6,134 research outputs found
Locally Adaptive Products for Genuine Spherical Harmonic Lighting
Precomputed radiance transfer techniques have been broadly used for supporting complex illumination effects
on diffuse and glossy objects. Although working with the wavelet domain is efficient in handling all-frequency
illumination, the spherical harmonics domain is more convenient for interactively changing lights and views on
the fly due to the rotational invariant nature of the spherical harmonic domain. For interactive lighting, however,
the number of coefficients must be limited and the high orders of coefficients have to be eliminated. Therefore
spherical harmonic lighting has been preferred and practiced only for interactive soft-diffuse lighting. In this
paper, we propose a simple but practical filtering solution using locally adaptive products of high-order harmonic
coefficients within the genuine spherical harmonic lighting framework. Our approach works out on the fly in two
folds. We first conduct multi-level filtering on vertices in order to determine regions of interests, where the high
orders of harmonics are necessary for high frequency lighting. The initially determined regions of interests are
then refined through filling in the incomplete regions by traveling the neighboring vertices. Even not relying on
graphics hardware, the proposed method allows to compute high order products of spherical harmonic lighting for
both diffuse and specular lighting
Data Envelopment Analysis for establishing the financial benchmark of Korean hotels
In the wake of catastrophic natural disasters and rising threats of terrorism, the hotel industry has seen a decline in revenue and an increase in competition. To avoid a downward spiral, the hotel industry needs to develop more competitive business strategies in order to make its operations lean and robust. These strategies may include: customer relationship management, yield management, niche marketing and continuous improvement of financial health. The success of these strategies hinges on the ability of hotel managers to assess the financial efficiency of their hotel in comparison to competition. In an effort to help hotel management enhance its financial efficiency in an increasingly competitive hotel industry, this paper proposes a Data Envelopment Analysis (DEA), which develops a meaningful set of benchmarks that will dictate best practices and form a successful hotel business model. Using the examples of 39 international and regional hotels in Korea, this paper illustrates the usefulness of DEA for the continuous improvement of hotel business practice
A Case Report of Painless Moving Toes Syndrome
This is the first report of a case of painless moving toes syndrome with radiculopathy. The patient presented with bilateral painless moving toes and unilateral subclinical sacral (S1) radiculopathy. Bilateral movements with the unilateral lesion, and fluctuation with postural changes and distant muscle contraction suggest that the underlying pathomechanism was a central reorganization in the spinal level
Influence of the waist diameters on transmission characteristics and strain sensitivity of microtapered long-period fiber gratings
Transmission characteristics of microtapered long-period fiber gratings (MTLPGs) and their strain and temperature sensitivities with variations in the waist diameters are investigated theoretically and experimentally. Transmission characteristics of MTLPGs strongly depend on the waist diameter of the tapered optical fiber (TOF) because of the modification of the effective index difference between the core and the cladding modes. Based on the photoelastic effect, the resonant wavelengths of MTLPGs with variations in strain shift to shorter wavelengths. The strain sensitivity of the MTLPG with a waist diameter of 25 μm is improved by a factor of 20 compared with that of a 125 μm long-period fiber grating. The temperature sensitivities of MTLPGs are also enhanced by reducing the waist diameter of the TOF
Quantitative agreement of Dzyaloshinskii-Moriya interactions for domain-wall motion and spin-wave propagation
The magnetic exchange interaction is the one of the key factors governing the
basic characteristics of magnetic systems. Unlike the symmetric nature of the
Heisenberg exchange interaction, the interfacial Dzyaloshinskii-Moriya
interaction (DMI) generates an antisymmetric exchange interaction which offers
challenging opportunities in spintronics with intriguing antisymmetric
phenomena. The role of the DMI, however, is still being debated, largely
because distinct strengths of DMI have been measured for different magnetic
objects, particularly chiral magnetic domain walls (DWs) and non-reciprocal
spin waves (SWs). In this paper, we show that, after careful data analysis,
both the DWs and SWs experience the same strength of DMI. This was confirmed by
spin-torque efficiency measurement for the DWs, and Brillouin light scattering
measurement for the SWs. This observation, therefore, indicates the unique role
of the DMI on the magnetic DW and SW dynamics and also guarantees the
compatibility of several DMI-measurement schemes recently proposed.Comment: 24 pages, 5 figure
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