Mixed Regime Research Articles

Flight regimes recognition in actual operating conditions: A functional data analysis approach

Helicopters need adequate monitoring to prevent dynamic failures from excessively affecting components’ health status, increase the level of safety, and reduce operative costs. Health and Usage Monitoring Systems have been developed to monitor helicopters during their lifetime in the last few decades. Recent works demonstrated that despite analyzing physical components’ behavior over time, tracking the regimes performed during each flight contributes to estimating the aircraft’s health and usage status, paving the way for designing accurate prognostics algorithms. However, today, most regime recognition systems rely on data recorded during certification flights. It follows that the training regimes differ from the ones proposed in the prediction phase, which are acquired during helicopter actual operating conditions. This affects these recognition system performances. Aiming at overcoming this limitation, in this work, we proposed an unsupervised regimes recognition system capable of better handling the actual helicopter usage spectrum. In detail, we proposed a system based on an unsupervised learning paradigm, which leverages a soft-membership classification technique to account even for mixed regimes and transitions. In addition, the system represents data according to functional data analysis theory, which allows for considering the temporal relationship between samples in the classification process, often neglected in state-of-the-art approaches. The proposed system was tested on experimental data, collected by Leonardo Helicopter Division, assessing outstanding capabilities in recognizing correctly standard and mixed regimes and transients. Also, the presented results demonstrate the approach capabilities in paving the way for the definition of new regimes, more consistent with the actual helicopter usage spectrum.

Heart Rate Variability in Healthy Subjects During Monitored, Short-Term Stress Followed by 24-hour Cardiac Monitoring.

Heart Rate Variability (HRV) can be a useful metric to capture meaningful information about heart function. One of the non-linear indices used to analyze HRV, Detrended Fluctuation Analysis (DFA), finds short and long-term correlations in RR intervals to capture quantitative information about variability. This study focuses on the impact of visual and mental stimulation on HRV as expressed via DFA within healthy adults. Visual stimulation can activate the automatic nervous system to directly impact physiological behavior such as heart rate. In this investigation of HRV, 70 participants (21 males) viewed images on a screen followed by a math and recall task. Each viewing segment lasted 2 min and 18 s. The math and memory recall task segment lasted 4 min total. This process was repeated 9 times during which the participants’ electrocardiogram was recorded. 37 participants (12 males) opted in for an additional 24-h Holter recording after the viewing and task segments of the study were complete. Participants were randomly assigned to either a pure (organized image presentation) or mixed (random image presentation) image regime for the viewing portion of the study to investigate the impact of the external environment on HRV. DFA α1 was extracted from the RR intervals. Our findings suggest that DFA α1 can differentiate between the viewing [DFA α1 range from 0.96 (SD = 0.25) to 1.08 (SD = 0.22)] and the task segments [DFA α1 range from 1.17 (SD = 0.21) to 1.26 (SD = 0.25)], p < 0.0006 for all comparisons. However, DFA α1 was not able to distinguish between the two image regimes. During the 24-hour follow up, participants had an average DFA α1 = 1.09 (SD = 0.14). In conclusion, our findings suggest a graded response in DFA during short term stimulation and a responsiveness in participants to adjust physiologically to their external environment expressed through the DFA exponent.

Constructal enhancement of cooling performance of local heating elements with different heat generation rates under free and mixed convection regimes

This study aims to obtain the optimum heat generation rate of local heating elements with different heat generation rates in a vertical duct. Covering free and mixed convection regimes, experimental and numerical studies are conducted. Various values of the modified Grashof and Reynolds numbers are taken into account. The influence of the heat generation rates of local heating elements on temperature of the hot spot, local temperatures, system's global conductance and Nusselt number are presented. It is shown that the heating elements with co-heat generation rates cause a rise in the temperature of the hot spot and reduce the global conductance, and the gradual decrease in the heat generation rates of heating elements improves the system's cooling performance.

