Digital Apparatus Research Articles

Low Cost Setup to Support PID Ideas in Control Engineering Education

A laboratory equipment that has been employed in experimental activities to code real-time PID control algorithms is described in this paper. This digital apparatus, including a MTG plant (motor+tachometer) and a simple data acquisition board, is flexible to assess not only PID controller loop methodologies but also tuning and design aspects. Among the different possibilities of using a PID control algorithm, the students can realize and be in touch with their own control code implementation. These essays raise, a bit more, the motivation for PID control lessons. In particular, the whole real-time equipment operates in the industrial pattern of voltage, is cheap and is easy to install as standard control equipment in any control laboratory. The main advantage is the very low cost if compared to similar laboratory scale educational setup. Three control tasks for the students in a discipline called Feedback Systems are taken as examples and evaluation results from the students are shown.

DIRECT DIGITAL SPEAKER APPARATUS HAVING A DESIRED DIRECTIVITY PATTERN

Direct digital speaker apparatus receiving a digital input signal and generating sound accordingly, the apparatus comprising an array of pressure-producing elements and a controller operative to compute a timing pattern determining if and when each pressure-producing element is actuated so as to achieve a desired directivity pattern.

Zanik powłok brzusznych po zabiegach operacyjnych

The aim of the studywas to analyze clinical material concerning postoperative atrophy of abdominal integument.Material and methodsThe evaluated group consisted of 29 patients with sonographically revealed atrophy of the abdominal wall. Those changes were observed after various surgical procedures: mainly after long, anterolateral laparotomies or several classical operations. Ultrasound examinations up to the year 2000 were performed with analog apparatus, in the latter years only with digital apparatus with linear transducers (7–12 MHz) and sometimes convex type conducers (3–5 MHz). The location, size and intestine stratified wall structure were evaluated. In each case the integument thickness was measured in millimeters in the site of the greatest atrophy and it was compared with the integument thickness from the side that had not been operated which enabled the calculation of the percentage reduction of integument in the area of the scar.ResultsIn 3 patients who underwent several laparotomies there was a total reduction of muscular mass in the operated area. In these cases we stated only skin and slightly echogenic subcutaneous strand; probably corresponding to fibrous tissue – the thickness of integument in this area was in the range from 3 to 8 mm. In the remaining 26 patients the integument atrophy on the scar level included muscles in a greater extent and covered an extensive area after classical urological procedures on the upper urinary tract: after nephrectomy and even ureter stone evacuation or kidney cyst excision by means of classical anterolateral approach with the integument incision on the length of almost 20 cm. Reduction in the integument thickness was observed on the smaller area after classical cholecystectomies, appendectomies and other surgical procedures with the incision across the integument. The integument atrophy in the operated sites expressed in absolute numbers was in the range of 7–20 mm (average 14 mm). These values are markedly lower than the comparative integument thickness on the not operated side: 17–52 mm (average 25.4 mm). The percentage value of the integument thickness reduction oscillated in the range of 32–67% (average 44.2%). In most cases the atrophy involved all layers of the abdominal wall, what demonstrated as regional prominence of the integument, mimicking the presence of hernia.ConclusionsUltrasonography allows precise evaluation of the size and extent of atrophy as well as depiction of other lesions simulating that effect. Establishing the correct diagnosis should prevent the unnecessary reconstructions of the abdominal integument.

Digital Receive-Focusing Apparatus Using Analogue Multiplexers

A digital receive-focusing apparatus for receive-focusing ultrasound channel signals from a plurality of transducers in an ultrasound imaging system is provided. The digital receive-focusing apparatus in accordance with the present invention comprises a plurality of channel modules responsive to the ultrasound channel signals for producing a receive-focused beam. Each of the plurality of channel modules comprises an analogue multiplexer for multiplexing at least two ultrasound channel signals and a signal processor for digitally processing and compensating the multiplexed signal.

