• Title/Summary/Keyword: CLEARANCE

Search Result 2,376, Processing Time 0.033 seconds

Levitation Control Simulation of a Maglev Vehicle Considering Guideway Flexibility (가이드웨이 유연성이 고려된 자기부상열차 부상제어 시뮬레이션)

  • Han, Jong-Boo;Lim, Jaewon;Kim, Chang-Hyun;Han, Hyung-Suk;Kim, Sung-Soo
    • Journal of the Korean Society for Railway
    • /
    • v.18 no.1
    • /
    • pp.15-24
    • /
    • 2015
  • In magnetic levitation vehicles, the clearance between the magnet and track should be maintained within an allowable range through a feedback control loop. The flexibility of the guideway would introduce additional modes in the overall suspension system, resulting in dynamic interaction between the guideway vibration and the electromagnetic suspension control system. This dynamic interaction can be a serious problem, particularly at very low speeds or standstill, and may cause airgap instability. To optimize the overall system dynamics, an integrated dynamic model including mechanical and electrical parts and a flexible guideway as well as a control loop was developed. With the proposed model, airgap simulations at standstill were performed while varying the control gains, specifically with the aim of understanding the effects of gains of the PID controller on the airgap variation. The findings may be used to achieve a stable levitation controller design.

Magnetic Levitation Control through the Introduction of Bogie Pitch Motion into a Control Law (대차 피치운동을 반영한 흡인식 자기부상제어)

  • Ha, Chang-Wan;Kim, Chang-Hyun;Jo, Jeong-Min;Lim, JaeWon;Han, Hyung-Suk
    • Journal of the Korean Society for Railway
    • /
    • v.18 no.2
    • /
    • pp.87-93
    • /
    • 2015
  • The uneven reaction surface profile facing the lift magnets in attractive Maglev vehicles naturally brings about pitch motion of the bogie. In particular, in the placement configuration of the long stator of the linear synchronous motor (LSM) on the track for high-speed propulsion, surface irregularities and the offsets between the stator packs create measurable airgaps, i.e., the clearance between the magnet and the stator, with discontinuously extreme values, resulting in bogie pitch motion. This occurs because the airgap velocities and accelerations derived by the differentiations of the measured air-gaps are used to determine the voltages applied to the magnets. This paper incorporates bogie pitch motion into a control law for each magnet controller to reduce the variations in both the airgap and the pitch angle. The effectiveness of the proposed method is analyzed using a full-scale Maglev vehicle running over a test track.

Efficient Propulsion of a Container Ship Using the Inclined Keel Concept ("Inclined Keel" 을 이용한 컨테이너선의 추진효율 향상)

  • Seo, Kwang-Cheol;Atlar, Mehmet;Kim, Hee-Jung;Chun, Ho-Hwan;Kang, Dae-Soo
    • Journal of the Society of Naval Architects of Korea
    • /
    • v.44 no.4
    • /
    • pp.379-388
    • /
    • 2007
  • Ever increasing fuel prices and environmental concerns are forcing commercial vessel operators and designers to re-assess current vessel designs with an emphasis on their propulsion systems. The most important parameter determining propulsive efficiency is the diameter of propeller. Many investigations have been carried out to adapt a large and slow turning propeller known as one of the most robust and effective way of achieving high efficiency in ship propulsion system. However, for the same vessel a further increase of propeller diameter would require the modification of the aft end while still paying attention to the hull clearance to prevent excessive propeller excited vibrations. In order to take the advantage of this approach small workboats (e.g. tug boats, fishing vessels etc.) operate in service with a significant increase of aft draught and hence resulting "inclined keel" configuration can be observed. Although it is not unusual to see large vessels sometimes to operate with stern trim to improve their operational performance and fuel efficiency, it is rare to see a such vessel purposely built with an inclined keel feature to fit a large diameter propeller for power saving. This paper investigates the application of the inclined keel configuration to a 3600TEU container vessel with the aim of fitting an 11 % larger diameter propeller (and hence resulting 17.5 % lower rpm) to gain further power saving over the similar size basis container ship with conventional "level keel" configuration.

