Test Partition Research Articles

An allometric prior enhances acoustic niche partitioning signal.

The acoustic niche hypothesis suggests that vocal signals of sympatric animal species are structured so as to minimize acoustic interference and facilitate communication. Accordingly, each species attempts to establish its own acoustic bandwidth so that intra-species signals are not masked. Detecting a non-random partitioning of the frequency spectrum among sympatric species could constitute evidence for the existence of acoustic avoidance behaviour. However, results from previous studies have been mixed or inconclusive, possibly as a consequence of overlooking the importance of physiological and ecological constraints. Here we introduce an improved test that incorporates prior information on body mass to account for the allometric correlation between mass (size) and vocalization frequency. By correcting for the bias induced by this correlation, the new test uncovers evidence of acoustic niche partitioning as a function of frequency in several tropical bird communities that would not be detected under a more standard test. Separately, we introduce a spatial version of the acoustic partitioning test which, in theory, could prove effective when data are collected from multiple sites located in close spatial proximity.

Dysmetabolisms Can Affect Total Antioxidant Capacity (TAC) of Human Plasma: Determination of Reference Intervals of TAC by Way of CUPRAC-BCS Method.

The total antioxidant capacity (TAC) of human plasma is an index of the redox buffer capacity of this biological fluid and could be a biomarker for those disorders affecting redox status. Distinguishing physiological from pathological conditions needs a reference. Therefore, this work aims to define the reference intervals for TAC of human plasma of apparently healthy adult individuals. TAC was measured using the CUPRAC-BCS (CUPric reducing antioxidant capacity-bathocuproinedisulfonic acid) method previously optimized and tested in a clinical laboratory. A population of 500 blood donors was selected, plus an additional 222 pathological patients carrying specific defective metabolisms, namely, hyperuricemia, hyperbilirubinemia, and type 2 diabetic mellitus. The reference intervals of TAC were calculated according to international guidelines. Due to the response of a partitioning test, the reference intervals for healthy population were separately defined for male (258) and female (151) groups. The reference intervals (µmol L−1) resulted: 727–1248 for the male subgroup and 637–1048 for the female subgroup. The absence of an age effect on TAC values was verified. The reference intervals evaluated allow a discussion on some pathological conditions overloading the plasma with redox-active waste substances.

Integrating baseline MR imaging biomarkers into BCLC and CLIP improves overall survival prediction of patients with hepatocellular carcinoma (HCC).

We aimed to evaluate the independent predictive role of baseline imaging biomarkers for overall survival (OS) and transplant-free survival (TFS) in patients with HCC and assess the incremental value of these biomarkers to current staging systems. In this retrospective IRB approved study, the clinical, laboratory, and imaging parameters of 304 HCC patients were collected. Cox regression model was utilized to identify the potential predictors of survival. Recursive partitioning test was utilized to identify the optimal ADC cutoff for stratifying patients' OS. Patients were stratified based on Barcelona Clinic Liver Cancer (BCLC) and Cancer of the Liver Italian Program (CLIP). Binary ADC value (above vs. below the cutoff) and tumor margin (well- vs. ill-defined) were integrated into BCLC and CLIP. OS and TFS was compared for patients based on standard criteria with and without imaging biomarkers. At baseline, patients with low tumor ADC and well-defined tumor margin (favorable imaging biomarkers) had longer survival, as compared to those with high ADC and ill-defined tumor margin (unfavorable imaging biomarkers) (median OS of 43months vs. 7months, respectively) (p < 0.001). Tumor ADC and tumor margin remained strong independent predictors of survival after adjustment for demographics, BCLC and CLIP staging, and tumor burden. Incorporating ADC and tumor margin improved performance of OS prediction by 9% in BCLC group and 6% in CLIP group. Incorporating ADC and tumor margin to current staging systems for HCC significantly improve prediction of OS and TFS of these criteria. • ADC and tumor margin are predictors of overall survival in HCC patients, independent of clinical, laboratory, and other imaging variables. • Adding ADC and tumor margin improved the prognostic value of BCLC and CLIP criteria by 9% and 6%, respectively. • High ADC and ill-defined tumor margin at baseline predicted poor survival, regardless of patient's liver function and general health status.

