• International conference on construction engineering and project management
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• 2022.06a
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• pp.67-73
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• 2022

Construction bid documents contain various errors or discrepancies giving rise to uncertainties. The errors/discrepancies/ambiguities in the bid document, if not identified and clarified before the bid, may cause dispute and conflict between the contracting parties. Given the fact that bid document is a major resource in estimating construction costs, inaccurate information in bid document can result in over/under estimating. Thus, any questions from bidders related to the errors in the bid document should be clarified by employers before bid submission. This study aims to examine the pre-bid queries, i.e., pre-bid request for information (RFI), from state DoTs of the United States to investigate error types most frequently encountered in bid documents. For the study, around 200 pre-bids RFI were collected from state DoTs and were classified into several error types (e.g., coordination error, errors in drawings). The analysis of the data showed that errors in bill of quantities is the most frequent error in the bid documents followed by errors in drawing. The study findings addressed uncertainty types in construction bid documents that should be checked during a bid process, and, in a broader sense, it will contribute to advancing the construction management body of knowledge by clarifying and classifying bid risk factors at an early stage of construction projects.

• Journal of Information Technology Applications and Management
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• v.11 no.3
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• pp.23-33
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• 2004

Internet bid systems have been widely used recently. In those systems, the bid price is provided by the seller. When the bid price is set too high compared with the normal price, the successful bid rate can be decreased. Otherwise, when it is set too low based on inaccurate information, it can result in a successful bid with no profit at all. To resolve this problem, we propose an agent that automatically generates bid prices for sellers based on various costing methods such as the high-low point method, the scatter diagram method, and the learning curve method. Through performance experiments, we have found that the number of successful bids with appropriate profit can be increased using the bid pricing agent. Among the costing methods, the learning curve method has shown the best performance. Also, we discuss about how to design and implement the bid pricing agent.

• Journal of the Korean Institute of Intelligent Systems
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• v.14 no.6
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• pp.678-686
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• 2004

This paper presents a new method to securely conduct online sealed-bid auctions with a single auctioneer server The sealed-bid auctions have several vulnerable security problems when they are performed on the Internet. One of such problems is the trust establishment between an auctioneer and bidders who participate in an auction. Several online sealed-bid auction methods have been developed to address this trust problem. The proposed method solves the security problems that would happen in the sealed-bid auction using a blind signature scheme and a contract signature protocol. It prevents the auctioneer from illegally manipulating the bidders' bidding information, repudiating the reception of some bid, manipulating the auction period, and illegally adding or deleting bids. In addition, it keeps the bidders from modifying the bidding information after issuing their bid and doing intentional mistake to invalidate their own bid. The method can be easily implemented using the multiagent architecture.

• Proceedings of the Korea Society of Information Technology Applications Conference
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• 2005.11a
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• pp.247-250
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• 2005

Recently, a concept of bid-rigging is issued in electronic auction. To prevent this attack, Abe-Suzuki proposed firstly receipt-free scheme based on bidding-booth. Chen-Lee-Kim pointed out that Abe-Suzuki's scheme only provides receipt-freeness for losing bidders. Also, they introduced a new receipt-free sealed bid auction scheme using the homomorphic encryption technique. The main participants of their scheme are Auctioneer, Auction Issuer, Bidder and Seller. Bid-rigging can happen by a seller in their scheme. We propose receipt-free sealed-bid auction scheme using a universal re-encryption mixnet. For our receipt-free sealed-bid auction, we use Pseudo ID of a bidder and universal re-encryption technique of Golle et al. Also, our scheme satisfies privacy, correctness, public verifiability, non-reputation, and receipt-freeness.