Bioavailability of Ranitidine Tablets in Rats (흰쥐에서 라니티딘제제의 생체이용률)

  • 이미숙;구영순
    • YAKHAK HOEJI
    • /
    • v.39 no.6
    • /
    • pp.636-644
    • /
    • 1995
  • Comparison of bioavailabflity (BA) of three brands of ranitidine (RT) tablets has been studied m rats. The purpose of this study was to characterize the pharniacolunetics of RT tablets in the rat and to coinpare phannacolunetic parameters of three brands of RT tablets. In addition, it was investigated whether plasma RT concentrations m humans can be predicted from pharmacokinetic parameters obtained in rats. RT was administered intravenously in dose of RT.HCI 10mg/kg and orally in dose of RT.HCI 50mg/kg as solution or crushed sample of thablets. Plasma RT concentrations were determned by HPLC. Plasma RT concentrations as a function of time were fitted to two compartment model. Plasma RT concentrations declined with a terminal half life ($t_{{1}/2{\betha}}$) of 40.9 min. The plasma RT concentration-time curve showed two peak plasma concentrations following an oral administration of solution or crushed sample in rats like humans. No significant difference among pharmacokinetic parameters was observed except $T_{max2}$ (p<0.05). The BA for crushed sample A, B and C were found to be 54.6 40.7 and 40.0%, respectively. Equivalence of $C_{max1}$ and $T_{max2}$ were guaranteed in this study. However, it was concluded that three brands of RT tablets are bioequivalent, taking the following characteristics of RT into consideration;(1) rapid onset of the effect is not required, (2) $C_{max1}$ and $T_{max2}$ do not seem to influence the effectiveness of the drug during a long-term treatment by the usual administration of twice a day. Results from this study were combined with plarmacokinetic data for RT in dogs and humans to develop a basis for interspecies scale-up of the disposition characteristics of the drug. there were similarities in the general disposition of the drug. Allometric relationships were sought between pharmacokinetic parameters nd species body weight. Significant interspecies correlations were found for total body clearance($Cl_{t}$) and steady state volume of distribution ($Bd_{ss}$). Thus, plasma RT concentrations in humans can be predicted from pharmacokinetic parameters obtained in rats.

  • PDF

Pharmacokinetics of PEG-Hemoglobin SB1, a Hemoglobin-Based Oxygen Carrier, after Its Intravenous Administration in Beagle Dogs

  • Kwon, Oh-Seung;Chung, Uoo-Tae;Chung, Youn-Bok
    • Archives of Pharmacal Research
    • /
    • v.27 no.2
    • /
    • pp.259-264
    • /
    • 2004
  • The purpose of the present study was to investigate the pharmacokinetics of PEG-hemoglobin SB 1, a modified bovine hemoglobin with polyethylene glycol, after its single and multiple administration in beagle dogs. For this purpose, the analytical method of free hemoglobin in the plasma was developed and validated. Excellent linearity ($r^2$=0.999) was observed in the calibration curve data, with the limit of quantification of 0.005 g/dL. The precision and the deviation of the theoretical values for accuracy were always within $\pm$15% in both the between-and the within-day results. The method was tested by measuring the plasma concentrations following intravenous administration to beagle dogs and was shown to be suitable for pharmacokinetic studies. In a single dose study, the plasma half-life (t$_{1}$2/) increased and the total body clearance (Cl$_{t}$) decreased with the dose (i.e., 0.017 to 0.75 gHb/kg as PEG-hemoglobin SB1) in both sexes. The volume of distribution at steady-state (Vd$_{ss}$ ) showed no difference with the dose. In contrast, the values of t$_{1}$2/, CL$_{t}$ and the area under the plasma concentration-time curve (AUC) after the multiple dose were significantly different from those of the single dose administration. The values of t$_{1}$2/ in the multiple administration were about two times higher-than that of the single dose. As a result, t$_{1}$2/ of hemoglobin after the administration of PEG-hemoglobin SB1 was about 15-30 h, indicating the PEG modification of the hemoglobin lead to a prolongation of plasma concentration of the protein. Therefore, these observations suggested that the PEG modification of hemoglobin is potentially applicable in the hemoglobin-based therapeutics.tics.

