• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.21 no.10
• /
• pp.547-557
• /
• 2020

In this study, damping control devices were applied to the suspension system of a capsule train, and the effects were investigated to improve the ride comfort. The superconductor electrodynamic suspension (SC-EDS) method is used for the capsule train levitation. This method has advantages such as no gap control and a large gap. However, the SC-EDS method has disadvantages such as large gap variation and small damping characteristics against outer vibration, which causes degradation of the ride comfort. In this study, the damping control devices in the primary and secondary suspension were considered to improve the ride comfort in the capsule train. Damping control devices in the primary and secondary suspension can reduce the vibration transmission from outer disturbances to the bogie and from the bogie to the car body, respectively. Simulations for dynamic characteristics analyses were conducted based on the capsule train dynamic model to investigate the effects of the damping control devices on the ride comfort. As a result, it was confirmed that the ride comfort requirements according to the ISO standard can be satisfied by applying the damping control in the capsule train suspension.

• Proceedings of the KSR Conference
• /
• 2011.10a
• /
• pp.311-319
• /
• 2011

Track accompanies the process that track alignment by traffic loads is changed. A change of track alignment affects the running safety and riding comfort of train. This is called a track irregularity. The most important task in maintaining the track is to manage these track irregularity within quality parameters. Today, track maintenance of urban transit is enforcing immediate maintenance about section exceeding a safety standard by applying track recording data got through Integrated Measurement. This method is advantage of being easy of the maintenance assesment in case of the running safety, but is disadvantage of being difficult in case of the riding comfort of train. In this study, we propose track irregularity deviation of each track system depending on the time series and present about utilization plans of the Track Irregularity Progress Rate.

• Proceedings of the KSR Conference
• /
• 2011.10a
• /
• pp.1624-1630
• /
• 2011

Currently the train operating environment to affect track irregularity is changed rapidly such as speed-up, linear improvement and rolling stack upgrade. The recent track maintenance criteria of track irregularity was quoted from past Japan's, and the needs of revision of criteria are increased because of the rapid change in train operating environment. In case of enhance the track irregularity criteria, it secure driving safety and riding comfort but maintenance cost are increase. And also decrease ballast durability by frequent corrective work. In case of mitigate the criteria, it decrease driving safety and riding comfort, but save the maintenance cost. The study for enacting rational criteria did not carry out so far. In this study, survey the domestic and international track irregularity and case study for track irregularity inspection results and maintenance history for guideline of enacting irregularity criteria study.

• Proceedings of the Computational Structural Engineering Institute Conference
• /
• 2007.04a
• /
• pp.751-756
• /
• 2007

In this paper, perception threshold for horizontal vibration of tall buildings was investigated. After a comparative study of human comfort criteria for wind-induced vibration in foreign countries being made, perception threshold was recorded by increasing acceleration in the range of 0.2Hz through 1.2Hz of frequency in horizontal vibration experiments, and perception of subjects was examined by a proper questionnaire. Also, the results obtained from experiments of horizontal vibration were compared with Japanese standard(AIJES-A001-2004).

• Proceedings of the KSR Conference
• /
• 2003.10c
• /
• pp.28-35
• /
• 2003

In this paper, the ride comfort of a passenger coach installed with a KT23 type bogie was measured and evaluated through field test in operation routes. The ride comfort level was evaluated and analysed by ISO method and DIC method that were applied generally at railway fields. Particularly three evaluation methods, i.e., a simple method, a full standing method, and a full seating method of UIC513R standard, were fully applied to evaluate the ride quality. Also the vertical and lateral vibration levels on the floor were evaluated by peak-to-peak analysis method.

• Journal of the Korean Society of Clothing and Textiles
• /
• v.10 no.2
• /
• pp.37-50
• /
• 1986

The purpose of this study is to compare and to analyse the difference of middle school girls clothing behaviors and their preference for clothing styles according to their intelligence, socio-economic status, and physical constitution. For the study, data were collected from 378 middle school girls resided in Taegu: one half from high intelligence group over I.Q. 113, others from low intelligence group under I.Q. 87 using the questionaire method. For the measurement of the relationship clothing behavior, socio-economic status. Rohrer index, preference style of clothing were examined. The analysis of the data was managed by computer; frequency, percentage, mean, standard deviation, t-test, and ANOVA. The results of the study are as follows; 1. The significant difference in clothing behavior according to intelligence was verified in four: modesty, comfort, management, and psychological dependence. 2. The significant difference in clothing behavior according to socio-economic status was verified in all of eight clothing behavior variables. 3. There was no significant difference according to physical constitution in all clothing behavior variables. 4. There was no significant difference in the preference styles of clothing according to intelligence, but high intelligence group took more interest in detailed factors; design, style, total combination, color, print, and comfort. 5. The upper and middle class preferred slacks and lower class preferred skirts. The upper class took interest in design-style, total combination, and comfort, the middle class in total combination. and comfort, and the lower class in total combination. 6. Thin group preferred skirt, the average group preferred slacks, fatty group preferred slacks and shirts-blouse. Thin group took interest in design-style, and color-print, the average group in total combination, and fatty group in total combination, color-print, and design-style.

