• KSII Transactions on Internet and Information Systems (TIIS)
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• 제16권4호
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• pp.1266-1285
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• 2022

Compact E-cash is the first scheme which can withdraw 2^l coins within 𝒪(1) operations and then store them in 𝒪(𝑙) bits. Because of its high efficiency, a lot of research has been carried out on its basis, but no previous research pay attention to the privacy of payees and in some cases, payees have the same privacy requirement as payers. We propose a double-blind compact E-cash scheme, which means that both the payer and the payee can keep anonymous while spending. In our scheme, the payer and the bank cannot determine whether the payees of two different transactions are the same one and connect the payee with transactions related to him, in this way, the privacy of the payee is protected. And our protocols disconnect the received coin from previous transaction, then, the coin can be transferred into an unspent coin which belongs to the payee. The proposed e-cash scheme is secure within y-DDHI and LRSW assumption.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제16권1호
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• pp.319-333
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• 2022

In order to enhance system energy efficiency, bidirectional link resource allocation strategy in GFDM-based multiuser SWIPT systems is proposed. In the downlink channel, each SWIPT user applies power splitting (PS) receiver structure in information decoding (ID) and non-linear energy harvesting (EH). In the uplink channel, information transmission power is originated from the harvested energy. An optimization problem is constructed to maximize weighted sum ID achievable rates in the downlink and uplink channels via bidirectional link power allocation as well as subcarriers and subsymbols scheduling. To solve this non-convex optimization problem, Lagrange duality method, sub-gradient-based method and greedy algorithm are adopted respectively. Simulation results show that the proposed strategy is superior to the fixed subcarrier scheme regardless of the weighting coefficients. It is superior to the heuristic algorithm in larger weighting coefficients scenario.

• Geomechanics and Engineering
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• 제31권6호
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• pp.615-622
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• 2022

In this paper, considering the temperature dependence of material physical parameters as well as the effects of thermal effect and shear deformation, we have conducted an in-depth study on the wave propagation of functionally graded (FG) materials circular plate in thermal environment based on the physical neutral surface concept. The dynamic governing equations of functionally graded plates are established, and the dispersion relation of wave propagation is derived. The influence of different temperature fields on the propagation characteristics of flexural waves in FG circular plates is discussed in detail. It can be found that the phase velocity and group velocity of wave propagation in the plate decrease with the increase of temperature.

• 국제학술발표논문집
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• The 2th International Conference on Construction Engineering and Project Management
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• pp.810-819
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• 2007

Usually the status of a bridge is determined by its structural capability and material strength. Consequently a lot of researchers have studied the failure, the fatigue, and the deterioration of the structure in terms of the structural function of a bridge. However, the overall performance of a bridge may be affected simply by the damage of one of its components. Therefore this study utilized a systematic classification and statistical analysis based on the existing bridge inspection data collected in Taiwan to reach the following goals: (1) assess the performance distribution and deterioration rate for bearing and expansion joint of bridge; (2) find out the right time to do the preventive and essential maintenance for the component of bridge with an empirical method, and to decide what time and which component of a bridge will receive preventive maintenance or regular maintenance.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2009년도 춘계학술발표대회
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• pp.1323-1325
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• 2009

MIH(Multimedia Independent Handover)는 이종망간 연동을 위해 IEEE 802.21 WG에서 진행 중인 기술로서, 이종망간 핸드오버를 지원하기 위해 제안되었다. MIH에서 정의한 시그널 메시지들(LGD : Link Going Down, LD : Link Down)은 이동 단말의 현재 상태를 네트워크에 알려주는 역할을 수행한다. 그 중 LGD는 신호세기가 LGD 임계값 이하일 경우 발생하며 후보 AP 검색 및 최종 후보 AP 선택, 그리고 빠른 핸드오버를 위한 최종 후보 AP와의 선 인증 과정을 거친다. 이 후 LD가 LD 임계값 이하일 경우에 발생하며 이 때 실질적인 핸드오버 과정이 수행된다. 이동단말이 LGD 임계값과 LD 임계값 사이에 위치하는 경우, 즉 이종망 사이의 경합 구간에 위치하여 대기하는 경우에는 Ping-Pong Handover가 발생하며 반복적인 시그널 메시지 교환에 의한 오버헤드가 발생하게 된다. 본 논문은 LGD에서 수행되는 핸드오버 준비과정을 축소하고 대신 LD에서 담당함으로서 경합 구간에 위치한 이동단말에서의 오버헤드를 최소화할 수 있는 방안을 제시한다.

