Search

We introduce a new approach for solving quantum many-body systems called wave function matching. Wave function matching transforms the interaction between particles so that the wave functions at short distances match that of an easily computable interaction. This allows for calculations of systems that would otherwise be impossible due to problems such as Monte Carlo sign cancellations. We apply the method to lattice Monte Carlo simulations of light nuclei, medium-mass nuclei, neutron matter, and nuclear matter. We use interactions at next-to-next-to-next-to-leading order in the framework of chiral effective field theory and find good agreement with empirical data. These results are accompanied by new insights on the nuclear interactions that may help to resolve long-standing challenges in accurately reproducing nuclear binding energies, charge radii, and nuclear matter saturation in ab initio calculations., 24 pages, 10 figues, 13 tables

We report the characteristics of AlN epilayers grown directly on cylindrical-patterned sapphire substrates (CPSS) by hydride vapor-phase epitaxy (HVPE). To evaluate the effect of CPSS, we analyzed the threading dislocation densities (TDDs) of AlN films grown simultaneously on CPSS and flat sapphire substrate (FSS) by transmission electron microscopy (TEM). The corresponding TDD is measured to be 5.69 x 108 cm−2 for the AlN sample grown on the CPSS that is almost an order of magnitude lower than the value of 3.43 × 109 cm−2 on the FSS. The CPSS contributes to reduce the TDs originated from the AlN/sapphire interface via bending the TDs by lateral growth during the coalescence process. In addition, the reduction of direct interface area between AlN and sapphire by CPSS reduce the generation of TDs.

Conservation of resources (COR) theory proposes that mistreatment by customers (termed “customer mistreatment”) can deplete employees’ resources, lessen their ability to regulate their behaviors, and result in them engaging in customer-directed deviant behavior. However, COR has been criticized for its lack of precision regarding how this process unfolds. Integrating the person-situation interactionist perspective with COR theory, the present paper aims to provide a deeper understanding of COR theory by explicating how individual characteristics and work context—namely, psychological detachment and supervisory unfairness—can combine to attenuate/exacerbate the relationship between customer mistreatment and employees’ customer-directed deviant behavior. Using a multilevel field study with 1,092 daily-based surveys among 157 Korean call-center representatives, our results show that frontline employees’ emotional exhaustion mediates the relationship between customer mistreatment and customer-directed deviant behavior that occurs on the next working day. When faced with customer mistreatment, employees with lower (vs. higher) psychological detachment were more likely to be emotionally exhausted and engage in customer-directed deviant behavior on the next working day. Moreover, their emotional exhaustion predicted customer-directed deviant behavior more so when their supervisors treated them unfairly (vs. fairly). Taken together, the results show that the mediating effect of emotional exhaustion was strongest among employees with low (vs. high) psychological detachment and who reported more (vs. less) supervisory unfairness. Theoretical, methodological, and practical implications as well as directions for future research are discussed.

Customer injustice has received considerable attention in the field of organizational behavior because it generates a variety of negative outcomes. Among possible negative consequences, customer-directed sabotage is the most common reaction, which impacts individuals’ well-being and the prosperity of organizations. To minimize such negative consequences, researchers have sought to identify boundary conditions that could potentially attenuate the occurrence of customer-directed sabotage. In this study, we explore potential attenuation effects of emotional stability and attentiveness on the customer injustice–sabotage linkage. The results showed emotional stability and attentiveness moderate the relationship between customer injustice and customer-directed sabotage. Specifically, the representatives with higher (vs. lower) emotional stability or higher (vs. lower) attentiveness are less likely to engage in customer-directed sabotage when they experience customer injustice. Moreover, there is a three-way interaction among daily customer injustice, emotional stability, and attentiveness that predicts daily customer-directed sabotage. Theoretical and practical contributions, limitations, and directions for future development are also discussed.