Pengujian Black Box pada Aplikasi Perpustakaan Berbasis Web Menggunakan Teknik Equivalence Partitioning

In determining the level of quality of a software it is necessary to test the software. Tests tested can include specifications, design, and coding of the software. This test is conducted to test web-based library software. This test uses the Black Box Testing method using the Equivalence Partitioning technique. Black Box Testing is applied in order to find errors in software related to erroneous functions, errors in interface display, data structure errors or access rights in external databases, sub-optimal performance in a process, and errors in initialization or termination. The Equivalence Partitioning technique defines the cases to be tested by finding some errors and minimizing the number of cases that must be made. The Equivalence Partitioning test case design is based on the premise of the input and output of a component which is partitioned into classes according to the specifications of that component, which are treated equally (equivalence). It can also be assumed that the results of an input produce the same response. The expected result of testing this software is to ensure that this software is free from errors so that in its use there will be no obstacles that prevent the user from doing his work. And inform that the software is in accordance with predetermined specifications.

Pengujian Black Box pada Aplikasi Admin PT. World Trans Berbasis Web Menggunakan Metode Equivalence Partitioning

Admin Application PT. World Trans which is being developed, found a problem in the database system that failed to communicate with the application system, namely when the admin enters the application using a user name and password, the database does not respond to data calls that are being made and the admin cannot enter the application. The development team has made improvements, and this time the test was carried out in an effort to see the possibility of the same defects or new defects in the application. So, if not tested, it will be very detrimental for business owners and other users. This test uses the Black Box testing technique. Black Box testing method consists of several ways, including Equivalence Partitioning, Boundary Value Analysis, Comparison Testing, Sample Testing, Robustness Testing, and others. Among the many testing methodologies, this test method was chosen using Equivalence Partitioning. Because Equivalence Partitioning is a Black Box testing method that breaks or divides the input domains of the program into data classes so that a test case can be obtained. The design of the Equivalence Partitioning test case is based on evaluating the equivalence class for input conditions that describe a set of conditions that are true or not. The results of this test are the admin application system PT. World Trans can make data calls to the database and there are no problems as before or new problems so that the system can run properly and according to software requirements that have been determined. With the results of this test, the development team can find out the extent of the problem in this application, as well as see the possibility of similar or new problems that can harm the team and business owners.

Experimental Investigation of Surfactant Partitioning in Pre-CMC and Post-CMC Regimes for Enhanced Oil Recovery Application

The applications of surfactants in Enhanced Oil Recovery (EOR) have received more attention in the past decade due to their ability to enhance microscopic sweep efficiency by reducing oil-water interfacial tension in order to mobilize trapped oil. Surfactants can partition in both water and oil systems depending on their solubility in both phases. The partitioning coefficient (Kp) is a key parameter when it comes to describing the ratio between the concentration of the surfactant in the oil phase and the water phase at equilibrium. In this paper, surfactant partitioning of the nonionic surfactant Alkylpolyglucoside (APG) was investigated in pre-critical micelle concentration (CMC) and post-cmc regimes at 80 °C to 106 °C. The Kp was then obtained by measuring the surfactant concentration after equilibration with oil in pre-cmc and post-cmc regimes, which was done using surface tension measurements and high-performance liquid chromatography (HPLC), respectively. Surface tension (ST) and interfacial tension (IFT) behaviors were investigated by performing pendant and spinning drop tests, respectively—both tests were conducted at high temperatures. From this study, it was found that APG was able to lower IFT as well as ST between water/oil and air/oil, and its effect was found to be more profound at high temperature. The partitioning test results for APG in pre-cmc and post-cmc regimes were found to be dependent on the surfactant concentration and temperature. The partitioning coefficient is directly proportional to IFT, where at high partitioning intensity, IFT was found to be very low and vice versa at low partitioning intensity. The effect of temperature on the partitioning in pre-cmc and post-cmc regimes had the same impact, where at a high temperature, additional partitioned surfactant molecules arise at the water-oil interface as the association of molecules becomes easier.