Characterization of Indoor-Air Bioaerosols in Southern Taiwan

This study investigated indoor air quality (IAQ) at 39 public sites in southern Taiwan including hospitals, schools, office buildings, hypermarkets, libraries, railway stations, theaters, etc. Indoor air quality was preliminarily assessed using handy digital apparatus. Items detected include carbon dioxide (CO2), carbon monoxide (CO), formaldehyde (HCHO), total volatile organic compounds (TVOCs), total bacteria counts (TBC), total fungi counts (TFC), PM10, PM2.5, ozone (O3) and temperature. Based on the results of walk-through detection, the spatial distribution of indoor air contaminants was further measured over a 24 hour period using the EPA standard method. Major indoor air pollutants were found to include CO2, TBC, and TFC. The measured CO2 concentrations ranged between 438 and 1527 ppm, and only 38.9% of them met the Taiwan EPA suggested threshold of 600 ppm. In the schools and hospitals (Category 1), the measured TFC and TBC concentrations ranged from 62 to TNTC CFU/m3 and from 196 to 4875 CFU/m3, respectively. 33% TFC and 83% TBC concentrations exceeded the suggested threshold, and CO2 concentrations were moderately correlated with TBC levels. In a case study of hospital bioaerosols, high TBC and TFC levels were effectively lowered through disinfectant housekeeping as well as ClO2 spray. Three filamentous fungus genera were identified as Cladosporium perangustum, Cladosporium tenuissimum, and Fusarium incarnatum from outdoor samples with high TFC concentrations.

Tripping through runtime

“Tripping through” is an invitation to plunge into the invisible relationships of hard and soft computer matter through sensuous mediation. The projects outlined are designed to provoke and capture the specific behavior of individual computer components through the use of appropriate software fragments. If one approaches a digital apparatus with a transducer that transforms electromagnetic fields into acoustic waves, the analytical sphere is changed into concrete acoustical phenomena and enters the world of sensation (electromagnetic emissions can be picked using induction microphones and output as acoustic signals. A suitable example is a Monacor telephone adapter AC-71/3,5MM). In choreographies for software and computer parts, these become actors in noise pieces for and in computers. Machine noises can be mediated for the public. They reveal the activity of computer programs in the widest sense and the activity of the computers or computer parts they are running on. The time and space of computer processes and memory span different levels of reality during “runtime.” Software being processed within this system of coordinates creates its own temporal and spatial dimensions, which are staged for an audience to provide a sensual experience: that of logic encountering the physical world.

Applicability, interests and limitations of the ultrasound examination in the equine deep digital flexor apparatus of the thoracic limb.

The deep digital flexor tendon apparatus is represented by the distal part of the deep digital flexor tendon, the distal digital annular ligament and podotrochlear bursa, being the part of the podotrochlear apparatus most prone to injuries. The purpose of this study was to develop a systematic ultrasonographic approach of this apparatus and to present the accuracy of the ultrasound exam in imaging this anatomical formation. The ultrasound exam was performed on 10 sound horses using the palmar and transcuneal approach. Detailed description of the transverse and longitudinal ultrasonographic images of this region is provided. The ultrasound of the foot has been done with a non-portable machine Aloka Prosound Alpha 10 (Aloka Co. Ltd., 6-22-1 Mure, Mitaka-shi, Tokyo, 181, Japan). Convex and microconvex multifrequence transducers, with a frequency varying between 5.0 to 10.0 MHz have been used. This technique allowed us to image all the components of the deep digital flexor apparatus with the specification that it presents some limitations in examining the collateral parts of the distal deep digital flexor tendon and distal digital annular ligament. The main advantages of this technique are: low cost, short examination time and applicability in the field.

Reproducibility of heart rate variability parameters measured in healthy subjects at rest and after a postural change maneuver

Heart rate variability (HRV) provides important information about cardiac autonomic modulation. Since it is a noninvasive and inexpensive method, HRV has been used to evaluate several parameters of cardiovascular health. However, the internal reproducibility of this method has been challenged in some studies. Our aim was to determine the intra-individual reproducibility of HRV parameters in short-term recordings obtained in supine and orthostatic positions. Electrocardiographic (ECG) recordings were obtained from 30 healthy subjects (20-49 years, 14 men) using a digital apparatus (sampling ratio = 250 Hz). ECG was recorded for 10 min in the supine position and for 10 min in the orthostatic position. The procedure was repeated 2-3 h later. Time and frequency domain analyses were performed. Frequency domain included low (LF, 0.04-0.15 Hz) and high frequency (HF, 0.15-0.4 Hz) bands. Power spectral analysis was performed by the autoregressive method and model order was set at 16. Intra-subject agreement was assessed by linear regression analysis, test of difference in variances and limits of agreement. Most HRV measures (pNN50, RMSSD, LF, HF, and LF/HF ratio) were reproducible independent of body position. Better correlation indexes (r > 0.6) were obtained in the orthostatic position. Bland-Altman plots revealed that most values were inside the agreement limits, indicating concordance between measures. Only SDNN and NNv in the supine position were not reproducible. Our results showed reproducibility of HRV parameters when recorded in the same individual with a short time between two exams. The increased sympathetic activity occurring in the orthostatic position probably facilitates reproducibility of the HRV indexes.

