• International conference on construction engineering and project management
• /
• 2011.02a
• /
• pp.182-186
• /
• 2011

Early cost estimates are important to decision-making for a construction project. Moreover, the possibility of reducing the project cost is getting less as the project is progressed. Case-based reasoning (CBR), which can be viewed as an effective method for early cost estimating, is widely utilized recently. Early cost estimates using CBR have advantages over the traditional ones as they produce reasonable outputs and self-studying is possible by simply adding new cases. Case-based reasoning is composed of a cycle of retrieve, reuse, revise, and retain process. However, in the majority of research cases, they are focused on how to retrieve the similar cases, instead of revising the cases which is expected to increase accuracy results of cost estimation. This research suggests a method of revising retrieved similar cases in a GA-CBR cost model which is widely studied and utilized for early cost estimating recently. To validate the proposed method, case study is conducted based on Korean public apartment projects.

• Archives of Plastic Surgery
• /
• v.47 no.1
• /
• pp.97-101
• /
• 2020

Although the success rate of deep inferior epigastric perforator (DIEP) flaps has increased, late flap failures still occur and have a low salvage rate. The present article describes a case of salvage of a case of late flap failure using the pedicle vein as a vein graft source. A 50-yearold woman underwent a bilateral DIEP free flap procedure. On postoperative day 6, she experienced flap compromise and underwent emergency flap revision. In the flap revision, flap venous drainage and the superficial inferior epigastric vein were completely obstructed. A Fogarty catheter was used to remove a thrombus from the completely obstructed pedicle vein, and this pedicle vein was used as a graft source and was ligated in retrograde fashion to the flap vein stump. After injection of urokinase into the arterial branch, venous flow to the flap was restored. At a 6-month follow-up visit in the outpatient clinic, only partial fat necrosis at the flap was noted. By dissecting various perforators in the initial operation, decisions regarding immediate revision can be made with more confidence. Additionally, the combined procedures performed in this case may be helpful even for practitioners treating cases of late flap compromise.

• Transactions of the Korean Society for Noise and Vibration Engineering
• /
• v.11 no.9
• /
• pp.414-421
• /
• 2001

If a machine has some faults, we can detect them using vibration or noise signals. However some maintenance engineers who don\`t have export knowledge, need the help of vibration experts for diagnosing the machine. In this paper a case based reasoning (CBR) system is developed which is able to manipulate the past experiences of vibration diagnosis experts. In the CBR system, the maintenance engineers can retrieve the information form previous cases which are most similar to new problem s that they can solve new problem using solutions form the previous cases. In this paper, a new case retrieval method of CBR system using Petri net is proposed and also applied to diagnosis for electric motors as a practical problem.

• Journal of the Korea institute for structural maintenance and inspection
• /
• v.4 no.4
• /
• pp.171-180
• /
• 2000

This study aims to present a more reasonable control value than the exiting one by comparing and analyzing control values and field instrumentation values of the whole excavation depth of the four case sites using geometric averaging as a statistical method. The range of the study is confined to three things: (1) the axial force of the braced excavation walls among a variety of items prescribed in the control values by stress deformation of walls and adjacent structures; (2) by approximation of the allowable and design value; (3) and by safety factor. As a res it is desirable to revise "(Long term allowable stress + Short term allowable stress)/2 ~ Short term allowable stress," presented in the present control values by stress deformation of walls and adjacent structures, to "(Long term allowable stress + Short term allowable stress)/5 ~ (Short term allowable stress)/3." The result also shows that since there is a difference of about 3.5%, it is not necessary to revise 70, 90, and 100 percent of LEVEL I, II, and III, prescribed in the control values by the allowable and design value approximation. In addition, modifying the control value by the safety factor, now 1.07, is unnecessary, although it varies little difference from the present value.

• Journal of the Korean Institute of Landscape Architecture
• /
• v.41 no.1
• /
• pp.60-70
• /
• 2013

This study focused on analyzing classification system, technique methods, quality levels of periodic amendment characteristics in planting of standard specification. Through analyzing the above and comparing with foreign case study, this study suggests the improvement directions. The results improvement directions are as follows. 1. Many kinds of new construction were set up through the amendments of Landscape Standard Specification, but there are still needs to combine some construction categories because of mismatches between upper and lower categories. 2. Although the Landscape Standard Specification was revised to be more concrete, the contents there remains an ambiguous expression. So, standard specification is needed to revise a depth of earth ball or strength of support materials and quantify collect period of topsoil and application time. In addition, standards about following supervisor's instruction should be more detailed or deleted. 3. The standard specification has not been specified despite enactment and amendments reflecting the periodical paradigm and the needs of users, so it is still needed to revise. In addition, quality levels, planting periods, size of earth ball and performance criteria of tree materials are needed to revise. Each specific classification and construction methods were made by amendments of standard specification, but some standards are not clear and concrete. Therefore, the standard specification is needed to revise the classification system, technique methods, and problem deduction of quality levels and proposal of improvement. This study will be reference material when Landscape Standard Specification is revised.

