• Journal of Korean Ophthalmic Optics Society
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• v.12 no.3
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• pp.105-110
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• 2007

To investigate the ametropia and refractive error of 222 ametropic eyes of the 111 high school students in Gwangju Metropolitan City, the visual acuity test was performed by the object and subject method. 85% of the eye types were positive for myopia, 14% for emmetropia, and 1% for hyperopia, respectively. 38% of the abnormal refraction eyes were positive for simple myopia, 4% for myopia simple astigmatism, 56% for myopia compound astigmatism, and 0% for simple hyperopia, 0% for hyperopia simple astigmatism, 2% for hyperopia compound astigmatism, 0% for mixed astigmatism, respectively. 92% of the axes fo astigmatism were for astigmatism with-the-rule, 6% for astigmatism against-the rule, 2% for astigmatism oblique, respectively. As for the astigmatic power, 0.50 < cylinder < 1.00D was 68%, 1.00 < cylinder < 2.00D was 25%, and anything over the 2.00 cylinder D was 7%. As for the equivalent spheric power of myopic abnormal refraction eyes, -0.50 < spheric equivalent < -2.00D was 26%, -2.00D < spheric equivalent < -6.00D was 55% and anything over the -6.00D was 19%. The rate of wearing glasses was 74%. It increases compared to 20 years ago. 91% of the eye test place was the optical shop, 9% the eye doctor hospital. 80% of the students need to change their optical lenses because spherical equivalent power was over 0.50D.

• Korean Journal of Environmental Agriculture
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• v.27 no.4
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• pp.337-342
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• 2008

The nitrogen (N) and phosphorus (P) balances in Korea during 1985-2006, which calculated according to the surface balance method of the PARCOM guidelines, continually increased with the lapse of year, and then might keep the highest levels with about $250kg\;N\;ha^{-1}$ and $50kg\;P\;ha^{-1}$ in 2006 among OECD countries. National phosphorus balance of the developed OECD countries (Belgium, Denmark, Germany, The Netherlands) in the livestock feeding industries has significantly decreased, due to limit livestock feeding density and nutrient application level by using strong legislation. However, Korean P balance was not apparent decrease, since the number of livestock feeding heads has been increasing, irrespective with the decrease of chemical fertilizer consumption. Manure P portion to the total P input amount of the above four OECD Countries in nutrient balance has continuously inclined to 60-70%. Therefore, the large portion of livestock manure might be used as nutrient source in agricultural side in these countries. In particular, manure P application levels of Belgium and The Netherlands, which have relatively high P balance and manure P portion to total P input dose, was estimated to be $31-33\;kg\;p\;ha^{-1}$ in 2004, and it was similar level with that of Korea in 2006. The manure P application levels for agricultural purpose has continuously decreased in these two OECD countries. In contrast, our manure P application rate continuously increased, and therefore we need the strong political countermeasure to control livestock feeding density at the resonable level.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.20 no.7
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• pp.1269-1276
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• 2016

Recently, natural disasters including earthquakes, tsunamis, floods, and snowstorms, in addition to disasters of human origin such as arson, and acts of terror, have caused numerous injuries and fatalities around the world. During such disasters, victims need to obtain information such as the exact location of the disaster and appropriate evacuation routes in order to relocate to safe areas. In this study, We propose the algorithm for Emergency Rescue Evacuation Support System(ERESS). In case a emergency disaster occurs, ERESS is possible to detect it quickly using through the movement of people. The mobile terminal analyzes behavior and location of indoor pedestrian. And it sends the result to the server. The server determines whether an emergency situation occurred or not based on the received transmission information. When an emergency situation occurs, the server will notify it to the mobile terminal. Then, indoor pedestrian conduct emergency evacuation using mobile terminal.

• The Journal of the Korea Contents Association
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• v.18 no.5
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• pp.280-291
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• 2018

Recently, various interactions have been actively conducted through sharing and expressing opinions among users in social networks. In this process, since malicious users and fault information spread misinformation, trust is reduced irrespective of their will. To solve this problem, studies have been conducted to determine the trust of a user through direct-connected users. In this paper, we propose a enhanced user indirect trust discrimination scheme considering the connection relation and influence of users. The proposed indirect trust computation scheme derives the user's area of interest through user interaction and reconstructs the existing network considering the user connection relationship. The final indirect trust is also detected by determining whether the user is a malicious user through the influence of the user. Through various performance evaluations, we show that the proposed scheme achieves better performance than the existing method.

• Tunnel and Underground Space
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• v.13 no.2
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• pp.125-137
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• 2003

Field measurements were carried out in this study to investigate the behavior of cut and cover tunnel such as the distribution and the magnitude of the earth pressure during back fill process. Three kinds of measuring instruments, such as the earth pressure load cell, the concrete strain gauge and the reinforcing bar meter of embedded type in concrete structure were installed and measured. Earth pressure load cells measured the outside forces acting on the tunnel lining with radial directions. Three load cells were installed at the crown, the right and the left shoulder of the tunnel, respectively. Three sets of reinforcing bar meter were installed in the double reinforcements of the tunnel lining and their locations were the same with the position of the earth pressure load cells. Concrete strain gauge was installed only one site of the upper compressive part at the tunnel crown. Based on the measurements, the deformation and the earth pressure acting on the tunnel lining were investigated with the back fill process. Considerations on the validity of the field measurements were paid.