It is often computationally advantageous to model space as a discrete set of points forming a lattice grid. This technique is particularly useful for computationally difficult problems such as quantum many-body systems. For reasons of simplicity and familiarity, nearly all quantum many-body calculations have been performed on simple cubic lattices. Since the removal of lattice artifacts is often an important concern, it would be useful to perform calculations using more than one lattice geometry. In this work we show how to perform quantum many-body calculations using auxiliary-field Monte Carlo simulations on a three-dimensional body-centered cubic (BCC) lattice. As a benchmark test we compute the ground state energy of 33 spin-up and 33 spin-down fermions in the unitary limit, which is an idealized limit where the interaction range is zero and scattering length is infinite. As a fraction of the free Fermi gas energy $E_{\rm FG}$, we find that the ground state energy is $E_0/E_{\rm FG}= 0.369(2), 0.371(2),$ using two different definitions of the finite-system energy ratio. This is in excellent agreement with recent results obtained on a cubic lattice \cite{He:2019ipt}. We find that the computational effort and performance on a BCC lattice is approximately the same as that for a cubic lattice with the same number of lattice points. We discuss how the lattice simulations with different geometries can be used to constrain the size lattice artifacts in simulations of continuum quantum many-body systems., 13 pages, 7 figures

Clinical use of the chemotherapeutic agent vincristine (VCR) is limited by chemotherapy-induced peripheral neuropathy (CiPN). A new formulation of VCR encapsulated by nanoparticles has been proposed and developed to alleviate CiPN. We hypothesized in nonclinical animals that the nanoparticle drug would be less neurotoxic due to different absorption and distribution properties to the peripheral nerve from the unencapsulated free drug. Here, we assessed whether VCR encapsulation in nanoparticles alleviates CiPN using behavioral gait analysis (CatWalk), histopathologic and molecular biological (RT-qPCR) approaches. Adult male C57BL/6 mice were assigned to 3 groups (empty nanoparticle, nano-VCR, solution-based VCR, each n = 8). After 15 days of dosing, animals were euthanized for tissue collection. It was shown that intraperitoneal administration of nano-VCR (0.15 mg/kg, every other day) and the empty nanoparticle resulted in no changes in gait parameters; whereas, injection of solution-based VCR resulted in decreased run speed and increased step cycle and stance ( P < 0.05). There were no differences in incidence and severity of degeneration in the sciatic nerves between the nano-VCR-dosed and solution-based VCR-dosed animals. Likewise, decreased levels of a nervous tissue-enriched microRNA-183 in circulating blood did not show a significant difference between the nano- and solution-based VCR groups ( P > 0.05). Empty nanoparticle administration did not cause any behavioral, microRNA, or structural changes. In conclusion, this study suggests that the nano-VCR formulation may alleviate behavioral changes in CiPN, but it does not improve the structural changes of CiPN in peripheral nerve. Nanoparticle properties may need to be optimized to improve biological observations.

We study breakup of the deuteron induced by neutrinos in the neutral $\nu d\to \nu np$, $\bar{\nu} d\to \bar{\nu} np$ and the charged $\bar{\nu} d\to e^+ n n$, $\nu d\to e^- pp$ processes. Pionless effective field theory with dibaryon fields is used to calculate the total cross sections for neutrino energies $E_\nu$ from threshold to 20 MeV. Amplitudes are expanded up to next-to-leading order, and the partial wave is truncated at $P$-waves. The Coulomb interaction between two protons is included nonperturbatively in the reaction amplitudes, and an analytic expression of the amplitudes is obtained. The contribution of the next-to-leading order to the total cross section is in the range of 5.2$-$9.9\% in magnitude, and that of the $P$-wave is 2.4$-$2.8\% at $E_\nu = 20$ MeV. Uncertainty arising from an axial isovector low-energy constant is estimated to be on the order of 1\%., Comment: 25 pages, 5 figures

We study the uncertainty stemming from different theoretical models in the spectroscopic factors extracted from experiments. We use three theoretical approaches, the distorted wave Born approximation (DWBA), the adiabatic distorted wave approximation (ADWA) and the continuum discretized coupled-channels method (CDCC), and analyze the 12C(d, p)13C, 14C(d, p)15C reactions. We find that the uncertainty associated with the adopted theoretical models is less than 20%. We also investigate the contribution from the remnant term and observe that it gives less than 10% uncertainty. We finally make an attempt to explain the discrepancy in the spectroscopic factors of $$^{17}C(\frac{3}{2}^+)$$ between the ones extracted from experiments and from shell model calculations by analyzing the 16C(d, p)17C reaction.

