• Explosives and Blasting
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• 제30권2호
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• pp.29-42
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• 2012

Variables influencing the free face movement due to rock blasting include the physical and mechanical properties, in particular the discontinuity characteristics, explosive type, charge weight, burden, blast-hole spacing, delay time between blast-holes or rows, stemming conditions. These variables also affects the blast vibration, air blast and size of fragmentation. For the design of surface blasting, the priority is given to the safety of nearby buildings. Therefore, blast vibration has to be controlled by analyzing the free face movement at the surface blasting sites and also blasting operation needs to be optimized to improve the fragmentation size. High-speed digital image analysis enables the analyses of the initial movement of free face of rock, stemming optimality, fragment trajectory, face movement direction and velocity as well as the optimal detonator initiation system. Even though The high-speed image analysis technique has been widely used in foreign countries, its applications can hardly be found in Korea. This thesis aims at carrying out a fundamental study for optimizing the blast design and evaluation using the high-speed digital image analysis. A series of experimentation were performed at two large surface blasting sites with the rock type of shale and granite, respectively. Emulsion and ANFO were the explosives used for the study. Based on the digital images analysis, displacement and velocity of the free face were scrutinized along with the analysis fragment size distribution. In addition, AUTODYN, 2-D FEM model, was applied to simulate detonation pressure, detonation velocity, response time for the initiation of the free face movement and face movement shape. The result show that regardless of the rock type, due to the displacement and the movement velocity have the maximum near the center of charged section the free face becomes curved like a bow. Compared with ANFO, the cases with Emulsion result in larger detonation pressure and velocity and faster reaction for the displacement initiation.

• The monthly packaging world
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• 통권319호
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• pp.69-72
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• 2019

• Journal of the Korea Society of Computer and Information
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• 제17권11호
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• pp.33-38
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• 2012

An free-fall object is received only force of gravity. Movement that only accept gravity is free-fall movement, and a free-falling object is free falling body. In other words, free falling body is only freely falling objects under the influence of gravity, regardless of the initial state of objects movement. In this paper, we assume, ignoring the resistance of the air, and the free-fall acceleration by the height does not change within the range of the short distance in the vertical direction. Under these assumptions, we can know about time and maximum height to reach the peak point from jumping vertically upward direction, time and speed of the car return to the starting position, and time and speed when the car fall to the ground. It can be measured by jumping degree and risk of accident from car or motorcycle in telematics.

• Journal of Ocean Engineering and Technology
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• 제37권3호
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• pp.89-98
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• 2023

Analyzing the interactions of free surface waves caused by a submerged-body movement is important as a fundamental study of submerged-body motion. In this study, a two-dimensional mini-towing tank was used to tow an underwater body for analyzing the generation and propagation characteristics of free surface waves. The magnitude of the maximum wave height generated by the underwater body motion increased with the body velocity at shallow submerged depths but did not increase further when the generated wave steepness corresponded to a breaking wave condition. Long-period waves were generated in the forward direction as the body moved initially, and then short-period waves were measured when the body moved at a constant velocity. In numerical simulations based on potential flow, the fluid pressure changes caused by the submerged-body motion were implemented, and the maximum wave height was accurately predicted; however, the complex physical phenomena caused by fluid viscosity and wave breaking in the downstream direction were difficult to implement. This research provides a fundamental understanding of the changes in the free surface caused by a moving underwater body.

• The monthly packaging world
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• 통권319호
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• pp.73-75
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• 2019

• The Journal of Korean Physical Therapy
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• 제10권1호
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• pp.193-198
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• 1998

This study was introduce to Manual Therapy of Mulligan. The use of sustained natural apophyseal glides (SNAGS) and mobilisation with movement(MWM) for spine and peripheral joints has been developed by Mulligan. A mobilisation is applied parallel or right angles to restricted joint movement. If the applied mobilisation achieves immediate improvement in the functional movement and abolishes the pain the treatment involves sustaining the mobilisation while the patient performs the active movement repetitively. On reassessment of the joint function the movement should remain improved without the mobilisation. Theories as to why these techniques provide rapid improvement in pain-free range are proposed, and general principle of examination and treatment are outlined.

