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Maternal control is a major dimension of parenting and has different meanings, practices, and potential consequences across cultures. The present study aimed to identify and compare mothers' conceptualizations of parenting control across four cultures to reveal a more nuanced understanding regarding the meaning and practices of control: European American, Chinese immigrant. Korean immigrant, and Turkish. Using a semistructured open-ended interview, 100 European American, 102 U.S. Chinese immigrant, 103 U.S. Korean immigrant, and 109 Turkish mothers of preschool-aged children reported the ratings of importance, specific reasons, and strategies for exerting control over their children in daily life. Results revealed both shared and unique conceptualizations of maternal control across four cultures. Specifically, all mothers reported that it is important to express maternal control over their children in order to set behavioral norms/standards, maintain child safety, support social relations and respect for others, provide guidance, and guide moral development. Moreover, mothers discussed utilizing nonphysical punishment, setting and maintaining rules, reasoning/negotiating. consistency, physical punishment and verbal control, showing parents' serious/stern attitude, correction. and psychological control forms of control. However, the levels at which mothers emphasize the different reasons and strategies varied across cultures, reflecting culturally emphasized values. The findings of the present study further enrich our understanding of the complexities of maternal control across cultures., Foundation for Child Development and the National Institute of Child Health and Human Development; Koç University

In this research, the effect of carbon nanotube (CNT) addition on the structural and superconducting properties of Bi2Sr2CaCu2Oy + x wt% CNT materials with x = 0, 0.5, 1, and 3 prepared by solid state method, followed by directional grown using the laser floating zone (LFZ) technique has been investigated. XRD measurements showed that all samples are composed of almost single Bi-2212 phase. SEM images proved that Bi-2212 phase is the major one, with minor amounts of (Sr,Ca)3BiOx, and Bi-2201 secondary phases. According to the magnetic results, carbon nanotubes decrease Tc values and significantly reduce the magnetic hysteresis loops area and the magnetic critical current density.

Child- and family-related factors that predict internalizing symptoms are under-studied in preschool years and have a negative influence on children’s functioning. We examined observational assessments of preschoolers’ temperamental fear fulness and exuberance, mother reports of negative control, warmth, and parenting stress in a sample of 109 Turkish preschoolers. High temperamental fearfulness and low joyful/exuberant positive affectivity in addition to low warmth and high parenting stress had significant effects on internalizing symptoms. Parenting stress had both direct and indirect relations to internalizing symptoms via lower maternal warmth. When comorbid elevations in externalizing symptoms were controlled, the results were consistent with the interpretation that poor parenting practices and stress associated with the parenting role predict maladaptation in general but that the specific form of maladaptation may be best predicted by individual differences in children’s temperament, Scientific and Technological Research Council of Turkey (TÜBİTAK)

The importance is discussed of the abrasion resistance of dimension stone in applications such as cladding, flooring and paving. Laboratory three-body abrasion tests were carried out on 11 carbonate rocks from the Isparta region in Turkey comprising limestone, marble or travertine. The results showed that the abrasion rate increased linearly with distance, as predicted by the Archard equation. The limestones and marbles were more abrasion-resistant than the travertines, and the more abrasion-resistant rocks tended to have high bulk density, compressive strength, tensile strength and hardness and low porosity. There was a strong correlation between the abrasion rate and the tensile strength, hardness, compressive strength and bulk density of the rocks., The importance is discussed of the abrasion resistance of dimension stone in applications such as cladding, flooring and paving. Laboratory three-body abrasion tests were carried out on 11 carbonate rocks from the Isparta region in Turkey comprising limestone, marble or travertine. The results showed that the abrasion rate increased linearly with distance, as predicted by the Archard equation. The limestones and marbles were more abrasion-resistant than the travertines, and the more abrasion-resistant rocks tended to have high bulk density, compressive strength, tensile strength and hardness and low porosity. There was a strong correlation between the abrasion rate and the tensile strength, hardness, compressive strength and bulk density of the rocks.

The paper presents a time domain model of a heaving buoy wave-energy converter and investigates the tuning problem in irregular seas. The tuning issue is addressed by employing both fixed (passive) and adaptive (active) power-take-off settings. The fixed power-take-off tuning approach includes models based on tuning the device natural frequency to either the energy frequency or peak frequency of the sea-state or a weighted average of several peak frequencies. The adaptive tuning approaches employ a sliding discrete Fourier transform frequency analysis, or a time-series analysis of the measured wave elevation and device velocity to estimate a localized dominant wave frequency and hence calculate power-take-off settings. The paper presents details of these tuning techniques by discussing issues related to the modelling, simulation, and predicted power captures for each method. A comparative study of each method along with practical implications of the results and recommendations are also presented.