Three dimensional imaging of melanocytic lesions with a novel digital apparatus and with the use of laser

Three dimensional imaging of melanocytic lesions with a novel digital apparatus and with the use of laser

Improvement of Technical Parameters of an X-Ray Scanning Apparatus

Results of improvement of utility coefficient of X-ray digital scanning apparatuses and reduction of patient radiation dose are discussed. The multiline detector PR4000 was developed to attain this goal. This detector implements the time delay principle and signal averaging method. The pixel size is controlled in the detector. This provides an increase in the diagnostic capacity of the X-ray scanner. X-Ray digital scanning apparatus ARSTs-02-N with detector PR4000 provides diagnosis of both bone structure (spatial resolution, ≥4 pairs of lines/mm) and X-ray diagrams with resolution ≥2 pairs of lines/mm. Radiation dose in lateral projection of the patient’s lumbar segments is reduced.

Use of stereoscopic vision for analysis of digital X-ray images of lungs

The fundamental principles of digital stereoroentgenography are considered. A special adapter to digital X-ray diagnostic apparatus used to obtain X-ray stereoscopic pairs and Stumpf stereoscopic binoculars for analysis of stereoscopic photographs are described. Specific features of the stereoscopic model of lungs and an exemplary clinical case are considered.

Application of loading and digital measurement apparatus in four-part fracture model of proximal humerus

目的 通过制备肱骨近端四部分骨折模型及成熟的加载测量装置,以进行有关肱骨近端人工关节置换的相关生物力学研究.方法 采集新鲜成人肩关节尸体标本8对16具,应用截骨的方法制成肱骨近端四部分骨折模型,对其进行人工假体重建,并分为解剖重建组和重叠重建组.设计并制作模型加载装置及光学测量装置.测定在肩关节处于不同运动角度时,大结节相对于肱骨干骺端的位移情况.检验整套装置是否具有稳定的可重复性.结果 成功制成肱骨近端四部分骨折模型.各个标本在肩关节运动至各个不同角度时,多次重复相同的肩关节运动,其大结节的位移值基本一致或相差很小.检测中发现大结节在肩关节活动过程中有明显移位,在个别标本中甚至超过20 mm.结论 本试验所设计的加载及测量方式可成功模拟肱骨头置换术后肩关节在进行被动活动的过程中,大结节所受的生物力学作用及在此作用下大结节的位移情况.现有的针对人工肱骨头置换的大结节固定方法,在术后即刻的关节被动活动中,仍可导致大结节相对骨干的明显位移。

Digital hearing aid battery conservation method and apparatus

A digital hearing aid adjusts power to a processor or other modules to conserve battery life. The digital hearing aid receives and measures audio signals from an environment. If a magnitude of the audio signals is less than a predetermined threshold, the digital hearing aid starts a timer. If the audio signals are below the threshold for a predetermined period as measured by the timer, the digital hearing aid adjusts power to the processor or other modules. The digital hearing aid may also adjust clock rates and sampling rates of the processor. If the digital hearing aid detects audio signals above the threshold, the digital hearing aid restores power to the processor or other modules.

Investigation into Influences of Visual Apparatus Sensor and Executor Characteristics on the Quality of Information Transmission to Sensory Organs

Analysis into the effects of parametric characteristics of visual aid on the perception level of information transmitted has led to the possibility of examining and determining the quality of the reading level as a function of certain parameters of a digital apparatus (sensor), the distance to the text, the size of letters and the intensity of light. Efforts have been made to evaluate the effect of the specifications of the executor as well as the information transfer (by tactile way) speed onto the sensory organs of the disabled person at the perception level. A choice has been made of rational information transfer speeds and appropriate visual aid characteristics to facilitate an adequate perception level.

The Application of Ultrasound Contrast Agents in the Characterization of Renal Tumors

The aim of this article is to describe the current ultrasound (US) contrast agents employed in the characterization of renal tumors and to report our experience in the use of a contrast-specific ultrasound technique pulse inversion harmonic imaging (PIHI).A total of 23 renal masses were prospectively evaluated by conventional US, CDUS, PIHI and finally by helical-CT (HCT). The study was performed using a wideband convex array 2-5 MHz transducer and a US digital apparatus . PIHI scanning of each renal mass was performed before and after the injection of Levovist. To reach a definitive diagnosis HCT and/or histological findings were considered as the reference procedures. Eleven solid renal cell carcinomas (RCCs), one embryonal metanephric adenoma (EMA), seven angiomyolipomas (AMLs), and four cystic RCCs were analyzed. Solid RCCs revealed a higher contrast enhancement than AMLs with a typical pattern on conventional US. The EMA and AML with an atypical pattern revealed intense contrast enhancement during the arterial phase, progressively decreasing during the delayed phase. Cystic RCCs showed intense contrast enhancement on the peripheral thick wall during the arterial phase decreasing during the delayed phase. PIHI with Levovist may differentiate solid RCCs from AMLs with no hypervascular pattern while solid RCCs show a higher intensity of contrast enhancement than hypervascular AML.

