• 한국생물공학회:학술대회논문집
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• 2001.11a
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• pp.274-277
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• 2001

This research was conducted as a part of continuous development of a bioprocess to treat thiocyanate($SCN^-$) in the leachate from an industrial landfill site. Detailed characteristics of the leachate, physical and chemical, was analyzed in this study. Time to reach equilibrium in $SCN^-$ degradation at different temperature, similar to the annual variation. was investigated for posssible adaptation of the bioprocess in the treatment site. Complete mineralization of $SCN^-$ to ammonia. bicarbonate and sulfate at all temperature range with except $5^{\circ}C$ trial was observed with different time elapsed to reach equilibrium. which shortened as the process of Fill-Draw proceeded. The final metabolites were mainly nitrate and sulfate. No fouling odor was detected and the settling characteristic of the biomass after the treatment was good(i.e., sludge volume index(SVI) ${\le}$80). Using MWT sludge as an inoculum showed better performance with respect to the elapsed time for treatment and sedimentation characteristics than those of using 2BET sludge.

• Journal of Environmental Health Sciences
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• v.32 no.1 s.88
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• pp.53-59
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• 2006

This study was carried out to investigate the physicochemical characteristics with the elapsed time of $1\~10$ minutes after adding green tea leaves in the tap water. The results are summarized as follows: 1. $UV_{254}$ measurement increased sharply in direct opposition to increasing conductivity slowly. It is expected that the water soluble organic matters were better extracted than minerals. 2. Residual chlorine decay coefficients evaluated by assuming first-order reaction was increased in proportion to adding weights of green tea leaves. 3. In DBP formation experiments, residual chlorine decreased when reaction time was elapsed. whereas DBPs such as HAAs and THMs increased with the passing of time. From these results, it was showed that residual chlorine decay was related with the formation of DBPs. Therefore, use of boiled tap water in preparation of green tea is suggested if the residual chlorine in the tap water is high.

• Textile Coloration and Finishing
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• v.11 no.2
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• pp.27-37
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• 1999

Polypropylene(PP) films were treated with plasma glow discharge to produce peroxy radicals on the surfaces. The peroxy radicals formed on the PP film surfaces were subsequently used for the graft polymerization of acrylic acid and acrylamide in an aqueous solution by heating, respectively. Introduction of acrylic acid and acrylamide on the PP film could be confirmed by the observation of carbonyl and primary amine absorptions based on carboxylic acid and amide, respectively. And introduction of functional group could be confirmed by weight analysis and ESCA. The water contact angle(90$^{\circ}$) of PP film was constant, irrespective of elapsed time, while plasma-treated and functional monomer-grafted PP films were slowly increased with elapsed time, showing the rearrangement of surface polar groups in air condition. The water contact angle$(90^\circ)$ of PP film was decreased by the plasma treatment$(56^\circ)$ and further decreased by the grafting of acrylic acid$(34^\circ)$ and acrylamide$(37^\circ)$, indicating increased hydrophilicity of the modified surfaces. The water contact angle of plasma-treated PP film increased a little as time elapsing. The half-life periods of surface voltage on acrylic acid-(31sec) and acrylamide-grafted PP(42sec) were significantly decreased when compared to those on PP(950sec) and plasma-treated PP film(241sec). In the experiments using acid, basic and disperse dyes, absorbance and $\Delta{E}$ values of functional monomer-grafted PP films were significantly increased than that of oxygen plasma-treated one.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.18 no.5
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• pp.477-482
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• 2009

This study analyzes the result with dynamic simulation about deformation according to time when a car impacts bollard. These results are shown as followings. The maximum deformation is shown at the lower part of front grass in case of the impact of front or passenger seat but this deformation is shown at the lower part of rear bumper in case of double impact. The maximum equivalent stress is shown at the upper part by the side grass of driver seat at the elapsed time of 0.00075 second after impact in case of the impact of front or passenger seat but this deformation is shown at the front bonnet at the elapsed time of 0.004 second after the additional impact in case of double impact. The maximum total deformation or equivalent stress is shown nearly same in case of the impact of front or passenger seat. But the value of this deformation or equivalent stress in case of the impact of front or passenger seat is shown with 2 times or more than 17% respectively as this value in case of double impact.