• Korean Journal of Crystallography
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• v.1 no.2
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• pp.76-83
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• 1990

The structures of dehydrated fully Ca2+ _exchanged zeolite A (a: 12.2a3(2) A and of its iodine sorption complex (a=12.258(2) A) have been determined by single-crystal X-ray diffraction methods in the cubic space group. Pm3m at 21(1)℃.the structures were refined to final R(weighted) indices of 0.081 with 206 reflections and 0.084 with 173 reflections, respectively for which I>3 w (I). In each structure. six divalent cations are located on three different theefold axes associated with 6-ring oxygens. Dehydrated Ca2+_A sorbs ca. 6.0 diiodine molecules per unit cell at 80℃(vapor pressure of I: is ca. 14.3 Torr). Each iodine molecule makes a close approach. along its ahs to framework oxygen atom with I-I distance of 2.71(2) A, I-O distance of 3.32(3) k. and I-I-0=180℃. The result indicates that diiodine molecule forms charge transfer complex with framework oxygen.

• Journal of the Korean Society of Physical Medicine
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• v.7 no.3
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• pp.319-327
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• 2012

Purpose : This study aimed to identify the asymmetry observed in the rehabilitative ultrasound imaging of lateral abdominal muscle thickness and performance between the affected and unaffected side during the abdominal drawing-in maneuver (ADIM), an exercise used to facilitate activation of selectively TrA to stabilize the trunk prior to limb movement. Methods : The Participants were twenty one patients with post-stroke hemiplegia in this study. Ultrasound imaging was used to measure amount of changes in thickness of the external oblique (EO), internal oblique (IO), transversus abdominis (TrA). A Paired t-test was used to compare relaxed muscle thickness to contracted muscle thickness of all 3 muscles between the affected and unaffected sides. Results : The outcome measures included side to side differences of absolute thickness, contraction ratio among the lateral abdominal muscles. There was no significantly difference in between the affected and unaffected side at rest. But, there was a significantly difference in absolute muscle thickness between the affected and unaffected side of only TrA muscle. Also contraction ratio was a significantly difference between the affected and unaffected TrA muscle. Conclusion : These findings support the asymmetrical activation of TrA muscle during abdominal muscle contraction in patients with post-stroke hemiplegia. Further studies are warranted for confirming this outcome.

• Korean Journal of Family Social Work
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• no.57
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• pp.183-215
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• 2017

This study analyzes Korean childcare policy from a caring democracy perspective by using the normative policy analysis method. In the midst of emergent new social risks engendered by low fertility and aging population, feminist scholars proposed a transformative paradigm shift from economic growth to caring oriented development on a macro scale but researches on how this grand principle can be reflected into each policy have hardly been discussed. Thus, this study intends to contribute to such policy-driven discussion by analysing childcare policy on the basis of three normative values of freedom, equality and justice re-interpreted by caring democracy theory. Following are key findings. First, childcare policy does not guarantee public value and social solidarity due to the limitations of free choice from the perspective of freedom. Secondly, gender and class stratification has been worsened in a multiple and more complicated way by adding generational and racial dimensions to the existing gender inequality and vicious circulation of private care is observed from equality perspective. Thirdly, structural inequality aggravated injustice previously accumulated in the past rather than providing flat ground by adjustment.

• Tribology and Lubricants
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• v.40 no.1
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• pp.8-16
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• 2024

This study conducts numerical modeling and eigen-analysis of a rod-fastened rotor, which is mainly used in aircraft gas turbine engines in which multiple disks are in contact through curvic coupling. Nayak's theory is adopted to calculate surface parameters measured from the tooth profile of the curvic coupling gear. Surface parameters are important design parameters for predicting the stiffness between contact surfaces. Based on the calculated surface parameters, elastoplastic contact analysis is performed according to the interference between two surfaces based on the Greenwood-Williamson model. The equivalent bending stiffness is predicted based on the shape and elastoplastic contact stiffness of the curvic coupling. An equation of motion of the rod-fastened rotor, including the bending stiffness of the curvic coupling, is developed. Methods for applying the bending stiffness of a curvic coupling to the equation of motion and for modeling the equation of motion of a rotor that includes both inner and outer rotors are introduced. Rotordynamic analysis is performed through one-dimensional finite element analysis, and each element is modeled based on Timoshenko beam theory. Changes in bending stiffness and the resultant critical speed change in accordance with the rod fastening force are predicted, and the corresponding mode shapes are analyzed.

• Journal of Korean Ophthalmic Optics Society
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• v.13 no.1
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• pp.125-129
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• 2008

Purpose: To research the study of abnormal refraction eye on women population of university students in South - East Korea. Methods: Between March 2007 and October 2007, the refraction test of eye glasses wearer was evaluated on women population (367 students, aged 19~22 years) of university in living on Kyung-Nam and Pusan province. Data was analysed with T-test. Results: On the abnormal refraction status, Compound Myopic Astigmatism was 76.72%, simple myopia was 10.90%, mixed astigmatism was 6.27%, respectively. On the prevalence of myopic power, low was 59.57%, moderate was 24.93%, high was 15.49%, respectively. On the myopic equivalent power, the right eye had more increase to compare to left eye. but these was not a statically significant correlation (p<0.5) between the right and left eyes. On the anisometropia of spherical equivalents and cylinder power, most subjects was under 1.0 diopter. On the other hand, the type of astigmatic axis was with-the rule (70.79%), against -the rule (18.41%), and oblique (10.80%). Conclusions: This study identify that the refraction status of abnormal refraction eye on women population in university students in South-East Korea have been more increased prevalence the myopia and astigmatism.