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101.
We consider a simple one-dimensional system whose observations are sent to a state estimator over a noisy binary communication link. The interesting thing about the system is that it is unstable. The problem is to design an encoding scheme and a decoder such that the estimation error is stable. We explicitly construct a simple but efficient estimator for the binary symmetric channel (BSC). We are not aware of any such previous "codes" for the BSC. We compare our results to the nonconstructive bounds of Sahai.  相似文献   
102.
In the formulation of equations of motion of three-dimensional mechanical systems, the techniques utilized and developed to analyze the electrical networks based on linear graph theory can conveniently be used. The success of this approach, however, relies on the availability of a complete and adequate mathematical model of the rigid body valid in the three-dimensional motion. This article is devoted to the derivation of such a mathematical model for the rigid body as a (k + 1)-port component. In this derivation, the dynamic properties of the rigid body are automatically included as a consequence of the analytical procedures used in the article. In this model, a general form of the terminal equations is given. In many applications, however, its special form, also given in this article, is used.  相似文献   
103.
104.
The goal of this study is to investigate the reconstruction of three-dimensional (3-D) graphical models of real objects in a controlled imaging environment and present the work done in our group based on silhouette-based reconstruction. Although many parts of the whole system have been well-known in the literature and in practice, the main contribution of the paper is that it describes a complete, end-to-end system explained in detail. Based on a multi-image calibration method, an algorithm to extract the rotation axis of a turn-table has been developed. Furthermore, this can be extended to estimate robustly the initial bounding volume of the object to be modeled. The disadvantages of the silhouette-based reconstruction can be removed by an algorithm using photoconsistency. This algorithm has a simpler visibility check, and it eliminates the selection of threshold existing in similar algorithms. Besides, in order to construct the appearance, we use the concept of particles. The reconstruction results are shown both on real world and synthetic objects.  相似文献   
105.
Periodontal diseases are considered as old as the history of mankind, Magical, religious and herbal treatments were demonstrated in almost all of the early writings. However, methodical, carefully reasoned therapeutic approaches did not exist until the middle-ages and modern treatment with a scientific base and sophisticated instrumentation did not develop until the 18th century. Prior to the 1950s, diseases were mostly treated by root debridement and the extraction of the affected teeth. Until the 1970s, it was primarily the symptoms of periodontal diseases that were treated. The goal was radical elimination of the periodontal pocket (resective therapy). The means were gingivectomy, flap procedures and osseous surgery. The disadvantages were the massive sacrifice of periodontal tissues, lack of regeneration and clinically elongated teeth. These disadvantages, along with the realization of the importance of aetiologic agents, raised questions about the necessity of total pocket elimination, and the control of subgingival infection by a thorough scaling and root planing (nonsurgical therapy), with and without antibiotics, became a commonly used treatment during the 1980s. Comparative longitudinal studies, surgical versus nonsurgical, demonstrated that both surgical and nonsurgical therapy result in limited regeneration and healing with a long junctional epithelium. The most important aspects of today's modern concept of periodontal therapy are causal, regenerative, and specific for disease type and severity. Although the regeneration of the periodontium can be accomplished with the biological principles of guided tissue regeneration and graft materials, compared to conventional methods, the restoration of a completely normal periodontal status has not yet been achieved. We are about to reach our ultimate goals and presently, the more promising research directions for a substantial regeneration seems to lie in biological mediators. Although the future of periodontal therapy is bright, it is still of critical importance to have a preventive strategy to keep individuals healthy beforehand.  相似文献   
106.
The intrinsic viscosity data of linear poly(4-chlorostyrene) in n-propylbenzene and isopropylbenzene were used to estimate the equation of state exchange energy (X12) and entropy (Q12) parameters. The quantities estimated for X12 were 6.7 and 8.1 J cm?3 and those of Q12 were ?0.069 and ?0.063 J cm?3 deg?1 in n-propylbenzene and isopropylbenzene, respectively. The average values of the chain unperturbed dimension constant (Ko) and the characteristic ratio (Cx) were found to be 0.55 × 10?3 dl mol1/2g?3/2 and 10.54, respectively, from the intrinsic viscosities measured at the corresponding θ-temperatures.  相似文献   
107.