A Study on the Outcome of International Trade Practice in Commitment of Electronic Trade (전자무역의 몰입이 무역업무성과에 미치는 영향에 관한 연구)

  • Lee, Jeong-Ho
    • International Commerce and Information Review
    • /
    • v.14 no.4
    • /
    • pp.545-562
    • /
    • 2012
  • This study tried to analyzed the relationship outcome and commitment in order to suggest to a outcome for commitment decision-making of e-trade. 6 hypothesis were constructed for analysis based on previous literature review. The subject of this study is to analyse on electronic trade practice outcome on the international trade practice commitment. This paper investigates the outcome determinants of e-trade commitment. There are 250 sended samples and 188 returns, 168 of them are analyzed on commitment for a electronic trade outcome. The first, multiple regression result shows that the international trade practice outcome are positively affected by the "Overseas market research commitment", "e-L/C Practice commitment", "Clearance Practice commitment", "e-B/L or global logistic commitment", "Payment or e-Nego commitment". However, The "Commerce practice commitment" factors does not affect in the electronic trade practice outcome.

  • PDF

A Study on the Classification of Nursing Diagnoses by Student Nurses (간호학생이 내린 간호진단 분석에 관한 연구)

  • Min, Soon
    • Journal of Korean Academy of Nursing
    • /
    • v.25 no.3
    • /
    • pp.457-471
    • /
    • 1995
  • This research was done to promote improvement of practical application of nursing diagnoses and to improve the quality of nursing. The subjects of this research were 156 second year students of C junior nursing college who were giving adult patient care. The nursing diagnoses of 312 reports were analyzed using NANDA. In these case reports only nursing diagnoses were considered, of which there were a total of 982. In the data analysis the 9H of the nursing students' nursing diagnoses matched with 105 NANDA nursing diagnoses, Of these, the most frequent diagnoses were pain(165, 17.48%), anxiety(101, 10.70%), alteration in nutrition(83, 8.79%) , sleep disturbance (67, 7.10%), in activity intolerance (67, 7.10%), ineffective breathing pattern(51,5.40%). The etiology for the students' nursing diagnoses were compared with NANDA's nursing diagnoses by frequency. The most frequent etiology for the nursing diagnoses of pain was a biological etiology(50, 31%), for anxiety, situation crisis(58, 57.43%), for alteration in nutrition, indigesion(23, 27.71%), for sleep disturbance, external etiology(25, 37.32%), for activity intolerance, immobile position(22, 32.84%), for ineffective breathing pattern, pain(35, 68.63%), and for ,impaired physical mobility, pain(31, 65.96%). The most frequent etiology for constipation was inadquate digestion of water and cellulose (16, 34.78%), for fluid volume felicity, loss of body fluid (21, 52.50%), for impaired skin integrity, external etilogy(16, 43.24%), for impaired physical mobility, pain(22, 62.86%) , for knowledge deficits, cognition disturbance(9, 27.27%), for ineffective air way clearance, secretion obstruction(14, 48.27%) , for impaired gas exchange, loss of transport ability of blood oxygen(9, 37.50%) , and for powerlessness, therapy environment (5, 22.73%). The number of nursing diagnoses by pattern was exchange(16), moving(6), feeling(4), choosing(4), relating(3), communication(1), perceiving(1), knowing(1), valuing(1).

  • PDF

The Characteristics Analysis of The PCB Pattern for The Mobile panel Power Supply on The PMIC (모바일 패널 전원 공급을 위한 PMIC의 PCB 패턴의 특성 분석)

  • Chung, Sung-In;Kim, Seo-Hyeong
    • Journal of the Institute of Electronics Engineers of Korea SD
    • /
    • v.48 no.6
    • /
    • pp.39-44
    • /
    • 2011
  • This purpose of this study is to propose the characteristics analysis of the PCB pattern designed two modes for the output voltage value on the PMIC through converting the limited voltage value inputted from a battery. The PCB design technology has been undergoing difficulty in getting the related technology in a domestic market because of increasing EMI/EMC, Cross-talk, Impedance. And it requires to have the appropriate clearance between the patterns and the technology of PCB pattern width with a amperage according to various uses. The study carried out the characteristics analysis of the PCB pattern designed from a direct output method without a capacitor[mode1], to an output method through a capacitor[mode2] for PMIC output voltage value. Besides, we calculated the pattern width with a amperage using the equation suggested by IPC-2221, presenting the right way of the layout design to analyze the trouble with the test. Therefore, this study is expected to contribute not only to applying the PMIC design for the mobile panel power supply, but also helping the design and application technology in various areas such as car control, camera, note-book, computer, PDA, etc.