This study was conducted according to the method presented in the Republic of Korea Pharmacopoeia 11th Revision, aseptic test method to evaluate the suitability of sterilization for a sterile needle (4 Pin Multi-needle). In this study, four tests were conducted: sterility test, cytotoxicity test, acute toxicity test, skin sensitization test. First, in the aseptic test, the microorganism was not proliferated in the aseptic test of the medium. As a result of the performance test of the medium, it was confirmed that the microorganism developed within 3 days and the fungus was evident within 5 days. Based on this, it was confirmed that the medium was suitable, and as a result of the aseptic test, the development of microorganisms was not observed during the total culture period. Based on these results, tests were conducted which were confirmed to be suitable for aseptic testing because the development of bacteria on the provided samples was not recognized. For cytotoxicity tests ISO10993-5; 2009 (Biological Evaluation of Medical Devices, Part 5: Test for in vitro Cytotoxicity). As a result, the MEM eluate of the test substance caused very slight cytotoxicity to the fibroblasts of the mouse and was judged to be Grade 1 (Slightly cytotoxic) according to the judgment standard of ISO 10993-5. On the other hand, solvent control, negative control and positive control showed the expected results on the test. Acute Toxicity Test Results: It was judged that there was no systemic toxicity change when ICR mice were treated with 50 mL/kg B.W. of the eluate of sterile injectable needle for 72 hours. Skin sensitization test result: The Hartley guinea pig was evaluated as a substance which is evaluated as a substance which does not induce any skin reaction when skin sensitization is applied to the dissected material of the sterile injectable needle and is weak in skin sensitivity. Based on the above tests, we will study the stability and efficacy of more reliable medical devices based on the verification and performance of medical devices.

Generally, heat exchanger is a thermodynamic system which has been employed to transfer thermal energy between two or more fluids, between a solid surface and a fluid, or between solid particulates and a fluid, at different temperatures and in thermal contact. Recently, the growing requirements to save energy and reduce overall environmental impacts has placed greater emphasis on the use of heat exchangers with better thermal efficiency. Therefore, the plate-type heat exchanger that uses metal plates to transfer heat between two fluids has a major advantage over a conventional heat exchanger in which the fluids are exposed to a much larger surface area because the fluids spread out over the plates. However, fouling with the flow of fluid for a long period occurs on the plate surface. So, it might be necessary to carry out numerical simulation for the hot and cold fluid flow model which can reflect the real situation of hot and cold fluid heat transfer. In this paper, plate-type heat exchanger is simulated which based on the computational fluid dynamics method. The calculated model is established for fluid flow and heat transfer in cold and hot flow channels of a chevron-type plate-type heat exchanger. The flow pattern and heat transfer effect of the cold and hot fluids are analyzed under the water-to-water heat transfer by using the simulation software, ANSYS. At the same time, 3D numerical model of the local computation domains for the plate-type heat exchanger are simulated at different parameters which included the corrugated angle, corrugated depth and corrugated pitch. With the development of CFD(Computational Fluid Dynamics) technology, numerical guidance can be provided for the improvement of plate-type heat exchanger and optimization of the design.

International audience; The parity-violating neutron spin rotation in He4 is studied at vanishing incident neutron energy limit. Calculations have been realized by solving five-body Faddeev-Yakubovsky equations in configuration space employing modern strong-interaction Hamiltonian based on chiral perturbation theory including three-nucleon force. Parity-violating nucleon-nucleon interaction of the Desplanques, Donoghue, and Holstein model is employed. An implication of the recent theoretical large-Nc estimation of weak couplings [Phillips , Phys. Rev. Lett. 114, 062301 (2015)PRLTAO0031-900710.1103/PhysRevLett.114.062301] is also discussed.

