Conversion Phenomena Research Articles

Land Conversion in Namlea District

The phenomenon of agricultural land conversion in Namlea subdistrict becomes a problem when the number of productive land is increasingly reduced and affects land availability for agricultural production. Research was conducted to describe the conversion of agricultural land and its utilization in Namlea subdistrict. The research site focuses on Namlea District Buru Regency with consideration of the availability of the number of agricultural land that is less than other districts in Buru Regency. The number of informant interviewed as many as 40 people consisting of land owners, farmers, business owners and village apparatus. Analytical techniques used to follow the concept of Miles and Huberman where activities in the analysis of qualitative data are conducted interactively and continuously to find saturation in data processing. The results showed that the reduction of farmland in Namlea district was due to the conversion of land for various activities including housing and development of the Trade Center. In addition, the use of converted land is caused by the system of personal ownership that is secured by the Government through the right to building or proprietary rights but has not fully set the long-term oriented land utilization pattern.

Sejarah Pembinaan terhadap Suku Anak Dalam di Kabupaten Batanghari Provinsi Jambi (1970-2014)

The focus of the problem in this study is to analyze the coaching process carried out by the Government and NGOs. The phenomenon of forest conversion into large oil palm plantations has eliminated the source of livelihoods of the SAD community, which largely depends on forest products. Transfer of land functions also caused some SAD out of their original home range and made SAD fragmented and formed groups with new identities. The study was conducted using historical research methods with a socio-cultural approach. The use of development theory is needed to support the writing of this thesis. From the results of the study it was found that the impact of the formation and effect of the conversion of forest functions which were used as large oil palm plantations and settlements of transmigrants during the New Order changed some SAD communities to shift their livelihoods, change their mindset, broaden their traditions and culture of origin and shape their origin a new identity. After entering the period of Regional Autonomy, the SAD people who were initially silent and accepted all the policies that came from the Central Government, now become a tough person and oppose all the injustices that were perpetrated by the New Order Government. SAD began to demand customary rights in the form of customary land which affected the next Government.

Thermal-hydraulic analysis of the thermoelectric space reactor power system with a potassium heat pipe radiator

The thermoelectric space reactor power system conceptual design incorporates fast reactor, liquid-lithium primary coolant loops that transfer heat to potassium-filled high temperature heat pipes and thermoelectric generators. An integrated system analysis model was developed to study the operating characteristics of the space power system, which consisted of reactor thermal-hydraulic model, neutron kinetics model, thermoelectric energy conversion assembly (ECA) model, heat pipe radiator model etc. One-dimensional thermal-hydraulic model was applied to model the coolant circuit. Quasi two-dimensional analysis models for heat transfer of fuel element, ECA and the heat pipe fin were established. Considering the thermoelectric conversion phenomena, an equivalent electric efficiency model was inserted in the ECA model. Both finite element method and thermal resistance network were applied to simulate the potassium heat pipe system. The normal operation condition and two demonstration accident scenarios (unprotected inadvertent movement of a sliding reflector and loss of heat pipes) were calculated to prove the capabilities of the new system model.

Aiming high: social and academic correlates of applying to and attending ‘reach’ universities

Less privileged students disproportionately aim low with their university applications and often fail to apply to the institutions that match their academic qualifications. Little attention, however, has been directed toward the converse phenomenon, that of aiming high. These kinds of applications are commonly called ‘reaches,’ meaning an applicant’s credentials fall slightly below the institution’s range for the average first-year student. Using nationally representative survey data from the United States, this study examines whether social background predicts the likelihood of applying to reach institutions and assesses the consequences for disparities in enrollments. We find a strong relationship between students’ socioeconomic background and their likelihood of applying to reach institutions, even after controlling for a range of academic and non-academic characteristics. Further, there is a substantial pay-off to applying to reach institutions, revealing the degree to which these class-based choices at the application stage contribute to the social stratification of higher education.