Mapping the Narrative in a Digital Album Cover

Mapping the Narrative in a Digital Album Cover

Comparative kinetic analysis reveals that inducer-specific ion release precedes the mitochondrial permeability transition

Relationships among the multiple events that precede the mitochondrial membrane permeability transition (MPT) are not yet clearly understood. A combination of newly developed instrumental and computational approaches to this problem is described. The instrumental innovation is a high-resolution digital apparatus for the simultaneous, real-time measurement of four mitochondrial parameters as indicators of the respiration rate, membrane potential, calcium ion transport, and mitochondrial swelling. A computational approach is introduced that tracks the fraction of mitochondria that has undergone pore opening. This approach allows multiple comparisons on a single time scale. The validity of the computational approach for studying complex mitochondrial phenomena was evaluated with mitochondria undergoing an MPT induced by Ca 2+, phenylarsine oxide or alamethicin. Selective ion leaks were observed that precede the permeability transition and that are inducer specific. These results illustrate the occurrence of inducer-specific sequential changes associated with the induction of the permeability transition. Analysis of the temporal relationship among the multiple mitochondrial parameters of isolated mitochondria should provide insights into the mechanisms underlying these responses.

Complete description and evaluation of hysteresis loop of ferroelectrics

A digital apparatus for automated hysteresis loop measurement and data processing was designed, realized and verified. The key SW operation, the discrete Fourier transform, DFT, allows effective data processing. The results can be presented by many different means: in time, frequency, field and power domain, for instance. The frequency spectrum is used for filtering, elimination of DC component, effective loop approximation etc. In the field domain the spectrum components can be displayed as Lissajouse figures and the instantaneous power of individual harmonics can be visualized. Effective loop approximation allows efficient storing of results from large amount of measurements. Complete data processing and their efficient storing gives a lot of information for the explanation of physical processes, design of ferroelectrics devices, etc.

Portable electronic nose system based on the carbon black–polymer composite sensor array

A portable electronic nose system based on personal digital apparatus has been developed by using the vapor detection array made of carbon black–polymer composites and the user software, such as data acquisition and pattern recognition. The gas sensor array is possible to have maximum 16 sensing elements integrated on the same silicon substrate. The individual element has a Si bulk-micromachined well which allows the polymer-carbon black composite solution to be placed reproducibly in a specific and well-constrained area during the drop-coating process. Preliminary results show that our portable electronic nose system has successfully classified simple volatile organic compounds, and the complex liquor samples of brandy and whiskey.

A digital sedimentator for measuring erythrocyte sedimentation rate using a linear image sensor

A digital apparatus was fabricated to determine accurately the erythrocyte sedimentation rate (ESR) using a linear image sensor. Currently, ESR is utilized for clinical diagnosis, and in the laboratory as one of the many rheological properties of blood through the settling of red blood cells (RBCs). In this work, we aimed to measure ESR automatically using a small amount of a sample and without moving parts. The linear image sensor was placed behind a microhematocrit tube containing 36 μl of RBC suspension on a holder plate; the holder plate was fixed on an optical bench together with a tungsten lamp and an opal glass placed in front. RBC suspensions were prepared in autologous plasma with hematocrit H from 25% to 44%. The intensity profiles of transmitted light in 36 μl of RBC suspension were detected using the linear image sensor and sent to a personal computer every minute. ESR was observed at the settling interface between the plasma and RBC suspension in the profile in 1024 pixels (25 μm/pixel) along a microhematocrit tube of 25.6 mm total length for 1 h at a temperature of 37.0±0.1 °C. First, we determined the initial pixel position of the sample at the boundary with air. The boundary and the interface were defined by inflection points in the profile with 25 μm resolution. We obtained sedimentation curves that were determined by the RBC settling distance l(t) at the time t from the difference between pixel locations at the boundary and the interface. The sedimentation curves were well fitted to an empirical equation [Puccini et al., Biorheol. 14, 43 (1977)] from which we calculated the maximum sedimentation velocity smax at the time tmax. We reached tmax within 30 min at any H, and smax linearly related to the settling distance l(60) at 60 min after the start of sedimentation from 30% to 44% H with the correlation coefficient r=0.993. Thus, we may estimate conventional ESR at 1 h from smax more quickly and accurately with less effort.