We report herein on the design, synthesis and biological activity of Ru-based self-assembled supramolecular bowls as a potent anticancer therapeutic in human hepatocellular cancer. The potent complex induces production of reactive oxygen species (ROS) by higher fatty acid β-oxidation and down-regulation of glucose transporter-mediated pyruvate dehydrogenase kinase 1 via reduced hypoxia-inducible factor 1α. Also, overexpressed acetyl-CoA activates the tricarboxylic acid cycle and the electron transport system and induces hypergeneration of ROS. Finally, ROS overexpressed through this pathway leads to apoptosis. Furthermore, we demonstrate that the naphthalene derived molecular bowl activates classical apoptosis via crosstalk between the extrinsic and intrinsic signal pathway. Our work into the mechanism of Ru-based self-assembled supramolecular bowls can provide valuable insight into the potential for use as a promising anticancer agent.

The present studies were aimed at formulating AZD2811-loaded polylactic acid-polyethylene glycol (PLA-PEG) nanoparticles with adjustable release rates without altering the chemical structures of the polymer or active pharmaceutical ingredient (API). This was accomplished through the use of a hydrophobic ion pairing approach. A series of AZD2811-containing nanoparticles with a variety of hydrophobic counterions including oleic acid, 1-hydroxy-2-naphthoic acid, cholic acid, deoxycholic acid, dioctylsulfosuccinic acid, and pamoic acid is described. The hydrophobicity of AZD2811 was increased through formation of ion pairs with these hydrophobic counterions, producing nanoparticles with exceptionally high drug loading-up to five fold higher encapsulation efficiency and drug loading compared to nanoparticles made without hydrophobic ion pairs. Furthermore, the rate at which the drug was released from the nanoparticles could be controlled by employing counterions with various hydrophobicities and structures, resulting in release half-lives ranging from about 2 to 120h using the same polymer, nanoparticle size, and nanoemulsion process. Process recipe variables affecting drug load and release rate were identified, including pH and molarity of quench buffer. Ion pair formation between AZD2811 and pamoic acid as a model counterion was investigated using solubility enhancement as well as nuclear magnetic resonance spectroscopy to demonstrate solution-state interactions. Further evidence for an ion pairing mechanism of controlled release was provided through the measurement of API and counterion release profiles using high-performance liquid chromatography, which had stoichiometric relationships. Finally, Raman spectra of an AZD2811-pamoate salt compared well with those of the formulated nanoparticles, while single components (AZD2811, pamoic acid) alone did not. A library of AZD2811 batches was created for analytical and preclinical characterization. Dramatically improved preclinical efficacy and tolerability data were generated for the pamoic acid lead formulation, which has been selected for evaluation in a Phase 1 clinical trial (ClinicalTrials.gov Identifier NCT 02579226). This work clearly demonstrates the importance of assessing a wide range of drug release rates during formulation screening as a critical step for new drug product development, and how utilizing hydrophobic ion pairing enabled this promising nanoparticle formulation to proceed into clinical development.

The multifoci perspective of justice proposes that individuals tend to target their (in)justice reactions toward the perceived source of the mistreatment. Empirical support for target-specific reactions, however, has been mixed. To explore theoretically relevant reasons for these discrepant results and address unanswered questions in the multifoci justice literature, the present research examines how different justice sources might interactively predict target-specific reactions, and whether these effects occur as a function of moral identity. Results from a sample of North American frontline service employees (N = 314, Study 1) showed that among employees with lower levels of moral identity, low supervisor justice exacerbated the association between low customer justice and customer-directed sabotage, whereas this exacerbation effect was not observed among employees with higher levels of moral identity. This 3-way interaction effect was replicated in a sample of South Korean employees (N = 265, Study 2).

