• Journal of ILASS-Korea
• /
• v.16 no.4
• /
• pp.201-209
• /
• 2011

Optimum engine performance is obtained when the spray characteristics is well matched to the geometry of a combustion chamber. Among many parameters governing the combustion performance in internal combustion engine, fuel supply characteristics and atomization are important performance factors. Therefore, spray characteristics of high pressure multi-hole injector has been studied experimentally. An experimental test system has been made to operate high pressure injection system and to visualize spray behavior. Spray visualization has been performed to analyze spray formation, spray cone angle, bent angle and penetration length. Spray interaction with piston has been analyzed with various injector installation angle, injection pressure and ambient pressure. Test results show that penetration length is greatly influenced by the injection pressure. Penetration length is decreased as ambient pressure increased. Spray cone angle is increased as injection pressure and ambient pressure increased. However, bent angle is not influenced by the change of injection pressure and ambient pressure. Spray cone angle distribution map is plotted using the experimental data. Fuel movement around the spark-plug has been enforced as increasing injector installation angle.

• Korean Journal of Remote Sensing
• /
• v.30 no.1
• /
• pp.127-136
• /
• 2014

When the mouth of the Nakdong River, opens its floodgate, thousands of tons of litter should flown into the South Sea, moving towards nearby coast, thus causing serious social and economic damage. For this reason, in the present study, research was performed on one certain area in northeast coast of Geoje island, which is assumed as area damaged due to rainy season and typhoon in 2012, and research for trace of movement route was implemented by using buoy to identify characteristic of movement of floating debris caused from Nakdong River. Flows related to the movement of floating debris was also identified by analyzing ocean meteorological environment. As a result of the study, total 40 tons of litter composed of grasses and trees(or plants litter) were flown into Heungnam beach on 16th, Jul which is the rainy season. Plus, the location tracking buoy, which was dropped when the typhoon SANBA was coming, was passed by southern sea of Gadeok-do and was flown into Geoje beach 1 ~ 2 days after it was dropped. The wind direction was mostly northeasterly wind around the Geoje beach at the time the buoy and floating debris were flown into northeast coast and there was common sea surface currents which was flowing into the coast.

• Korean Institute of Interior Design Journal
• /
• v.20 no.2
• /
• pp.64-71
• /
• 2011

There are a method to analyze reactions or psychological condition and a method to observe visitor's behavioral reaction as methods to measure and evaluate humans' recognition behavior reaction of humans. The measure of the eye movement as a method to living body's reaction and psychological condition has an advantage to measure the information acceptance reaction of view recognition of the stimulus of view composition factors which has been used since a long time ago in other research areas, but almost not studies have been made on the exhibition views in museums. Therefore, on the premise of such recognition, this study aimed at obtaining various types of information through vision angles of visitor in exhibition space of an museum and judging space information, at measuring the condition of information acceptance through attention experiments and observation investigation of and finding out the disposition and characteristics so as to verify the relationship between the exhibition space and exhibition Method.

• Magazine of the Korean Society of Agricultural Engineers
• /
• v.44 no.2
• /
• pp.81-98
• /
• 2002

The condition of initial movement far the river bank protection using rip rap is a limit condition beyond which the lining is progressively destroyed as the separate elements are removed by the flow. In the case of the river bank protection using gabion mattress, however, after the initial movement the containment offered by the mesh remains. A new situation of equilibrium with a deformed river bank protection using gabion mattress is obtained, allowing it to withstand more severe conditions without compromising the resistance and without further deformation. Shield's coefficient for the river bank protection using gabion mattress is twice the value of that fur river bank protection using rip rap. This means that with the same hydraulic behavior conditions, the average dimension of the rocks to be used in the river bank protection using gabion mattress is half that of river bank protection using rip rap rock. When the same size rocks are used the allowable velocity for the river bank protection using gabion mattress is more than twice, even as much as 3 or 4 times that for river bank protection using rip rap.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.12 no.5
• /
• pp.843-848
• /
• 2008

Most of face detection technique uses information from the face of the movement. The traditional face detection method is to use difference picture method ate used to detect movement. However, most do not consider this mathematical approach using real-time or real-time implementation of the algorithm is complicated, not easy. This paper, the first to detect real-time facial image is converted YCbCr and RGB video input. Next, you convert the difference between video images of two adjacent to obtain and then to conduct Glassfire Labeling. Labeling value compared to the threshold behavior Area recognizes and converts video extracts. Actions to convert video to conduct face detection, and detection of facial characteristics required for the extraction and use of AdaBoost algorithm.

• International Journal of Naval Architecture and Ocean Engineering
• /
• v.6 no.1
• /
• pp.87-97
• /
• 2014

In this study, the model tests were conducted on the short piles installed in sands under a horizontal pullout load to investigate their behavior characteristics. From the horizontal loading tests where dimensions of the pile diameter and length, and loading point were varied, the horizontal pullout resistance and the rotational and translational movement pattern of the pile were investigated. As a result, the horizontal pullout resistance of the pile embedded in sands was dependent on the pile length, diameter, loading point, etc. The ultimate horizontal pullout load tended to increase as the loading point (h/L) moved to the bottom from the top of the pile, regardless of the ratio between the pile length and diameter (L/D), reached the maximum value at the point of h/L = 0.75, and decreased afterwards. When the horizontal pullout load acted on the upper part above the middle of the pile, the pile rotated clockwise and moved to the pullout direction, and the pivot point of the pile was located at 150-360mm depth below the ground surface. On the other hand, when the horizontal pullout load acted on the lower part of the pile, the pile rotated counterclockwise and travelled horizontally, and the rotational angle was very small.

