• 교통기술과정책
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• 제10권5호
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• pp.6-10
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• 2013

• 국제학술발표논문집
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• The 6th International Conference on Construction Engineering and Project Management
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• pp.101-103
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• 2015

Scientific methods that measure the physical demand requirements of a construction operation have not been arrived at maturity in construction community. It is attributed to the difficulty involved in performing controlled experiments on the operation and its' volatile jobsite environment. This paper presents a method that measures the physical demand requirement of the waterproofing activity and verifies the differences between various operations (e.g., a primer painting and a polyurethane coating) consisting of the activity. Two hypotheses, which are involved in the operations, are summarized as follows: [Hypothesis 1] when one performs the same amount of work; the one's average heart rate required for the polyurethane coating operation is higher than that required for the primer painting operation. [Hypothesis 2] when one performs the same amount of work, the one's break time required for the polyurethane coating operation is longer than that required for the primer painting operation.

• The Journal of Advanced Prosthodontics
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• 제14권4호
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• pp.212-222
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• 2022

PURPOSE. To evaluate and compare the effect of impression type (conventional vs digital) and the number of implants on the time from the impressions to the generation of working casts of mandibular implant-supported fixed completearch frameworks, as well as on patient satisfaction. MATERIALS AND METHODS. 17 participants, 3 or 4 implants, received 2 types of digital impression methods (DI) and conventional (CI). In DI, two techniques were performed: scanning with the scan bodies (SC) and scanning with a device attached to the scan bodies (SD) (BR 10 2019 026265 6). In CI, the making of a solid index (SI) and open-tray impression (OT) were used. The outcomes were used to evaluate the time and the participant satisfaction with conventional and digital impressions. The time was evaluated through the timing of the time obtained in the workflow in the conventional and digital impression. The effect of the number of implants on time was also assessed. Satisfaction was assessed through a questionnaire based on seven. The Wilcoxon test used to identify the statistical difference between the groups in terms of time. The Mann-Whitney test was used to analyze the relationship between the time and the number of implants. Fisher's test was used to assess the patient satisfaction (P<.05). RESULTS. The time with DI was shorter than with CI (DI, $\tilde{x}=02:58$; CI, $\tilde{x}=31:48$) (P<.0001). The arches rehabilitated with 3 implants required shorter digital impression time (3: $\tilde{x}=05:36$; 4: $\tilde{x}=09:16$) (P<.0001). Regarding satisfaction, the DI was more comfortable and pain-free than the CI (P<.005). CONCLUSION. Digital impressions required shorter chair time and had higher patient acceptance than conventional impressions.

• 대한산업공학회지
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• 제1권1호
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• pp.99-103
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• 1975

A procedure for the test of independence of the observations and the null distribution are studied for a waiting-time distribution of the number of Bernoulli trials required to obtain a preassigned number of successes under Markov dependence. Selected critical values for the test statistic are tabulated.

• 한국콘텐츠학회논문지
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• 제18권8호
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• pp.27-35
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• 2018

본 연구는 대학생의 취업 소요기간 및 정규직으로의 취업 소요기간에 있어서 개인의 특성, 대학의 특성 및 대학에서의 교육 경험이 어떠한 영향을 미치는지 확인하기 위해 한국교육고용패널(KEEP) 11개년 자료를 분석하였다. 분석 결과, 인문계열 전공자에 비해 사회계열, 교육계열, 공학계열, 의약계열 전공자의 취업소요기간이 짧은 것으로 나타나 전공계열에 따른 취업 소요기간의 차이를 확인하였고, 또한 남성일수록, 수도권 소재 대학 졸업자일수록 취업 소요기간이 길게 나타나는 것을 확인하였다. 본 분석에서 취업 소요기간은 대학 특성 및 대학에서의 경험보다 개인 특성으로 더 많이 설명할 수 있음을 확인하였고, 분석 결과를 토대로 전공계열별 차별화된 지원, 학생들의 요구에 맞춘 지원 프로그램의 필요성 등 결론을 도출하였다.

• 한국정보통신학회논문지
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• 제21권11호
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• pp.2022-2028
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• 2017

최근 사물 인터넷 기술의 발달로 인해 사용되는 센서의 수가 늘어남에 따라 센서의 전원 부족 및 사적인 정보의 유출이 심각한 문제로 여겨지고 있다. 이러한 문제들을 해결하기 위해 외부의 RF 신호로부터 전력을 수집하는 RF 에너지 하베스팅과 물리계층 보안 기술의 중요성이 점차 커지고 있다. 본 논문에서는 소스가 전송하는 신호로부터 에너지 하베스팅이 가능한 릴레이가 존재하는 무선 네트워크에서 정보 보안을 향상시키기 위한 시간 전환 기반 네트워크 아날로그 코딩 기법을 제안한다. 소스가 전송하는 신호를 도청하려는 도청자가 존재하는 2-hop 릴레이 네트워크를 모델링하고, 수학적 분석을 통해 최소 요구 보안 용량을 최대화 할 수 있는 최적의 시간 전환 비율을 찾았다. 다양한 환경에서 시뮬레이션을 통해 제안 방안이 기존 방안에 비해 최소 요구 보안 용량을 개선함을 보인다.