Gedatolisib, a PI3K/mTOR dual inhibitor delivered intravenously, is in early clinical trials in women with metastatic ER+ breast cancer. We reasoned that the therapeutic index could be further maximized by encapsulation of gedatolisib in nanoparticles (NP), thereby providing longer half-life, sustained release, blunting of Cmax and associated toxicity, asymmetric distribution to leaky tumor vasculature and the possibility of less frequent dosing. PF-07034663 is a polymeric NP encapsulating gedatolisib, targeted to prostate-specific membrane antigen (PSMA), a clinically validated tumor antigen expressed on prostate cancer cells and the neovasculature of some nonprostate solid tumors. Studies in mice, rats, and cynomolgus monkeys demonstrated that the terminal half-life of PF-07034663 following intravenous administration increased by ~1.5 fold and the Cmax of released gedatolisib from PF-07034663 decreased by ~75 fold compared to gedatolisib delivered by the same route. Gedatolisib released from PF-07034663 exhibited markedly enhanced intratumoral accumulation compared to gedatolisib (~40 fold), indicating enhanced tissue delivery and/or prolonged retention. In exploratory toxicology studies, PF-07034663 caused no hyper-insulinemic spike in rats, in contrast to gedatolisib. To evaluate the antitumor activity of PF-07034663, we performed tumor growth inhibition (TGI) studies in PSMA-positive C4-2 prostate and in PSMA-negative MDAMB361 ER+ breast and A549 lung xenograft tumor models. In the C4-2 model, PF-07034663 showed dose-dependent antitumor efficacy as a single agent, and, in combination with enzalutamide, exhibited enhanced activity leading to tumor regressions. PF 07034663 also exhibited prolonged, dose-dependent inhibition of phosphorylation of S6 (pS6) in the C4-2 model compared to gedatolisib. Interestingly, increased pharmacodynamics (PD) responses compared to gedatolisib were not restricted to PSMA-positive tumors. Moreover, TGI responses were increased in the PSMA-negative A549 lung cancer model, relative to those observed with gedatolisib. PF 07034663 treatment in spontaneous prostate tumors in PTENnullp53mut GEM mice and in subcutaneous allografts of these spontaneous tumors in wild-type mice showed that treatment of PF-07034663 caused similar pS6 inhibition in both models, suggesting that PD modulation is independent of tumor origin or milieu and is less likely due to altered enhanced permeability and retention (EPR) effect. Taken together, PF-07034663 exhibits potential for improved tolerability, sustained tumor PK, prolonged PD modulation, and less frequent dosing schedule compared to gedatolisib. These results support further exploration of gedatolisib in tumor-targeted or non-tumor-targeted nanoparticles in clinical trials as a promising vehicle for delivery of PI3K/mTOR inhibitors to advanced cancer patients. Citation Format: Lianglin Zhang, Gabriel Troche, Ravi Visswanathan, Wenhu Huang, Young-Ho Song, Mary E. Spilker, Zhenxiong Wang, Hui Wang, Anand Giddabasappa, Louise Cadzow, Susan Low, Greg Troiano, Jennifer Lafontaine, Valeria Fantin, Robert T. Abraham, Shubha Bagrodia. Development of a nanoparticle containing the PI3K/mTOR dual Inhibitor, gedatolisib, for cancer therapy [abstract]. In: Proceedings of the AACR Special Conference on Targeting PI3K/mTOR Signaling; 2018 Nov 30-Dec 8; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Res 2020;18(10_Suppl):Abstract nr B25.

Considerable research has documented the detrimental impact of customer mistreatment on service employees’ well-being and behaviors. Extending this research, we have integrated the conservation of ...

A molecular Solomon link was synthesized in high yield through the template-free, coordination-driven self-assembly of a carbazole-functionalized donor and a tetracene-based dinuclear ruthenium(II) acceptor. The doubly interlocked topology was realized by a strategically chosen ligand which was capable of participating in multiple CH⋅⋅⋅π and π-π interactions, as evidenced from single-crystal X-ray analysis and computational studies. This method is the first example of a two-component self-assembly of a molecular Solomon link using a directional bonding approach. The donor alone was not responsible for the construction of the Solomon link, and was confirmed by its noncatenane self-assemblies obtained with other similar ruthenium(II) acceptors.

