Commercial Measurement Devices Research Articles

Ortam Gürültü Şiddetinin, Ios ve Android Tabanlı Ses Ölçüm Uygulamaları ile Ticari Ses Ölçüm Cihazları Kullanılarak Karşılaştırılması ve Ölçüm Belirsizliğinin Elde Edilmesi

In this study, sound measurement between ios and android operating system based mobile phones (Soundmeter, Decibel X) and commercial sound measurement devices (Cem dt8852, Svantek sv104) was tested. Sound measurement intensities and energies were determined, measurement uncertainties of ios and android devices according to the application were determined. Measurements were carried out at the same time in the indoor and outdoor environment. Iphone 7+ (Ios operation system) and Samsung note 8 (Andorid operation system) used. Significant sound measurement differences were obtained between the two different mobile phone applications. There was no significant difference between commercial measurement devices. Commercial measuring devices were calibrated and can be used as reference devices. Using these devices, it was observed that ios and android-based applications receive faulty measurements on average between 10-20%. As a result of the measurements taken with the applications, it was determined that the measurement uncertainty is in the range of approximately 4-5dB.

混相流計測に適用可能な超音波流速分布計測システムの開発

Ultrasonic Velocity Profiler; UVP method is applied to various fluid flows including the multiphase flow. Most UVP measurements were carried out using the commercial measurement devices. However, a flexibility of measurements is restricted due to that fact. This article discusses development of UVP measurement system. The system consists of a pulser/receiver, an ultrasonic transducer, an analog-to-digital converter and a PC. Selection guide of hardware is provided. Velocity estimation is performed with full-digital signal processing, which eliminates complicated adjustment of analog circuits as it used to be. Typical signal processing principle and its efficient implementation are discussed. Bubbly flow measurement using this system is presented as an example of application.

EP-1371: Multipurpose dosimetry phantom for QA in PBS therapy systems with commercial measurement devices

EP-1371: Multipurpose dosimetry phantom for QA in PBS therapy systems with commercial measurement devices

How Can We Predict the Successful Outcome After Treatment in Achalasia Patients? (Gastroenterology 2012;143:328-335)

Typical symptoms of achalasia are dysphagia, regurgitation of undigested food, chest pain, weight loss and respiratory complications. In previous studies, esophageal manometry has been proposed as a useful test to determine whether patients should receive re-treatment. Decreased lower esophageal sphincter (LES) pressure to less than 10 mmHg has been reported to be a good predictor of long-term treatment success.1,2 However, some achalasia patients with persistent symptoms after treatment had low or absent LES pressure.3,4 On the other hand, esophagogastric junction (EGJ) compliance is an important pathophysiological factor in the cases of achalasia and gastroesophageal reflux disease (GERD). A commercial measurement device, EndoFLIP system (endoscopic functional luminal imaging probe; Crospon, Galway, Ireland) was recently introduced to test compliance or distensibility of EGJ. The EndoFLIP uses impedance planimetry to determine multiple adjacent cross sectional areas (CSAs) within a cylindrical bag placed in a tubular organ during volumetric distention. The additional measure of the corresponding intrabag pressure allows assessment of the CSA pressure response (distensibility) of the distended area. Rohof et al5 performed the study to compare the EGJ distensibility and LES pressure as a better and more integrated parameter after treatment in the patients with achalasia. This study was performed in 15 healthy volunteers and 34 patients with achalasia. Healty volunteers underwent EndoFLIP measurement. Achalasia patients underwent esophageal manometry, EndoFLIP measurement of the EGJ, and timed barium esophagography. The symptoms were assessed using the Eckardt score. In 4 patients, the EndoFLIP probe could not pass the EGJ. Remained 30 achalasia patients could take the EndoFLIP test to estimate distensibility. Seven of the 30 patients were newly diagnosed and were measured before and 3 months after treatment. The authors included pneumodilation and laparoscopic Heller myotomy as the treatment options. The authors defined successful treatment as an Eckardt symptom score of ≤ 3. The 30 achalasia patients were divided into the successfully treated group (18 patients) and the treatment failure group (12 patients) by the Eckardt symptom score. Healthy volunteers had a mean EGJ distensibility of 6.3 ± 0.7 mm2/mmHg using a 50 mL volume distention. Untreated patients (0.7 ± 0.9 mm2/mmHg; P < 0.001) had a significantly lower EGJ distensibility compared with healthy volunteers. The EGJ distensibility of both unsuccessfully treated and successfully treated patients was lower than that of healthy volunteers in a 50 mL volume distention (1.6 ± 0.3 mm2/mmHg; P < 0.01 and 4.4 ± 0.5 mm2/mmHg; P = 0.02, respectively). In patients with achalasia, EGJ distensibility correlated with esophageal emptying (r = -0.72; P < 0.01) and symptoms (r = 0.61; P < 0.01) and was significantly increased with treatment. The patients with impaired distensibility and low LES pressure showed significantly more stasis on their timed barium esophagogram compared to the patients with normal distensibility and low LES pressure. The authors concluded EGJ distensibility is a better parameter than LES pressure for evaluating efficacy of treatment for achalasia.