Atheism by Alexandre Kojève

Reviewed by: Atheism by Alexandre Kojève James H. Nichols Jr. KOJÈVE, Alexandre. Atheism. Translated by Jeff Love. New York: Columbia University Press, 2018. xxxix + 203 pp. Cloth, $32.00 A few years before beginning his famous course on Hegel's Phenomenology of Spirit, Alexandre Kojève wrote, in Russian, a manuscript entitled Atheism. Found among his papers at the Bibliothèque nationale, the manuscript was translated into French by Nina Ivanoff, edited by Laurent Bibard, and published by Gallimard in 1998. Jeff Love has now presented us with an English translation from the original Russian text, along with a thoughtful introduction that situates Kojève's essay in relation to theological themes prominent in Russian thought, to such powerful thinkers of the day as Husserl and above all Heidegger, and to earlier and later expressions of Kojève's own philosophical development. Kojève begins his inquiry from the notion of Buddhism as an atheistic religion, and near the end of the essay he endorses that formulation. One tends to think of religion as necessarily conjoined with theism, and secularism with atheism, but in Kojève's view this is inadequate: Buddhism is an atheistic religion, and Aristotle's philosophy is a theistic secularism. Kojève's inquiry seeks to clarify and to give a deeper sense of what is it to be an atheist and what it is to be a theist. He sets forth from the evident assertion that for the atheist, there is nothing outside the world that is given to us, whereas for the theist living in the world, outside of the world there exists something other: some divine being or beings, God. But as Kojève mulls over the matter further, it becomes more complicated. From the point of view of pure or unqualified theism (that is, an acceptance of God combined with the conviction that one cannot reasonably ascribe any qualities to God), God is viewed as altogether other than things of this world; God is not a thing. Could it be that God is therefore nothing, in which case the difference between the theist and the atheist would seem to disappear? Further reflection on this problem leads to thinking about how anything outside the world could be given to one living in the world, how one can grasp the difference between being and nonbeing, and how one may speak coherently about finitude and infinity. In the course of this thinking, the central importance of death emerges. Foreseeing one's own death may be the chief way in which being outside the world is given to one living in the world. The atheist believes that his existence ends with his death in the world, outside of which there is nothing and he is nothing; his soul is mortal. The theist tends to believe that his soul survives death, moves outside the world, and is in interaction with God. Given Kojève's well-known adoption of an atheistic Hegelianism soon after writing this essay, the genuine seriousness with which he takes both the theist and the atheist positions—or rather their fundamentally different intuitions—is noteworthy. We are filled with uncertainties about death, as the border between this world and another or between being and nothingness. Both theistic and atheistic intuitions of human being in the world are genuine and powerful, and we may well move between one and another. "Who has not wavered?" Kojève asks at least twice. He refers too to the well-known phenomenon of death-bed conversion. He suggests that [End Page 142] one may know definitively what one is, atheist or theist, only at the moment of one's death. In a footnote near the end of this book, Kojève states, "What I am writing here, strictly speaking, is only a sketch of my philosophy and thus it is also not final nor can it be published." The clearest evidence of the unfinished character of Kojève's essay is to be found in the footnotes, where he often exhorts himself to think further about a question, or even to ask Koyré about it; he indicates toward the end that this essay would be the...

A study on guided wave propagation in a long distance curved pipe

Guided ultrasound is effective for inspecting long-range structures and inaccessible areas. Large structures such as long-distance piping contain curved tubes, and it is difficult to establish the reliability of a test depending on the excretion environment and the scope of the test. When an ultrasonic wave propagates in the circumferential direction like in a curved pipe, the existing torsional wave is converted into a circumferential wave from the curved pipe, and then, the torsional mode occurs again after the curved pipe. In this paper, we defined the factors affecting the wave propagation in a curved pipe welded to a cylindrical pipe. Experimentally, the mode conversion phenomenon that occurred in the curved pipe was confirmed, and this technique can have an important role in quantitative signal analysis of buried pipes and the inspection of inaccessible pipes.

