• Journal of The Korean Association For Science Education
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• v.28 no.7
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• pp.697-712
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• 2008

The purpose of this study was to seek strengths and weaknesses from analyzing Korea and U.S. science textbooks in terms of general structural features, contents, cognitive levels of questions and the purpose of questions used in science textbooks. This provided insight into improvement of textbooks that can effectively assist teaching and learning. To investigate organization of unit in textbooks in-depth, the evolution unit was selected and scrutinized as one example. The results showed that the number of pages, activities, vocabulary words, and vocabulary lists are considerably different between Korean and the U.S. Commonly, U.S. textbooks were more laden with information and lacking in coherence than those of the Korean textbooks. The findings on the cognitive levels of questions showed that the majority of questions in both nations are concerned with knowledge. However, the difference between the two nations is great in the ratios of analysis, synthesis, and evaluation questions. Questions are concentrated in review section (45% of Korean and 60.6% of U.S.) in textbooks. It suggested that well-planned questions in a review section can provide the basic guidance for strength in a science classroom.

• The Korean Society of Law and Medicine
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• v.15 no.2
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• pp.63-89
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• 2014

In 1976, the Dalkon Shield-intrauterine device injured several thousand women in U.S.A. which caused the changes of medical deivce regulation. The Medical Device Regulation Act or Medical Device Amendments of 1976 (MDA) was introduce. As part of the process of regulating medical devices, the MDA divides medical devices into three categories. The class II, and III devices which have moderate harm or more can use the section 510 (k), premarket notification process if the manufacturer can establish that its device is "substantially equivalent" to a device that was marketed before 1976. In 21 U.S.C. ${\S}$ 360k(a), MDA introduced a provision which expressly preempts competing state laws or regulations. After that, the judicial debates had began over the proper interpretation and application of Section 360(k) In February 2008, the U.S. Supreme Court ruled in Riegel v. Medtronic that manufacturer approved by the Food and Drug Administration (FDA)'s pre-market approval process are preempted from liability, even when the devices have defective design or lack of labeling. But the Supreme Court ruled in Medtronic Inc. v. Lora Lohr that the manufactures which use the section 510 (k) process cannot be preempted and in Bausch v. Stryker Corp. that manufactures which violated the CGMP standard are also liable to the damage of patient at the state courts. In 2009, the Supreme Court ruled in Wyeth v. Levine that patients harmed by prescription drugs can claim damages in state courts. This may cause a double standard between prescription drugs and medical devices. FDA Preemption is the legal theory in the United States that exempts product manufacturers from tort claims regarding Food and Drug Administration approved products. FDA Preemption has been a highly contentious issue. In general, consumer groups are against it while the FDA and pharmaceutical manufacturers are in favor of it. This issues also influences the theory of product liability of U.S.A. Complete immunity preemption is an issue need to be more declared.

• Communications of the Korean Mathematical Society
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• v.12 no.2
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• pp.287-291
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• 1997

Assume $H_i : R_+ \times R_+ \to R_+ (i = 1, 2)$ are monotonically increasing (in both variables), homogeneous mapping for which $H_1(tu, tv) = t^p(H_1(u, v) (p > 0)$ and $H_2(u, v)^{t^q} (q \leq 1)$ hold for $t, u, v \geq 0$. Using an idea from the paper of Baker, Lawrence and Zorzitto [2], the superstability problems of the functional inequalities $\Vert f(x+y) - f(x)f(y) \Vert \leq H_i (\Vert x \Vert, \Vert y \Vert)$ shall be investigated.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.4
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• pp.2860-2867
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• 2015

Stable channel design is to determine the width, depth and slope for satisfying the condition that the upstream incoming sediment rate is equal to the sediment transport rate at the design channel. Therefore, the most sensitive variable when designing a stable channel is the selection of a sediment transport equation applied for the channel design. Especially if in the case of gravel beds the designer uses the equation developed by using the data of sand rivers, the calculation result of the stable channel section has large errors. In this study, the stable channel design has been applied to the gravel bed river using the previous stable channel design program with newly added the sediment transport equation for gravel beds; and the stable channel section considering design constraints has been produced by using the analytical method. As results, in the case of the application with the fixed width, the depth predicted by Ackers and White's equation was the shallowest and Meyer-Peter and $M\ddot{u}ller's$ equation was 0.8 m deeper than the current section of 2.4 m. In the case of the application with the fixed depth, the width predicted by Engelund and Hansen's equation was twice wider than the current section and by Meyer-Peter and $M\ddot{u}ller's$ equation was 20 m wider than the current section of 44 m.

