained were computerized statistically by using SPSS 7.5 WIN program. the data were analysed as number, frequency, percentage, t-test and ANOVA. The major results obtained of this study were as follows : 1) Gender that L.B.W infants were male in 47.2% and female in 52.8%, body weight of 2001~2500gm was above 8 in 68.5%, and below 5 in 1.8%. The L.B.W infants with complications were 7, which were 6.5%. The kinds of malformations were the Cleft palate & lip, Hyper-kalemia, Hypoglycemia, Meningocele, CHD, Down syndrome and each of them marked 0.9%. 2) In the general characteristics of pregnant women, the age group of 25~29 years was the most common as 46.3%. Over 35 years of age, elderly gravidas were in 7.5%. the height of 156~160cm was the most common as 52.8%. pregnant women of below 150cm height was in 3.7%. body weight of 51~55kg was the most common as 38%. pregnant women of below 45kg were in 19.4%. The women with smoking and drinking episodes during pregnancy were 1.9% and 25%. In the status of marriage, married women were in 95.4%, unmarried ones were in 1.9%, and unmarried couples were in 2.8%. Iin he obstetrical characteristics of pregnant women, pregnant women with gestational age under 37wks were in 45.4%, and the ones over 38wks were 54.6%. At the methods of delivery, normal spontaneous vaginal deliveries were in 51.9%, which were the most common, cesarian section deliveries were in 47.2%, and breech deliveries were in 0.9%. In the environmental characteristics of pregnant women, 40.8% of pregnant women lived in house or apartments with stairs, 23.1% of them lived in the high altitude. the pregnant women who ran a household without a helper were in 65.7%. In the pregnant women who had underwent life experiences of physical and psychological stress during pregnancy. life experiences of physical stresses were described as persistent fatigue due to lifestyle, traumatic experience, illness, move away with an effort, physical impact caused by discord. life experiments of psychological stresses were describeded as trouble with their husbands, discord with one's husband family, family problems, and conflicts due to environmental factors, etc. The number of the pregnant women who had complications during pregnancy was 32, which was 29.6% totally. Among them, pre-eclampsia was in 12.1% and the premature rupture of membrane in 7.4%. 3) In the analysis of the general, obstetrical, and circumstantial characteristics and L.B.W infants. There were statistical difference significantly between the gestational age of pregnant women(F=12.035, P=.000), and the status of marriage(F=3.207, P=.044), and maternal complication(t=2.344, P=.021) etc.