Aerosol Measurement in Low-Pressure Systems with Standard Scanning Mobility Particle Sizers

The scanning mobility particle sizer (SMPS) is one of the best known instruments for measuring particle size distributions in the submicron range. The SMPS consists of two parts: an electrostatic aerosol classifier (differential mobility particle analyser, DMA), followed by a counting device, in general a condensation particle counter (CPC). Unfortunately, commercial measurement devices such as the TSI DMA Model 3071 and the TSI CPC Model 3022 (TSI Inc., St. Paul, MN, USA), can be used only at nearly atmospheric pressure in the sampling line or in slight overpressure mode, but not in low-pressure systems. A modification in the sampling line is shown which enhances the operating range of a standard SMPS system to low pressure. Samples taken under standard and low-pressure conditions show good agreement in the measured particle size distributions and concentration. The behaviour observed in experimental studies agrees well with theoretical predictions.

Measurements of Humidity and Temperature in the Marine Environment during the HEXOS Main Experiment

Accurate measurement of fluctuations in temperature and humidity are needed for determination of the surface evaporation rate and the air-sea sensible heat flux using either the eddy correlation or inertial dissipation method for flux calculations. These measurements are difficult to make over the ocean, and are subject to large errors when sensors are exposed to marine air containing spray droplets. All currently available commercial measurement devices for atmospheric humidity require frequent maintenance. Included in the objectives of the Humidity Exchange over the Sea program were testing and comparison of sensors used for measuring both the fluctuating and mean humidity in the marine atmosphere at high wind speeds and development of techniques for the protection of these sensors against contamination by oceanic aerosols. These sensors and droplet removal techniques are described and comparisons between measurements from several different systems are discussed in this paper. To accomplish these goals, participating groups devised and tested three methods of removing sea spray from the sample airstream. The best performance was given by a rotating semen device, the “spray Ringer.” Several high-frequency temperature and humidity instruments, based on different physical principles, were used in the collaborative field experiment. Temperature and humidity fluctuations were measured with sufficient accuracy inside the spray removal devices using Lyman-α hygrometers and a fast thermocouple psychrometer. Comparison of several types of psychrometers (using electric thermometers) and a Rotronic MP-100 humidity sensor for measuring the mean humidity illustrated the hysteresis of the Rotronic MP-100 device after periods of high relative humidity. Confidence in the readings of the electronic psychrometer was established by in situ calibration with repeated and careful readings of ordinary hand-held Assman psychrometers (based on mercury thermometers). Electronic psychrometer employing platinum resistance thermometers perform very well.

In‐Line Particle Size Determination for Jet Agglomeration Processes

AbstractIn jet agglomeration plants, powders are agglomerated to obtain good instant properties. The free‐falling initial material is wetted in a spray cone by droplets or in a steam jet by condensation at the particle surface. In a subsequent region of high particle concentration, collision between particles occurs and agglomerates form, if the forces of adhesion are strong enough. A commercial measurement device, working according to the principle of Fraunhofer diffraction, was modified for in‐line application. It was used to measure particle size distributions and concentrations of solid particles and droplets in jets. A model is presented to calculate local particle sizes by means of mass balances from integral measurements over large volumes. The results of in‐line particle size and agglomerate size analyses show the practical importance of dry agglomeration during transport and lead to a better understanding of the subsequent wet agglomeration process.