• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.35 no.9
• /
• pp.977-982
• /
• 2011

The horizontal force acting on a work roll was examined. This force results from the contact force between the work roll and backup roll in a backup-roll-drive 4-high cold-rolling mill. This horizontal force bends the work roll horizontally and therefore exerts reciprocal action on the roll-gap contour. An analytical model for predicting the horizontal force acting on a work roll, which generates a mean value in the steady state, was presented. The material used for the analysis was high-silicon steel (about 3% Si). A three-dimensional finite element (FE) model was also employed to investigate the non-steady-state behavior of the horizontal force. Results showed that the horizontal force varied with the off-center distance between the work roll and backup roll. In addition, the optimal off-center distance was determined to minimize the horizontal force.

• Journal of Korea Society of Industrial Information Systems
• /
• v.7 no.4
• /
• pp.37-45
• /
• 2002

In this study, to measure the density and moisture of compaction, it is designed to use the 2 neutron and 5 gamma-ray detectors. Also, it can be know that Co-60 gamma-ray and Cf-252 neutron source are more useful for this system, because discharge of radiation are better than other sources. They are more profitable to improve their accuracy. Especially, to remove the interference of their reciprocal action between neutron and gamma-ray detectors it is designed shield materials with lead between 2 neutron and 5 gamma-ray detectors each other. It is performed the optimal design to shield under the suggested values completely. Because this system will use portable, so decrease of their weight are so important. For this reason, it can be decrease their weight of 5.2[kg] with shield material between each detectors and it can be think mote easy to carry and use on the industrial Spot.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2009.10a
• /
• pp.635-638
• /
• 2009

The latest, Digital art is attempt new field's Art, that is utilize variously digital media image, sound, simulation, 3D holography. A large number of Digital Art is contact with the audiance in pavilion(limit place and limit period). However, It will be possible, If Digital Art can use place digital form media even there are indoor, outdoor, anywhere. This paper analyze reciprocal action for utilize Digital Art in indoor space design, and this paper study expression about indoor design base of interactive.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.29 no.4A
• /
• pp.299-305
• /
• 2009

In this study, in order to research the causes lead to fatigue crack in the coped stringer of a steel railway bridge, we take the steel railway bridge which actually occurs fatigue crack as a research object and manufacture the full size of crossbeam-stringer and floor system model to perform the experimental test. The results indicates that, the fatigue crack in the top of coped area of stringers is caused by the reciprocal action of the in plane stress in the tip of coped area of web by the negative moment occurred in the end of the stringers. While the fatigue crack in the bottom of coped area of stringers is due to the plane stress caused by the out-plane deformation relative to the bottom of coped area of web of the fixed end in the stringers.

• Journal of the Korea Concrete Institute
• /
• v.14 no.5
• /
• pp.689-697
• /
• 2002

The dynamic loads and load-point displacements of concrete three-point bend (TPB) specimens had been measured. The average crack velocities measured with strain gages were 0.16 ㎜/sec ∼ 66 m/sec. The fracture energy for crack extension was determined from the difference of the kinetic energy for the load-point velocity and the strain energy without permanent deformation from the measure external work. For all crack velocities, there were micro-cracking for 23 ㎜ crack extension, stable cracking for 61 ㎜ crack extension at the maximum strain energy, and then unstable cracking. The unstable crack extension was arrested at 80 ㎜ crack extension except the tests of 66 m/sec crack velocity. The tests less than 13 ㎜/sec crack velocity and faster than 1.9 m/sec showed static and dynamic fracture behaviors, respectively. In spite of much difference of the load and load-point displacement relations for the crack velocities, the crack velocities of dynamic tests did not affect on fracture energy rate during the stable crack extension due to the reciprocal action of kinetic force, crack extension and strain energy. During stable crack extension, the maximum fracture resistances of the dynamic tests was 147％ larger than that of the static tests.

• Journal of the Korean Chemical Society
• /
• v.43 no.5
• /
• pp.552-563
• /
• 1999

The study investigated and analyzed the middle school student's science textbook learning methods and strategies. The Preferred Mehtod of Study (PMOS) and a clinical interview method were utilized. Results indicate that there is a meaningful and significant positive correlation between the number of times students read a chapter of the science textbook and their science grade point. Students do not tend to alter learning strategies dependent upon the subject matter studied, but easily alter stratgies dependent upon the types of the test. Most students could not construct "organiztional tools" such as a summary, a chart, a talbe, or a figure when they study textbook, but might pursure and prefer only one method when they choose their learning strategise. Very few students (less than 1%) among those queried consciously try to connect between prior knowledge and new concepts in the textbook. Even though students choose the textbook for learning science in the beginning, they prefer to stick to reference and exercise materials. Therefore, detailed and direct studise of the student's learning methods and strategies, as well as research on cognitive psychology and motivational psychology, are necessary in order to develop a new textbook with student-based learning materials. By understanding the student's konwledge level through investigation of his or her learning style, an effective science education program can be realized. Finally, the role of the textbook as a tezching/learning material can be maximized by investigating and understanding the student's learning method and strategy with emphasis on reciprocal action between textbooks.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.29 no.1
• /
• pp.55-61
• /
• 1984

