• Title/Summary/Keyword: external shock

Search Result 201, Processing Time 0.027 seconds

External Iliac Artery Injury Caused by Abdominal Stab Wound: A Case Report (복부 자상에 의한 외장골 동맥 손상에 대한 치험 1례)

  • Lee, Sang Bong;Kim, Jae Hun;Park, Chan Ik;Yeo, Kwang Hee
    • Journal of Trauma and Injury
    • /
    • v.28 no.3
    • /
    • pp.215-218
    • /
    • 2015
  • Traumatic iliac vessel injuries constitute approximately 25% of all abdominal vascular injuries. Hospital mortality has been reported at 25~60% and is a result of uncontrolled hemorrhage and hypovolemic shock caused by extensive blood loss. We report the case of a 25-year-old female patient who experienced an external iliac artery injury caused by abdominal minimal stab wound. Traumatic iliac vessel injuries are life-threatening complication of abdominal or pelvic injuries and prompt diagnosis and accurate treatment are important.

  • PDF

Variable Stiffness Series Elastic Actuator Design for Active Suspension (능동형 현가장치를 위한 가변 강성 직렬 탄성 액추에이터 설계)

  • Bang, Jinuk;Choi, Minsik;Lee, Donghyung;Park, Jungho;Park, Eunjae;Lee, Geunil;Lee, Jangmyung
    • The Journal of Korea Robotics Society
    • /
    • v.14 no.2
    • /
    • pp.131-138
    • /
    • 2019
  • In this study, we developed an FSEA(Force-sensing Series Elastic Actuator) composed of a spring and an actuator has been developed to compensate for external disturbance forced. The FSEA has a simple structure in which the spring and the actuator are connected in series, and the external force can be easily measured through the displacement of the spring. And the characteristic of the spring absorbs the shock to the small disturbance and increases the sense of stability. It is designed and constructed to control the stiffness of such springs more flexibly according to the situation. The conventional FSEA uses a fixed stiffness spring and the actuator is not compensated properly when it receives large or small external force. Through this experiment, it is confirmed that FSEA compensates the external force through the proposed algorithm that the variable stiffness compensates well for large and small external forces.

Development of Ball Type Separation Bolt (Ball Type 분리볼트 개발)

  • Kim, Dong-Jin;Kang, Won-Kyu;Lee, Yeung-Cho
    • Proceedings of the Korean Society of Propulsion Engineers Conference
    • /
    • 2006.11a
    • /
    • pp.243-246
    • /
    • 2006
  • Most of the guided weapons have been kept and transferred at the launching tube and fired in case of necessity in these day. Launching tube is a kind of case to protect the guided weapons from external environments and conducted as a guide when they are fired. When we attached the guided weapons to launching tube we usually has used explosive bolt. Explosive bolts have been used explosives when they had to be separated. But when they are separated there are some bad effects; a flame, fragments and pyre-shock. Because of these bad effects there are many restriction to use bolt as joining devices to precision guided weapons. To solve these problems we invented ball type bolt. Unlike explosive bolt, ball type bolt is separated without a flame, fragments and pyre-shock. And it also has a good mechanical properties as much as those of explosive bolt.

  • PDF

Development of Ball Type Separation Bolt (Ball Type 분리볼트 개발)

  • Lee, Yeung-Jo
    • Proceedings of the Korean Society of Propulsion Engineers Conference
    • /
    • 2008.05a
    • /
    • pp.179-182
    • /
    • 2008
  • Most of the guided weapons have been kept and transferred at the launching tube and fired in case of necessity in these day. Launching tube is a kind of case to protect the guided weapons from external environments and conducted as a guide when they are fired. When we attached the guided weapons to launching tube we usually has used explosive bolt. Explosive bolts have been used explosives when they had to be separated. But when they are separated there are some bad effects; a flame, fragments and pyro-shock. Because of these bad effects there are many restriction to use bolt as joining devices to precision guided weapons. To solve these problems we invented ball type bolt. Unlike explosive bolt, ball type bolt is separated without a flame, fragments and pyro-shock. And it also has a good mechanical properties as much as those of explosive bolt.