• Structural Engineering and Mechanics
• /
• v.72 no.2
• /
• pp.191-201
• /
• 2019

Finite element analysis is one of the most used tools for studying femoral neck fracture. Nerveless, consensus concerning either the choice of material characteristics, damage law and /or geometric models (linear on nonlinear) remains unreached. In this work, we propose a numerical quasi-brittle damage model to describe the behavior of the proximal femur associated with two methods to evaluate the Young modulus. Eight proximal femur finite elements models were constructed from CT scan data (4 donors: 3 women; 1 man). The numerical computations showed a good agreement between the numerical curves (load - displacement) and the experimental ones. A very encouraging result is obtained when a comparison is made between the computed fracture loads and the experimental ones ($R^2=0.825$, Relative error =6.49%). All specific numerical computation provided very fair qualitative matches with the fracture patterns for the sideway fall simulation. Finally, the comparative study based on 32 simulations adopting linear and nonlinear meshing led to the conclusion that the quantitatively results are improved when a nonlinear mesh is used.

• Korean Journal of Applied Biomechanics
• /
• v.17 no.1
• /
• pp.121-127
• /
• 2007

Muscle force produced by muscle fibers is transmitted to bones via tendinous structures(aponeuroses and tendon), resulting in joint(s) movement. As force-transmitting elements, mechanical behavior of aponeuroses and tendon are closely related with the function of muscle-tendon complex. The purpose of this study was to determine strain characteristics of aponeuroses for in-vivo human soleus muscle during submaximal voluntary contractions using an advanced medical imaging technique, velocity-encoded phase-contrast magnetic resonance imaging (VE-PC MRI). VE-PC MRI of the soleus muscle-tendon complex was acquired during submaximal isometric plantarflexion contraction-relaxation cycle (n = 7), using 3.0T Trio MRI scanner(Siemens AG, Malvern, MA). From the VE-PC MRI containing the tissue velocity in superior-inferior direction, twenty regions of interest(20 ROI; 10 on the anterior aponeurosis and 10 on the posterior aponeurosis) were tracked. During the isometric plantarflexion contraction-relaxation cycle, velocity and displacement profiles were different between the anterior and posterior aponeuroses, indicating heterogeneous strain behavior along the length of the leg. The anterior aponeurosis elongated while the posterior aponeurosis shortened during the initial phase of the contraction. Moreover, strain behavior of the posterior aponeurosis was different from that of the Achilles tendon. Possible explanation for the observed variations in strain behavior of aponeuroses was investigated with morphological assessment of the soleus muscle and it was found that the intramuscular tendinous structures significantly vary among subjects. In conclusion, the heterogeneous mechanical behavior of the soleus aponeuroses and the Achilles tendon suggests that the complexity of skeletal muscle-tendon complex should be taken into consideration when modeling the complex for better understanding of its functions.

• Journal of the Korean GEO-environmental Society
• /
• v.11 no.12
• /
• pp.27-35
• /
• 2010

The structures built under the groundwater level are affected by the buoyancy force, which is hydrostatic pressure in the up direction. Recently, buoyancy-resistant anchor method has been applied in many cases of the construction of the important structure of large size, which is built under the groundwater level so that it takes high uplift pressure. Even if the construction cost of the method is very high, it surely increases the safety rate. However, the diagnosis of the performance of the buoyancy-resistant permanent anchor and the investigation of resistance mechanism are still insufficient. Especially, the long-term behavior of the anchor has not been studied well due to the difficulty in observation procedure. The contribution of this paper is the establishment of reasonable design methodology. We have measured anchor axial forces for 10 years after the construction, by using an automated measurement and a manual measurement by establishing a load cell in anchor head. Through the data collected from the measurements, we analyze the construction-step behavior of the anchor according to the self-weight variation of the building and the long-term behavior (i.e. movement within 10 years after the construction) of the anchor according to the passage of time.

• Journal of Digital Convergence
• /
• v.16 no.4
• /
• pp.371-378
• /
• 2018

The purpose of this study is to investigate the effect of family relations on facility adaptation of the elderly. In January and February of 2018, a questionnaire survey was conducted on 5 ~ 6 elderly residents of each long-term care facility, and finally 353 data were used for analysis. The main results of the study were as follows: First, the adaptation level of the elderly was high. As for 'maladjustment of group behavior' and 'movement shock', the level of maladjustment is low as 2 points, and adaptation dimension such as 'accept of new residence' and 'making friend' is above the middle level. Second, the influence of family variables was more influential than the demographic characteristics of the elderly and the influence of the facility-related variables. Among them, the closeness with family is the most influential. Therefore, it is suggested that the elderly need active support and efforts to maintain the intimacy with the family from the entrance to the facility and the time after the entrance.