(Invited) Tuning of Catalytic Activity By Thermoelectric Effect

Thermoelectric (TE) materials convert temperature difference directly into electrical voltage via the Seebeck effect, S= -V/ΔT where V is the voltage between the two ends of the TE material and ΔT the temperature difference, S is the Seebeck coefficient. It has been used for energy harvesting from waste heat, and for silent cooling via its converse phenomenon the Peltier effect. Here we report its novel application as a catalyst promoter. Catalyst promoters can generally be divided into structural and electronic promoters. Structural promoters enhance and stabilize the dispersion of the catalyst on the support. Electronic promoters induce changes of electronic state of the catalyst near the Fermi level. These promoters are added or fixed during the catalyst preparation, therefore can subject to degradation during catalytic process. We report here the realization of in situ, controllable, reversible, and significant modification of catalytic activity, through the generation of a Seebeck voltage. A chamber reactor which combine TE effect with catalytic chemical reaction was assembled.1, 2 The chamber was placed directly on a hot-plate, and its top cap was water cooled. A disc TE BiCuSeO (BCSO) sample of 20 mm in diameter and about 2 mm in thickness was then placed into a specific glass ceramic holder and attached to the cold surface of the cap for catalytic reaction investigation under the usual TE conditions. As the back side of the disc was in contact with the water cooled stainless steel cap, its temperature was never higher than 373 K, so a large temperature gradient therefore a large Seebeck voltage across the sample thickness was created when the front surface of the disc reached a high temperature Th. Under the reduced TE (RTE) condition, the back surface of the disc was not in contact with the cap, therefore the temperature gradient across the disc thickness and also the Seebeck voltage were much smaller. Figure 1a shows the ethylene oxidation reaction rates at different front surface temperatures Th for a sample of Pt thin film of 80 nm supported on BCSO with a large TE effect (red marks, Pt(80)/BCSO TE), and under a reduced TE effect (blue marks, Pt(80)/BCSO RTE) conditions respectively. For comparison purpose, the ethylene reaction rate on a typical catalyst for this reaction Pt thin film on Y2O3-stabilized ZrO2 (YSZ, green marks, Pt(80)/YSZ) is also depicted in Fig. 1a. For Pt(80)/BCSO TE, when the front surface Th was at 666 K, the backside temperature Tc was 349 K, so a temperature difference of 317 K existed across the BCSO thickness, which generated a Seebeck voltage -71 mV. For the same sample under the reduced TE effect (Pt(80)/BCSO RTE), at 553 K, the measured Seebeck voltage was -3.1 mV, and the reaction rate was much lower than that for Pt(80)/YSZ at a similar temperature 563 K. This was probably because the surface area of the Pt(80)/BCSO was much smaller than for Pt(80)/YSZ. However, with the increasing temperature, the reaction rates for Pt(80)/BCSO under TE and RTE conditions increased much faster than for non-TE YSZ supported catalyst. Further detailed investigation demonstrated that when the total reaction rate was lower than a certain value, a linear relationship existed between the logarithm of the reaction rate and the Seebeck voltage.1, 2 We called this thermoelectric promotion of catalysis (TEPOC). To confirm the above observed TEPOC can also be observed in other reactions, the same samples were used as catalysts for carbon dioxide hydrogenation. The inlet gases were CO2 and H2, and the reaction products observed were CO and CH4, with the vast majority (>90%) being CO. Similar as was observed for ethylene oxidation, for the same sample under the same inlet gas composition, the CO2 conversion rates r under TE conditions were much higher (between 10 to 30 times) than under RTE conditions. Again, a good linear relationship between Ln(r) and -eV/kbTh was observed (Figure 1b). The effects of the Seebeck voltage on the catalytic activity under different reaction conditions, such as fuel-lean and fuel-rich conditions for the ethylene oxidation, have also been investigated. The underlying mechanisms based on metal-semiconductor contact theory and work function change, as well as the comparison with the Electrochemical Promotion of Catalysis, will be discussed.

Topic Maintenance and Topic Transition in a Couple’s Dinnertime Conversation

This paper investigates the patterns of topic maintenance and topic transition used to create conversation and their accompanying structural features speakers employ to signal these two conversational phenomena. The data are a 21-minute dyadic dinnertime conversation between a boyfriend and girlfriend; they are both native speakers of American English, in their late twenties. The two significant findings of the study are as follows. First, the data reveal that the speakers used three major techniques, namely minimal responses, substitutions, and deletions, to maintain the same topic of the conversation (Goffman, 1983; Radford & Tarplee, 2000; Abu Akel, 2002; Sukrutrit, 2010; Jeon, 2012). Second, in the analysis of topic transition, the data show that the speakers resorted to different types of topic transitions (i.e., collaborative, unilateral, linked, minimally linked, and sudden) to end an ongoing topic and start a new one (West & Garcia, 1988; Ainsworth-Vaughn, 1992; Okamoto & Smith-Lovin, 2001; Sukrutrit, 2010; Jeon, 2012).

