Invisible Space Research Articles

Scarlesss Intra-Retroperitoneoscopy in Human and Animal NOTES® Translumenal Cholecystectomy, Appendectomy and GI Anastomosis

Purpose: Natural orifice translumenal endoscopic surgery (NOTES) is a novel concept that provides the potential for performance of incisionless imaging and operations. The method of accessing the abdominal cavity through a natural orifice under endoscopic visualization might offer advantages over open and laparoscopic surgery. The purpose of this study is to develop novel endoscopic technology and procedure to overcome the limitations of intra-abdominal and retroperitoneal imaging and surgery that is used to be invisible. Methods: We performed NOTES intra-retroperitoneoscopy in 2 human cadaver and 12 survival porcine and canine studies. After perforation of the gastric, colonic, and vaginal wall, a flexible double-channel scope was advanced into the peritoneal cavity and retroperitoneal space under endoscope-induced carbon dioxide insufflation. After performing observations and surgical procedures, the wall was closed using a suturing system or endoscopic clips. Results: The endoscope could visualize each objective organ in all 14 attempts. Following liver biopsy or lymph node removal, GI anastomosis or intestinal resection were also accomplished using a standard flexible endoscope without laparoscopic assistance. Animal NOTES cholecyctectomy was completed in 6 transgastric, 2 transcolonic, and 2 transvaginal access. Transgastric intestinal resection was performed in 4 procedures. No acute complications were recorded. The submucosal, intramuscular and retroperitoneal imaging could be allowed histological diagnosis. Human cadaver NOTES transvaginal cholecystectomy and appendectomy were also completed within 90 and 40 minutes without major complications. Conclusions: Our study described the use of translumenal endoscopy to accomplish intra-abdominal surgeries. This could reach to the invisible space using standard modalities. Scarlesss intra- and retroperitoneal imaging of NOTES is technically feasible and safe in either human or animal study. CLINICAL RELEVANCE/APPLICATION: NOTES procedure is enormously advantageous to the patient. This would break the physical barrier between bodily trauma and surgery, representing the revolution in surgery.

Computing return loss for arbitrary scan directions using limited scan codes for infinite phased arrays

Analysing infinite phased array antennas using time domain codes is favourable when looking into wideband solutions. Unfortunately, unit cell-based time domain codes using time shifts between cell boundaries have a disadvantage of only being able to analyse phase shifts corresponding to a beam scanned in the visible space. However, to fully characterise the infinite array antenna it is sometimes necessary to compute the active reflection coefficient for scan directions corresponding to invisible space. Presented is a simple new approach on how to do this. By extending the size of the computational domain, and including more than one element, phase shifts corresponding to invisible space are included.

A novel design of dielectric perfect invisibility devices

The aim of an invisibility device is to guide light around any object put inside, being able to hide objects from sight. In this work, we propose a novel design of dielectric invisibility media based on negative refraction and optical conformal mapping that seems to create perfect invisibility. This design has some advantages and more relaxed constraints compared with already proposed schemes. In particular, it represents an example where the time delay in a dielectric invisibility device is zero. Furthermore, due to the impedance matching of negatively refracting materials, the reflection should be close to zero. These findings strongly indicate that perfect invisibility with optically isotropic materials is possible. Finally, the area of the invisible space is also discussed.

Virtuality in architecture: From perspective representation to augmented reality

Notion of virtuality correlates mainly to visual aspects of space, presuming that basic qualities of physical space can be simulated by graphics, providing not just visual illusion of the third dimension of real space, but psychological involvement and transfer of the spectator into the space of the picture, giving him the sense of the spatial location and presence. Creation of virtual space that could be perceptually sensed and by virtual presence modified and shaped, explored and experienced, is not just result of advanced computer technology, but could be traced through history of spatial representations, that was based mainly in artistic and architectural practice. Architecture, being leading field that synthesize representation, construction and sense of spatial creation, had to be involved in explorations of multidimensional complex network of dynamic informational space, that is revealed in its real and virtual dimension as unique universe. Real-time experience in virtual space allow access in the alternative dimension to every open mind, giving him possibilities to play and work, to construct and represent, search, explore and express, augmenting reality into the complex network of information flow between visible and invisible space.