• 복식
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• 제53권7호
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• pp.139-146
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• 2003

This study was aimed at analyzing a characteristics of the sewing machines and analyzing the effective sewing time in the garment manufacture process, therefore to obtain the basic data concerned with the sewing. operation standardization. The two methods were experimented. First, two garment factories established in Seoul and Geonggi province were randomly selected for the analyzing the sewing speed of the sewing operator for the optimized sewing speed using the equipment of Digital Tachometer HT4100. Second, five garment factories established in Seoul and Geonggi province were randomly selected to analyze the required time data to reach the fixed sewing speed using the lock stitch sewing machine which was used in the sewing factories. The results are divided into 3 categories as follows; 1) Survey results for the optimized sewing speed : The sewing operations of 10~20 cm range were most frequently selected in seam constructions in Korean sewing factories, and the sewing speed of 2,500 R.P.M was most used; 2) Required time to reach the fixed sewing speed using the lock stitch sewing machine : The mean of required time to the fixed sewing speed of 2.500 R.P.M was 3.5 second, and the mean of the real-sewing length during the 3.5 second was 43.8 cm ; 3) Analysis of the optimized sewing speed calculated using these results : The optimized sewing speed for the sewing manufacturers of the upward of 43.8 cm was 2,500 R.P.M. and for the sewing manufacturers of the below of 42.2 cm, the optimized sewing speed was 2.450 R.P.M.

• 무역상무연구
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• 제41권
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• pp.103-132
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• 2009

In international sales of goods, the buyer must pay the price for the goods as required by the contract and CISG, The buyer's this obligation includes taking such steps and complying with such formalities as may be required under the contract, which includes providing the seller with relevant letter of credit through the issuing bank. Where the parties have not stipulated the time limit within which the credit should be opened, but there is an agreed date or period for shipment, the time limit for the L/C opening should be calculated back from the agreed date of shipment or the first date of shipment, while, in addition, the buyer should open the L/C sufficiently earlier than the shipment date in order for the seller to be able to know the L/C's opening before beginning to ship the goods. The L/C provided the buyer should conform to the contract of sale. Therefore, for example, when an unconfirmed L/C is provided violating the agreement or the L/C opened states that, under a FOB contract, a "freght prepaid" bill of lading shall be presented as a required document of the L/C, the buyer has failed to perform his obligation. If the buyer fails to perform his obligations to provide the letter of credit, the seller may require the buyer to perform that obligation; may fix an additional period of time of reasonable length for performance of the obligation; or, the seller may declare the contract avoided, if the failure amounts to a fundamental breach of contract, or if the buyer does not, within the additional period of time fixed by the seller, perform the obligation; and the seller claim damages. However, when a relevant L/C has been issued for the seller, as a rule, he cannot ask directly for the buyer to pay the price before avail himself of the L/C first.

• Journal of Biosystems Engineering
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• 제26권4호
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• pp.391-398
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• 2001

A robot system for clone replication and gridding, which is a preliminary state of the genome research, was developed and evaluated its performance. This gridding robot system consisted of 1) a gridding heat that replicated the clone, 2) a manipulator, as a part of body of robot, which transferred the gridding head along x-, y-, z-axis, 3) a well plate arranging board, 4) a sterilization unit, and 5) a control unit. Performance of the system was evaluated with 1) repeatability of the robot system, 2) clone replication efficiency, 3) time requirement of the replication, and 4) sterilization efficiency. The repeatability error of the robot system showed 0.219 mm and 0.094 mm in the direction of x- and y-axis, respectively. The success rate of the clone replication with the gridding head was 100% on the membrane filter. The time required for the replication was four minutes and fifty-five seconds from the four 96 well plates to a 384 well plate meanwhile the required time with well experienced hand labor was three minutes thirty-five seconds. The gridding operation of clone could not be done by hand labor and the required time with robot system for the gridding on the membrance filter with the control program 5$\times$5: 1 copy and 384 gridding pins was twenty minutes and twenty-five seconds. The efficiency of the sterilization was considered to be satisfactory since no growth of fungi was found around the area of replication in the membrane filter.

• Molecules and Cells
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• 제41권7호
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• pp.676-683
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• 2018

Cilia are highly specialized antennae-like organelles that extend from the cell surface and act as cell signaling hubs. Intraflagellar transport (IFT) is a specialized form of intracellular protein trafficking that is required for the assembly and maintenance of cilia. Because cilia are so important, mutations in several IFT components lead to human disease. Thus, clarifying the molecular functions of the IFT proteins is a high priority in cilia biology. Live imaging in various species and cellular preparations has proven to be an important technique in both the discovery of IFT and the mechanisms by which it functions. Live imaging of Drosophila cilia, however, has not yet been reported. Here, we have visualized the movement of IFT in Drosophila cilia using time-lapse live imaging for the first time. We found that NOMPB-GFP (IFT88) moves according to distinct parameters depending on the ciliary segment. NOMPB-GFP moves at a similar speed in proximal and distal cilia toward the tip (${\sim}0.45{\mu}m/s$). As it returns to the ciliary base, however, NOMPB-GFP moves at ${\sim}0.12{\mu}m/s$ in distal cilia, accelerating to ${\sim}0.70{\mu}m/s$ in proximal cilia. Furthermore, while live imaging NOMPB-GFP, we observed one of the IFT proteins required for retrograde movement, Oseg4 (WDR35), is also required for anterograde movement in distal cilia. We anticipate our time-lapse live imaging analysis technique in Drosophila cilia will be a good starting point for a more sophisticated analysis of IFT and its molecular mechanisms.