Soliton supermode transitions and total red shift suppression in multi-core fibers.

Soliton propagation in seven-core fibers is studied numerically with the frequency dependence of linear coupling taken into account. It is shown that under certain conditions, solitons can undergo spontaneous supermode transitions upon abrupt red shift, analogous to the recently discovered phenomenon of soliton self-mode conversion in step-index multi-mode fibers. When the core separation is increased, the dynamics change drastically, leading to total suppression of soliton self-frequency shift and the emergence of spatially oscillating solitonic structures with resemblance to solitons in graded-index multi-mode fibers. The observed phenomena are general multi-core effects and not specific to seven-core fibers.

Simultaneous Conversion Conditions of Ammonia and Sulfate in ANAMMOX Systems

A continuous flow stirred tank reactor (CFSTR) was used to inoculate mixed sludge (with an ANAMMOX sludge to sewage concentrate sludge ratio of 1:1) to study the simultaneous conversion of NH4+ and SO42-. The ORP value in the system was stabilized at (-200±50)mV by continuously adding sludge. The simultaneous conversion lasted for 42 days. The average conversion of NH4+-N was 14.81 mg·L-1 while that of sulfate-sulfur was 8.77 mg·L-1. In the batch experiment, the anaerobic conditions were influenced by whether the solution was filled with glass bottles. Both NH4+ and SO42- in the non-filled group were reduced, but their transformation was not simultaneous. In the fully filled group, NH4+ was not transformed, the concentration of SO42- decreased significantly, and S2- was detected in the later stages of the experiment. It is indicated that the general conditions for the phenomenon of simultaneous conversion are:①sufficient NH4+ and SO42-, ② inoculating mixed sludge with appropriate concentration, ③ leaking oxygen, ④ the detection value of ORP within the range of -150 to -300 mV. At the same time, the experimental conditions used in this paper and in other related literature cannot prove that the simultaneous conversion of NH4+ and SO42- is the result of mutual transformation; on the contrary, observations are more conducive to the independent transformation of NH4+ and SO42-.

The phenomenon of conversion of the donor-derived blood group to the patient’s original blood group after ABO-incompatible hematopoietic stem cell transplantation in a patient with Wiskott–Aldrich syndrome

We present a clinical case of hematopoietic stem cell transplantation (HSCT) in a patient with Wiskott-Aldrich syndrome. In spite of donor different ABO-system, the own blood group was verified in 6 months after HSCT, which was initially regarded as a risk of myeloid rejection. During the diagnosis, the hypothesis of absorption of the recipient’s ABO-system proteins onto the donorderived red blood cells was confirmed. The study of the immunological profile allowed to exclude the risks of hemolytic reactions and to predict a favorable outcome in the patient. Parents gave their consent to use information about the child in the article.

Elastic wave mode conversion phenomenon in glass fiber-reinforced polymers

PurposeThe purpose of this paper is to present the results of experimental analysis of the elastic-guided wave mode conversion phenomenon in glass fiber-reinforced polymers. The results of this research presented in this paper are strictly focused on S0/A0’ mode conversion phenomenon caused by discontinuities in the form of circular Teflon inserts (artificial delaminations) and impact damage. Results of this research could be useful in problems of damage detection and localization.Design/methodology/approachIn the research, guided waves are excited using a piezoelectric transducer and sensed in a non-contact manner using a scanning laser Doppler vibrometer. Full wavefield measurements are analyzed. Analysis of the influence of investigated discontinuities on S0/A0’ mode conversion is based on the elastic wave mode filtration in frequency-wavenumber domain. Mode filtration process allows us to remove the effects of the propagation of unwanted type of mode in forward or backward direction. Effects of S0/A0’ mode conversion are characterized by a mode conversion indicator (MCI) based on the amplitude of new mode A0’ and the amplitude of incident S0 mode.FindingsIt was noticed that the magnitude of MCI depends on the depth at which the Teflon inserts were located for all analyzed excitation frequencies and diameters of inserts (10 and 20 mm). The magnitude of MCI also increases with increasing impact energies. The S0/A0’ mode conversion phenomenon could be utilized for the detection of surface and internal located discontinuities.Originality/valueThis paper presents the original results of this research related to the influence of discontinuity location with respect to the sample thickness and severity of discontinuity on S0/A0’ mode conversion.