Scuffing resistance of polyalphaolefin (PAO)-based nanolubricants with oleic acid (OA) and iron oxide nanoparticles

The development and application of nanolubricants has shown great potential to reduce friction and wear, especially in the automotive field for systems operating under boundary and mixed lubrication regimes. The search for additives that do not attack the environment has motivated the use of nanoparticles, especially metallic oxides, because of their characteristics such as low toxicity, high surface area, high wettability, and easy dispersion. The objective of this work was to evaluate the addition of iron oxide nanoparticles as additive to pure PAO 8 base oil. The nanoparticle action mechanisms, lubrication efficiency, friction, and wear rates were evaluated. The concentration of nanoparticles in the oil and the addition of oleic acid as a dispersing agent were varied. The synthesis of the nanoparticles was done by aqueous precipitation; characterization was performed by XRD, FTIR, Raman and SEM analyses. Tribological tests were performed in a reciprocating tribometer (Plint TE 67) using AISI 1020 prismatic samples and AISI 52100 chrome steel balls of 5 mm diameter. Test conditions resulted in boundary lubrication regime, for a starved contact with limited lubricant supply (0.5 µL). Concentrations of 0.4 and 1.6 wt% of nanoparticles were added to the base oil with and without the presence of oleic acid. Friction coefficient was not sensitive to the presence of nanoparticles, with statistically similar values for all the fluids tested. On the other hand, the presence of nanoparticles increased scuffing resistance and reduced wear rates. The lubricants with nanoparticles proved able to withstand relatively high loads, keeping the friction coefficient low for longer test durations due to the formation of protective tribolayers between the worn surfaces. The addition of nanoparticles reduced wear rates by around 27% when compared to tests using pure PAO 8.

POLITICAL MAP OF THE WORLD: ACTUAL ANALYSIS OF THE MAIN ELEMENTS

Scientific approaches to highlighting the main elements of the political map of the world have been updated. The criteria of the state in the political-geographical context have been considered. The list of the main elements of the political map of the world - states, quasi-states, and non-self-governing territories has been offered. These are those entities that have a territory and borders with varying degrees of control, as well as the political system as one of the subsystems of society with varying degrees of internal and external sovereignty and institutional formation.The state is a territorially organized and politically sovereign society. Based on political and geographical criteria (state territory, borders, population, internal and external sovereignty) and customary approaches in the system of international relations (predominant recognition of sovereignty by UN member states), three types of states have been identified: sovereign states (187 UN member states and UN observer state - Vatican); sovereign states not recognized by one or more states (6 UN member states - Armenia, Israel, North Korea, PRC, Republic of Cyprus, Republic of Korea); sovereign states that de facto do not exist, but are de jure recognized by many states (UN observer state - Palestine). In 2021 the total number of sovereign states is 195.&#x0D; The definition of quasi-states is based on the same criteria, and the typology takes into account in each case the degree and features of the manifestation of these features at the present stage. Quasi-states are countries that have the following characteristics: clear geographical parameters (territory, borders); population characterized by the linguistic, cultural, ethnopolitical, or social community; limited or no external sovereignty; weak domestic political power of the government to lead the country. Six types of quasi-states have been identified: countries whose sovereignty is partially recognized (Kosovo); countries that are de facto sovereign, but de jure not recognized by most states in the world (Taiwan); countries with partial international recognition, but limited control over their territory and lack of internal legitimacy of power (Western Sahara); countries formed as a result of external armed intervention and recognized only by the aggressor state and its geopolitical allies (Abkhazia, South Ossetia, Transnistria, the Turkish Republic of Northern Cyprus); countries that are de facto sovereign, but de jure not recognized by any state in the world (Somaliland); countries without international recognition and with limited control over the territory (Nagorno-Karabakh).&#x0D; Non-self-governing territories are such political-territorial entities that are under the jurisdiction of another state, or on the basis of concluded mutual agreements, another state is entrusted with part of administrative and security functions. These are former colonial possessions that have not yet exercised their right to political self-determination. The degree of dependence on the management area in each case is unique, so it is difficult to distinguish types, and their number is constantly declining.&#x0D; Not-essential elements of the political map of the world are those territories to which the jurisdiction of sovereign states and the rules laid down in international treaties or the first and second at the same time. These are political-territorial formations of hybrid object-subject status: territories with the mixed regime (exclusive (maritime) economic zone and continental shelf); territories with a special regime (international straits, international sea canals, international rivers, and lakes, buffer zones); territories with an international regime (Arctic and Antarctic, high seas, airspace outside state territories, seabed and its subsoil outside exclusive economic zones and the continental shelf, outer space, moon, and other celestial bodies); territories contested by several states.&#x0D; Keywords: political map of the world, state, quasi-state, country, political-territorial formation.

