• International conference on construction engineering and project management
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• 2011.02a
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• pp.629-635
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• 2011

Retentions are generally considered to be intended to act as a powerful tool to incentivize contractors/subcontractors to remedy defective work in cases of non-performance. This study attempts to establish the extent to which retentions can be used for this purpose by investigating case law connected with insurance and defective work. One of the significant questions is whether retentions are sufficient to deal with construction defects or value of retentions in the rectification of defects is illusory. The cost to repair a defect may vary depending on a number of components including type, cause, magnitude and the construction stage at which the defect occurs. It is expected that a review of existing cases on defective workmanship will provide an insight on the issues and whether retentions are effective in their intended function. In order to establish their functionality, the study described in this paper investigated 6 construction insurance cases to identify the critical issues and the causes of dispute. It was found that the nature and the cause of defects were different in each case. It was also established that certain defect types not covered by insurance may be covered by retentions - potentially one of the key uses of a retention strategy. It is expected that the findings will assist in forming a view on the quantum of money that may be required paving the way for a first time understanding on a rational basis for setting up retention regime.

• Korean Journal of Construction Engineering and Management
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• v.13 no.6
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• pp.63-70
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• 2012

The apartment house taking most part of our housing types was facing the limit of consumption from the housing supply-oriented policy in the past of rapid urbanization resulting in being transferred to the housing supply-oriented one. Accordingly the requirement for housing quality by customers is diversified varied, in order to meet this the effective and systematic quality control for preventing the defects from the stage of building is required. In this study for the effective and systematic quality management for defects of apartment house analysis on the frequencies and loss expenses from defective maintenance regarding examples of apartment houses having been moved in within five years recently, and the survey on their dwellers' consciousness were made, and the table for quantified apartment house defective risk.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1995.04a
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• pp.77-77
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• 1995

Human immunodeficiency virus type 1 (HIV-1) contains several nonstructural genes which are required for the viral replication and disease pathogenesis. Among them, tat and nef genes encode an essential transactivator of HIV-1 LTR and a pluripotent protein which seems to be essential for the in vivo but not in vitro viral replication, respectively. We constructed two tat and n of defective HIV-1 and tested for their ability to replicate in several T cells. The defective viruses did not replicate in CD4$\^$+/ T cells, but rescued in the recombinant Jurkat-tat cell which also contains tat gene. The replication of tat and nef defective HIV-1 which expresses chloramphenicol acetyltransferase(CAT) gene was easily detected by a sensitive CAT assay. No revertant was identified during the passages of the mutant viruses for more than two months in Jurkat-tat cells. tat and n of defective HIV-1 could be used instead of wild type viruse for several purposes such as inhibitor screening and development of attenuated AIDS vaccine.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2007.11a
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• pp.718-721
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• 2007

Construction schedule plays a key role in project management due to its influence on the project success. Thus, it is important to identify factors affecting construction delay. The major objective of this study is to identify and evaluate factors affecting construction delay in apartment projects in Vietnam. The findings confirmed that financial difficulties of owners and contractors, contractors without adequate experience, non-available materials on time, slow site clearance, inappropriate construction methods, defective works and reworks, and lack of capable owners/project managers are the major causes of delay in apartment projects.

• Proceedings of the Microbiological Society of Korea Conference
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• 2005.05a
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• pp.225.4-225
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• 2005

• Proceedings of the Korean Institute of Building Construction Conference
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• 2022.11a
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• pp.131-132
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• 2022

The type and proportion of construction work varies depending on the stage of progress, and the frequency of inspection and defect occurrences are different. If it is determined to be defective after the inspection, a delay may occur, and additional manpower and resources are required. Therefore, it is necessary to prevent these risks by classifying, deriving, and managing key management woks according to the progress. This study aims to contribute to the efficiency of the supervisor's inspection work by identifying the types of construction that should be managed intensively for each construction progress and deriving the time when defects occur frequently in each construction type.

• Journal of Microbiology
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• v.33 no.2
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• pp.142-145
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• 1995

The pumb gene encoding a basic amino acid transport protein in Neurospora crassa could be cloned by using a mutant strain defective in pmb gene as a host strain, using a negative selection on the media containing amino acid analogue canavanine. To select positive transformants of the genes for cloning, an auxotrophic marker (his-2) was added to a pmb mutant strain by mating ; a triple mutant (pmn : pmb : his-2) was constructued by crossing a strain defective in basic amino acid transport system (# 1683-bat um 535 "A") to a double mutant strain defective in neutral amino acid transport and histidine production (mitrol : his-2 "a"). Crossing was performed on synthetic crossing (SC) media containing histidine. The pmn : pmb and pmn :pmb : his-2 strains were selected among the progeny colonies from crosses on plates containing 5- .mu.g/ml para-fluoro-phenylalanine (PFPA), 200 .mu.g/ml canavanine, and 500 .mu.g/ml histidine. The selected colonies were cultured on minimal media with or without histidine for discarding pmn : pmb strain, because the pmn : pmb : his -2 strain grows only on histidine containing media. The pmn :pmb : his-2 strain selected can be used as a host strain for the cloning of the pmb and the pmn genes from a Neurospora genomic library by means of positive selections.

• BMB Reports
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• v.36 no.3
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• pp.275-281
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• 2003

An E1B-defective adenovirus, named r2/Ad carrying the neo expression cassette, was constructed by homologous recombination. The construction, selection (using neomycin as a selective marker), and propagation of the recombinant virus was performed in human embryonic kidney 293 cells (HEK 293). An in vitro study demonstrated that this recombinant virus has the ability to replicate in and lyse some p53-deficient human tumor cells such as human glioma tumor cells (U251) and human bladder cells (EJ), but not in some cells with functional p53, such as human adenocarcinoma cells (A549) and human fibroblast cells (MRC-5). Also, based on the cytopathic effect (CPE), it was demonstrated, under identical conditions, that the U251 cells were more sensitive to r2/Ad replication than the EJ cells. In this paper, we report that r2/Ad could be very useful in studying the in vitro selective replication of E1B-defective adenovirus and has great potential in cancer gene therapy.

• Journal of the Korea Institute of Building Construction
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• v.22 no.2
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• pp.171-182
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• 2022

The regular assessment of a building is important to understand structural safety and latent risk in the early stages of building life cycle. However, methods of traditional assessment are subjective, atypical, labor-intensive, and time-consuming and as such the reliability of these results has been questioned. This study proposed a method to bring accurate results using a 3D laser scanner and integrate them in Building Information Modeling (BIM) to visualize defective condition. The specific process for this study was as follows: (1) semi-automated data acquisition using 3D laser scanner and python script, (2) scan-to-BIM process, (3) integrating and visualizing defective conditions data using dynamo. The method proposed in this study improved efficiency and productivity in a building assessment through omitting the additional process of measurement and documentation. The visualized 3D model allows building facility managers to make more effective decisions. Ultimately, this is expected to improve the efficiency of building maintenance works.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• autumn
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• pp.46-53
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• 2002

Although Public Construction Works in Korea have been executed according to Government Contract Act, and nature of contract is very complicated. So it is difficult to define liability for the defects. Therefore the studies on the defective performance and contractor's defects liability were remained one of the non-cultivated virgin land. As a result, contract privy waive the right to claim or generally resolve the problems. Therefore domestic and overseas liability for the defects was investigated and liability for the defects, under and after construction, on the defective performance and defects, was analysed. With a literature research, contractor's defect liability was systematically analyzed, problems were defined and resolution of the problem were suggested item by item in this study.