The paper presents a time domain model of a heaving buoy wave-energy converter and investigates the tuning problem in irregular seas. The tuning issue is addressed by employing both fixed (passive) and adaptive (active) power-take-off settings. The fixed power-take-off tuning approach includes models based on tuning the device natural frequency to either the energy frequency or peak frequency of the sea-state or a weighted average of several peak frequencies. The adaptive tuning approaches employ a sliding discrete Fourier transform frequency analysis, or a time-series analysis of the measured wave elevation and device velocity to estimate a localized dominant wave frequency and hence calculate power-take-off settings. The paper presents details of these tuning techniques by discussing issues related to the modelling, simulation, and predicted power captures for each method. A comparative study of each method along with practical implications of the results and recommendations are also presented.

It is well known that the performance of point-absorber wave energy converters (WECs) depends upon resonance with the wave frequency. Indeed, the ideal performance of a resonating point-absorber WEC in a regular sea that can be represented by a simple sinusoid is well known, provided all motions are small and remain in the linear region. However, the performance of such a device in a more realistic, irregular sea that is not represented by a simple sinusoid cannot be so readily calculated. The first difficulty lies in modelling the hydrodynamic behaviour of the device. Recent developments in representing the hydrodynamic diffraction and radiation forces have enabled relatively simple simulation models to be developed, such as those presented and used in this paper. The second difficulty lies in the design of the device itself. In a regular sea with a known wave frequency, the settings of the power take-off system can be defined at well-known optimum values. It is shown in the present paper that, even when the wave frequency is not constant, the local wave frequency can be estimated, and this estimate can be used to adjust the power take-off system settings to maintain quasiresonance and, hence, approach the level of performance in a comparable regular sea. In this manner, for irregular seas it is possible to identify a dominant wave frequency over a relatively short time period and to use this frequency continuously to adjust the power take-off system settings, so as to adapt to the current sea conditions. This is likely, in some sea conditions, to involve the power take-off supplying power over part of the cycle, rather than absorbing it. This will increase the demands placed on the power take-off - particularly on its efficiency when the direction of power flow has to be reversible. The relative performance of such a tuneable point-absorber WEC is assessed in the paper. It is shown that the power converted in irregular seas could be as much as 50 per cent of the r

It is well known that the performance of point-absorber wave energy converters (WECs) depends upon resonance with the wave frequency. Indeed, the ideal performance of a resonating point-absorber WEC in a regular sea that can be represented by a simple sinusoid is well known, provided all motions are small and remain in the linear region. However, the performance of such a device in a more realistic, irregular sea that is not represented by a simple sinusoid cannot be so readily calculated. The first difficulty lies in modelling the hydrodynamic behaviour of the device. Recent developments in representing the hydrodynamic diffraction and radiation forces have enabled relatively simple simulation models to be developed, such as those presented and used in this paper. The second difficulty lies in the design of the device itself. In a regular sea with a known wave frequency, the settings of the power take-off system can be defined at well-known optimum values. It is shown in the present paper that, even when the wave frequency is not constant, the local wave frequency can be estimated, and this estimate can be used to adjust the power take-off system settings to maintain quasiresonance and, hence, approach the level of performance in a comparable regular sea. In this manner, for irregular seas it is possible to identify a dominant wave frequency over a relatively short time period and to use this frequency continuously to adjust the power take-off system settings, so as to adapt to the current sea conditions. This is likely, in some sea conditions, to involve the power take-off supplying power over part of the cycle, rather than absorbing it. This will increase the demands placed on the power take-off - particularly on its efficiency when the direction of power flow has to be reversible. The relative performance of such a tuneable point-absorber WEC is assessed in the paper. It is shown that the power converted in irregular seas could be as much as 50 per cent of the r

A detailed analysis and comparison of various control architectures is presented in order to meet the challenging design requirements targeted. All the present advanced control systems have certain advantages and disadvantages compared with each other. Due to the lack of an optimal control system with desired capabilities, such a control system has been the focus of recent robotics research programs. The new approach proposed in this paper is a hybrid control system that takes the advantages of various control structure types thereby integrating them in a way that results in an overall increase in synergy. The proposed control architecture presents a new approach to the design of supervisory control system that utilizes reactive, deliberative, distributed and centralised control approaches, and uses fuzzy logic as well as modular hierarchical structure. The architecture carries out supervision, modification and execution of commands generated by the centralised command arbitration module by conducting fuzzy logic integration of activated behaviours from distributed, independent asynchronous decision making processes that takes information from the user, sensory system and task description, thus providing goal-oriented, real-time responsive and tele-operable control system architecture. The resulting control system was experimented on and it was observed that not only was the response time sufficiently short, but also it exhibited robustness, flexibility, adaptability, portability and expandability.