Diverse Physical Processes Drive Upper‐Tail Flood Quantiles in the US Mountain West

AbstractFloods in the mountainous western U.S. typically arise from rainfall, snowmelt, or rain‐on‐snow (ROS). This implies that streamflow records comprise “mixtures” of flood regimes with differing physical characteristics. This runs counter to the assumption, made in flood hazard practice, that flood observations are independent and identically distributed. In this study, we examine 308 watersheds and 281 (91%) of which exhibited substantial roles of at least two flood regimes, with rainfall and ROS accounting for the very largest floods. We demonstrate that flood mixtures can have dramatic impacts on upper‐tail flood quantiles—rarer than the 0.01 annual exceedance probability. While the geographic distribution of mixed flood regimes is explained by climate and elevation, such regimes are subject to future change due to climate warming. The complexities brought about by diverse flood mixtures require process‐based approaches for understanding and modeling future flood frequency distributions.

New urban politics as post-politics of schooling marketization and distribution in entrepreneurial Chinese cities

ABSTRACT The inadequacy of urban scale in analyzing school system restructuring has generated criticism. Thus, this study interprets school system restructuring as a locally embodied process that produces variegated externalities for local people. This interpretation shifts the position of school system restructuring within the debate on new urban politics (NUP). Following the post-democratic understanding of NUP, we propose three research questions. Firstly, how does school system restructuring produce a new benefit structure that potentially causes dissent from the local society? Secondly, how do different social forces shape the restructuring? Thirdly, how can consensus on the restructuring be reached? We answer by using China as a case study. China has undergone a shift from a public school system to a mixed provision-regulation regime since the 1990s. The comparative analysis of two Chinese cities illustrates the differences in the school system restructuring embedded in local entrepreneurial strategy and the crucial role of the local state in facilitating the restructuring. In Chengdu, school system restructuring has resulted in dissent from middle class households that have the power to reshape the restructuring. In Mianyang, the school system restructuring disadvantaged the working class who was persuaded by the municipality’s discursive strategy to accept the restructuring.

Indoor culture scaling of Gracilaria chilensis (Florideophyceae, Rhodophyta): The effects of nutrients by means of different culture media

Gracilaria chilensis is distributed in New Zealand (including Chatham Island) and South America. This species has a three-stage sexual life cycle, as well as asexual and vegetative reproduction, and is commercially important as it is a valuable source for producing agar. However, basing the crops exclusively on clonal reproduction and vegetative propagation has led to a reduction in their genotypic diversity, an increase in their susceptibility to infection by epiphytes, and a decrease in their quality. Thus, it is important to establish indoor cultures of G. chilensis from thalli with a mixed reproductive regime (sexual and asexual) that maintains the genetic variability of the cultivars. In this study, the biomass, growth rate, and productivity of indoor cultures of G. chilensis were evaluated (as a first approach) using various culture media (i.e., von Stosch medium (VS), Basfoliar® Aktiv (BF), and mixtures of VS and BF, namely, VS/BF-A and VS/BF-B). The VS/BF-A medium showed the best results in terms of biomass (51.8 ± 3.7 g m–2), growth rate (4.55 ± 0.43 %d–1), and productivity (14 g m–2 d–1), including the occurrence of thalli with cystocarps. The positive results using the VS/BF-A medium could be attributed to the fact that BF provides different elements (K, Cu, Mo, and Zn) that are crucial, since they are involved in numerous physiological functions in the algae, and also to the N:P ratio utilized (1:1), which positively affects growth and productivity. This information provides pivotal updated knowledge regarding cultures of G. chilensis under controlled conditions, promoting its successful cultivation for productive purposes.

