• The Korean Journal of Ceramics
• /
• v.5 no.3
• /
• pp.296-302
• /
• 1999

The state of the art of the 2-stage swirl calciner is to make 2-stage counter gas flow in a calciner with cooler hot air. Gas flow in the calciner increases retention time of raw mix particles. Simple structure of the 2-stage swirl calciner operated optimally the rotary cement kiln. In this study, in order to decide the entrance type of the cooler air of the optimal calciner model, an entrance cooler air velocity, the input points of raw mix were analyzed in many aspects with cold model experiment and computational fluidized dynamic simulation. It was found that the entrance type of cooler air fully splite 2-stage for the optimal condition of the cold model calciner. The operation conditions were that the input feeding, the cooler air velocity and the air velocity of throat were 0.33kg/$\textrm m$3$, 15m/s and 20m/s respectively. The performance of 150 t/d the pilot plant connected with the kiln rising duct was that volume capacity of the calciner is over 430 kg/$\textrm m$3$-h, decarbonation rate of raw mix apparently 90%, heat consumption 950 kcal/kg-cli and retention time of raw mix 2.4 sec. Its the best operating condition is cooler air velocity 18m/s, the gas velocity of throat 25m/s, feeding rate of raw mix 10t/h. The operating experience of the pilot plant confirmed the success of scale up for over 3000 t-cli/d.

• Journal of Environmental Policy
• /
• v.12 no.2
• /
• pp.17-32
• /
• 2013

The potential impact of water temperature on air temperature in response to recent anthropogenic global warming has been noticed. To predict climate, induced change in river aquatic environment, it is necessary to understand the thermal constrains of fish species and the timing of the projected river temperature. As a preliminary study, air-water temperature relationship was analyzed on the basis of the observed data during the time period of 2009-2011 and the number of data corresponds to 873-1083. As a result of analyzing the auto-and cross-correlation coefficient between air-water temperature, high correlation is shown (~0.9). It is also found that the correlation coefficient of air temperature is higher than that of water temperature at the lag time less than approximately 10 days. Observed data was divided into two groups to investigate hysteresis: rising limb and falling limb. For some stations there is strong evidence that hysteresis exist between air-water temperature relationships. Consequently it is recommended that seasonal hysteresis needs to be included in determining an airwater relationship.

• Journal of the Korean Society for Nondestructive Testing
• /
• v.32 no.1
• /
• pp.1-6
• /
• 2012

This study is damage evaluation for CNG fuel tank during the burst test through the analysis of acoustic emission signals. Kaiser effect until the pressure 420 bar appears, but More than 420 bar by the creep effect appears significantly damaged vessels, and 480 bar pressure, the Kaiser effect of the rising phase was missing. Resonant transducer at 540 bar than 480 bar decreased activity such as energy and count Continually, but increased wideband transducer. In addition, through the rise time or frequency analysis of composite pressure vessels in order to observe the damage mechanisms wideband transducer is more effective than resonant transducer.

• The Journal of the Acoustical Society of Korea
• /
• v.15 no.1E
• /
• pp.5-19
• /
• 1996

This paper proposes a loose part monitoring system (LPMS) design with a signal processing method based on fuzzy logic. Considering fuzzy characteristics of metallic impact waveform due to not only interferences from various types of noises in an operating nuclear power plant but also complex wave propagation paths within a monitored mechanical structure, the proposed LPMS design incorporates the comprehensive relation among impact signal features in the fuzzy rule bases for the purposes of alarm discrimination and impact diagnosis improvement. The impact signal features for the fuzzy rule bases include the rising time, the falling time, and the peak voltage values of the impact signal envelopes. Fuzzy inference results based on the fuzzy membership values of these impact signal features determine the confidence level data for each signal feature. The total integrated confidence level data is used for alarm discrimination and impact diagnosis purposes. Through the perpormance test of the proposed LPMS with mock-up structures and instrumentation facility, test results show that the system is effective in diagnosis of the loose part impact event(i.e., the evaluation of possible impacted area and degree of impact magnitude) as well as in suppressing false alarm generation.

