• International conference on construction engineering and project management
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• 2015.10a
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• pp.158-160
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• 2015

Efficient scheduling and resource management are the key factor to reduce construction project budget (e.g., labor cost, equipment cost, material cost, etc.). Resource-based line of balance (LOB) technique has been used to complement the limitations of existing time-driven scheduling techniques (e.g., critical-path method). Optimizing construction alternatives contributes to cost savings while honoring the project deadline. However, existing LOB scheduling is lack of identifying optimal resource combination. This study presents a method which identifies the optimal construction alternatives, hence achieving resource minimization in a repetitive construction by using genetic algorithm (GA). The method provides efficient planning tool that enhances the usability of the system.

• International conference on construction engineering and project management
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• 2015.10a
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• pp.166-168
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• 2015

Line of Balance (LOB) method is suitable to schedule construction projects composed of repetitive activities. Since existing LOB based repetitive project scheduling methods are deterministic, they do not lend themselves to handle uncertainties involved in repetitive construction process. Indeed, existing LOB scheduling dose not handle variability of project performance indicators. In order to bridge the gap between reality and estimation, this study provides a stochastic LOB based scheduling method that allows schedulers for effectively dealing with the uncertainties of a construction project performance. The proposed method retrieves an appropriate probability distribution function (PDF) concerning project completion times, and determines favorable start times of activities. A case study is demonstrated to verify and validate the capability of the proposed method in a repetitive construction project planning.

• Journal of Construction Engineering and Project Management
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• v.3 no.2
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• pp.21-34
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• 2013

Various risk factors affect construction projects. Due to the uncertainties created by risk factors, actual activity durations frequently deviate from the estimated durations in either favorable or adverse direction. For this reason, evaluation of schedule uncertainty is required to make decisions accurately when managing construction projects. In this regard, this paper presents a new computer simulation model - the Repetitive Schedule Risk Analysis Model (RSRAM) - to evaluate unit-based repetitive building project schedules under uncertainty when activity durations and risk factors are correlated. The proposed model utilizes Monte Carlo Simulation and a Critical Path Method based repetitive scheduling procedure. This new procedure concurrently provides the utilization of resources without interruption and the maintenance of network logic through successive units. Furthermore, it enables assigning variable production rates to the activities from one unit to another and any kind of relationship type with or without lag time. Details of the model are described and an example application is presented. The findings show that the model produces realistic results regarding the extent of uncertainty inherent in the schedule.

• International Journal of Internet, Broadcasting and Communication
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• v.12 no.2
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• pp.45-50
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• 2020

A Language model with neural networks commonly trained with likelihood loss. Such that the model can learn the sequence of human text. State-of-the-art results achieved in various language generation tasks, e.g., text summarization, dialogue response generation, and text generation, by utilizing the language model's next token output probabilities. Monotonous and boring outputs are a well-known problem of this model, yet only a few solutions proposed to address this problem. Several decoding techniques proposed to suppress repetitive tokens. Unlikelihood training approached this problem by penalizing candidate tokens probabilities if the tokens already seen in previous steps. While the method successfully showed a less repetitive generated token, the method has a large memory consumption because of the training need a big vocabulary size. We effectively reduced memory footprint by encoding words as sequences of subword units. Finally, we report competitive results with token level unlikelihood training in several automatic evaluations compared to the previous work.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2018.05a
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• pp.41-42
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• 2018

Various methods that crash the project completion time have been studied. Line-of-Balance (LOB) is well accepted as a useful method that enables steady resource utilization without frequent hire-and-fire of resources for a project having repetitive units. Existing studies involved in LOB-CPM focuses on thesis such as resource leveling and optimization in construction scheduling community. However, crashing methods are not arrived at a full maturity in LOB scheduling, because no one handles steady resource utilization while keeping activity-relationships. This paper proposes a method that crashes project completion time by hybridizing concurrent engineering and LOB scheduling without using additional resources.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2015.05a
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• pp.132-133
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• 2015

Efficient scheduling and resource management are the key factor to reduce construction project budget (e.g., labor cost, equipment cost, material cost, etc.). Resource-based line of balance (LOB) technique has been used to complement the limitations of time-driven scheduling techniques (e.g., critical-path method). Optimizing construction alternatives contributes cost savings while honoring the project deadline. However, existing LOB scheduling is lack of identifying optimal resource combination. This study presents a method which identifies the optimal construction alternatives, hence achieving resource minimization in a repetitive construction by using genetic algorithm (GA). The method provides efficient planning tool that enhances the usability of the system.