Study the mixed valence problem in asymmetric Anderson model: Fano–Kondo resonance around Fermi level

We numerically calculate the local density of states (LDOS) in asymmetric Anderson model in mixed valence regime using hierarchical equations of motion approach. Based on the idea that the asymmetric line shape of LDOS around Fermi level stems from the interference between the single particle resonance and the Kondo resonance, we perform a fitting. From the fitting results, we obtain the Kondo temperatures and the Fano factors with changing the single particle energy. The tendency of Kondo temperature agrees with the previous analytic expressions and the Fano factors are in an expected variation of Fano resonance. Our study shows that the Fano–Kondo resonance can reasonably explain the asymmetric line shape of the LDOS around the Fermi level.

Synergetic Effects of Mixed-Metal Polyoxometalates@Carbon-Based Composites as Electrocatalysts for the Oxygen Reduction and the Oxygen Evolution Reactions

The smart choice of polyoxometalates (POMs) and the design of POM@carbon-based composites are promising tools for producing active electrocatalysts for both the oxygen reduction (ORR) and the oxygen evolution reactions (OER). Hence, herein, we report the preparation, characterization and application of three composites based on doped, multi-walled carbon nanotubes (MWCNT_N6) and three different POMs (Na12[(FeOH2)2Fe2(As2W15O56)2]·54H2O, Na12[(NiOH2)2Ni2(As2W15O56)2]·54H2O and Na14[(FeOH2)2Ni2(As2W15O56)2]·55H2O) as ORR and OER electrocatalysts in alkaline medium (pH = 13). Overall, the three POM@MWCNT_N6 composites showed good ORR performance with onset potentials between 0.80 and 0.81 V vs. RHE and diffusion-limiting current densities ranging from −3.19 to −3.66 mA cm−2. Fe4@MWCNT_N6 and Fe2Ni2@MWCNT_N6 also showed good stability after 12 h (84% and 80% of initial current). The number of electrons transferred per O2 molecule was close to three, suggesting a mixed regime. Moreover, the Fe2Ni2@MWCNT_N6 presented remarkable OER performance with an overpotential of 0.36 V vs. RHE (for j = 10 mA cm−2), a jmax close to 135 mA cm−2 and fast kinetics with a Tafel slope of 45 mV dec−1. More importantly, this electrocatalyst outperformed not only most POM@carbon-based composites reported so far but also the state-of-the-art RuO2 electrocatalyst. Thus, this work represents a step forward towards bifunctional electrocatalysts using less expensive materials.

Formulation of lyotropic liquid crystal emulsion based on natural sucrose ester and its tribological behavior as novel lubricant

The tribological behavior of oil-in-water emulsions formulated with natural lyotropic liquid crystal (LLC) emulsifiers based on natural sucrose ester was studied for the first time. Polarized optical microscopy, synchrotron radiation small-angle X-ray scattering, wide-angle X-ray scattering, and synchrotron radiation infrared microspectroscopy demonstrated that LLC emulsifiers were tightly ordered at the oil—water interface with a distinct nematic texture. The viscosity of emulsion was observed to change over time. Moreover, the zeta potential and laser particle size distribution verified the emulsion’s satisfactory stability. The frictional shearing test proved that the coefficient of friction of the emulsion versus pure oil decreased by 34.2%. The coefficient of friction of the emulsion with liquid crystal decreased 10.1% versus that without liquid crystal. Although liquid crystal emulsion did not exhibit outstanding anti-wear performance compared with pure oil, its wear volume was 29.4% less than the emulsion without liquid crystal. X-ray photoelectron spectroscopy and scanning electron microscope—energy dispersive X-ray spectroscopy (SEM—EDS) proved that the tribo-film of the emulsion with liquid crystal was formed synergistically by the liquid crystal phase with the base oil. The formulation affecting the lubricant quality was further studied by orthogonal experiments. The resulting Stribeck curve behavior suggested that proper composition with a slightly higher viscosity can better reduce friction in both boundary lubrication and mixed lubrication regimes. The lubrication mechanism indicated that the periodically ordered liquid crystal was transported to the sliding asperity in the form of emulsion droplets, which bored the pressure and released the oil to form a tribo-film. This LLC emulsion is environmentally friendly and potentially non-irritant to the skin. Thus, it has promising application prospects as novel water-based and biological lubricants.