  • PDF

Protector Design and Shock Analysis for a Launch-Reconnaissance Robot (발사형 정찰로봇을 위한 보호체 설계 및 충격해석)

  • Kang, Bong-Soo;Park, Moon-Sik
    • Transactions of the Korean Society of Mechanical Engineers A
    • /
    • v.35 no.8
    • /
    • pp.971-976
    • /
    • 2011
  • This paper presents the design concepts of a protector for a launch-reconnaissance robot that is to be deployed for data-collection in hazardous regions. The protector protects the reconnaissance robot inside from shock induced during the process of launch, flight, and landing. Since the outer shells of the protector are automatically opened wide by the unlocking mechanism during the landing stage, the reconnaissance robot can easily exit the protector and move around to carry out its mission. We carefully simulated a finite-element model of the protector with the robot and compared the results with the actual dynamic behavior of the system. Shock- response tests using a droptable showed that the proposed protector filled with silicon material successfully attenuated external shock.

An Experimental Study on the Improvement of City Gas Buried Double Piping Integrity (도시가스 매설이중배관 건전성 향상에 관한 실험적 연구)

  • Lim, Hyung-Duk
    • Journal of the Korean Society of Industry Convergence
    • /
    • v.23 no.5
    • /
    • pp.757-763
    • /
    • 2020
  • City gas buried pipes are managed by corrosion protection to prevent corrosion. In the case of the press-in section, the double pipe and the main pipe may cause corrosion under the influence of stray current, which can shorten the life of the pipes. In addition, if the insulator is filled in the press-in section, the press-in section itself is a single structure, and can be directly affected by external impact, and when the surrounding ground subsidence occurs, the stress may be concentrated, resulting in serious consequences. In this study, a serration-type shock absorber in the form of a sliding support was proposed as a new buried double piping construction method using EPS. The serration-type shock absorber can contribute to the improvement of the integrity of the buried double piping, as it can utilize the gas piping's own ductility and stress distribution characteristics with proper anti-corrosion management and shock-absorbing material properties by preventing contact inside the buried double pipe. However, for application to ground piping, there remains a task to supplement the vulnerability against fire due to the characteristics of EPS materials.

Experimental Investigations Into Low Current Steady State Arcs In A Dual-Airflow Model Interrupter

  • Shin, Young-June;Cho, Yun-Ok;Kim, Jin-Gi;Lee, Jeong-Rim
    • Proceedings of the KIEE Conference
    • /
    • 1992.07b
    • /
    • pp.961-965
    • /
    • 1992
  • It is well-known that shock waves frequently occur inside the nozzle of the interrupter, and that they play important roles in the arc interruption. A model interrupter with two-dimensional dual-airflow nozzles was used for this experiment. The arc was ignited with 1.4 mil copper wire stretched between the electrodes which were spaced out 56 mm. The arc current of 60 to 230 A was achieved by adjusting the external resistance from 5.5 to 1.6 ohms. The arc tests have been conducted for investigating the air arc characteristics, and the effects of shock waves and nozzle pressure ratios on the arc voltage, the arc resistance, the arc power, and average electric field. The results of these tests have been analyzed to provide insights into the arc characteristics for gas circuit breakers. The average electric field is represented by the function of the arc current to show the negative E-I characteristic explicitly. The effects of shock waves and nozzle pressure ratios are shown to be significant for a circuit breaker performance.