Study on the Development of Home Care Nursing Intervention Protocol for Stroke Patients (뇌졸중 환자의 가정간호중재 프로토콜 개발)

  • Yoo Ji-Soo
    • Journal of Korean Academy of Fundamentals of Nursing
    • /
    • v.7 no.1
    • /
    • pp.122-136
    • /
    • 2000
  • Stroke patient needs rehabilitation after receiving an acute treatment in a hospital. When stroke patient gets involved in an early discharge program, home care nurse plays a pivotal role to make them to gain a full strength and to come back to his/her prior life before he/she is sick. In spite of the importance of home care nursing intervention protocol for home care nurses to perform home care nursing autonomously, home care nursing intervention protocol for stroke patient is rarely developed. Therefore this study was conducted to develop home care nursing protocol that is applicable for stroke patients in home care nursing area. 41 home care nursing charts for stroke patients registered in home care nursing agencies from December 1st 1994 to August 31st 1999 at Y hospitals in Seoul and Won-Ju city were analyzed. 44 home care nurses who were having over three years' experience on stroke patients were participated in this study as a user validity validation group. The results of this study are as follows. 1. 28 nursing diagnoses were selected on the basis of evaluation of nursing diagnoses of stroke patients presented in a previous literature and case studies on home care nursing. 2. 17 nursing diagnoses were classified through the frequency analysis of home care nursing charts for 41 stroke patients who had received home care nursing. The order of sequence was like these: impaired skin integrity, risk for infection, nutritional deficit, impaired physical mobility, constipation, knowledge deficit, ineffective airway clearance, anxiety in family members, risk for aspiration, self care deficit, altered urinary elimination, ineffective individual coping, social isolation, risk for injury, self-esteem disturbance, impaired verbal communication, fatigue of family caregiver. 3. Based on validation on expert and user validities, 44 nursing interventions which were above ICV=.80 were chosen. 4. Nursing intervention protocols which showed above ICV=.90 were developed and were like these; pressure ulcer care, position change, preventive care for circulatory dysfunction, tube care : catheter, vital sign monitor, constipation/impaction management, artificial airway management, suction of airway secretion, environmental management : safety, and fall prevention.

  • PDF

A Case of Kartagener's Syndrome Presenting as Respiratory and Right Heart Failures (호흡부전과 우심부전을 동반한 Kartagener 증후군 1예)

  • Yang, Suck-Chul;Lee, Kyung-Sang;Yoon, Ho-Joo;Shin, Dong-Ho;Park, Sung-Soo;Lee, Jung-Hee;Park, Choong-Ki
    • Tuberculosis and Respiratory Diseases
    • /
    • v.43 no.2
    • /
    • pp.251-256
    • /
    • 1996
  • Kartagener's syndrome, a congenital disease transmitted as an autosomal recessive illness with a prevalence of approximately 1:20,000 persons, is characterized by the triple association of situs inversus, bronchiectasis, and sinusitis. Affected persons have an incoordination of ciliary motility that leads to defective mucociliary transport, chronic bronchial infections. Kartagener's syndrome is a subset of the immotile cilia syndrome and therefore all patients with Kartagener's syndrome have immotile cilia with obvious ultrastructural defects in the ciliary axoneme. In the respiratory tract this inability presumably causes impaired clearance of mucus and inhaled particles and results in the chronic infections of the sinuses and bronchial trees that are characterized of the disease. The end-stage phenomenon in Kartagener's syndrome, respiratory or heart failure is a less common event and heart-lung transplantation is becoming an accepted therapy for patients with end-stage pulmonary disease in Kartagener's syndrome in many institutes. We report one case of Kartagener's syndrome in a 25-year-old young woman who was presented as respiratory and right heart failures, with review of literatures.

  • PDF