• Journal of Information Technology Services
• /
• v.2 no.2
• /
• pp.39-51
• /
• 2003

The Internet affects all economic activities. Physical world business must either adopt new digital strategies, launch new digital business to complement their physical world models, or be forced to completely revise their strategies. The purpose of this paper is to provide a framework that organizes the managerial decision-making process to assist managers in crafting and implementing e-business strategy. We applied the methodology to the case of KNK Educational Institute to explain the process. Core competence of KNK JUNIOR is researched according to our suggested methodology and activities and roles of KNK JUNIOR have been arranged.

• The Transactions of the Korean Institute of Electrical Engineers A
• /
• v.52 no.1
• /
• pp.50-57
• /
• 2003

In this paper, the protective relay setting rules of Korean electric power system are studied by analysis of errors to be considered. An accurate operation of protective relays with accurate settings are important in power system reliability. The setting rules are used from the first establishment in 1982 and revision in 1990 Therefore, it needs revise and analysis of the setting rules because of environmental changes such as voltage raise or applied new technology of power system. Two major setting rules are studied. One is the rule for Zones of distance relay for transmission lines. The other is the one of differential current in a differential relay for power transformers. The range of errors in the setting rules accepted in the field experience is studied in simulation of case study. Also some guide lines for the range of errors in the setting rules are presented from the case study using Matlab simulation.

• Journal of Korean Society of Rural Planning
• /
• v.15 no.3
• /
• pp.81-87
• /
• 2009

It may be said that a farmer's crisis deepens from the number of farm households and a trend of the number of cultivated land of the farmer attracting attention for the most fundamental numerical value of the Census of Agriculture 2005. A rate of decline of number of farm households seems to have been stopped, but expansion lasts a number of farm households rate of decline. I can, so to speak, watch weakening of flatland area and luck of mountainous areas and a situation to say if I look in that according to classification agricultural area. I can nominate the effect of a direct payment system for farmers in hilly and mountainous areas enforced in 2000 for the background. It is located in case of the policy introduced preceding it while the rural community and the community including the urban area being paid attention as the last resort of a regional reproduction now. In particular, the character as the village activation subsidy has been strengthened in case of the 2nd stage institutional revise.

• Journal of Korean Elementary Science Education
• /
• v.30 no.3
• /
• pp.353-366
• /
• 2011

An alternative vision for science inquiry that appears to be important and challenging is model-based inquiry in which students generate, evaluate and revise their explanatory model. Pre-service teachers should be given opportunities to develop and use their mechanistic explanatory models in order to participate in the practice of science and to have a sound understanding of science. With this view, this study described a case of pre-service elementary teachers' scientific modeling in magnetism. The aims of this study were to explore difficulties preservice elementary teachers encountered while they engaged in a model-based inquiry, and to examine how their understandings of the nature of scientific models changed after the model-based inquiry. The data analysis revealed that the pre-service teachers had difficulties in drawing and writing their own thinking because they had little experience of expressing their own science ideas. When asked to predict what would happen, they could not understand what it meant to make a prediction "based on their model". They did not know how to use or consider their model in making a prediction. At the end of the model-based inquiry they reached a final consensus of a best model. However, they were very anxious about whether the model was the "correct" answer. With respect to the nature of scientific models, almost all of the pre-service teachers initially viewed models only as a communication tool among scientists or students and teachers to help understand others' ideas. After the model-based inquiry, however, many of them understood that they could create, test, and revise their "own" models "by themselves". They also realized the key aspects of scientific models that a model can be changed as evidence is accumulated and a model is a knowledge production tool as well as a communication tool. The results indicated that pre-service elementary teachers' understandings of the nature of scientific models and their previous school science experiences could affect their performance on a model-based inquiry, and their experience of scientific modeling could help them enhance their understandings of the nature of scientific models.

• Journal of Intelligence and Information Systems
• /
• v.9 no.1
• /
• pp.23-51
• /
• 2003

With the recent expansion of internet shopping mall, the importance of intelligent products recommendation agents has been increasing. for the products recommendation, This paper propose case-based reasoning approach, and developed a case-based bundle products recommendation system which can recommend a set of sea food used in family events. To apply CBR approach to the bundle products recommendation, it requires the following 4R steps : \circled1 Retrieval, \circled2 Reuse, \circled3 Revise, \circled4 Retain. To retrieve similar cases from the case-base efficiently, case representation scheme is most important. This paper used OW(Object Modeling Technique) to represent bundle products recommendation cases, and developed a similarity measure method to search similar cases. To measure similarity, we used weight-sum approach basically. Especially This paper propose the meaning and uses of taxonomies for representing case features.