  • PDF

Effects of 6 Week Kinesiotaping and Extracorporeal Shock Wave Therapy on the Joint Range of Motion in Patients with Frozen Shoulder

  • Choi, Jung Hyun;Kim, Soon Hee;An, Ho Jung;Koo, Ja Pung;Kim, Nyeon Jun
    • Journal of International Academy of Physical Therapy Research
    • /
    • v.8 no.1
    • /
    • pp.1095-1099
    • /
    • 2017
  • This study used both kinesiotaping and extracorporeal shock wave therapy on patients diagnosed with frozen shoulder - a common musculoskeletal disorder in adults - in order to observe the effects on the joint range of motion. 21 adult(male 12, female 9) were selected and distributed into randomized groups. One group received kinesiotaping (n=10) and the other group received kinesiotaping together with extracorporeal shockwave therapy (n=11). After a 6 week duration of receiving kinesiotaping and extracorporeal shockwave therapy, changes in the joint range of motion in the patients were observed. Post-treatment of frozen shoulder, the changes in abduction within the shoulder joint were as follows: in both groups there was a noticeable increase in the joint range of motion (p<.05). Post-treatment of frozen shoulder, the changes in external rotation within the shoulder joint were as follows: both groups showed a significant increase in the joint range of motion (p<.05). The result of suggest that, it can be inferred that both the extracorporeal shockwave therapy and kinesiotaping are effective in increasing the joint range of motion in patients with frozen shoulder.

Anaphylactic Shock Care during General Anesthesia -A Case Report- (전신마취 도중 유발된 아나필락시스 -증례보고-)

  • Choi, Byung-Ho;Sul, Sung-Han;Yoo, Jae-Ha
    • Journal of The Korean Dental Society of Anesthesiology
    • /
    • v.6 no.2 s.11
    • /
    • pp.121-126
    • /
    • 2006
  • Generalized anaphylaxis is a most dramatic and acutely life-threatening allergic reaction. Most fatalities from anaphylaxis occur within the first 30 minutes postantigenic exposure. The mechanism of generalized anaphylaxis is the reaction of IgE antibodies to an allergen that causes the release of histamine, bradykinin, and others. These chemical mediators cause the contraction of smooth muscles of the respiratory and intestinal tracts, as well as increased vascular permeability. Four major clinical symptoms are recognized: skin reactions, smooth muscle spasm (gastrointestinal and genitourinary tracts and respiratory smooth muscle), respiratory distress, and cardiovascular collapse. Epinephrine is the drug of choice for the management. Its syrnpathomimetic effects directly counteract most aspects of the attack. Respiration must be immediately supported by the establishment of a patent airway along with artificial ventilation. The circulation should be supported and the existing hypotension overcome by placing the victim in a position to allow gravity to aid venous return and by administering intravenous fluids, vasopressors, and corticosteroids. When an imperceptible pulse is evident, external cardiac compression must also be instituted. This is a case report of anaphylactic shock care during general anesthesia, possibly due to penicillin, pancuronium and others.

  • PDF

The Effect of the Global Financial Crisis on Corporate Investment in Korea: From the Perspective of Costly External Finance

  • JEONG, DAEHEE
    • KDI Journal of Economic Policy
    • /
    • v.37 no.1
    • /
    • pp.19-44
    • /
    • 2015
  • This paper examines the effect of the global financial crisis on corporate investment in Korea. Specifically, the crisis was considered to have possibly constrained firm-level investment as the negative shock to the credit supply dramatically unfolded. As Duchin et al. (2010) demonstrated, if a negative supply-side shock is evident during a crisis period, larger cash holdings before the crisis will lead to fewer constraints to corporate investment, or vice versa. In order to investigate the supply-side effect of the crisis, we use firm-level financial data, including firms listed on the Korean stock market as well as small and medium-sized enterprises. We find that corporate investment declined significantly after the crisis, even if we control for factors associated with the demand side, such as contemporaneous capital productivity and cash flow. More importantly, the decline is positively and significantly related to cash holdings before the crisis, implying the negative effect of a credit supply shock. Small and medium enterprises experienced relatively sharp investment declines compared to those of larger firms, and the relationship between pre-crisis cash amounts and the degree of investment decline is greater than that in large firms. Additionally, we examine whether the negative effect persists up to the present, finding evidence that the cash-investment relationship continues in small and medium-sized enterprises.

  • PDF