Experimental Design

Traditionally, the American child welfare system intervenes in cases of evident and severe maltreatment. Families in need of help, but who have not reached a crisis, are excluded from typical services. Some suggest that if these families were served, few would be rereferred to the child welfare system. California’s Differential Response (DR) has three tracks, of which ‘‘Track 1’’ targets families screened out of child protective services (CPS) and refers them to agencies that provide voluntary, home-based services and referrals. This study examined child-welfare trajectories for families receiving Track 1 DR services in one California county. Using survival analysis, treatment group children (N = 134) were compared to children eligible for services but denied due to program capacity (comparison group N = 511). Findings suggest no statistically significant differences between groups on the likelihood of a re-report following program participation, timing of maltreatment reports, or r...

Modern membrane technologies are useful for enhancing the concentration of phenolic antioxidants in olive mill waste water (OMWW) to produce concentrates with valuable applications in functional foods. Three types of OMWW concentrates, each with different levels of solute concentration and purity, were obtained from a single OMWW batch and dissolved in two extra virgin olive oils to achieve saturated solutions. Three addition levels were considered. Accelerated aging testing of the oils was performed at 60 °C and the samples were analyzed after two, four, and 6 weeks of aging. D-optimal design was used to select the 26 experiments that allowed the evaluation of the influence of the different variables on oil stability. The addition of OMWW concentrates resulted in a significant increase in the Radical Scavenging Activity (RSA) of the olive oils. Under these mild experimental conditions, the moderate formation of fatty acid hydroperoxides was probably masked by interfering compounds.

Building type explores interpretation as a creative strategy for developing experimental design processes that translate architecture into type. The research sits within the experimental area of the contemporary type design context. The methodology is based on a hermeneutic framework and establishes a cycle of research methods that enable the project to progress through several phases of inquiry. It is a practice-based project, but its intended outputs are not fully resolved typefaces, but rather a range of experimental type design strategies. These strategies translate aspects of selected New Zealand suburban architecture (a single-bay villa, a Californian bungalow and a state house) into letterforms and prototypefaces. The outcomes are communicated through two sets of publications, large format posters, plan print guidelines, card inserts and an exegesis.

This paper aims at developing a regression residual control chart to economically detect the abnormal patterns of the stencil printing process (SPP), so as to predict significant deviations that might result in nonconforming products. The SPP is widely recognized as the main contributor of soldering defects in a surface mount assembly (SMA). The earlier those abnormal conditions can be detected in the SPP stage, the less expensive the defect correction costs. Shewhart control chart is frequently used to monitor the amount of solder paste volume. However, its results can be error-prone since the solder paste volume is significantly affected by other process factors. For developing the proposed control chart, a 3^8-3 experimental design was first conducted and validated to formulate the relationship between the control variables and the SPP response. Eight process factors for SPP were initially defined, including stencil thickness, component pitch, aperture area, snap-off height, sque...

Evaluating the Performance of Two Drill Seeder at Different Speeds This study aimed to evaluate the de pth and distribution uniformity of maize seeds as a function of two displacement speeds. The work was carried out at the Experimental Nucleus of Agricultural Engineering - NEEA, of the Universidade Estadual do Oeste do Paraná - Cascavel Campus. The soil was classified

An experimental design approach, based on central composite design, has been used to investigate the dependence of accelerated solvent extraction operating variables (pressure, temperature, extraction time) on the recovery of 16 polycyclic aromatic hydrocarbons (PAHs) from native, contaminated soil. At the 95% confidence interval, no significance in terms of the three operating parameters was found when considering the total PAH recovery. However, when individual PAHs were consid-ered, some compounds were found to be dependent on operating variables. The most significant operating vari-able was extraction temperature. Low extraction temper-ature (40 °C) was found to be significant for naphthalene, chrysene, and benzo[b]fluoranthene. Using constant operating conditions (100 °C, 14 MPa and an extraction time of 5 min plus 5 min equilibriation time), the influence of extraction solvent was evaluated. No depen-dence on recovery was found when polar organic solvents, i.e., a dipole momen...

The complex formed by chronic illness, episodes of acute illness, physiological disabilities, functional limitations, and cognitive problems is prevalent among frail elderly persons. These individuals rely on assistance from social and health care programs, which in ...

