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Breast cancer remains the most frequently diagnosed cancer and is the leading cause of neoplastic disease burden for females worldwide, suggesting that effective therapeutic and/or diagnostic strategies are still urgently needed. In this study, a type of indocyanine green (ICG) and camptothecin (CPT) co-loaded perfluorocarbon double-layer nanocomposite named ICPNC was developed for detection and photochemotherapy of breast cancer. The ICPNCs were designed to be surface modifiable for on-demand cell targeting and can serve as contrast agents for fluorescence diffuse optical tomography (FDOT). Upon near infrared (NIR) irradiation, the ICPNCs can generate a significantly increased production of singlet oxygen compared to free ICG, and offer a comparable cytotoxicity with reduced chemo-drug dosage. Based on the results of animal study, we further demonstrated that the ICPNCs ([ICG]/[CPT] = 40-/7.5-μM) in association with 1-min NIR irradiation (808 nm, 6 W/cm2) can provide an exceptional anticancer effect to the MDA-MB-231 tumor-bearing mice whereby the tumor size was significantly reduced by 80% with neither organ damage nor systemic toxicity after a 21-day treatment. Given a number of aforementioned merits, we anticipate that the developed ICPNC is a versatile theranostic nanoagent which is highly promising to be used in the clinic.

When a rotary machine is running, from which the acquired vibro-acoustic signals enable to reveal its operation status and health condition. The study proposed a DSP-based adaptive angular-velocity Vold-Kalman filtering order tracking (AV2KF_OT) algorithm with an online real-time nature for signal interpretation and machine condition monitoring. Theoretical derivation and numerical implementation of computation schemes are briefly introduced. An online real-time monitoring system based on the AV2KF_OT algorithm, which was implemented through both a digital signal processor and a user interface coded by using LabVIEW, was developed. Two experimental tasks were applied to justify the proposed technique, including (i) the detection of startup on the fluid-induced whirl performed through a journal-bearing rotor rig, and (ii) the separation of close orders from the measured signals of a multifunction transmission-element ball-bearing bench.

The use of inertial measurement units associated with various algorithms has been proposed and developed to evaluate functional abilities and kinematics for stroke patients. In previous research, complex mathematical models were adopted successfully to clarify and to validate the functional results from different sensors. However, only a few algorithms stemmed from the process of motor recovery after a stroke or the way to administer clinical assessment scales. Based on the recovery process or how to conduct the assessment scales, the algorithmsensor based module is supposed to accurately classify clinical motor recovery status and to provide additional kinematics in stroke survivors. In this study, only one sensor is affixed on the dorsum of the affected foot to reduce the burden on a weak extremity. A special movement while in seated, extend their knee and then dorsiflex their feet, based on the motor recovery process after stroke is proposed and tested to classify Brunnstrom stages for lower extremities. After analyzing 24 participants and adopting suitable threshold values for different Brunnstrom stages, the overall accuracy is 86.8%. The ability to distinguish Brunnstrom stage II from others can even reach a 100% accuracy. The accuracies for distinguishing Brunnstrom stage III, stage IV, and stage V are 86.6%, 94 %, and 92.8%, respectively. We also analyze these misclassified data and investigate why the errors occurred. The results reveal the feasibility of the kinematics-based algorithm even using a single sensor.

The phenomenon of fluid-induced instability existing in fluid-film bearing systems has been coped with for long time. The study aims to soothe and even eliminate the occurrence of whirl in rotary machinery by increasing the threshold of instability through the anti-swirl injection using the linear quadratic regulator based optimal control. An acceptance region was established in order to decide starting up the control process. Three case studies were carried out to illustrate the effectiveness of the control scheme. The research results demonstrate that the control scheme incorporating with the acceptance region enables to avoid the occurrence of fluid induced instability in rotary machinery. Moreover, the developed techniques can also be applied in other fluid-induced instability problems such as whip and rub, etc.

The influence of fabrication parameters on ZnO film properties has been analyzed through conducting several experiment processes to develop an appropriate deposition condition for obtaining highly c-axis textured films. A transducer with the structure of Al/ZnO/Al/Si was fabricated at low deposition rate and under a temperature of 380 °C in a mixture of gases Ar:O2 = 1:3, and RF power of 178 W. Pt/Ti was employed as the bottom electrode of the transducer fabricated in a suitable substrate temperature, which starts increasing at 380 °C with an increment of 20 °C for each 2 h stage of the deposition. Highly c-axis textured ZnO films have been successfully deposited on Pt/Ti/SiO2/Si substrate under feasible conditions, including RF power of 178 W, substrate temperature of 380 °C, deposition pressure of 1.3 Pa and Ar:O2 gas flow ratio of 50%. These conditions have been proposed and confirmed through investigating the influences of the sputtering parameters, such as substrate temperature, RF power and Ar:O2 gas flow ratio, on the properties of ZnO films.