• 제어로봇시스템학회:학술대회논문집
• /
• 1992.10b
• /
• pp.265-271
• /
• 1992

It is the purpose of this paper to present a dialogical designing method for control system using a rough grasp of the unknown process property. We deal with a single-input single-output feedback control system with a fuzzy controller. The process property is roughly estimated by the step response, and the fuzzy controller is interactively modified according to the operator's requests. The modifying rules mainly derived from computer simulation are useful for almost every process, such as an unstable process and a non-minimum phase process. The fuzzy controller is tuned by taking notice of four characteristics of the step response: (1) rising time, (2) overshoot, (3) amplitude and (4) period of vibration. The tuning position of the controller is fourfold: (1) antecedent gain factor GE or GCE, (2) consequent gain factor GDU, (3) arrangement of the antecedent fuzzy labels and (4) arrangement of the control rules. The rules give an instance to the respective items of the controller in an effective order. The modified fuzzy PI controller realizes a good response of a stable process. However, because the GDU tuning becomes difficult for the unstable process, it is necessary to evaluate the stability of the process from the initial step response. The fuzzy PI controller is applied to the process whose initial step response converges with GDU tuning. The fuzzy PI controller with modified sampling time is applied to the process whose step response converges under the repeated application of the GDU tuning. The fuzzy PD controller is applied to the process whose step response never converges by the GDU tuning.

• Journal of Fisheries and Marine Sciences Education
• /
• v.18 no.2
• /
• pp.77-84
• /
• 2006

This research evaluates thermal comfort by comparing the case of maintain cooing temperature of room with the case of raising it at the point of time that human body begins to adapt. An experiment uses constant temperature & humidity chamber 2 places. Pretesting room make up summer season environment, the testing room control by air-conditioner. In condition that maintain temperature of $33^{\circ}C$. The subjects stay in the pretesting room during the 30 minute for the heat storage amount of the normal summertime. The subjects stay in the testing room under each case (case 1: maintaining $24^{\circ}C$, case 2: maintaining $26^{\circ}C$, case 3: up $1^{\circ}C$ after maintaining $24^{\circ}C$ during 30 minute, case 4: up $1^{\circ}C$ after maintaining $26^{\circ}C$ during 40 minute). 1. Result of comparison of case 1 and case 2 appears that thermal sensitive vote examine from slight cool to cool and thermal comfort examine slight comfort by temperature rise at human body adaptation point of time.2. Test of case 3 and case 4 appear similar value at thermal sensitive vote and thermal comfort.3. Through the case 2 and case 4, continuous thermal comfort maintain at $24^{\circ}C$, if raise $26^{\circ}C$, same thermal comfort maintain after a human body adaptation temperature rising effect bring energy saving.

• Journal of the Korean Society of Radiology
• /
• v.9 no.7
• /
• pp.523-528
• /
• 2015

In this study, we evaluated the heating characteristics of single sonication and superposed two low-intensity ultrasonic sonication. Compare the results, the superposed sonication was showed a superior thermal effect than single sonication. And the maximum temperature was increased as 120-150%. The starting time of temperature rising has been shortened in superposed sonication. In addition, the time up to the maximum temperature has been shortened, too. In generally, as the ultrasonic intensity is higher, the more surface damage is occurred. However, in the case of superposed sonication, the same thermal effect had be confirmed without surface damage. Through the results of the study, we thought that the superposed sonication will be able to reduce the intensity of the ultrasonic treatment. And, by using the low-intensity, the more safe and more effect therapy will be possible in therapeutic ultrasound application.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
• /
• v.5
• /
• pp.7-44
• /
• 1993