SISTEM INFORMASI MOBILE ASSISTANT MAHASISWA JURUSAN SISTEM INFORMASI FAKULTAS KOMPUTER UNIVERSITAS POTENSI UTAMA BERBASIS ANDROID

Sudah menjadi suatu kebiasaan jika mahasiswa masih sering tidak tepat waktu dalam menghadiri kegiatan perkuliahan, selain itu mahasiswa juga sering lupa untuk mengerjakan tugas atau mempersiapkan diri untuk menghadapi ujian. Hal ini berdampak pada pencapaian nilai yang diperoleh tidak menjadi maksimal. Dalam penelitian ini, peneliti membangun sebuah Sistem Informasi mobile pada smartphone berbasis Android sebagai pengingat bagi mahasiswa Jurusan Sistem Informasi Fakultas Komputer Universitas Potensi Utama. Aplikasi ini terdiri dari dua bagian yaitu berbasis Web untuk admin dan berbasis Android untuk pengguna yang terhubung menggunakan Web Service. Aplikasi ini dibuat agar dapat menunjang dan memaksimalkan kegiatan perkuliahan. Aplikasi ini adalah sebagai alarm pengingat mahasiswa agar mereka selalu ingat akan jadwal perkuliahan, jadwal pengumpulan tugas, dan jadwal pelaksaan ujian. Sistem Informasi ini juga dilakukan pengujian agar mendapatkan hasil yang diinginkan dengan menggunakan metode pengujian Black-Box Equivalence Partitioning. Hasil dari pengujian Black-Box Equivalence Partitioning menunjukkan sistem dapat berjalan sesuai dengan yang diharapkan.

Thermal-aware SoC Test Scheduling with Voltage/Frequency Scaling and Test Partition

With increasing power density in modern integrated circuits, thermal issues are becoming a critical problem in System-on-a-Chip (SoC) testing. In this paper, we develop the thermal-aware test scheduling methods using Voltage/Frequency Scaling (VFS) and Test Partition (TP) to reduce the expensive Test Application Time (TAT). First, we develop a quick temperature estimation method in test scheduling to ensure the test temperature within the given range. Second, we propose a thermal-aware test scheduling method based on the mixed-integer linear programming model (MILP) (called STP-M) that applies VFS and TP to search the optimum scheduling and further reduce the TAT. Third, we develop a heuristic method based on Rectangular Strip Packing (called H-RSP) to quickly access the quasi-optimal scheduling. The experimental results on ITC’02 benchmarks showed that the STP-M obtains the most optimized result for every benchmark and saved 15.5% and 8.0% TAT on average compared with the existing works, while H-RSP takes less than 10 seconds to access the quasi-optimal scheduling that is close to that of STP-M.

Maintaining of low Doppler shifts in cetaceans as strategy to avoid predation

Cetaceans are widely diversified in their sonometric characteristics but no comparative research has determined the general patterns that condition their bio-acoustic evolution across a large number of species. Echolocation calls of 69 cetaceans species has been obtained from different data sources. Through analysis by a Hierarchical Partitioning test, a non-parametric substitute of variance analysis, the absence of statistical differences between bioacoustic data sources has been demonstrated. Sounds were normalized and the fundamental frequency of each species was determined by autocorrelation. Also, the average swimming speed of each species was obtained from published papers. Finally, the intensity of the Doppler effect was calculated for each species using the mathematical equation of underwater sound physics. Doppler shifts lower than 160Hz were found for the majority of species. This can be explained as a behavioral strategy to avoid depredation by Killer Whales. Only certain species of Ziphidae (genus Mesoplodon, Indopacetus pacificus and Ziphius cavirostris) and six species of Delphinidae (from Lagenorhynchus and Cephalorhynchus genus) present higher Doppler shifts. These species had found other strategies to avoid depredation such as the use of echolocation only in deep waters, very high average swimming speeds, large flocks or the use of very high frequencies. From these results it is possible to conclude that depredation conditions all the evolution of echolocation signals of cetaceans except in a reduced number of species that had developed different behavioral strategies to escape from Killer Whales.

