• Journal of the Korean Society of Industry Convergence
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• v.26 no.6_3
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• pp.1223-1231
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• 2023

In the case of internal combustion engine vehicles, transmissions are essential for various reasons, such as vehicle starting and speed control. However, in the case of electric vehicles, unlike internal combustion engine vehicles, a transmission is not necessarily required. Of course, considering the efficiency of electric vehicles, a transmission is necessary, but installing the existing transmission as is has the opposite effect due to increased vehicle weight, so it has not been considered so far. In this paper, a non-contact reducer type using the Arago disc effect is proposed rather than a transmission using a conventional gear train, and the aim is to examine whether this can increase the driving efficiency of electric vehicles while minimizing weight. In addition, the effectiveness of the proposed reducer will be verified by manufacturing and testing it.

• Journal of Acupuncture Research
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• v.21 no.6
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• pp.177-186
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• 2004

Introduction : Recent studies Suggested that there is a strong correlation between acupuncture stimulation and its related cortical activation. Anther study showed that either positive or negative BOLD effects could be observed depending on anatomical structure in acupuncture stimulation. In ttis study, we investigated a new acupoint $KI_6$ (照海), which was known as motor-related acupoint and obtained an evidence that the stimulation of $KI_6$ resulted in either negative or positive BOLD response to stimulation. Methods & Results : 1. Subjects and paradigms : Two separate stimulation paradigms were performed on five healthy (aged 22-23 yrs) in this study. First, the paradigm of acupuncture stimulation was that the acupuncture needle was inserted in acupoints $KI_6$, which is located in lateral side of the foot and then continuously twisted(補瀉를 除外한 捻轉法) for 70 seconds for 10 cycles of activation. During rest period (70 seconds), the needle was completed removed from acupoint. Total 60 cycles were performed and 10 images were obtained per cycle. Second, nonacupoint was randomly selected and the same paradigm was performed as acupoint stimulation. The stimulation protocol comprised 10 cycles of alternating. activation and rest (10 images per cycle). Total 60 cycles were performed and each cycle take about 1.5 sec for motor task. Subjects take an at least 15 minutes break before starting anther paradigm. 2. fMRI mapping : Multi-slice functional images were obtained on a 1.5T Magnetom Vision MRI scanner (Simens Medical, Erlangen, Germany) equipped with high performance whole-body gradients. The BOLD T2 * - weighted images were acquired with acho planar imaging sequence (TR = 1.2 sec, TE = 60 msec, and flip angle = $90_{\circ}$). The other sequence parameter are : FOV = 210 mm, matrix=$64{\times}128$ or $64{\times}64$, slice number=10 and slice thickness = 5 or 8 mm. the anatomic images were obtained with Spin-echo T1-weighted images. The resulting images were then anaiyzed with STIMULATE (CMRR, U. of Minnesota) to generate functional maps using a student T-test (p < 0.005) and cluster analysis. Both positive and negative response were evaluated. Conclusions : We have observed the activation of the motor cortex by stimulating motor-related acupoint ($KI_6$). Among five subjects, negative BOLD response was shown in four and positive response in one. All subjects showed positive response to conventional finger flexion-extension task. To understand the detailed mechanisms of correlation between acupuncture stimulation and BOLD fMRI changes and two typs of response, further study strongly required.

• Journal of the Korea Convergence Society
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• v.12 no.10
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• pp.211-218
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• 2021

A recent spread of personal mobility devices such as electric kickboards has brought about a rapid increase in accident cases. Such vehicles are susceptible to falling accidents due to their low dynamic stability and lack of outer protection chassis. This paper presents the development of an automatic emergency braking system and a safe starting system as driving assistance devices for electric kickboards. The braking system employed artificial intelligence to detect nearby threaening objects. The starting system was developed to disable powder to the motor until when the driver's boarding is confirmed. This study is meaningful in that it proposes the convergence technology of advanced driver assistance systems specialized for personal mobility devices.