This study is focused on the review of buyer's remedy resulting from the breach of seller's duty in contracts for the international sale of goods focusing on UNCCIS, 1980 and the problems and suggestions of proper ideas for solving the problems. First problem on the buyer's remedy is related to the breach of seller's duty on del ivory of the contracted goods. When seller has failed to deliver the contracted goods to buyer within the stipulated periods, buyer can treat the contract as avoided and claim damages from seller. By the way, since UNCCIS does not provide any stipulation on the time of buyer's avoidance of the contract, buyer can delay the time of avoidance when the price of contracted goods is rising rapidly and enlarge the amount of damages, Since this stipulation is clearly unreasonable, proper solutions are required for UNCCIS. Second problem is related to the breach of seller's duty on deliver of goods which are of the quantity, quality and description required by the contract and which are contained or packged in the manner required by the contract. When seller has failed to deliver goods which are confirm with the contract, buyer may have one of the two rights of damages and the price reduction according to UNCCIS provided that he does not choose the avoidance. But, since the character and position of the price reduction as a buyer's remedy are not sufficient solutions, more detailed review on this point is required. Third, Seller's duty to provide documents is very important for overseas trade, but UNCCIS does not provide any specific buyer's remedy in comparison with the other remedy and also does not provide any stipulation on the Letter of Credit which have important roles for a device of setting payment in overseas trade. This means that trade customs and practice have not sufficiently reflected in UNCCIS. As the problems mentioned above may decrease the evaluation of buyer's remedy in UNCCIS and, furthermore, that of UNCCIS itself, proper solutions on these points are needed.

• Journal of Korea Multimedia Society
• /
• v.13 no.1
• /
• pp.143-152
• /
• 2010

Because of a rising in the standard of living and the development of medical technology, Korea is expected to become an aging society more than 14% elderly population and the silver generation will be responsible for the large portion of economic activities. The silver generation has relatively diminished in perception, learning, and exercise due to the physical aging. Therefore, it is important the development of game contents which can constantly provide the maintenance function of physical and mental health and the functional exercise with spending the leisure time. In this paper, we suggest a design method for developing the game contents which are able to help the silver generation to strengthen their lower extremities and to enjoy their leisure time. The proposed method will enable to lead the silver generation to carry on the physical activities with the amusement of playing a game through the functional design concepts appropriate for the ability of the silver generation's perception and physical activities, an adaptive game process customized by the individual capability and a user-friendly sensory interface.

• Journal of Korean Society of Occupational and Environmental Hygiene
• /
• v.29 no.4
• /
• pp.603-609
• /
• 2019

Objectives: This case report aims to contribute to the enhancement of training quality for occupational accident prevention by conducting surveys on customers' satisfaction with the training course management by the Occupational Safety and Health Training Institute (OSHTI) of KOSHA. Methods: Surveys were conducted through phone calls, customer service documents, and questionnaires from January 1, 2018 to December 31, 2018. Results: The surveys showed an answer rate of 97.36% and handling rate of 97.47% in 2018, an increase of 1.15% compared to 2017. The number of monthly inbound calls in 2018 was 5,902, rising 0.10% year-on-year, and the average inbound calls per day in 2018 was 289, a decline from 291 the year before. The number of provisions of customer service in 2018 was 68,952, increasing 1.89% year-on-year. The number of inquiries on the training curriculum was 58,744 in 2018, an increase of 3.98% compared to the 56,498 recorded in 2017. Inquiries on job training centers were the most common, numbering 27,114 (39.32%), followed by e-learning 18,470 (26.79%) and expert courses 13,160 (19.09%). Of the 149 answers to the customer service survey, 'Nothing to complain about' accounted for 86 (56.72%) and 'Diversifying training time and programs' numbered 22 (14.77%). Conclusions: Customer satisfaction in 2018 increased compared to that in 2017. However, there is a need to reflect the demands of customers for diversifying training time and programs, offer practice-centered training, and collect opinions on providing information in order to maintain high quality training course management.