An optimal auction with moral hazard

Abstract We consider a single-item, independent private value auction environment with two bidders: the leader, who knows his valuation, and the follower, who exerts an effort that affects the probability distribution of his valuation, which he then learns. We provide sufficient conditions under which an ex-post efficient revenue-maximizing auction solicits bids sequentially and partially discloses the leader’s bid to the follower, thereby influencing the follower’s effort. This disclosure rule, which is novel, is non-monotone and prescribes sometimes revealing only a pair to which the leader’s bid belongs and sometimes revealing the bid itself. The induced effort distortion relative to the first-best is discussed

Dynamic project selection

We study a normative model of an internal capital market, used by a company to choose between its two divisions’ pet projects. Each project’s value is initially unknown to all but can be dynamically learned by the corresponding division. Learning can be suspended or resumed at any time and is costly. We characterize an internal capital market that maximizes the company’s expected cash flow. This market has indicative bidding by the two divisions, followed by a spell of learning and then firm bidding, which occurs at an endogenous deadline or as soon as either division requests it

A Tight Connection Between Direct and Indirect Detection of Dark Matter through Higgs Portal Couplings to a Hidden Sector

We present a hidden Abelian extension of the Standard Model including a complex scalar as a dark matter candidate and a light scalar acting as a long range force carrier between dark matter particles. The Sommerfeld enhanced annihilation cross-section of the dark matter explains the observed cosmic ray excesses. The light scalar field also gives rise to potentially large cross-sections of dark matter on nucleon, therefore providing an interesting way to probe this model simultaneously at direct and indirect dark matter search experiments. We constrain the parameter-space of the model by taking into account CDMS-II exclusion limit as well as PAMELA and FermiLAT data.Comment: 15 pages, 7 figures. Added discussions on tuning and inverse Compton scattering constraints. References added and updated. Matches the published versio

Analisis Dan Simulasi Video Watermarking Menggunakan Metode Dual Tree Complex Wavelet Transform (DT-CWT) Dan Singular Value Decomposition (SVD)

Video piracy is the act of obtaining, copying, and selling or distributing videos that already had the copyright without the consent of the copyright owner. Watermarking is a process which embeds an additional information in the host video signal so that the embedded watermark cannot be seen and difficult to be erased or altered. Video watermarking in this journal used a mp4 format video and two different watermark images. Host video frames are divided into two equal lots, some of the frames are embedded by watermark image 1, and the others are embedded by watermark images 2. The methods used are Dual-Tree Complex Wavelet Transform (DTCWT) and Singular Value Decomposition (SVD). The two watermarks are embedded and extracted in each subband at a depth level 1 to level 4 DTCWT - SVD with the aim of seeking the best subband and the best level for embedding and extracting. In the extraction testing, watermarked video is given several attacks before extraction process. Based on the MOS and PSNR value the DTCWT-SVD level for embedding process is level 4, and based on the MOS and MSE value, the best extraction images are produced from the level 3. The best subband for embedding watermark are the subbands with three parts such as {1,5}{1,1}{1,2} and {1,5}{1,2}{1,2}

An experimental study on the evolution of modal damping with damage in carbon fiber laminates

Many of the techniques developed to assess structural damage are based on experimental modal analysis. This paper presents a study to extend the current understanding of how increasing damage in a carbon fiber reinforced plastic affects the modal damping factor of a laminated structure. Damage is introduced and quantified in terms of the dissipated energy. It is shown that there is a tendency for the overall damping to increase whereas there is a tendency for the overall stiffness to decrease. While these results are not novel, the former is quite relevant, since the authors are not aware of many other experimental studies on the evolution of the modal damping factor with damage in carbon fiber reinforced plastic. At the same time, a modal-based damage location technique that combines both the natural frequencies and the modal damping factors as damage sensitive features is discussed. The hypothesis that different damage morphologies on composite materials have different contributions to the damage features is drawn. The methods are illustrated with both numerical and experimental examples. One of the problems observed is that, although damping is consistently found to increase globally with damage, the determination of the individual changes of the modal damping factors is still very uncertain. This may be due to concurrent damage types being present at the same time, but most certainly due to uncertainties involved in the identification of the modal damping factors

Transparansi Arsitektur dalam Proses Rancang Terminal Kampung Rambutan

Terminal Kampung Rambutan sebagai salah satu terminal besar di Jakarta telah dikenal tidak ramah terhadap pengunjungnya, karena ketidakteraturan penataan sirkulasi, kepadatan pengunjung dan kesan kumuh yang ditimbulkan. Lokasi terminal berada berdekatan dengan dua jalur tol, menghubungkan antara ibukota dan kota di sekitarnya, sehingga terminal ini haruslah mempunyai fasilitas lengkap yang dapat membuat pengunjung merasa nyaman dan aman. Dari pokok utama permasalahan di Terminal Kampung Rambutan yaitu sirkulasi dan kepadatan pengunjung yang menimbulkan penghalang pandangan maka tema Transparan dibutuhkan sebagai pendekatan rancangan metafora teraga (tangible metaphor). Aplikasi tema transparan pada rancangan ini terlihat pada tampilan eksterior, interior, bahan material, bentuk geometri, dan ekspresi struktur ekspos yang digunakan

A new viable region of the inert doublet model

The inert doublet model, a minimal extension of the Standard Model by a second Higgs doublet, is one of the simplest and most attractive scenarios that can explain the dark matter. In this paper, we demonstrate the existence of a new viable region of the inert doublet model featuring dark matter masses between Mw and about 160 GeV. Along this previously overlooked region of the parameter space, the correct relic density is obtained thanks to cancellations between different diagrams contributing to dark matter annihilation into gauge bosons (W+W- and ZZ). First, we explain how these cancellations come about and show several examples illustrating the effect of the parameters of the model on the cancellations themselves and on the predicted relic density. Then, we perform a full scan of the new viable region and analyze it in detail by projecting it onto several two-dimensional planes. Finally, the prospects for the direct and the indirect detection of inert Higgs dark matter within this new viable region are studied. We find that present direct detection bounds already rule out a fraction of the new parameter space and that future direct detection experiments, such as Xenon100, will easily probe the remaining part in its entirety.Comment: 27 pages, 16 figure