• Transactions of the Korean Society of Automotive Engineers
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• v.15 no.2
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• pp.135-142
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• 2007

MADYMO human model with the detail neck was used to investigate the reaction force of neck and neck injury from rear impact directions. In the validation simulation, head acceleration, thorax acceleration and the global kinematics of the head and neck were correlated well with experimental data. Acceleration data from three 15 km/h low speed car rear impact pendulum tests(rear-end, offset, oblique) were used to simulate the model. In the simulation results, the reaction force on the facet joint and discs in the oblique rear impact were higher than rear-end, offset rear impacts. Further research is still needed in order to neck injury analysis about different crash parameters.

• Transactions of the Korean Society of Automotive Engineers
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• v.18 no.1
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• pp.51-57
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• 2010

In recent years, a large number of study for rear impact has been conducted and as a result of study, researchers proposed the neck injury criteria and test procedures. But many questions, related to injury criteria and dummy biomechanical levels, remain unresolved. In recently reports, rear impact motions of BioRIDIIg is not humanlike but better than other dummy(HybridIII, RID3d). So, in this paper, 4 times sled test would be done to find the substitutable neck injury criteria in BioRIDIIg. To review corelation trend with neck injury critera and head-neck movement, we compared with recently announced neck injury criteria(NIC, Nkm, T1 ect.) and head-neck X-direction movement in BioRIDIIg. Finally, we find the head-neck X-direction movement on head C.G to T1 point may be considerable as the additional neck injury criteria.

• Journal of the Korean Society for Precision Engineering
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• v.32 no.11
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• pp.929-935
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• 2015

The long neck flange is used to connect piping arrangements where the lap joint is applied. Generally, the component can be manufactured by welding, but this method is both time and cost intensive. Embrittlement at the heat affected zones was also considered. A spinning method developed to improve the manufacturing process and solve the problems of welding. The flange area of the long neck flange can be formed by changing the direction of the metal flow, from axial to radial, while maintaining pressure by using an outer mold and a lap roller. A modified process was additionally developed using a round roller rather than the outer mold. In this modification, the round roller can form the shape of all sizes of long neck flange. Using these flexible methodologies, the cost to prepare outer molds and the time to install and remove the molds can be significantly reduced.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.41 no.1
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• pp.1-6
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• 2017

Ballistic impact on a soldier wearing a helmet can induce fatal injury, even if the helmet is not penetrated. Although studies on this type of injury have been performed, most of them have used an analytical model focused on head injury only. The injury of the neck muscles and cervical vertebrae by non-penetrating ballistic impact affects the survivability of soldiers, despite not inflicting fatal injury to the human body. Therefore, an analytical model of the head and neck muscles are necessary. In this study, an analysis of human body injury using the previously developed head model, as well as a cervical model with muscles, was performed. For the quantitative prediction of injury, the stress, strain, and HIC were compared. The results from the model including the cervical system indicated a lower extent of injury than the results from the model excluding them. The results of head injury were compared with other references for reliability.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.2
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• pp.291-299
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• 2002

This paper characterizes hi-directionally oscillating flow in planar microdiffusers in order to evaluate the frequency-dependent flow rectification performance of the microdiffusers. In the theoretical study, we analyze a hi-directionally oscillating flow in the planar microdiffuser. In the experimental study, we fabricate two different microdiffuser prototypes, having different neck widths of 100 ㎛ (D100) and 300 ㎛(D300), respectively. The experimental net flow rates are measured as 116.6 $\mu$ι/min. and 344.4 $\mu$ι/min. for D100 and D300, respectively. The experimental flow rate of D300 decreases at the oscillating flow frequencies higher than 90Hz, at which the net boundary layer thickness is reduced to the microdiffuser neck width. It is experimentally verified that the flow rectification performance and the net flow rate of the microdiffusers tend to decrease when the boundary layer thickness is smaller than the diffuser neck width.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.35 no.11
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• pp.1139-1145
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• 2011

An automated anastomotic ring-pin system consisting of both the anastomotic ring-pin system and the coupler device has eliminated the drawbacks of the suture method. High density polyethylene (HDPE), a material with outstanding biocompatibility and injection molding capability, was used in the ring. SUS316 stainless steel, Ti-6Al-4Nb, Ti-6Al-4V, and unalloyed titanium were used in FEM simulations of the micropin. The authors categorized the microvascular anastomotic ring micropins into short neck (SN) and long neck (LN) groups in order to evaluate the effect of the micropin's fillet radius and neck length on the von Mises stress. The micropins were further divided into those with and without fillet. On the basis of the fillet radius rate (FRR), which represents the rate of change in the von Mises stress with respect to the availability and shape of the fillet, and the neck length rate (NLR), which represents the rate of change in the von Mises stress with respect to changes in the length of the neck within the fillet shape, it can be concluded that the SN-3 neck design is the most stable.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.5
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• pp.723-731
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• 2013