Due to the popularity of location-based services, the amount of generated spatial data in daily life has been dramatically increasing. Therefore, spatial database outsourcing has become popular for data owners to reduce the spatial database management cost. The most important consideration in database outsourcing is meeting the privacy requirements and guarantying the integrity of the query result. However, most of existing database transformation techniques do not support both of the data privacy and integrity of the query result. To solve this problem, we propose a spatial data transformation scheme that utilizes the shearing transformation with rotation shifting. In addition, we described the attack models to measure the data privacy of database transformation schemes. Finally, we demonstrated through the experimental evaluations that our scheme provides high level of data protection against different kinds of attack models, compared to the existing schemes, while guaranteeing the integrity of the query result sets.

A hollow iridium-cornered prismatic cage was self-assembled without the assistance of any template. The cage was found to be capable of encapsulating heteroguest's triplet in its perfect sized cavity, producing the first demonstration of quintuple structure by an octahedral metal cornered prismatic cage.

Spin polarization observables of the deuteron photodisintegration at low energies are studied in a pionless effective field theory up to next-to-next-to-leading order (NNLO). The total and differential cross sections, induced neutron polarization $P_{y'}$, and tensor analyzing powers $T_{20}$ and $T_{22}$ of the process are calculated at photon energies from the breakup threshold to 20~MeV. We find that the NNLO corrections in the cross sections and $P_{y'}$ converge well whereas they turn out to be important contributions in $T_{20}$ and $T_{22}$. We discuss the discrepancy between theory and experiment in $P_{y'}$ still persisting as well as an implication of our result to the first measurement of $T_{20}$ at low energies in the HIGS facility., To be published in Physical Review C

International audience; Determination of the proper power-counting scheme is an important issue for the systematic application of Chiral Effective Field Theory in nuclear physics. We analyze the cutoff dependence of three-nucleon observables (the neutron-deuteron scattering lengths and the triton binding energy) at the leading and next-to-leading orders of a power counting that ensures order-by-order renormalization in the two-nucleon system. Our results confirm that, as usually assumed in the literature, three-body forces are not needed for renormalization of the three-nucleon system up to next-to-leading order.

The purpose of t his study is to get the formulas of condensation heat transfer coefficient and pres-sure drop about the water to develop design program for plate type heat exchangers. The single phase flow of cold side was calculated with the correlation of Ko. Condensation heat transfer coefficient model proposed by Annaiev was used and Lockhart model was used to analyze the pressure drop. The calculation algorithm was proposed to calculate heat transfer rate and pressure drop simultaneously. The prediction errors remained within 20% compared to the commercial code in the working range of the plate heat exchangers. Keywords: Condensation Heat Transfer Coefficient, Heat Transfer Coefficient, Pressure Drop, Plate Heat Exchangers. 기호설명  : 밀도 보정계수 : 마찰인자(Friction Factor) : 중력가속도[  ]  : 채널 유속 [  ]  : 응축열전달계수 [  ]  : 단상대류열전달계수 [  ] : 엔탈피  : 전도열전달계수   : 유효길이 : 넛셀 수∆: 압력강하 Pr : 프란틀 수 ″ : 열 유속    : 레이놀즈 수∆  : 대수평균온도차 [] : 총괄열전달계수 

Thick InGaN alloys with high In content are essential for emerging InGaN photovoltaic applications. By applying a compositionally graded structure, various thicknesses of InGaN layers were grown using metal organic chemical vapor deposition. We could obtain pseudomorphic and highly strained layer even upto 100 nm of InGaN film as confirmed by X-ray reciprocal space mapping and Raman spectra. To probe the validity of those InGaN layers for solar cell applications, optical transmittance measurements were carried out and absorption properties were compared.

We report hybrid n-ZnO/i-InGaN/p-GaN solar cells in which the n-GaN layer of n-GaN/i-InGaN/p-GaN solar cell was replaced with n-type ZnO. In this study, inverted structures were used for hybrid ZnO/nitride solar cells where p-type GaN was first grown on sapphire substrate, followed by i-InGaN and n-ZnO layers. The as-fabricated device showed high series resistance and low energy conversion efficiency due to the formation of damaged p-GaN region during dry etching. On the other hand, formation of microrods on the p-GaN eased the removal of the damaged p-GaN resulting in significantly lowered series resistance and enhanced energy conversion efficiency. (a) n-ZnO/i-InGaN/p-GaN solar cell structure without microrods, (b) n-ZnO/i-InGaN/p-GaN solar cell structure with microrods, and (c) magnified image of the dashed box on (b).