Self-excited reverse precessional full annular rub, known as “dry whip”, is a secondary phenomenon resulting from a primary cause and may lead to a machine catastrophic failure; i.e., “coexistence of oil and dry whips” which occurs repeatedly with constant frequency and amplitude in small clearance cases. This paper presents a technique using an electromagnetic actuator, which can raise the threshold of instability of fluid-film bearings and then eliminate both oil and dry whips in the normal, operational range. The study constructs a set of experimental setup, sets up a general model of a rotor-bearing-seal system with an electromagnetic actuator to derive the corresponding governing motion equations, evaluates the supplemental stiffness supplied by the electromagnetic actuator, judges instabilities by root locus plots, and finally establishes a set of criterion for eliminating coexistence of oil and dry whips. Experimental results demonstrate that the coexistence of the oil and dry whips of the rotating machine can be removed effectively. The proposed technique can be used to diagnose rub and fluid-induced instability in this kind of rotating machine.

This paper describes an experimental investigation of whirl elimination of a hydrodynamic bearing with an electromagnetic exciter (EE) and includes a stability analysis through a root locus plot. The test apparatus incorporates the EE, which provides additional stiffness through a PD algorithm in order to stiffen a rotating machine to resolve fluid-induced instability. The stiffness of the hydrodynamic bearing gives a significant contribution to the occurrence of unstable vibrations as the speed or the load of a rotating machine increases. With regard to the whirl-eliminated investigations, the EE used to raise the stiffness of the rotating machine can cause important changes in the stability of the rotating machine. The threshold of stability derived in this paper that affects stability conditions can be used to define the stability margin of the rotating machine. A simple control scheme is used to calculate the amount of the supplemental stiffness supplied by the EE, and is confirmed through experiments. To offer a faster, more stable and more effective strategy for whirl elimination, the dynamic behavior of a rotor system affected by fluid-induced whirl instability phenomena has been successfully studied.

The study aims at improving the image quality of 23'' commercial thin-film transistor-liquid crystal display (TFT-LCD) TVs caused by temperature increase on panels. Both the numerical simulation and measurement of temperature distributions characterize the thermal features of TV panels under normal operation. Simulation results justified by experimental data verify the numerical modeling, and characterize thermal phenomena both on the panel and in the backlight unit (BLU) as well. Opening apertures on BLU provide heat dissipation on the direct-lit BLU, and effectively lower the whole temperature distribution of TFT-LCD TVs without adding extra heat dissipation modules. This leads to improve image quality on the panel.

In clinical settings, traditional stroke rehabilitation evaluation methods are subjectively scored by occupational therapists, and the assessment results vary individually. To address this issue, this study aims to develop a stroke rehabilitation assessment system by using inertial measurement units. The inertial signals from the upper extremities were acquired, from which three quantitative indicators were extracted to reflect rehabilitation performance during stroke patients’ movement examination, i.e., shoulder flexion. Both healthy adults and stroke patients were recruited to correlate the proposed quantitative evaluation indices and traditional rehab assessment scales. Especially, as a unique feature of the study the weight for each of three evaluation indicators was estimated by the least squares method. The quantitative results demonstrate the proposed method accurately reflects patients’ recovery from pre-rehabilitation, and confirm the feasibility of applying inertial signals to evaluate rehab performance through feature extraction. The implemented assessment scheme appears to have the potential to overcome some shortcomings of traditional assessment methods and indicates rehab performance correctly.

One of the ECG signal processing aims is to smooth the data to reduce high-frequency artifacts and to retain features within the waves. Conventional techniques may cause reduction on R-wave peaks such that the reduced ratio of R to T wave may cause misdiagnosis. In the study, the Gabor spectral tracking technique is first proposed and implemented to cope with this drawback without missing tiny significant information after noisy interferences are removed. Using the proposed technique to obtain smoothed ECG signals can be an effective tool for clinic or diagnostic purpose.

Three computation schemes of time-frequency representations have been developed and implemented to identify different components of mechanical noise emitted from the transmission system of electrical vehicles. This study explores the close relationships between three time-frequency representations, i. e. the spectrogram based on windowed Fourier transform, the Wigner-Ville distribution, and the smoothed Wigner-Ville distribution. One main purpose is to pursue the efficiency of computing the smoothed Wigner-Ville distribution of a dynamic signature. The revised scheme can tremendously reduce the computation time to a scale of around 1/90, compared with the original scheme. To assess the validation of these time-frequency representation schemes, firstly, four synthetic signals are designed and processed. Secondly, the developed time-frequency representations are applied to distinguish different spectral components of transmission noise, and identify their sources. This study takes an electrical scooter with a continuous variable transmission system as a test bench. The continuous-variable-transmission-belt noise, helical-gear whine noise, and fan noise can be clearly identified via the processing of the time-frequency representations. These obtained conclusions can be used as references for machine element modification to reduce annoying noise.