• 한국태양에너지학회:학술대회논문집
• /
• 2009.04a
• /
• pp.115-120
• /
• 2009

The studies for mechanical performance development have been examined to reduce energy consumption in building construction field. However, The energy consumption using in building for heating is impacted by not only system performance but also PMV particularly at temperature and clo. Most energy using in building part is mainly consumed for heating and cooling to keep comfort temperature. Heating energy consumption is bigger than cooling energy in Korea because of temperature difference in winter in comparison with summer at apartment building. This means that energy consumption can be changed by occupancy's comfort setting temperature in apartment building. This study evaluate actual comfort temperature range by clo and examined heating energy consumption by Esp-r and CO2 reduction possibility. The results show that keeping ASHRAE standards can reduce heating energy up to 23%; also, wearing underclothes with ASHRAE standard can reduce heating energy up to 47.8%. Option 4 showing Maximum CO2 emission reduction indicates that kerosene. LNG and electricity can reduce 1.5t, 1.7t, 2.46t respectively in comparison with option 2.

• Journal of Fisheries and Marine Sciences Education
• /
• v.18 no.1
• /
• pp.11-18
• /
• 2006

Man has always striven to create a thermally comfortable environment. This is reflected in building traditions around the world - from ancient history to present day. Today, creating a thermally comfortable environment is still one of the most important parameters to be considered when designing buildings. It is defined in the ISO 7730 standard as being "That condition of mind which expresses satisfaction with the thermal environment". A definition most people can agree on, but also a definition is not easily converted into physical parameters. Thermal comfort is a matter of many physical parameters, and not just one, as for example the air temperature that is set by air-conditioner. The most important matter Today's common offices and homes are only depending on air-conditioning as a cooling system during the summer. This kind of system tends to be focused on the person who controls it and those who are around the air-conditioner while thermal-comfort is neglected. Futhermore, the people's body conditions are not considered during each time that beginning, middle, last of the air-conditioning which causing displeasure of the residents more and more. This kind of operating system is set for a long time may causes unbalanced air condition and man's psychologic displeasure goes to increase.

• Journal of Dental Anesthesia and Pain Medicine
• /
• v.22 no.5
• /
• pp.349-356
• /
• 2022

Background: Awake fiberoptic intubation (AFOI) is the procedure of choice for securing the airway in patients with a difficult airway when undergoing surgeries under general anesthesia. An ideal drug would not only provide conscious sedation but also maintain spontaneous ventilation, smooth intubation conditions, and stable hemodynamics. We compared the effects of dexmedetomidine alone and dexmedetomidine in combination with fentanyl at a dose lower than the standard dose for achieving conscious sedation during AFOI in difficult airway patients undergoing oral cancer and dental surgeries. Methods: We included 68 adult patients undergoing AFOI. The patients were randomized in two groups, wherein Group D received intravenous dexmedetomidine 1 ㎍/kg and Group DF received dexmedetomidine 0.5 ㎍/kg and fentanyl 1 ㎍/kg. The outcomes measured were airway obstruction score, intubation scores, fiberoptic intubation comfort score, sedation score, and hemodynamic variables. Results: Low-dose dexmedetomidine with fentanyl showed similar results as those with the standard dose of dexmedetomidine in terms of airway obstruction, vocal cord movement, degree of cough, degree of limb movements, and intubation comfort. However, the sedation achieved and incidence of hypotension and bradycardia were higher in Group D than in Group DF. Conclusions: A low dose of dexmedetomidine-fentanyl provides satisfactory intubation conditions as those with a standard dose of dexmedetomidine in AFOI, thereby avoiding bradycardia, hypotension, and sedation.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2009.10a
• /
• pp.781-786
• /
• 2009

The thesis shows that we gauged vibration of vehicular load regarding WPC girder bridge and researched into dynamic characteristics(natural frequency, vibration acceleration) of WPC girder bridge. By the basic of that, we researched on vibration serviceability by looking over and being compared to vibration criteria we had before. In the thesis, the gauged vibration made an analysis of vertical acceleration through FFT method and evaluated vibration serviceability about vibration sense the body feels by means of the standard of ISO assessment standard and Meister assessment standard by referring to analysis data. This research on bridge is WPC girder bridge of 90m span, width of 5.5m, and the experiment was gauged by a fluent which is right way and inverse way about dump truck of gross 270kN. Acceleration was located in the middle of 1st span, 2nd span, 3rd span. As a result of appraisal standard of Meister, the vibrations of the bridge have distributed between "Level C, Strongly Perceptible" and "Level B, Disturbing". Also the vibration can be attacked with unpleasant feeling. As a result of appraisal standard of ISO, from vibration influence didn't come to 60s, and reduced comfort boundary in part of most rigorous standard that such a case didn't happen.