A method of creating a transparent space based on mixed reality

In this article, we propose a novel idea to create a transparent space. Accidents often happen when a person, a motorcycle, a car, etc., comes out suddenly from a blind corner. In such a place, if the shielding objects become transparent, hidden objects reveal themselves. This may contribute to preventing a lot of accidents. The proposed method creates a transparent space by the employment of a mixed-reality technique and a simple three-dimensional (3-D) recovery technique. The 3-D virtual space is created by a single camera image in real-time, and it is superposed onto a real space employing see-through vision. The observer can watch a dynamic scene of the invisible space through the object in real-time. In the experiment performed, an observer could watch persons walking around in a space hidden by an opaque partition. Future application of this technique may include its installation at various corners in buildings or at intersections on roads with bad visibility. This would surely contribute to reducing traffic accidents in future.

B123 ミリ波レーダによる濃煙空間の計測・可視化手法の検討

In this paper, we aim at visualizing smoke-filled space in front of fire crews using millimetric wave radar sensor. Our proposed system is composed of the millimetric-wave radar, a stereo camera, and gyroscope sensor attached on them. Millimetric-wave has a property of filtering out smoke. The FM-CW millimetric-wave radar can output a 2D reflection density values from obstacles for one-time scanning in invisible space. As for visible space by eyesight, we utilize the 3D stereo camera which can capture a 3D distance map with color information in an angular field of view. Both of the sensors have the capable of real-time scanning (10 frames/sec), and we manually operate them to scan target space. The scanned frame data is stored with 3D direction information from a gyroscope sensor. To construct the 3D space map, we integrate the 2D maps from the millimetric-wave radar and the 3D maps from the stereo camera using the gyroscope data.

Space and Reference in Drama

If, following Beckett's example, one can banish from a play various elements, such as movement, or even dialogue, the element that must remain constant and be retained in any text written for theatrical performance is, of course, space. A play when enacted must take place somewhere. Its performance must occur in some real, visible space, on a stage or in an area fulfilling that purpose. That much is obvious. But what is perhaps less obvious is how complex space in drama is, once it is subjected to analysis. In the case of narrative, when we talk of space, we are normally referring to one of two kinds of space the space of language (the text itself considered spatially) (Genette, 1969:43-48), or the language of space, namely the words cueing the reader and enabling him to participate in the illusion of the verbal creation of geographic space (cf. Issacharoff, 1976:10-19, 1978:1-5). In narrative, however, since there can be only one channel transmitting space verbal language its mode of existence is relatively simple. Space in narrative, then, is mediated by language, and its perception by the reader can only occur through the verbal medium. In the theater, on the other hand, space is a much more complicated phenomenon, embracing several conceivable theatrical areas. A fundamental distinction must be drawn, first of all, between the two entities: space on stage and space off stage, between what is shown to an audience and what is not. That problem alone is the epitome of controversies and aesthetic theory spanning some three hundred years of French theater! Moreover, dramatic tension is often contingent on the antinomy between visible space represented and invisible space described. I shall return to this distinction later. The main point to bear in mind for the moment is that unlike space in narrative, space in drama is not one-dimensional and it is best classified in accordance with its mode of transmission by the encoder and perception by the decoder.

Radiation pattern, reactive power, and resistive aperture antennas

Novel expressions are established for the active and reactive powers of a radiating aperture as integrals, extended to the visible and invisible space of the wave−number plane, of quadratic forms involving the components (in a chosen vector basis) of the Fourier Transform (FT) of the transverse electric field. The physical counterpart of a certain choice of the basis is a particular decomposition of the radiation patterns into two partial patterns differently polarized. As an application of this formalism it is shown that the components of the radiation pattern polarized in the plane of incidence (for each direction of propagation) or orthogonal to it are related to the capacitive and inductive terms in the reactive power. It is also established that a circularly polarized pattern is necessarily associated with zero reactive power. More general conditions are then established and it is shown that zero reactive power is obtained when the Plane Wave Spectrum (PWS) representing the aperture field has certain properties of rotational symmetry on the wave−number plane. An eigenvalue equation (defining those conditions) is established and the structures of the solution discussed. The physical antenna structures whose field can be represented by a PWS of the type studied are then identified with self−complementary apertures having rotational symmetry. Their inherent broad−band properties are briefly discussed from the viewpoint of PWS theory.