X-ray mammography has been used in the early detection of breast tumors for decades. Related techniques to enhance preventive screenings are still demanding. Since the 1990s, near infrared diffuse optical tomography (NIR DOT), a functional medical imaging modality, is being exploited and developed to reconstruct optical-coefficient images of tissues. Much endeavor to improve the spatial resolution and contrast of DOT images has been exerted for clinic applications in the diagnosis of breast tumors. The study aims at the design, implementation, and verification of a mammography based NIR DOT. This multimodality imaging method is able to provide information that neither X-ray nor diffuse optical tomography can give alone. To this end, a device with multiple-channel switching of NIR sources and translational scanning of out-emitted intensity constructed on a commercialized mammography system is being designed and built up. We employ the mammography image as structure information that is used as an initial guess for the image reconstruction of optical properties of tissues. Preliminary numerical trials are performed using heterogeneous phantoms made of high-scattering Intralipid. Promising results are obtained with various spatial resolutions due to partial NIR detected intensity.

Dental implants are generally used in edentulous patients. The key issue of this dental surgery is the effective osseointegration of implants with spongy bone and cortical bone and then they become a part of loading structure. Current osseointegration detection devices only offer overall evaluation without the information of location and orientation of bone defects. This study is to develop detection techniques to measure the quantity as well as to locate the orientation of imperfection around bone-implant interface based on resonance frequency analysis (RFA). A noncontact measurement technique is performed with acoustic excitation through a loud-speaker and displacement response via a capacity-type pick-up. In the first and second series experiments, RFA is applied to estimate the orientation and quantity of irregular bone defects on various in-vitro faulty models. The variation in RF not only locates the orientation and depth of defects but also reflects the change of boundary conditions surrounding the defective models. According to these results, the detection technique to locate irregular osseointegration is established. Furthermore, the detection device to this end is proposed as well. The proposed examining approach and device are promising and able to assist dentists in dental implant surgery.

A promising method to achieve rapid convergence for image reconstruction is introduced for the continuous-wave near-infrared (NIR) diffuse optical tomography (DOT). Tomographic techniques are usually implemented off line and are time consuming to realize image reconstruction, especially for NIR DOT. Therefore, it is essential to both speed up reconstruction and achieve stable and convergent solutions. We propose an approach using a constraint based on a Lorentzian distributed function incorporated into Tikhonov regularization, thereby rapidly converging a stable solution. It is found in the study that using the proposed method with around five or six iterations leads to a stable solution. The result is compared to the primary method usually converging in approximately 25 iterations. Our algorithm rapidly converges to stable solution in the case of noisy (>20 dB) detected intensities.

We attempt to develop a systematic scheme through adopting high-pass filtering (HPF) to well resolve value-preserved images such as medical images. Our approach is derived from the Poisson maximum a posteriori superresolution algorithm employing the HP filters, where four filters are considered such as two low-pass-filter-combination based filters, wavelet filter, and negative-oriented Laplacian HP filter. The proposed approach is incorporated into the procedure of finite-element-method (FEM)-based image reconstruction for diffuse optical tomography in the direct current domain, posterior to each iteration without altering the original FEM modeling. This approach is justified with various HPF for different cases that breast-like phantoms embedded with two or three inclusions that imitate tumors are employed to examine the resolution performances under certain extreme conditions. The proposed approach to enhancing image resolution is evaluated for all tested cases. A qualitative investigation of reconstruction performance for each case is presented. Following this, we define a set of measures on the quantitative evaluation for a range of resolutions including separation, size, contrast, and location, thereby providing a comparable evaluation to the visual quality. The most satisfactory result is obtained by using the wavelet HP filter, and it successfully justifies our proposed scheme.

In this paper, a flexible edge-preserving regularization algorithm based on the finite element method is proposed to reconstruct the optical-property images of near-infrared diffuse optical tomography. This regularization algorithm can easily incorporate with varied weighting functions, such as a generalized Lorentzian function, an exponential function, or a generalized total variation function. To evaluate the performance, results obtained from Tikhonov or edge-preserving regularization are compared with each other. As found, the edge-preserving regularization with the generalized Lorentzian function is more attractive than that with other functions for the estimation of absorption-coefficient images concerning functional tomographic images to discover functional information of tested phantoms/tissues.

In this study, we first propose the use of edge-preserving regularization in optimizing an ill-conditioned problem in the reconstruction procedure for diffuse optical tomography to prevent unwanted edge smoothing, which usually degrades the attributes of images for distinguishing tumors from background tissues when using Tikhonov regularization. In the edge-preserving regularization method presented here, a potential function with edge-preserving properties is introduced as a regularized term in an objective function. With the minimization of this proposed objective function, an iterative method to solve this optimization problem is presented in which half-quadratic regularization is introduced to simplify the minimization task. Both numerical and experimental data are employed to justify the proposed technique. The reconstruction results indicate that edge-preserving regularization provides a superior performance over Tikhonov regularization.