• Journal of Acupuncture Research
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• v.18 no.5
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• pp.60-69
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• 2001

Objective : Recent studies Suggested that there is a strong correlation between acupuncture stimulation and its related cortical activation. Anther study showed that either positive or negative BOLD effects could be observed depending on anatomical structure in acupuncture. Material and Methods : 1) Subjects and paradigms : Two separate stimulation paradigms were performed on five healthy (aged 22-23 yrs) in this study. First, the paradigm of acupuncture stimulation was that the acupuncture needle was inserted in acupoints KI6(照海), which is located in lateral side of the foot and then continuously twisted(補瀉를 除外한 捻轉法) for 70 seconds for 10 cycles of activation. During rest period (70 seconds), the needle was completed removed from acupoint. Total 60 cycles were performed and 10 images were obtained per cycle. Second, non-acupoint was randomly selected and the same paradigm was performed as acupoint stimulation. The stimulation protocol comprised 10 cycles of alternating activation and rest (10 images per cycle). Total 60 cycles were performed and each cycle take about 1.5 sec for motor task. Subjects take an at least 15 minutes break before starting anther paradigm. Conclusion : In this study, I investigated a new acupoint KI6(照海) which was known as motor - related acupoint and obtained an evidence that the stimulation of KI6(照海) resulted in negative BOLD response to stimulation.

• The Journal of Korean Physical Therapy
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• v.23 no.1
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• pp.53-58
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• 2011

Purpose: The purpose of this study was to determine the effect of direct functional magnetic stimulation (FMS) of affected spinal cord on motor recovery following spinal cord injury in rats. Methods: After a contusion injury at the spinal level T9 using an NYU Impactor, functional magnetic stimulation was delivered by a magnetic stimulator through a round prototype coil (7 cm in diameter). Stimulation parameters were set as follows: repetition rate = 50 Hz (stimulus intensity 100% = 0.18 T), stimulation time = 20 min. Functional magnetic stimulation was administered twice a day, 5 days per week for 8 weeks starting 4 days after spinal cord injury. Functional magnetic stimulationwas delivered directly to the affected spinal cord. Outcomes of locomotor performance were assessed by the Basso Beattie Bresnahan (BBB) locomotor rating scale and by an inclined plane test weekly for 8 weeks. Results: In the BBB test, hindlimb motor function in the Functional magnetic stimulation group improved significantly more compared to the control group at 3, 4, 6, 7, and 8 weeks (p<0.05). In the inclined plane test, the angle of the plane in the functional magnetic stimulation group increased significantly more compared to the control group at 4, 5, 7, and 8 weeks (p<0.05). Conclusion: Our results demonstrate that direct Functional magnetic stimulation of the lesional site may have beneficial effects on motor improvement after spinal cord injury.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.6
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• pp.703-709
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• 2017

Korea Utility Helicopter(KUH) is a project to replace the aging helicopter presently being operated by the military with a domestic helicopter. The auxiliary power unit is a device that supplies emergency power to the system by an alternator installed when the main generator fails and the start motor converts the electrical energy of the battery into mechanical rotational energy to rotate the auxiliary power unit engine. With continuing power and operation, defects of the starting motor were found and improvements were carried out to solve it. In the failure mode analysis, the causes of possible defects were classified into 5 categories. Analysis of the 5 factors revealed that the main cause of defects is mechanical wear, which was found to be related to spring pressure. 250 tests were conducted through the theoretically determined pressure and regression analysis was performed with 4 sampling.The results showed that pressure was related to wear rate. In conclusion, early wear and breakage due to wear can be controlled through spring force and test showed the prediction of wear and the validity of the result were confirmed.

• The Korean Journal of Pain
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• v.12 no.1
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• pp.16-20
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• 1999

Background: Tourniquet pain has important impacts on anesthesia. Tourniquet pain and accompanying cardiovascular changes are important factors that make patients in distress during anesthesia. As tourniquet pain may be modified by anesthesia, a study on the changes in the neural functions by tourniquet inflation in normal volunteers is important. Methods: Time-dependent changes in tourniquet pain, heart rate, phantom limb sensation, motor function, pain to pressure on upper extremity of 10 healthy and unpremedied volunteers were measured. Each parameter were measured every 5 minutes starting from 10 minutes before inflation to 15 minutes after deflation of tourniquet. Tourniquet was deflated when the subject felt unbearable pain (score 100 with visual analog scale). Results: Subjects manifested time-dependent pain responses to tourniquet inflation, characterized by increase in VAS, systolic and diastolic blood pressure. Mean duration of tourniquet inflation was 36.4 minutes, volunteers experienced motor paralysis at 27.6 minutes and sensory loss at 33.1 minutes. Pain to pressure decreased over time in both arms. The degree of decrease was greater in the arm on which tourniquet was applied than that in the non-applied arm. Phantom limb sensation occurred in 3 subjects. Conclusions: This study demonstrated dynamic changes in the neural functions during tourniquet inflation period. Tourniquet-induced pain and resultant hypertension occurred in all subjects. Appropriate anesthetic management is needed for the surgery using tourniquet.