The periodic beveled micro-rods (BMRs) were constructed on the emission surface of GaN-based vertical light-emitting diodes (VLEDs) in order to improve the light-extraction efficiency. It was experimentally demonstrated that the light output power of the VLEDs with a periodic BMR (BMR-VLED) were enhanced about 15.6%, compared with that of the VLEDs with randomly textured surface (RT-VLED) at an injection current of 350 mA. This finding indicates that the photons emitted from the active layer were well out-coupled at an n-GaN surface having a periodic BMR structure, resulting in an increase in the probability of escaping from the VLED structure.

We report on enhanced efficiency of ultraviolet vertical light-emitting diodes (VLEDs) with interference between the reflective mirror and the multiple quantum well. The dimensions of the cavity are fixed at 30 nm for the p-AlGaN layer, while various thicknesses of p-GaN from 60 nm to 140 nm were used. The light output power of the VLED in constructive compared with destructive interference condition increased by 23.9% at 350 mA. These improvements could be attributed to the predominant constructive interference of vertical radiation due to an optical cavity with optimal p-GaN thickness.

In this study, we have fabricated 375-nm-wavelength InGaN/AlInGaN nanopillar light emitting diodes (LED) structures on c-plane sapphire. A uniform and highly vertical nanopillar structure was fabricated using self-organized Ni/SiO2 nano-size mask by dry etching method. To minimize the dry etching damage, the samples were subjected to high temperature annealing with subsequent chemical passivation in KOH solution. Prior to annealing and passivation the UV nanopillar LEDs showed the photoluminescence (PL) efficiency about 2.5 times higher than conventional UV LED structures which is attributed to better light extraction efficiency and possibly some improvement of internal quantum efficiency due to partially relieved strain. Annealing alone further increased the PL efficiency by about 4.5 times compared to the conventional UV LEDs, while KOH passivation led to the overall PL efficiency improvement by more than 7 times. Combined results of Raman spectroscopy and X-ray photoelectron spectroscopy (XPS) suggest that annealing decreases the number of lattice defects and relieves the strain in the surface region of the nanopillars whereas KOH treatment removes the surface oxide from nanopillar surface.

Time reversal invariance violating (TRIV) effects in low energy physics could be very important in searching for new physics, being complementary to neutron and atomic electric dipole moment (EDM) measurements. In this relation, we discuss a sensitivity of some TRIV observables to different models of time-reversal (CP) violation and their dependencies on nuclear structure. As a measure of a sensitivity of TRIV effects to the value of TRIV nucleon coupling constant, we introduce a coefficient of a “discovery potential”, which shows a possible factor for improving the current limits of the EDM experiments by measuring nuclear TRIV effects.

In this paper, we propose a capacity modeling method for Bluetooth based LBSs (Location Based Services) between Bluetooth APs(Access Points) and mobile phones. In order to do this, we consider the entrance and exit of the users to and from the AP. Using parameters such as the connection time, data transmission time and number of users in the AP zone, we analyze the capacity of a Bluetooth AP using an appropriate queuing model. The required number of APs in a certain zone is estimated from the number of users in the zone using the proposed queuing model. By performing simulations and experiments, the validity and applicability of the proposed method are verified.

Time reversal invariance violating and parity conserving effects for low-energy elastic neutron-deuteron scattering are calculated for meson exchange and effective field theory type potentials in a distorted wave-born approximation using realistic hadronic wave functions, obtained by solving three-body Faddeev equations in configuration space.