Linear Dichroism Conversion in Quasi-1D Perovskite Chalcogenide.

Anisotropic photonic materials with linear dichroism are crucial components in many sensing, imaging, and communication applications. Such materials play an important role as polarizers, filters, and waveplates in photonic devices and circuits. Conventional crystalline materials with optical anisotropy typically show unidirectional linear dichroism over a broad wavelength range. The linear dichroism conversion phenomenon has not been observed in crystalline materials. The investigation of the unique linear dichroism conversion phenomenon in quasi-1D hexagonal perovskite chalcogenide BaTiS3 is reported. This material shows a record level of optical anisotropy within the visible wavelength range. In contrast to conventional anisotropic optical materials, the linear dichroism polarity in BaTiS3 makes an orthogonal change at an optical wavelength corresponding to the photon energy of 1.78 eV. First-principles calculations reveal that this anomalous linear dichroism conversion behavior originates from the different selection rules of the parallel energy bands in the BaTiS3 material. Wavelength-dependent polarized Raman spectroscopy further confirms this phenomenon. Such a material, with linear dichroism conversion properties, could facilitate the sensing and control of the energy and polarization of light, and lead to novel photonic devices such as polarization-wavelength selective detectors and lasers for multispectral imaging, sensing, and optical communication applications.

Low-profile reflective polarization conversion metasurface with frequency selective characteristics

We proposed a low-profile reflective polarization converter based on anisotropic metasurfaces. By properly designing the unit cell structure, the proposed metasurface can achieve frequency selective polarization conversion. When the proposed metasurface is illuminated by a linear polarization incoming wave, the circular polarization outgoing waves are implemented in frequency-band-1 (6.87 to 16.83 GHz) and frequency-band-2 (19.72 to 23.64 GHz), but the rotation direction of the circularly polarized reflections are orthogonal over the two bands. In addition, cross polarization conversion is achieved in frequency-band-3 (17.38 to 18.6 GHz). Indeed, the proposed metasurface can also serve as a circular to linear polarization converter. The theoretical analysis and the physical mechanism are given to understand the polarization conversion phenomenon. The measured result is consistent with the simulation. The proposed metasurface can be utilized in the design of a circularly polarized reflectarray with linearly polarized feeding.

Sliding Wear and Freeplay Growth due to Control Surface Limit Cycle Oscillations

Freeplay in flight control surface linkages leads to nonlinear aeroelastic behavior including limit cycle oscillations (LCO). LCO due to a constant freeplay has been extensively studied, whereas the converse phenomenon of mechanical wear and freeplay growth due to LCO is little explored. In the present work, a first-of-its-kind theoretical model for freeplay growth is developed by introducing LCO characteristics into Archard’s sliding wear model. The closed-form solution for a fixed airspeed is validated against an iterative method in prior literature and subsequently extended to the case of time-varying flight conditions. It is observed that under the action of LCO the freeplay will grow to become unbounded in finite time. The influence of the geometry and material properties of the bearings and links on freeplay growth is discussed, which can aid in actuation circuit design. The utility of the model is demonstrated by calculation of freeplay growth trends due to LCO and also by analysis of freeplay limits from the design/maintenance perspective.

A mathematical model of the Lamb wave reflection at a two-dimensional rectangular notch

Due to the long-range propagation ability of the Lamb wave, defect locations can be effectively detected. However, the evaluations of the defects are not yet quantitative because of the unsolved complex relation between the defect morphology and the signal detected. In this paper, to reveal the reflection phenomena of the Lamb wave, a simple mathematical model was proposed and evaluated. In the reflection of the Lamb wave at a defect in a plate, mode conversions among the specific propagation modes of the Lamb wave occur. The mathematical model proposed here took the mode conversion phenomena into consideration. It was confirmed that the mathematical model agreed very well with the experimental results. In order to improve the mathematical model, an interesting assumption of the regrowth process from scattered bulk waves to the Lamb wave initiated just after a discontinuity was also discussed as a modified model.