We have investigated the toxicity of dose-escalation of BCNU, etoposide and melphalan ('BEM') chemotherapy with autologous stem cell transplantation in patients with haematological malignancies. Seventy-two patients with haematological malignancies were treated with BCNU (600 mg/m2, 450 mg/m2 or 300 mg/m2), etoposide 2 g/m2 and melphalan 140 mg/m2 followed by autologous bone marrow transplantation (ABMT), n = 51, or autologous peripheral blood progenitor cell transplantation (APBPCT), n = 21. Liver and pulmonary function was monitored pretransplant and at regular intervals post-transplant. Mucositis was graded daily during in-patient stay. There was a significantly higher incidence of symptomatic pulmonary toxicity in the patients who received BCNU at 600 mg/m2 than in the other two groups, and there was a significant increase in the incidence of asymptomatic decrease in carbon monoxide (KCO) in the patients who received BCNU 450 mg/m2. There was no significant difference between the three groups in the incidence and severity of mucositis or in the incidence of transiently abnormal liver function. We conclude that etoposide at 2 g/m2 can be used without unacceptable mucositis. BCNU at 600 mg/m2 is associated with an unacceptably high incidence of lung toxicity, but at 450 mg/m2 there is minimal symptomatic lung toxicity.  相似文献   
108.
A sound in-plant pollution control strategy can only be defined by paying due attention to bio-recalcitrance and toxicity. In this context the levels of toxicity and inert COD introduced to textile dyebath discharges by two alternative auxiliary chemicals, namely natural tannin (NT) and synthetic tannin (ST), were investigated. The effect of 40 minutes ozonation at 1,000 mg h(-1) at pH 3.5 on the segregated effluent streams containing the above-mentioned tannin formulations was evaluated in terms of changes in toxicity and recalcitrance. The effect of ozonation on the COD distribution of raw and ozonated NT and ST samples according to their molecular weight cut-offs was also assessed. Both untreated tannin formulations exerted high acute toxicity towards marine microalgae Phaeodactylum tricornutum. Moderate decrease in the toxicity levels of both tannins was observed upon ozonation. The raw NT formulation with a COD content more than twice that of its alternative raw ST had an initially inert soluble COD content of only 25 mg/L, while the initially inert COD was 135 mg/L for ST. As the initially inert soluble COD content of NT was considerably lower, this textile auxiliary did not need chemical pretreatment to improve its biodegradability. On the other hand, the initially inert soluble COD content of ST was reduced by 70% by ozone pretreatment. In terms of residual COD contents achievable after passing through a biological treatment system, raw NT and pretreated ST formulations yielded 100 and 95 mg/L COD, respectively. The highest proportion of COD (46% for NT and 88% for ST) was found in the <1 kDa range. The same fraction increased to 93% for NT after ozonation, while for ST no significant change was observed in the COD distribution of the molecular weight cut-offs after ozonation.  相似文献   
109.
Intrinsic viscosities of poly(4-chlorostyrene) solutions in isopropyl-benzene and n-propylbenzene at temperatures above and below the theta (θ) temperatures of these solvents were measured using a capillary viscometer. The viscosity measurements were performed on three poly(4-chlorostyrene) samples having molecular weights (M?;v) 1.75 × 106, 6.5 × 105 and 2.7 × 105. A smooth and continuous contraction below the θ temperatures was observed for both solvents. The temperature dependence of [/eta] can be represented by a master curve in a plot of α3/eta|/tau|M1/2 (g1/2 mol?1/2) versus |/tau|M1/2 (g1/2 mol?1/2), where α/eta = [/eta(T)]/[/eta(θ)]1/3 is the expansion factor and /tau = (T - θ)/T is the reduced temperature. A universal plot of reduced viscosity size (α/eta) versus reduced blob parameter (N/Nc) shows the achievement of collapsed state for T<θ. The prediction of thermal blob theory is also verified for T > θ. The temperature dependence of intrinsic viscosity, both below and above the θ temperature, exhibits similar behaviour to the temperature dependence of dipole moments for both of these solvents.  相似文献   
110.
Byler's syndrome is a rare form of autosomal recessive intrahepatic cholestasis that is fatal in children. A 10-year-old girl diagnosed with Byler's syndrome underwent reduced-size liver transplantation using lateral segments of her living mother's liver. The donor's and the recipient's liver functions after transplantation were evaluated using Tc-99m disofenin and Tc-99m SC to investigate morphology, liver perfusion, and hepatobiliary function.  相似文献   
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