This study provides a comparative analysis of the effects of pre-slaughter penetrative and non-penetrative stunning and post-slaughter stunning on meat quality attributes in longissimus lumborum (LL) and semitendinosus (ST) muscles in heifers. Ten animals were assigned to each of four treatment groups: i) animals were subjected to conventional Halal slaughter (a clean incision through the structures at the front of the upper neck - the trachea, oesophagus, carotid arteries and jugular veins) and post-cut penetrating mechanical stun within 10 to 20 s of the neck cut (Unstunned; US); ii) high power non-penetrating mechanical stunning followed by the neck cut (HPNP); iii) low power non-penetrating mechanical stunning followed by the neck cut (LPNP); and iv) penetrative stunning using a captive bolt pistol followed by the neck cut (P). For each carcass, muscle samples were removed within 45 min of slaughter, portioned and analysed for pH, cooking loss, water holding capacity (WHC), tenderness (WBS), lipid oxidation (TBARS) and color, over a two week storage period. Stunning did not affect pH and cooking loss. Significant differences in water holding capacity, tenderness, lipid oxidation and color were present at different storage time points. HPNP stunning resulted in lower WHC and color values, particularly lightness ($L^*$), higher TBARS values and peak force values compared with those stunned using LPNP, P and US. These adverse effects on quality were mostly encountered in the ST muscle. In conclusion, the meat quality achieved using P, LPNP and US treatments was comparable, and no treatment stood out as considerably better than another.

• Transactions of the Korean Society of Automotive Engineers
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• v.21 no.4
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• pp.54-61
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• 2013

Although typically classified as AIS 1, whiplash injuries continue to represent a substantial social problem with associated costs estimated at over $1 billion annually. The primary objective of this study was to determine the effects of seat positions(seatback angle, headrest height) on risk for whiplash injury in very low speed(${\Delta}V$=4~10km/h) rear-end impact. To accomplish this, rear impact seat carriage tests and simulations were conducted using the BioRID-II dummy seated in a mass production seat, which allowed for the adjustment of seatback angle and headrest height. Neck injury criteria(NIC, Nkm) were then compared for different ${\Delta}V$ and seat positions.

• Physical Therapy Korea
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• v.22 no.3
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• pp.50-60
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• 2015

The purpose of this study was to apply the joint mobilization technique to the level of segments with pain and to the level of segments with hypomobility respectively and compare the immediate effects of the joint mobilization technique on the pain, the active cervical range of motion (ROM), and treatment satisfaction of patients with acute mechanical neck pain. After the baseline assessment, forty-two patients were randomized into two groups: a painful group ($n_1=21$) that received joint mobilization at the most painful cervical spine level and a hypomobile group ($n_2=21$) that received joint mobilization at the most hypomobile cervical level. The patients received an intervention that applied unilateral posterior-anterior gliding for 5 minutes and two repetitions of 10 times of active extension motion with distraction. In the Wilcoxon signed-rank test, the painful group and the hypomobile group were improved significantly in all pain variables (p<.001), while the painful group was improved significantly in the active cervical flexion (p<.001), extension (p<.001), left side-bending (p<.01), right side-bending (p=.001), left rotation (p<.001), and right rotation (p<.001). The hypomobile group was significantly improved in active cervical flexion (p=.001), extension (p<.001), left side-bending (p<.05), right side-bending (p=.001), left rotation (p=.001), and right rotation (p<.01) after intervention. In the Mann-Whitney U test, there was no significant difference in any of the dependent variables after the intervention between the two groups, but the painful group was slightly superior to the hypomobile group in all variables except for the right lateral flexion ROM and treatment satisfaction. These outcomes suggest that the cervical joint mobilization may be applied to either the level of painful segments or the hypomobile segments for the treatment of patients with acute mechanical neck pain.

• Structural Engineering and Mechanics
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• v.74 no.1
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• pp.19-32
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• 2020

Metallic energy-dissipation dampers are widely used in structures. They are comprised of an added damping and stiffness (ADAS) device with many parallel, diamond-shaped hole plates, the neck width of which is an important parameter. However, no studies have analyzed the neck width's influence on the ADAS device's performance. This study aims to better understand that influence by conducting a pseudo-static test on ADAS, with three different neck widths, and performing finite element analysis (FEA) models. Based on the FEA results and mechanical theory, a design neck width range was proposed. The results showed that when the neck width was within the specified range, the diamond-shaped hole plate achieved an ideal yield state with minimal stress concentration, where the ADAS had an optimal energy dissipation performance and the brittle shear fracture on the neck was avoided. The theoretical values of the ADAS yield loads were in good agreement with the test values. While the theoretical value of the elastic stiffness was lower than the test value, the discrepancy could be reduced with the proposed modified coefficient.