A partial screening of nucleon electric dipole moments (EDMs) in nuclear systems, which is related to the Schiff mechanism known for neutral atomic systems, is discussed. It is shown that the direct contribution from the neutron EDM to the deuteron EDM is partially screened by about 1% in a zero-range approximation calculation., Comment: 11 pages. Version to appear in Phys. Rev. C

Heat exchanger has been widely used in the industry which needs energy transport, and the application of the plate type heat exchanger having high efficiency has been greatly increased. In this studymain design parameters are analyzed and new equations are induced. The induced formulation was compared with a commercial program in order to design an optimal heat exchanger. The equations of heat transfer coefficient and pressure drop for Chevron angles are introduced as functions of Reynolds number.The program implemented the equations is tested with Chevron angle variation. The results show that theconvective heat transfer coefficients take errors within 8% and the pressure drops have errors within 5%in the analysis conditions. Key words: Convective heat transfer coefficient , Overall heat transfer coefficient, Pressure drop, Chevron angle †교신저자(한국해양대학교 기계에너지시스템공학부, E-mail: khpark@hhu.ac.kr, Tel: 051-410-4367)1 한국해양대학교 기계공학과 대학원 , E-mail: goj2132@nate.com, Tel: 051-410-49532 ㈜대원열판, E-mail: yhsong@dhpeng.com, Tel: 055-338-4301

DWTT (Drop Weigh Tearing Test) is one critical method that can exhibit the fracture properties of line pipe steel, since it estimates the properties with real pipe steel. In this study, the ductile portion, inverse fracture ratio and absorbed energy of API X65 and X70 line pipe steels were estimated with temperature variation. Both steels showed that the ratio of ductile area and absorbed energy were decreased with respect to decreasing the test temperature. However, while the ductile fracture behavior exhibited until -40 ℃ for the X70 steel, but it showed until -30℃ for the X65 steel. The fracture properties were discussed with respect to test temperatures.Key words : linepipe steel, DWTT, absorbed energy † I. 서 론 최근 천연자원이 개발되면서, 실생활에 밀접하게 영향을 주는 원유와 천연가스의 생산지로부터 소비지로의 수송이 중요하게 대두되고 있다[1-8]. 현재는 많은 양의 원유와 천연가스 (특히 천연가스는 LNG로 액화시켜 공급)가 선박 수송 및 라인파이프강(line † 교신저자:jsphb@hanbat.ac.krpipesteels) 을 통해 공급되고 있다. 하지만, 천연자원의 매장량의 일부는 극지방과 같은 한랭지, 심해저 등에 매장되어 있기 때문에, 이러한 지역의 자원들은 선박으로 수송하는 것은 한계가 있다[1,7,9]. 그러므로 라인파이프강을 통한 공급 개발이 증가하고 있다. 그에 따라서, 원유와 천연가스의 수송효율을 높이기 위해, 고압에서도 잘 견디는 높은 강도의 라인파이프강을 요구하고 있고, 많은 양의 원유와 천연가스를 수송하기 위해 배관의 크기는 점점 커지고 있다.KIGAS Vol. 16, No. 3, June, 2012(Journal of the Korean Institute of Gas)

This paper is to analyze the smoke characteristics of wood flour-HDPE composites. The wood flour-HDPE composites were manufactured by modular co-rotating twin screw extruder. In order to analyze smoke characteristics, Cone calorimeter tests(by ISO 5660-2) and smoke density tests(by ASTM E 662) were performed. The specimens for these tests were differently made by adding flame retardants. The results of cone calorimeter test showed that adding flame retardants specimens are lower total smoke release, total smoke production than those of wood flour-HDPE composite. Also the results of smoke density test showed that adding flame retardants specimens are lower initial smoke data and maximum specific optical density than those of wood flour-HDPE composite. The most effective flame retardant is magnesium dihydroxide to decrease smoke characteristics.

Mo-Si-B alloys have been received an attention due to the high temperature strength and phase stability. However, the nature of poor oxidation resistance often limits the application of the alloy system. In order to resolve the poor oxidation resistance of the alloy system, in this study, the oxidation behaviors of Si diffusion coated Mo-Si-B alloys have been investigated in order to identify the underlying mechanism for the effect of the constituent of the phase combination of Mo-Si-B alloys. The oxidation tests performed at 1100 °C show that the produced MoSi2 phase, as a result of the coatings, give an excellent oxidation resistance at prolonged high temperature exposure in air. The oxidation behaviors of uncoated and Si coated Mo-Si-B alloys have been discussed in terms of microstructural observations during oxidation tests.