• Journal of Korean Society of Disaster and Security
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• v.15 no.3
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• pp.67-77
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• 2022

In South Korea, U-type girder development was attempted as a means to increase the length of I-type girder, but due to the large self-weight according to the post-tension method, the application of rail bridges of 30m or less is typical. There are not many examples of application of pre-tension type girder. This study does not limit the post-tension method, but applies the pre-tension method to induce a reduction in self-weight and materials used due to the reduction of the cross-section. In addition, we intend to apply the on-site pre-tensioning method using the internal reaction arm of the U-type girder. The prestressed concrete U-type girder bridge is composed of a concrete deck slab and a composite section. Compared to the PSC I-type, which is an open cross-section because the cross section is closed, structural performance such as resistance and rigidity is improved, the safety of construction is increased during the manufacturing and erection stage, and the height ratio is reduced due to the reduction of its own weight. Therefore, it is possible to secure the aesthetic scenery and economical of the bridge. As a result, it is expected that efficient construction will be possible with high-quality factory-manufactured members and cast-in-place members. In this paper, the introduction of the pre-tension method on-site and the analytical performance verification of the anchoring block for tension are included.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.15 no.4
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• pp.73-82
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• 2016

Recently, automobile industries have been developing many structural automotive parts made of thin, high-strength steel strips to produce safer and more environmentally friendly cars. The roll forming process has been considered one of the most efficient processes in manufacturing high-strength steel parts because it is a high-speed process that forms sheets in increments. However, most automotive parts vary longitudinally in their cross-sections. Therefore, it is difficult to apply the roll forming process to automotive parts made of high-strength steel. A variable section roll forming process has been proposed in recent studies. The rotational axes of the forming rolls are fixed, and the forming rolls have three-dimensional shape. As such, the cross-section of the part varies linearly along its length, and the angle between the bend line and longitudinal axis is less than 1 degree. Thus, the rate of cross-sectional variation along the length is relatively small. In this study, the rate of cross-sectional change along the length of a forming roll has been increased. Moreover, the angle between the bend line and longitudinal axis has been increased up to 15 degrees. The variable sections of the forming rolls have been designed for high strength steel parts with a symmetric u-type cross-section that varies linearly and symmetrically along the longitudinal axis.

• Journal of the Korea institute for structural maintenance and inspection
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• v.12 no.4
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• pp.79-86
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• 2008

Four RC shear wall specimens with a/d of 2.2 are designed. And a flexural retrofitting is performed for one specimen by both enlarging wall section and adding additional vertical reinforcements. Also the effectivity of jaketting wall sides is evaluated for the two methods using only steel plate or welded wire mesh with enlargement of section. Cyclic loads are applied to the retrofitted specimens according to the loading history proposed by ACI under constant axial force. Test result showed that the strength and ductility of specimen were improved where the section was enlarged after the installation of additional vertical reinforcements. Confining the ends of wall by U shape W.W.F. with enlargement of section showed most excellent structural capacity regarding to the strength and ductility. Retrofitting by using steel plate was much effective not only to protect the abrupt decrease of strength after yield but also to improve the deformation capacity.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.21 no.2
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• pp.89-98
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• 1985

As a primary step in studying the effects of the netting porosity on the net-shape in the four-seam trawling net, a series of experiments were performed changing the porosity of each panel, with the simplified mo:iel of the bag net made of porous vinyl film and that ma:ie of net webbing. These models were suspended horizontally in circularly flowing water, with two pairs of susp~nding threais to four points of symetry at the border of the bag mouth in place of both wing nets. And then, the section shape of the bag mouth photographed and the tensions on both pairs of suspending threads were measured with two load cells in circularly flowing water. From the results, the auther estimated an experimental equation from the relationship between the porosity of each panel in the bag net and the section shape of the bag mouth, h/w=k (l-Pr_u/lPr_s)

• Korean Institute of Interior Design Journal
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• v.18 no.1
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• pp.99-107
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• 2009

In order to prepare future green hospital architecture authentication system, this study is a comparative year report to Korean, the United States, Japanese, British, Canadian and Australian green building authentication systems. Also, the United States and Australian Green hospital authentication systems were examined, and the authentication items of hospitals were compared with those of civil architecture. Though the examination and analysis, the portion of indoor environmental quality section commonly shows the average of 20.7 percent in all 6 countries. Especially, IAQ(Indoor Air Quality) among inside IEQ(Indoor Environment Quality) is overwhelmingly much treated in Korea, the U.S.A, Canada and Australia. In Japan, heat, light and sound are the important factors for authentication evaluation, while in the U.K light are more emphasized for the authentication. 'LEED for Healthcare' as a hospital evaluation authentication system subdivided currently most. The system includes the detailed and extensive evaluation items ranging from hospital management, traffic, emission, water resources utilization to integrated design and furnishing. These overseas systems should be carefully investigated, researched and analyzed for an appropriate improvement of domestic green hospital authentication system. Also the current evaluation method of IEQ section of Korean GBCC needs to be modified. That's why the method puts too much importance on IAQ in IEQ section.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.30 no.4
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• pp.300-306
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• 2019

Transmission cross section(TCS) is described analytically as $2G{\lambda}^2/4{\pi}$ irrespective of the aperture shapes for various transmission resonant apertures, such as small ridged circular or H-shaped, U-shaped, or Jerusalem cross-shaped apertures in an infinite thin conducting plane. The proposed expression is validated by comparison with the numerical results obtained from the method of moments(MOM). The TCS characteristics of the transmission resonant cavity structure in a thick conducting plane are also studied and the equivalence between the two small aperture structures is reported from the viewpoint of transmission efficiency.