Numerical simulation of a low Prandtl number flow over a backward facing step with an anisotropic four-equation turbulence model

In recent years the use of liquid metals has become more and more popular for heat transfer applications in many fields ranging from IV generation fast nuclear reactors to solar power plants. Due to their low Prandtl number values, the similarity between dynamical and thermal fields cannot be assumed and sophisticated heat turbulence models are required to take into account the anisotropy of the turbulent heat transfer involving liquid metals. In the present work, we solve an anisotropic four-equation turbulence model coupled with the Reynolds Averaged Navier Stokes system of equations to simulate a turbulent flow of liquid sodium over a vertical backward-facing step. We implement an explicit algebraic model for Reynolds stress tensor and turbulent heat flux that takes into account flow anisotropic behavior. We study forced and mixed convection regimes when a uniform heat flux is applied on the wall behind the step. Linear isotropic approximations for eddy viscosity and eddy thermal diffusivity underestimate the turbulent heat flux components while this anisotropic model shows a better agreement with DNS results.

Dynamic adjustment of the Eddy Dissipation Concept model for turbulent/combustion interactions in mixed combustion regimes

The Eddy Dissipation Concept (EDC) combustion model, in comparison with some other combustion models, has drawn attention, especially for the Moderate or Intense low oxygen Dilution (MILD) combustion. The original formulation of the EDC combustion model is not developed for the MILD combustion regime, and a revision of the model could be considered. In this study, the effect of the characteristic frequency on the EDC combustion model has been investigated, and some parametric studies on the ratios of length and time scales of the fine structures to the Kolmogorov scales have been performed. Results revealed that finding optimum model constants for all combustion field with a wide range of Damköhler numbers seems to be complicated. The variations in scales ratio of fine structure to the Kolmogorov eddies shows different consequence at low and high Damköhler number combustion regions which leads to a conclusion on difficulties for EDC model global optimization. As a solution, a localized modulation method based on some local variables such as the turbulence Reynolds number and Damköhler number has been developed and applied on the Adelaide Jet in Hot Coflow(JHC) and Delft Jet in Hot Coflow (DJHC), and in addition in supplementary material on Sandia/TUD piloted flame and Sydney bluff-body burners. These burners demonstrate combustion regimes with both low and high Damköhler numbers. Results have shown the better performance of the local approach in the simulation of the burners. The improvement is more perceptible at the sections far from the inlet, where Damköhler number is increased, in comparison with the standard (default) EDC model. The average of deviations from the measurements is decreased by more than 10% and even more by a decrement in oxidizer oxygen level.

Pedestal analysis of MAST ELMy regimes

Mega Ampere Spherical Tokamak (MAST) pedestal data has been analysed, where a pedestal database of 892 shots was obtained, using the upgraded MAST Thomson scattering (TS) diagnostic. Various edge localised mode (ELM) types are discussed, where characteristics and trends of MAST pedestals are shown. The data from the upgraded TS diagnostic confirms pedestal characteristics found in earlier analysis, using previous TS systems. Using the database, calculations of the bootstrap current are obtained using the different analytical formulae (Sauter and Redl), and comparisons are performed. The upgraded MAST TS system now spans the full plasma mid-plane, such that direct comparisons between inboard and outboard pedestals can be obtained, and asymmetries in the density pedestal width were found. To increase confidence in spherical tokamak pedestal predictions, the assumptions of Europed have been validated from the MAST pedestal data, and a value for the kinetic ballooning mode constraint () has been obtained. The first spherical tokamak pedestal predictions were performed in Europed and compared to experimental values. Using C = 0.145 the temperature pedestal height was predicted to within 10% of the experimental value. In addition type II ELMs on MAST are analysed, and stability analysis and parameter scans have been performed using ESSIVE. Similar magneto-hydrodynamic (MHD) stability properties are observed for type I and type II ELMs, originating from the mixed ELM regimes; it is therefore difficult to distinguish these ELMs using the ideal MHD codes.