Driving a supply gate in the presumed low-stress zone adjacent to the loader gate of an excavator panel led to an extensive roof fall at Bilsthorpe colliery, UK, in 1993 and left a question-mark over the use of skin-to-skin drives supported mainly by rock bolting. Physical and numerical models have demonstrated the potential danger of the working method. A shear failure plane developed from the rib edge into roof strata of the loader gate and another at the abutment side of the supply gate, exposing it to the fall of large blocks of rock. Modelling showed that the roof fall was due not to the inability of the rock bolts to prevent bed separation but to a method of working that made the bolts ineffective due to the height of the block delineated by the shear failure planes. Further modelling found that a 7.5 m or 10 m wide pillar would have prevented development of the failure zones, whereas a 5 m pillar was undersized., Driving a supply gate in the presumed low-stress zone adjacent to the loader gate of an excavator panel led to an extensive roof fall at Bilsthorpe colliery, UK, in 1993 and left a question-mark over the use of skin-to-skin drives supported mainly by rock bolting. Physical and numerical models have demonstrated the potential danger of the working method. A shear failure plane developed from the rib edge into roof strata of the loader gate and another at the abutment side of the supply gate, exposing it to the fall of large blocks of rock. Modelling showed that the roof fall was due not to the inability of the rock bolts to prevent bed separation but to a method of working that made the bolts ineffective due to the height of the block delineated by the shear failure planes. Further modelling found that a 7.5 m or 10 m wide pillar would have prevented development of the failure zones, whereas a 5 m pillar was undersized.

The inaccessibility of waste areas makes it hard to measure deformation and stresses in goaf, which need to be known for calculating the safe width of barrier pillars. A method is proposed for estimating the distance behind the face at which the goaf returns to cover pressure and the stress distribution in the goaf of flat-lying longwall panels where caving is bulk-controlled. It has been found that cover pressure distance increases exponentially with increasing depth. For a constant depth and mining height, cover pressure distance increases if the bulking factor of the rock pile increases or the strength of the rock fragments decreases. When the mining height increases, the bulking factor of the rock pile also increases and hence so does the cover pressure distance. A six-parameter Taylor series polynomial function is used to estimate stress distribution curves, whose general form is verified with curves obtained through numerical models., The inaccessibility of waste areas makes it hard to measure deformation and stresses in goaf, which need to be known for calculating the safe width of barrier pillars. A method is proposed for estimating the distance behind the face at which the goaf returns to cover pressure and the stress distribution in the goaf of flat-lying longwall panels where caving is bulk-controlled. It has been found that cover pressure distance increases exponentially with increasing depth. For a constant depth and mining height, cover pressure distance increases if the bulking factor of the rock pile increases or the strength of the rock fragments decreases. When the mining height increases, the bulking factor of the rock pile also increases and hence so does the cover pressure distance. A six-parameter Taylor series polynomial function is used to estimate stress distribution curves, whose general form is verified with curves obtained through numerical models.

A laboratory study showed that the most important factors influencing the properties of material used to model underground structures are the amount of water added to the mix and the curing conditions over the sand/plaster ratio. Excessive water increased porosity and strain at failure and decreased the material's compressive and tensile strength and its modulus ratio. Strength and elastic properties were controlled by the curing process: curing at low temperature produced material within the average modulus ratio range of 290 to 432 while curing at high temperature produced material with modulus ratios ranging from 64 to 140, depending on composition. Shear tests showed that increasing the ratio of sand to plaster increases friction angle and decreases cohesion. Material cured at a low temperature satisfactorily simulated the properties of Bilsthorpe Colliery rocks., A laboratory study showed that the most important factors influencing the properties of material used to model underground structures are the amount of water added to the mix and the curing conditions over the sand/plaster ratio. Excessive water increased porosity and strain at failure and decreased the material's compressive and tensile strength and its modulus ratio. Strength and elastic properties were controlled by the curing process: curing at low temperature produced material within the average modulus ratio range of 290 to 432 while curing at high temperature produced material with modulus ratios ranging from 64 to 140, depending on composition. Shear tests showed that increasing the ratio of sand to plaster increases friction angle and decreases cohesion. Material cured at a low temperature satisfactorily simulated the properties of Bilsthorpe Colliery rocks.