• Journal of the Institute of Convergence Signal Processing
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• v.8 no.2
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• pp.124-129
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• 2007

Recently, the application of the linear machine for industrial field is remarkably increased, especially for the gantry machine, machine tool system and CNC. However a linear meter remains the vibrational characteristic itself therefore, In these application fields, high position control performance is essentially required in both the steady and the transient states. In this paper, the design method for a position control is proposed by using the two-degree-of freedom PID controller. This method has great features for the linear machine drives such as no over-shoot phenomena and single gain tuning strategy. By comparison with conventional PID controller, the improvement of performance of a linear motor control system using two degrees of freedom controller are discussed. Through the simulation results, the usefulness of the proposed algorithm is proved. With the simulation results, it was made clear that the introduction of two degrees of freedom controller designed by the proposed method not only improves the over shoot and starting characteristic of response but also removes the undesirable characteristic variation.

• BMB Reports
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• v.45 no.8
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• pp.427-432
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• 2012

Primary cilia, single hair-like appendage on the surface of the most mammalian cells, were once considered to be vestigial cellular organelles for a past century because of their tiny structure and unknown function. Although they lack ancestral motility function of cilia or flagella, they share common ground with multiciliated motile cilia and flagella on internal structure such as microtubule based nine outer doublets nucleated from the base of mother centrioles called basal body. Making cilia, ciliogenesis, in cells depends on the cell cycle stage due to reuse of centrioles for cell division forming mitotic spindle pole (M phase) and assembling cilia from basal body (starting G1 phase and maintaining most of interphase). Ciliary assembly required two conflicting processes such as assembly and disassembly and balance between these two processes determines the length of cilia. Both process required highly conserved transport system to supply needed substance to grow tip of cilia and bring ciliary turnover product back to the base of cilia using motor protein, kinesin and dynein, and transport protein complex, IFT particles. Disruption of ciliary structure or function causes multiple human disorder called ciliopathies affecting disease of diverse ciliated tissues ranging from eye, kidney, respiratory tract and brain. Recent explosion of research on the primary cilia and their involvement on animal development and disease attracts scientific interest on how extensively the function of cilia related to specific cell physiology and signaling pathway. In this review, I introduce general features of primary cilia and recent progress in understanding of the ciliary length control and signaling pathways transduced through primary cilia in vertebrates.

• Biomolecules & Therapeutics
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• v.28 no.6
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• pp.512-518
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• 2020

Stroke is a leading cause of long-term disability in ischemic survivors who are suffering from motor, cognitive, and memory impairment. Previously, we have reported suppressing LPA₅ activity with its specific antagonist can attenuate acute brain injuries after ischemic stroke. However, it is unclear whether suppressing LPA₅ activity can also attenuate chronic brain injuries after ischemic stroke. Here, we explored whether effects of LPA₅ antagonist, TCLPA5, could persist a longer time after brain ischemic stroke using a mouse model challenged with tMCAO. TCLPA5 was administered to mice every day for 3 days, starting from the time immediately after reperfusion. TCLPA5 administration improved neurological function up to 21 days after tMCAO challenge. It also reduced brain tissue loss and cell apoptosis in mice at 21 days after tMCAO challenge. Such long-term neuroprotection of TCLPA5 was associated with enhanced neurogenesis and angiogenesis in post-ischemic brain, along with upregulated expression levels of vascular endothelial growth factor. Collectively, results of the current study indicates that suppressing LPA₅ activity can provide long-term neuroprotection to mice with brain ischemic stroke.