• Journal of the Korean Data and Information Science Society
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• v.17 no.3
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• pp.795-804
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• 2006

Most internet auction sites open to users the bid history with the ascending order of bid amounts. Whereas eBay.com presents second bid prices, auction.co.kr provides highest bid prices. In this paper, the bidhistory is arranged according to the passage of tim, which can help to understand the situations and trends of bid prices, especially for multiple auctions. This manipulated data can be visualized by using profile plots. The successful bid prices could be estimated based on some prediction models with appropriate prior informations. Both sellers and bidders can be provided useful informations with these statistical analyses, and then fair online auctions in Korea will grow actively and rapidly.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.27 no.2
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• pp.195-202
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• 2009

As the generation and application of spatial information is gradually expanded not only in traditional surveying fields but also a CNS and an ITS recently. The Accuracy and the newest of data grow to be an important element. But digital map is updated with system based tile. So, it is hard to get the newest of data and to be satisfied with user requirements. In this study, management system is developed to manage feature change efficiently using bid informations from NaraJangter which service the bid informations. A construction works with change possibility of feature from bid informations are classified and are made DB. And the DB is used as the feature change forecast informations. Also, It is converted from bid information of text form to positioning informations connected to spatial information data. If this system is made successfully, this system contributes to reduce the cost for the update of digital map and to take the newest date of spatial informations.

• Journal of Internet Computing and Services
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• v.2 no.2
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• pp.95-103
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• 2001

This paper implements the desirable-bid price type bidding agent system that enables internet bidding between buyer and sellers efficiently in real Time. The agent system controls the bid-limit to approach successful desirable-bid price of a buyer. to reduce unsuccessful bid rate using fuzzy-based bid-limit inference method.

• International conference on construction engineering and project management
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• 2022.06a
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• pp.11-17
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• 2022

Design-bid-build (DBB) is the most common project delivery method among highway projects. State Highway Agencies (SHAs) usually apply a low-bid approach to select contractors for their DBB projects. In this approach, the Federal Highway Agency suggests SHAs heighten contractors' competition to lower bid prices. However, these attempts may become ineffective due to collusive bidding arrangements among certain contractors. One common strategy is the rotation of winning bidders of a group of contractors who bid on many of the same projects. These arrangements may also be specific to a particular region or vary in time. Despite the practices' adverse effects on bidding outcomes, an effective model to detect red-flag bidding patterns is lacking. This study fills the gap by proposing a novel framework that utilizes pattern mining techniques and statistical tests for unusual pattern detection. A case study with historical data from an SHA is conducted to illustrate the proposed framework.

• The Journal of Society for e-Business Studies
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• v.7 no.2
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• pp.55-68
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• 2002

Internet group buying systems have been widely used recently. In those systems, because the reserve price is provided by the buyer, the success rate can be decreased if the reserve price is set too low compared with the normal price. Otherwise, an unsuitable successful bid can be made if the reserve price is set too high based on inaccurate information. Likewise, the seller's providing too high a bid price can deteriorate his/her own successful bid rate, whereas a successful bid with too low a price may make no profit in the sale. Therefore, pricing agents that recommend adequate prices based on the past buying and selling history data can be helpful. In this paper, we propose two kinds of agents. One suggests reserve prices to buyers based on the past buying history database of the system. The other recommends bid prices to a seller based on the past bidding history data of the company using the cost accounting theory. Through performance experiments, we show that the successful bid rate can increase by preventing buyers from making unreasonable reserve prices. Also, we show that, for the seller, the rate of successful bids with appropriate profits can increase. Using the pricing agents, we design and implement an XML-based group buying system.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.12 no.6
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• pp.3-15
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• 2002

In this paper, we propose an efficient and secure sealed-bid auction protocol with two servers, a seller S and a third party A . The proposed scheme uses the idea of the conditional oblivious transfer protocol proposed by Crescenzo-Ostrovskey-Rajagopalan. A server A is not a trusted third party, but is assumed not to collude with a server S. In the proposed auction protocol, barring collusion between A and S, neither party gains any information about the bids, and moreover, the outcome of the auction will be correct. And the computational complexity of our auction protocol is considerably efficient and the communication overhead is similar to that of Naor-Pinkas-Sumner's scheme.