The extraction and determination of chlorinated biphenyls (CBs) in soils and solid wastes is an ongoing subject of study. This is an overview article that compares the microwave-assisted extraction (MAE) and accelerated solvent extraction (ASE) techniques. The extraction of CBs by ASE has been optimised taking into account the variation of pressure, temperature and extraction time by means of experimental design and the Simplex approach. The recoveries obtained under the optimum conditions are compared and discussed with those obtained from MAE and Soxhlet extractions.

Objective: To develop a method for establishing the presence of command-following in individuals with traumatic brain injury, based on the principles of single-subject experimental design.Design: A series of single-subject experiments, individualized to the particular command-following question about a particular patient.Setting: An inpatient rehabilitation hospital with a specialized program for vegetative and minimally conscious brain injured patients.Patients: Eight individuals with serious

In this paper, a combined use of dimensional analysis (DA) and modern statistical design of experiment (DOE) methodologies is proposed for a hydrodynamics experiment where there are a large number of variables. While DA is well-known, DOE is still unfamiliar to most ocean engineers although it has been shown to be useful in many engineering and non-engineering applications. To introduce

: The purpose of the testing reported herein was to obtain data describing fluid and structural behavior (interaction of fluid on structure and of structure on fluid) in a controlled experiment in a systematic manner. These data are to be used for (a) validation of fluid/structure interaction (FSI) modeling codes and (b) to demonstrate a process for archiving and accessing the data. The approach, which uses two types of models (wing and tethered mass), was to obtain ambient upstream, wall, and downstream static and dynamic fluid pressures for the models in various dynamic conditions.

Recent attention is focused on understanding the genetic basis for individual susceptibility to the development of chronic disease. An emphasis is concentrated on establishing an association be-tween inheritance of polymorphic chemical metab-olizing genes and development of ...

City logistics policies require an understanding of several issues (eg freight distribution context, preferences and relationship among agents) seldom accounted for in current research. Policies run the risk of producing unsatisfactory results because behavioural and contextual aspects are not considered. The acquisition of relevant data is crucial to test hypothesis and forecast agents' reactions to policy changes. Despite recent methodological advances in modelling interactive behaviour the development of apt survey instruments is ...

The effects of plantain starch obtained from the unripe fruit of the plantMusa paradisiaca L. (Musaceae) on the mechanical and disintegration properties of paracetamol tablets have been investigated in comparison with the effects of corn starch BP using a 23 factorial experimental design. The individual and combined effects of nature of starch binder (N), concentration of starch binder (C), and the relative density of tablet (RD) on the tensile strength (TS), brittle fracture index (BFI), and disintegration time (DT) of the tablets were investigated. The ranking of the individual effects on TS was RD>C≫N, on BFI was C≫RD>N and on DT was N>C>RD. The ranking for the interaction effects on TS and DT was N-C≫N-RD>C-RD, while that on BFI was N-C≫C-RD>N-RD. Changing nature of starch from a “low” (plantain starch) to a “high” (corn starch) level, increasing the concentration of starch binding agent from 2.5% to 10.0% wt/wt, and increasing relative density of the tablet from 0.80 to 0.90, led to increase in the values of TS and DT, but a decrease in BFI. Thus, tablets containing plantain starch had lower tensile strength and disintegration time values than those containing corn starch, but showed better ability to reduce the lamination and capping tendency in paracetamol tablet formulation. The interaction between N and C was significantly (P<.001) higher than those between N and RD and between C and RD. There is therefore the need to carefully choose the nature (N) and concentration (C) of starch used as binding agent in tablet formulations to obtain tablets of desired bond strength and disintegration properties. Furthermore, plantain starch could be useful as an alternative binding agent to cornstarch, especially where faster disintegration is required and the problems of lamination and capping are of particular concern.

An optimum experimental design to determine the coefficients of the Extended Taylor's Equation in machining is proposed. The technique is based on the minimisation of the ratio between maximum and minimum singular values of the matrix of sensitivity of the tool life related to the machining parameter variations. This procedure generates the best set of cutting conditions to be used in tool life tests which results in a fast convergence of the coefficients and their confidence intervals. This technique was compared to the commonly used fractional factorial design when face milling AISI 1045 steel with cemented carbide cutting tools. The results showed a considerable reduction in the number of tests required to obtain a reliable equation when the optimum experimental procedure was used when compared to the factorial design.