Farmers Household Strategy in Land Conversion Dynamics (Case Study of Penrang District, Wajo Regency, South Sulawesi)

The exploding demand for palm oil in the world market makes oil palm expansion in several tropical countries increasingly increasing, especially in Indonesia. The phenomenon of land conversion that occurred in Wajo Regency was caused by the entry of plantation companies which resulted in the shifting of livelihood systems and livelihood strategies. Changing agricultural land into an oil palm plantation area with a partnership system has an impact on the limited community in managing and accessing their land. Farming activities for both rice and other commodities such as cashew and others as well as cattle grazing activities cannot be done on agricultural lands that have been partnered for oil palm plantations. This condition triggered shocks to the farmer's household livelihood system. So that in the process the community carries out various adaptation of livelihood strategies. Therefore, this study aims to analyze the livelihood strategy of the community in meeting household needs before and after the conversion of agricultural land to oil palm plantations. This study uses snowball sampling and in-depth interviews conducted in the village of Taddangpalie, Penrang District. The results showed that the livelihood strategies of farmer households before conversion which had the largest percentage were survival strategies (53%), consolidation (30%), accumulative (17%) with the agricultural basis. After land conversion occurs there is a decrease in the survival strategy phase which is to be (48%) because some households switch the consolidation phase by (40%), and the accumulative phase still remains at the percentage, with the dominant basis being agriculture and non-agriculture. Vulnerability in the form of shock, trend, and equality is overcome by two types of strategies namely survival strategies and consolidation strategies by adopting human capital, social capital, natural capital, and financial capital.

Effective dynamic properties of random complex media with spherical particles.

The effective dynamic bulk modulus and density are presented for random media consisting of particles in a viscous host fluid, using a core-shell, self-consistent effective medium model, under the large compressional wavelength assumption. These properties are relevant to acoustic or dynamic processes in nano- and micro-particle fluids including particle density determination, resonant acoustic mixing, and acoustic characterisation. Analytical expressions are obtained for the effective bulk modulus and mass density, incorporating the viscous nature of the fluid host into the core-shell model through wave mode conversion phenomena. The effective density is derived in terms of particle concentration, particle and host densities, particle size, and the acoustic and shear wavenumbers of the liquid host. The analytical expressions obtained agree with prior known results in the limit of both static and inviscid cases; the ratio of the effective bulk modulus to that of the fluid is found to be quasi-static. Numerical calculations demonstrate the dependence of the effective mass density on frequency, particle size (from nano- to micro-regime), and concentration. Herein it is demonstrated both theoretically and numerically that the viscosity, often neglected in the literature, indeed plays a significant role in the effective properties of nanofluids.

Generation of long-range, near-cut-on guided resonances in composite panels

In this paper, near-cut-on guided resonances (GRs) are generated in a composite structure using an array of piezoelectric transducers. A GR is a type of high-order unidirectional wave mode, guided between the finite boundaries of a periodic waveguide’s cross section. Near their cut-on frequency, these waves often exhibit high chromatic dispersion and spatial decay, which compromise their potential use for wave-based inspection and structural health monitoring of advanced composites or metamaterials. A custom GR actuator is designed to achieve an accurate shape appropriation of the predicted 3D Floquet-Bloch solutions in a 3-m-long sandwich structure. An original wave conversion phenomenon is then exploited to generate almost nondispersive selected GR pulses near their cut-on frequency. Full wavefield measurements are conducted in time domain using a laser Doppler velocimeter to provide new insights into the GR near-cut-on scattering effects in the low vibroacoustic bandwidth.

Co, Fe, and Mn in La-perovskite oxides for low temperature thermochemical CO2 conversion

Abstract Perovskite oxides of the form ABO3 have shown substantial promise in reverse water gas shift chemical looping (RWGS-CL) process for low temperature thermochemical CO2 conversion to CO. Transition metals on the ‘B’ site of these perovskite oxides hold the key to tuning the material properties essential for efficient CO2 conversion. The role of Co, Fe and Mn in LaBO3 has been investigated through a combined theoretical and experimental approach. Intrinsic oxygen vacancy formation characteristics of these materials and the electronic charge distribution were explored via ab-initio density functional theory (DFT) simulations, while the microscale properties like crystallite size and CO2 conversion yield were probed experimentally. Through this multiscale study, the material properties that govern the stable and enhanced CO2 conversion phenomenon by Fe rich perovskites as opposed to Co and Mn rich phases are differentiated.