Impact of Food-Related Environmental Factors on the Adherence and Biofilm Formation of Natural Staphylococcus aureus Isolates

Staphylococcus aureus is a pathogenic bacterium capable of developing biofilms on food-processing surfaces, a pathway leading to cross contamination of foods. The purpose of this study was to investigate the influence of environmental stress factors found during seafood production on the adhesion and biofilm-forming properties of S. aureus. Adhesion and biofilm assays were performed on 26 S. aureus isolated from seafood and two S. aureus reference strains (ATCC 6538 and ATCC 43300). Cell surface properties were evaluated by affinity measurements to solvents in a partitioning test, while adhesion and biofilm assays were performed in polystyrene microplates under different stress conditions of temperature, osmolarity, and nutrient content. The expression of genes implicated in the regulation of biofilm formation (icaA, rbf and σ( B )) was analyzed by reverse transcription and quantitative real time PCR. In general, S. aureus isolates showed moderate hydrophobic properties and a marked Lewis-base character. Initial adhesion to polystyrene was positively correlated with the ionic strength of the growth medium. Most of the strains had a higher biofilm production at 37°C than at 25°C, promoted by the addition of glucose, whereas NaCl and MgCl(2) had a lower impact markedly affected by incubation temperatures. Principal Component Analysis revealed a considerable variability in adhesion and biofilm-forming properties between S. aureus isolates. Transcriptional analysis also indicated variations in gene expression between three characteristic isolates under different environmental conditions. These results suggested that the prevalence of S. aureus strains on food-processing surfaces is above all conditioned by the ability to adapt to the environmental stress conditions present during food production. These findings are relevant for food safety and may be of importance when choosing the safest environmental conditions and material during processing, packaging, and storage of seafood products.

Confirming Testlet Effects

A testlet is a cluster of items that share a common passage, scenario, or other context. These items might measure something in common beyond the trait measured by the test as a whole; if so, the model for the item responses should allow for this testlet trait. But modeling testlet effects that are negligible makes the model unnecessarily complicated and risks capitalization on chance, increasing the error in parameter estimates. Checking each testlet to see if the items within the testlet share something beyond the primary trait could therefore be useful. This study included (a) comparison between a model with no testlets and a model with testlet g, (b) comparison between a model with all suspected testlets and a model with all suspected testlets except testlet g, and (c) a test of essential unidimensionality. Overall, Comparison b was most useful for detecting testlet effects. Model comparisons based on information criteria, specifically the sample-size adjusted Bayesian Information Criteria (SSA-BIC) and BIC, resulted in fewer false alarms than statistical significance tests. The test of essential unidimensionality had true hit rates and false alarm rates similar to the SSA-BIC when the testlet effect was zero for all testlets except the studied testlet. But the presence of additional testlet effects in the partitioning test led to higher false alarm rates for the test of essential unidimensionality.

TFT-LCD Mura Defects Using Independent Component Analysis

Independent component analysis (ICA) is used to detect the mura regions with varying sizes and brightness levels before thresholding, then individually analyzed the mura regions in order to avoid unnecessary background effect. Defects detection is performed by partitioning test image into overlapping sub-windows and Classifying each sub-window as normal or mura region by comparing the difference of spatial distance between ICs of defective and non-defective. During the experimental process, a median filter and a high-pass filter are also respectively used to filter out the noise and enhance mura gray intensity. In this research, we developed ICA to achieve off-line learning and on-line detection.