A Korean local maize line, MET, which has multi-ears and tillers has been proved as a potential source for silage production. However, no fundamental genetic nature for the line has been investigated. Therefore, this study was done to find genetic information on the multi-earing and -tillering habits of MET line. MET line and a hybrid. (Mo 17 ${\times}$ B68), with monoculm and single ear per plant were used for production of F$_1$(F$\_$1-12/ and F$\_$1-21/), F$\_$2-12/, F$\_$2-21/, BC$\_$1-12/ and BC$\_$1-21/ generations. From the comparison of reciprocal crosses, it was found that the tillering and earing habits of the MET line are controlled by cytoplasmic factors. The tiller and ear numbers, and barren ears were all characters associated with the MET cytoplasm. The cytoplasmic effect of MET on tiller and ear numb en was not evident in F$_1$ generation, probably because of suppressing effect of heterosis on appearance of tillers or ears. Genetic parameters for the gene action for both tiller and ear number also indicated a lack of mono- or digenic-chromosomal gene effects. The heritability (broad) was very low for both characters. Therefore, it is strongly concluded that the tillering and earing characters of MET line are due to cytoplasmic reasons.

• Journal of Korean Neurosurgical Society
• /
• v.47 no.1
• /
• pp.30-35
• /
• 2010

Objective: The purpose of this study is to explain the effect and reciprocal action among tumor necrosis factor (TNF) like weak inducer of apoptosis (TWEAK), fibroblast growth factor-inducible 14 (Fn14), and transforming growth factor-$\beta1$ (TGF-$\beta1$) on degeneration of human intervertebral disc (IVD). Methods: Human intervertebral disc tissues and cells were cultured with Dulbecco's Modified Eagle's Medium/Nutrient F-12 Ham (DMEM/F-12) media in $37^{\circ}C$, 5% $CO_2$ incubator. When IVD tissues were cultured with TWEAK, Fn14 that is an antagonistic receptor for TWEAK and TGF-$\beta1$, the level of sulfated glycosaminoglycan (sGAG) was estimated by dimethyl methyleneblue (DMMB) assay and sex determining region Y (SRY)-box 9 (Sox9) and versican messenger ribonucleic acid (mRNA) levels were estimated by reverse transcriptase polymerase chain reaction (RT-PCR). Results: When human IVD tissue was cultured for nine days, the sGAG content was elevated in proportion to culture duration. The sGAG was decreased significantly by TWEAK 100 ng/mL, however, Fn14 500 ng/mL did not change the sGAG production of IVD tissue. The Fn14 increased versican and Sox9 mRNA levels decreased with TWEAK in IVD tissue TGF-$\beta1$ 20 ng/mL elevated the sGAG concentration 40% more than control. The sGAG amount decreased with TWEAK was increased with Fn14 or TGF-$\beta1$ but the result was insignificant statistically. TGF-$\beta1$ increased the Sox9 mRNA expression to 180% compared to control group in IVD tissue. Sox9 and versican mRNA levels decreased by TWEAK were increased with TGF-$\beta1$ in primary cultured IVD cells, however, Fn14 did not show increasing effect on Sox9 and versican. Conclusion: This study suggests that TWEAK would act a role in intervertebral disc degeneration through decreasing sGAG and the mRNA level of versican and Sox9.

• Korean Journal of Child Education & Care
• /
• v.17 no.3
• /
• pp.29-48
• /
• 2017

The purpose of this study was to analyze how father's play beliefs affect play flow and peer play behavior of young children, particularly as mediated by the father's play participation. For this purpose, 4 to 5-year-old children attending child care centers or kindergartens and their fathers were selected to participate in this study. Data on father's play beliefs and play participation were collected from the fathers, and data on the young children's play flow and peer play behavior from their teachers. Based on the collected data, the significance of the mediation model using Hayes's (2013) PROCESS macro was tested. According to the results of these analyses, the significant relationships between father's play beliefs and young children's play flow, reciprocal action of play and interruption of peer play were found mediated by father's play participation. This finding implies that father's play beliefs and his play participation may affect directly and indirectly the children's play flow and peer play behavior, underscoring the importance of father's play beliefs. In addition, the study's indicate that it is desirable to positively reinforce father's play beliefs by influencing father's play participation, in light of the likely positive influence of father's play beliefs over young children's social and emotional development.

• Korean Journal of Construction Engineering and Management
• /
• v.7 no.5
• /
• pp.115-127
• /
• 2006

Although the Korean government have made a plan of housing market with supply and concentrated on the welfare of the people, there are still a lot of problem in housing market for lack of a long-term vision and consistent policy of the government. The plan of 115% of housing diffusion in 2012 is in progress after its acquisition of 100% in 2002, but there are no changes in the rental housing rate of 43% in 2003. In addition, there are getting worse circumstances in the instability of housing market and the low-income bracket, because of the Korean construction firms' bankruptcy with an increase of unsold hosing and a rapid increase of housing prices. The government have made the strategy of revitalizing the economy and regional development by means of a million public rental housing plan for the low-income bracket and welfare. This paper introduces the basic information of the subjective strategy establishment with the analysis of the reciprocal action of influence factors for public rental housing by system dynamics theory and the effect of public rental housing in housing supply market which has a long-term dynamic form.