• Korean Institute of Interior Design Journal
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• 제8호
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• pp.16-22
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• 1996

In terms of modern design history, De Stijl movement had continued as one of influential groups by 1931, and it attempted to pursue universial reality that combined painting and architecture, seeking a new style based on Neo-Plasticism and succeeded the nineteen century's Art and Craft movement and Art Nouveau. Especially, the De Stijl movement provided 1920's rationalism with new space pattern and its ideas greatly affected the Bauhaus movement such as Walter Gropius or Mies van der Rohe. De Stijl's utopian idea that claimed on the conformity of art and life contributed modernism movement combined with scientific and rational view, and even now experts its lasting power with the concept of time and space free from simple cube in modern architecture and interior design. The tue meaning of the De Stijl movements is that is sis the basis of general ideas, and the change of modern architecture is based on this modern styled foundation. It may be the unchangeable fact like Russell Hitchocok says, "The architectural style and pattern which everyone admitts its importance has the value of living."

• Journal of Technologic Dentistry
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• 제25권1호
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• pp.111-118
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• 2003

I measured the movement range on the hinge articulator and the movement range in an oral. And then I studied to analyze the gap. I got wax records by the movement on the hinge articulator, the movement in an oral and the movement on the hand articulating. I measured the distance of the cusp tips that are close to the mesial direction and the distal direction, the buccal direction and the lingual direction then I compared gaps. As I saw results on data, I knew that the hinge articulator represented the range of mandibular movement restrictively. I could find the decisive contradiction that the sliding movement finished on the hinge articulator although it did not finish in an oral. If the sliding movement does not reappear exactly, it brings a fatal failure to the dental prosthesis. In addition it is impossible that the hinge articulator restores the movement in an oral because the lateral condyle inclination and the horizontal condyle inclination are fixed previously. Therefore dental prosthesisses were made by the hinge articulator, they will interfere with a mastication. I have obtained the following results; 1. The distance of sliding movement on the hinge articulator showed shorter than the distance of sliding movement in oral. This means the increase of cusp inclination of the dental prosthesis that was made on the hinge articulator. Therefore, when the lateral movement occurs in oral, there is a possibility to become the premature as the increase of cusp inclination. 2. The results that were impressed records in oral and impressed records on the hand articulating have many congruities. I think that the simple crown etc. that were made by the hand articulating method except the long span bridge and the free end case that can not measure the vertical dimension exactly can represent similarly the mandibular movement. 3. If we want to represent the mandibular movement similarly, we have to use the articulator that can adjust the horizontal condyle inclination and the lateral condyle inclination at least.

• Journal of the Korean Society of Industry Convergence
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• 제3권3호
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• pp.209-217
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• 2000

An attempt has been made to examine the highest liquid surface by means of measuring the movement of liquid free surface wave in the agitated vessel wall. Also, Relationship has been investigated between transition frequency, $N_z$ for behavior of liquid free surface and transition frequency for behavior of mass transfer coefficient in the agitated vessel wall. A surface wave is occured within agitated vessel, the highest height of wetted vessel wall, $h_w$ is coincided with the highest liquid surface, h. However the lowest height of wetted vessel, $h^*{_w}$ is not descended to lowest liquid free surface, $h^*$. The proposed model has been tested sucessfully for the behavior of liquid free surface.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• 제19권2호
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• pp.47-54
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• 2013

Background: Lateral epicondylitis is the most common complaint with complex etiological and pathophysiological factors on the lateral side of elbow. Taping techniques commonly used for lateral epicondylitis. The purpose of this study was to investigate the effects of mobilization with movement taping and diamond taping on the pain, grip strength and functional activity in patients with lateral epicondylitis Methods: Twenty patients with lateral epicondylitis (mobilization with movement taping group: n=10, diamond taping group: n=10) were recruited. They were evaluated pre-treatment, after 1weeks, and after 3weeks, using visual analog scale, pain free grip strength test, patient-rated tennis elbow evaluation. Results: Analysis showed statistcally significant improvement in all time in both groups. and The mean improvement in pre-1weeks visual analog scale was significantly greater in the Diamond taping group than that in the mobilization with movement taping group. and the mean improvement in pre-1weeks pain free grip strength test was significantly greater in the mobilization with movement taping than that in the diamond taping group. Conclusion: Taping technique to patients with lateral epicondylitis can help improve pain, grip strength, functional activity and initial taping technique can be selected depending on the patient's condition and the desired goal.