Surface physicochemical analysis of natural Lactococcus lactis strains reveals the existence of hydrophobic and low charged strains with altered adhesive properties

The cell surface physicochemical properties of 50 Lactococcus lactis strains of different subspecies and isolated from different origins (dairy, vegetal and animal) were examined. Cell surface hydrophobicity and Lewis acid–base properties were evaluated by affinity measurements to solvents in a partitioning test, while the global electrical charge of the cells was assessed by micro-electrophoresis using a laser zeta-meter. A global multivariate analysis of the results revealed a high natural diversity of L. lactis cell surface properties. While 52% of the strains present a hydrophilic and electronegative cell wall surface, a group of strikingly hydrophobic strains (12% of the strains) and a group of strains with unusual low charged surface (18%) were identified. Adhesion on polystyrene microtitre plates was evaluated for twelve strains selected from the multivariate analysis as representatives of the various observed cell wall surface physicochemical patterns. A significant correlation between adhesion, hydrophobicity and low electronegativity was observed when adhesion was performed in a low ionic strength suspending medium. The most adhesive strains were hydrophobic or low charged. The presence of repulsive electrostatic interactions led to a decrease in adhesion of the most negatively charged hydrophilic strains. The present study highlights the diversity of L. lactis cell surface physicochemical properties, diversity that could not be connected to the origin or to the subspecies of the strains.

Partitioning of chemicals—important factors in exposure assessment of offshore discharges

The CHARM ( chemical hazard assessment and risk management) model was developed to give operators, chemical suppliers, and environmental authorities a scientific framework for analyzing the environmental hazard and risk of offshore chemicals used and discharged to the marine environment. This paper presents results from an R and D project carried out on partitioning of typical offshore chemicals where the objective was to validate the partitioning algorithms in CHARM. The work included further development and verification of the HPLC (OECD 117) method for determining oil/water partitioning, or fraction released of production chemicals, for evaluation of the applicability of the Shake Flask method (OECD 107) and modification of the sediment/water partitioning test methods, as well as establishment of a calculation method for determining the weighted average log P ow for chemical mixtures of homologs. The calculation method was recommended adopted in CHARM. Based on the experimental partitioning results, the CHARM partitioning algorithms were evaluated. The test results showed that the HPLC technique is a “robust” method for determining the P ow, but has limitations for surfactants and chemicals with high log P ow-values, which are typical offshore chemicals. The traditional correlations reported between P ow, the BCF, the fraction of a chemical released with produced water, and the P sw is not valid for typical surfactants. Another approach is therefore used in CHARM, which also was evaluated in this project. There is, however, a need for further validation of the CHARM partitioning algorithms.

Using New Proximity Measures With Hierarchical Cluster Analysis to Detect Multidimensionality

A new approach for partitioning test items into dimensionally distinct item clusters is introduced. The core of the approach is a new item‐pair conditional‐covariance‐based proximity measure that can be used with hierarchical cluster analysis. An extensive simulation study designed to test the limits of the approach indicates that when approximate simple structure holds, the procedure can correctly partition the test into dimensionally homogeneous item clusters even for very high correlations between the latent dimensions. In particular, the procedure can correctly classify (on average) over 90% of the items for correlations as high as .9. The cooperative role that the procedure can play when used in conjunction with other dimensionality assessment procedures is discussed.

Assessment of three way interaction in 2 × J × K tables

The power of a test for no three way interaction in 2 × J × K tables, performed by partitioning the K strata into two groups was investigated by simulation. Mantel-Haenszel estimation techniques were used to calculate the test statistic. The power was compared with that of Pearson's X 2 and the likelihood ratio G 2. The partition test had substantially greater power than either X 2 or G 2 in cases most favorable to the partition test and somewhat greater power for cases moderately favorable to it. The greater power can be explained by the smaller degrees of freedom for the partition test ( J − 1 vs ( J − 1)( K − 1) for X 2 and G 2). The results also suggest that the distribution of the test statistic more closely follows a non-central chi square distribution in non-null cases for the partition test. If an appropriate partitioning of the strata can be made, the partitioning test would be preferable to the widely used X 2 and G 2 tests.

Recent Developments in Design Automation

In this paper we review some of the recent developments in the automated design and analysis of digital systems. The areas of gate level simulation, synthesis, partitioning, interconnection and fault test generation are discussed, and new algorithms in each of these areas are presented and compared.