• Journal of the Korea Convergence Society
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• v.11 no.12
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• pp.457-467
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• 2020

This study was conducted to for the development of nursing education programs suitable for the period by identifying the unmet needs of kidney transplant surgery patients who need continuous self-care according to the elapsed period. The subjects of the study consisted of 84 inpatients and outpatients for up to 1 year after kidney transplant surgery. The data collection period was from February 17 to May 31, 2020, and the collected data were analyzed by Chi-square, independent t-test, one-way ANOVA, and post-test by Scheffé using the IBM SPSS 21.0 program. As a measurement tool, the Comprehensive Needs Assessment Tool in Cancer(CNAT), a tool to assess unmet needs of cancer patients, was modified and supplemented to receive expert validity, and then self-report through a questionnaire consisting of a total of 57 questions. As a result of the study, the average of the total score out of 171points for the unmet needs of kidney transplant patients was 68.28(±38.88), and information and education accounted for the highest score of 17.92(±8.36) out of the eight sub-areas. The unmet needs according to the elapsed period were significantly higher in the 6 months ~1 year group(F=7.57, p=.001) compared to the 3-6 months group. Based on this, it is necessary to develop a nursing intervention program that can provide appropriate information and support at a time when the unmet needs of patients up to increase from 6 months to one year after kidney transplantation increase.

• School Mathematics
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• v.19 no.3
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• pp.513-531
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• 2017

This study aims to analyze and compare Korean mathematics textbooks on time and to induce its educational implications. Concretely, the mathematics textbooks from the 1st to the 2009 national revised curriculum were selected for the longitudinal analysis. In each textbook, the contents such as clock reading, units of time, and calculation of elapsed time among various contents about time were chosen. The learning elements and their teaching sequence, the teaching method (the introducing ways of each concept and principle), and the didactical representations are set as an analysis framework. The results of analysis revealed many characteristics and differences in ways of dealing contents about time. Based on these results, we suggested several implications for writing the unit of time in elementary mathematics textbooks and teaching about time in classrooms.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.38 no.3
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• pp.117-126
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• 2015

This paper is to analyze an integrated production and inventory model in a single-vendor multi-buyer supply chain. The vendor is defined as the manufacturer and the buyers as the retailers. The product that the manufacturer produces is supplied to the retailers with constant periodic time interval. The production rate of the manufacturer is constant for the time. The demand of the retailers is constant for the time. The cycle time of the vendor is defined as the elapsed time from the start of the production to the start of the next production, while the cycle times of the buyer as the elapsed time between the adjacent supply times from the vendor to the buyer. The cycle times of the vendor and the buyers that minimizes the total cost in a supply chain are analyzed. The cost factors are the production setup cost and the inventory holding cost of the manufacturer, the ordering cost and the inventory holding cost of the retailers. The cycle time of the vendor is investigated through the cycle time that satisfies economic production quantity with the production setup cost and the inventory holding cost of the manufacturer. An integrated production and inventory model is formulated, and an algorithm is developed. An numerical example is presented to explain the algorithm. The solution of the algorithm for the numerical examples is compared with that of genetic algorithm. Numerical example shows that the vendor and the buyers can save cost by integrated decision making.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1990.04a
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• pp.220-221
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• 1990

The objective of this study is to determine a near-optimal time schedule for processing necessary jobs in order to minimize total elapsed time. The fundamental assumptions are that jobs to be processed are classified into several groups and jobs within the same group are processed in succession in the flow-type GT line. A heuristic method by V. A. Petrov is applied to determine the job sequencing. In consideration of production quantity, group sequences and job sequences for each group are determined and the start time of processing for each job is calculated by computer.

• Plant Journal
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• v.12 no.1
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• pp.24-28
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• 2016

In desulfurization facilities of oil-fired power plant, gypsum scale is attached in the absorber inner surface as the operating time increases. For this reason, the maximum possible load of the power generation is set down, resulting in further generation stop. Cleaning of absorber for scale removal can be determined at the time of setting down of the maximum possible load. In this study, 6 weeks before the maximum possible load of the power generation was down set, at the same time and desulfurization facilities outlet $SO_2$ concentration value was more than 130ppm, absorber differential pressure exceeded $380mmH_2O$, it was confirmed to be the time that has elapsed 44 weeks after the previous absorber cleaning. Cleaning time of the absorber was predicted to be a time which has elapsed 50 weeks from the previous cleaning time.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.42 no.3
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• pp.595-603
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• 2017

We propose a scheme to reduce the time for the SSL/TLS handshake by embedding it into the TCP 3-way handshake. The scheme can be selectively applied on the standard TCP for making the SSL/TCP handshake happen within the TCP handshake, rather than performing the TCP handshake and SSL/TLS handshake in sequence. We implemented a prototype of the scheme and did some experiments on its performance. Experimental results showed that, compared to the sequential handshakes of the TCP and the SSL/TLS, the time reduction achieved by the scheme varied in the range of 3.2% and 14%(when the elapsed time by the ping program from the client to the server was 11.6ms). The longer the time measured by the ping program, which would grow as the propagation and queuing delays do, the larger the reduction rate. It accords with the supposition that the reduced time due to the scheme will increase in proportion to the amount of the elapsed time measured by the ping program.