• 국제학술발표논문집
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• The 1th International Conference on Construction Engineering and Project Management
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• pp.587-591
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• 2005

The case of laboratory-acquired SARS Corona virus infection in Taiwan has revealed a number of weaknesses in management, construction, and oversight of laboratories. Also, with the increased demands for bio-safety laboratory, there is an urgent need to develop a uniform and comprehensive guidance for architects and construction engineers in the preparation of design and construction. This research investigates the key elements for designers, engineers, and potential owners in biosafety laboratory design and construction. It defines key elements and determines major relationships and standards that should be adhered to when developing site layout. In addition to layout planning and design guidance of biosafety laboratory, this research also interviews the perspective of architects and survey the state-of-the-art technology in Taiwan. It represents the portraits by site investigation. The purpose of the research is to provide guideline of design and avoid potential future conflict to ensure the critical continuity of functions.

• 국제학술발표논문집
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• The 1th International Conference on Construction Engineering and Project Management
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• pp.996-1001
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• 2005

Today, government is no longer considered the sole provider of public works or services. Public-Private Partnership (PPP) has been recognized as an important approach to solving problems for governments in providing public works and services. However, the joint ownership of public works/services complicates the administration of PPP projects. Particularly, the fact that government may rescue a distressed project and renegotiate with the developer causes serious problems in project procurement and management. This paper aims to study when and how government will rescue a distressed project and what impacts government's rescue behavior has on project procurement and contract management. A game-theory based model for government rescue will be developed. This pilot study, the author hopes, may provide theoretic foundations to practitioners/policy makers for prescribing creative PPP procurement and management policies and for examining the effectiveness of PPP policies.

• 국제학술발표논문집
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• The 1th International Conference on Construction Engineering and Project Management
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• pp.564-568
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• 2005

Recently, Knowledge Management (KM) has been applied to construction industry. Surprising, there is few studies that address the most fundamental problem in KM: people may prefer not to share their knowledge so as to preserve their intellectual or unique values in the organization. Without the premise of each individual's willingness to share knowledge, there will be no valuable input for the IT system and, thus, no knowledge management at all. This paper aims to model the behavioral dynamics of knowledge sharing and to design an incentive system that may facilitate knowledge sharing for construction companies. In this paper, a game-theory based model will be developed, and the framework for designing an incentive system will be proposed according to the model.

• 국제학술발표논문집
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• The 1th International Conference on Construction Engineering and Project Management
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• pp.469-473
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• 2005

Contract design plays a key role in the life cycle of BOT project. All project management activities and operation processes are arranged in consistence with the document of BOT contract which the public sector ensures that the respective roles and responsibilities set out in the contract are fully understood and fulfilled to the contracted performance criteria. With limited theories to deal with some fundamental issues of BOT contract design, we try to collect data from case studies and formulate several practical principles. The conclusions presented in this paper are analyzed from two cases, one is based on an early case in the United Kingdom, and the other based on the Taiwan High Speed Railway case. The purpose of this paper is not about covering all legal issues about BOT contract design, but rather, our work provides common considerations applicable to the contract parties of a broad range of BOT contracts. The results in this paper shall propose some fundamental principles of the BOT contract design.

• 국제학술발표논문집
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• The 1th International Conference on Construction Engineering and Project Management
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• pp.719-724
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• 2005

It has been debating on the performance evaluation of professional construction management (PCM) services since its introduction to Taiwan's construction industry more than a decade ago. Several evaluation systems were proposed by previous researchers. However, there has no comparison study been conducted for the feasibility, effectiveness, and appropriateness of these systems to the performance management (PM) of practical PCM services. This paper is intended for this end to compare the existing PCM performance evaluation systems in Taiwan. A real world design/build (D/B) building project was selected for case study. The result of case study concludes and compares the pro's and con's of the three systems. At the end, it recommends strategies for selecting the most appropriate PCM performance evaluation for PCM services.