• International Journal of Oral Biology
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• v.41 no.4
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• pp.243-251
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• 2016

This study was undertaken to achieve a high bleaching efficacy with plasma, through longer application and reparative bleaching processes, by different shade evaluation methods. Extracted human teeth were divided into 6 groups (n=10). All teeth were treated in pairs. Low concentration of 15% carbamide peroxide (CP) was applied, with and without plasma, for 10, 20, and 30-min tooth bleaching, respectively. The bleaching procedure was repeated once daily for four days. The teeth were maintained in a moist environment provided by artificial saliva. The Vitapan Classical shade guide and Commission Internationale de L'Eclairage (CIELAB) color system were collectively used to measure the bleaching efficacy. Color evaluation was statistically analyzed using Student t-test and one-way analysis of variance (ANOVA) complemented by Tukey's test. Combining the plasma with 15% CP showed significantly greater color changes compared to bleaching without plasma (p<0.05). A high bleaching efficacy with plasma is proportional to the repetitive application and the treatment time. A 30-min application with plasma provided the best bleaching. Repetitive bleaching showed lower probability of color relapse of the bleached tooth. The color change by shade guide correlated with the changes in CIELAB color system. A value of 1 color change units (CCU) conversion factor for overall color change (${\Delta}E$) values comparisons was 3.724 values. The two measuring methods provide a more accurate correspondence of color change. The repetitive and longer application for tooth bleaching, combined with plasma, has a strong bleaching effect and produces whiter teeth.

• Journal of the Korean Institute of Rural Architecture
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• v.18 no.4
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• pp.1-8
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• 2016

This study is to investigate the meaning and value of Usonian Automatic House System(UAHS) of Frank Lloyd Wright in his later period, focused on materials, methods, and his thoughts. The results of this study are follows. UAHS was the outcome of moderate cost and prefab house which Wright had successively attempted after the early Prairie period. The construction was simple and comparatively cheap, but subsequent automatics were difficult and expensive to build. Nevertheless, it was sufficiently flexible to support a rather wide range of house designs. Concrete was the inert mass and a plastic material. Wright saw a kind of weaving coming out of it. He also saw a kind of concrete masonry, steel for warp and masonry units for woof in the automatic concrete block. The reinforced bars in hollowed joints of concrete block increased the safety factor and affected the expression of the construction through the stabilization they provided. But they did not give concrete block the capability of structural span. Standardization as the soul of the machine might be seen in UAHS. The concrete blocks were more cheap, lighter, and larger hollowed plain than textile blocks in 1920s. But the variety of pattern and different block types in the UAHS were achieved at some sacrifice of standardization. The repetitive nature of production was compromised for artistic goals. The sense of compromise was not maximized, however, because the units as installed looked far more repetitive than they actually were.

• Tuberculosis and Respiratory Diseases
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• v.67 no.6
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• pp.499-505
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• 2009

Background: Mycobacterial Interspersed Repetitive Units (MIRUs) that are located mainly in intergenic regions dispersed throughout the Mycobacterium tuberculosis genome. The selected MIRU loci, which were composed of a 12-locus set, demonstrated a high power for discrimination of Mycobacterium tuberculosis isolates collected from Kangwon province of Korea. To evaluate its ability to discriminate the M. tuberculosis strains, 45 clinical isolates were genotyped using the methods IS6110 RFLP and MIRU. Methods: All the samples were collected during the period from January 2007 to December 2007 from TB patients, who were residents and registered to a public health center of Kangwon Province in Korea. A total of 45 DNAs were extracted from clinical isolated mycobacterial strains and genotyped using IS6110 RFLP, the MIRU method. Results: We compared the 12-MIRU with IS6110 RFLP in the 45 samples, the 12-locus version offered less discriminatory power (Hunter-Gaston discriminatory index [HGDI]: 0.959 vs 0.998; 57.78% of clustered cases vs 8.89%). Conclusion: This 12-locus MIRU can be useful when additional combinations of other loci for genotyping M. tuberculosis in Korea where the Beijing family strains are dominant.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.2 no.1
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• pp.41-51
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• 2004

The cost-effective reduction of occupational radiation dose (ORD) at a nuclear power plant could not be achieved without going through an extensive analysis of accumulated ORD data of existing plants. Through the data analysis, it is required to identify what are the jobs of repetitive high ORD at the nuclear power plant. In this study, Percentile Rank Sum Method (PRSM) is proposed to identify repetitive high ORD jobs, which is based on non-parametric statistical theory. As a case study, the method is applied to ORD data of maintenance and repair jobs at Kori units 3 and 4 that are pressurized water reactors with 950 MWe capacity and have been operated since 1986 and 1987, respectively in Korea. The results was verified and validated, and PRSM has been demonstrated to be an efficient method of analyzing the data.