Effect of particle concentration on lubrication performance of cellulose nanocrystalline (CNC) water-based lubricants: mixed lubrication regime

Effect of particle concentration on lubrication performance of cellulose nanocrystalline (CNC) water-based lubricants: mixed lubrication regime

Improving tribological properties and shear stability of base lubricant using Eichhornia crassipes carboxylmethyl cellulose polymer under different conditions

In response to the global environmental issues over inorganic additives in lubrication process in solving friction and wear challenges. There is growing interest in the development of polymer additives, particularly bio-polymer, to address the issues given by friction and wear of contact surfaces exposed to boundary and mixed lubrication regimes. The investigation employed a unidirectional ball on disc tribo-tester machine. Using rapeseed lubricant as a base oil sample, this study examined the effect of bio-based Eichhornia crassipes carboxylmethyl cellulose (EC-CMC) polymer to inorganic polyphosphate as well as mixing the two to determine their synergetic and antagonistic effect on reducing friction and wear. The additives were tested for tribological enhancement in terms of friction and wear reduction, and load-carrying effect. Scanning Electron Microscope (SEM) and energy dispersive x-ray (EDX) spectroscopy were used to examine the substrate morphology and elemental distribution of worn surfaces. Introducing 1 wt% EC-CMC, 1 wt% polyphosphate, and 1 wt% EC-CMC + 1 wt% polyphosphate into the base lubricant resulted in improved lubricant performance and reduced friction and wear. However, as compared to base rapeseed oil, the polyphosphate sample provided the best friction (44.8%), while EC-CMC gives better wear reduction (0.3073). The higher the operating capacity, the better the tribological properties of nanoparticles, according to the findings. The best tribofilm creation performance, notably with EC-CMC, is achieved when a load of 100 N is applied, resulted in outstanding tribological performance. When compared to polyphosphate, the strong and efficient nature of EC-CMC results in excellent shear stability.

Rolling Bearing Condition Monitoring Technique Based on Cage Rotation Analysis and Acoustic Emission

The objective of this paper is to present an approach for the detection of change in rolling element bearings (REB) operating conditions that can lead to premature failure. The developed technique is based on the measurement of the kinematics of the bearing cage. The rotational motion of the cage is driven by the traction forces produced in the contacts of the rolling elements with the races. It is known that the cage angular frequency relative to shaft angular frequency is dependent of the bearing load, the bearing speed and the lubrication condition, as these factors are determinant for the lubricant film thickness and the associated traction forces. As an important part of REB failures are caused by misalignment or lubrication problems, any evidence of these conditions should be interpreted as an incipient fault. In this paper a novel method for the determination of the instantaneous angular speed (IAS) of the cage is developed. The method is evaluated in a deep grove ball bearing test rig equipped with the cage IAS sensor, as well as custom acoustic emission (AE) transducer and a piezoelectric accelerometer. The cage IAS is analyzed under different bearing loads and shaft speed, showing the dependence of the cage angular speed with the calculated lubricant film thickness. Typical bearing faulty operating conditions (mixed lubrication regime, lubricant depletion and misalignment) are recreated and it is shown that the cage IAS is dependent on the lubrication regime and is sensitive to misalignment. The AE signal is used as a lubrication regime evaluator as well. Experimental results show that the proposed technique can be used as a condition monitoring tool to detect abnormal REB conditions that can lead to premature failure.

Torsion Wear Behavior of PEEK-on-UHMWPE as an All-Polymer Joint Combination in Total Knee Replacement

Polyether ether ketone (PEEK) has been considered as an alternative material to cobalt chrome in the femoral component of a total knee replacement. In this article, the experimental simulation of torsion wear for a PEEK and CoCr femoral head against an ultra-high-molecular-weight polyethylene (UHMWPE) tibial pad was carried out using a two-station knee simulator. The testing results showed that T-θ curves of torsion wear for PEEK-on-UHMWPE bearing couples showed three types of morphological characteristics, such as linear, elliptical, and parallelogram shapes. With an increase in torsion angular displacement, T-θ curves changed from the linear to the parallelogram type, and the relative motion state changed from the partial slip regime coordinated by the elastic deformation to the slip regime with plastic deformation. With an increase in normal load, the T-θ curve changed from the parallelogram to the elliptical type, and the relative motion state changed from the slip regime to the mixed slip regime. Under intermediate torsion wear conditions, the wear factors of UHMWPE were 11.25 ± 2.08 × 10−6 mm3/C and 14.65 ± 2.49 × 10−6 mm3/C against PEEK and CoCr. Under high torsion wear conditions, the wear factors were 20.51 ± 3.23 × 10−6 mm3/C and 23.26 ± 3.01 × 10−6 mm3/C, respectively. The wear surface of UHMWPE against PEEK showed slight adhesive wear and plastic deformation in the center, and abrasive wear with local fatigue spalling was found at the edges. The wear topographies presented characteristics similar to the CoCr bearing combination.

An experimental investigation of the potential of empirical correlations derived based on Dalton’s law and similarity theory to predict evaporation rate from still water surface

This paper investigates the applicability of two approaches (similarity theory and Dalton’s law) in predicting the evaporation rate. The results of this study showed that conventional Dalton’s based models could not be used to predict the evaporation rate at all convection regimes. Thus, a new formula as a function of vapor density difference was developed to predict evaporation rate at natural turbulent convection. However, still, it cannot get an acceptable result. Also, another two formulas were developed to predict the evaporation rate at forced and mixed convection regimes after considering the nonlinear relationship between the evaporation rate and the vapor pressure difference. The evaporation rate is proportional to the exponent ( n) of the partial vapor pressure difference. This exponent was written as a function of the higher-order polynomial of air velocity to get a good match between experimental results and predicted value, and satisfactory results were achieved. Similarity theory is an analogy between heat and mass transfer methods used to predict the evaporation rate from the still free water surface. The results show that the evaporation rate obtained from the similarity method is much larger than the actual evaporation rate. The similarity theory considers the effect of the vapor density difference. Thus, it can be observed that the experimental results and similarity method results are in good agreement at natural turbulent convection. It is noteworthy that the similarity theory cannot predict the evaporation rate from the still water surface at forced convection. In this convection regime, the evaporated water surface is not completely smooth, which violates the assumption of the similarity theory. A nonlinear regression analysis was conducted to evaluate the empirical correlation of the Sherwood number for mixed convection under turbulent conditions with the exponent n as a logarithmic function of the ratio [Formula: see text], then derived a new formula that can be used to evaluate evaporation rate at mixed convection regime, and the results are in good agreement with the experimental results. The laboratory measurements are made using the large wave tank-wind tunnel combination to control wind speed.

The Effect of Populism on American and Turkish Judiciaries

In this article, I study the relationship of populism and judicial independence. I argue that populism poses a threat against the latter. Specifically, I use Turkey and the United States as illustrative case studies. First, I explain what an independent judiciary looks like, and proceed to explain the importance of a judiciary in a democracy, defined as a mixed regime. Furthermore, I discuss the threats facing judiciaries in the face of rising populist movements in Turkey and the United States. In Turkey, judges seen as disloyal to President Erdogan are replaced with judges that will rule in favor of the administration. In the United States, up to 90% of judges are elected, which is problematic for reasons related to the election mechanism’s relationship with democracy. Furthermore, there is a history of pressuring the judicial branch to conform to the wishes of the executive branch in America, which will also be examined. Finally, I will relate these pressure tactics to the idea of judicial populism. This notion, which states that courts may alter their opinions to appease a populist executive, has had wide-ranging policy implications. I will examine some of these in the paper.