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Numerical Investigation on Thermal Performance Design of Cryogenic Compact Heat Exchangers with Serrated-Fin Channels

Traditional empirical formulas of Colburn heat transfer factors will lead to a design deviation for cryogenic heat exchangers. This paper employs the computational fluid dynamics (CFD) technique to numerically study the thermal performance of cryogenic compact heat exchangers (CCHEs). To obtain more precise convective heat transfer coefficients, the heat transfer performance of CCHE with serrated

Analysis of Fouling in Six-Start Spirally Corrugated Tubes

Fouling on heat exchanger surfaces can weaken the heat-transfer capability, increase the energy consumption, and even cause the failure of the whole system. In coaxial heat exchangers, spirally corrugated tubes perform better than smooth ones concerning heat transfer and antifouling. In this article, a parametric study on the antifouling performance of a six-start spirally corrugated tube is carri

GigaFRoST : The gigabit fast readout system for tomography

Owing to recent developments in CMOS technology, it is now possible to exploit tomographic microscopy at third-generation synchrotron facilities with unprecedented speeds. Despite this rapid technical progress, one crucial limitation for the investigation of realistic dynamic systems has remained: A generally short total acquisition time at high frame rates due to the limited internal memory of av

Making sense of circularity. An institutional logic perspective on circular business model transitions in incumbent firms.

Circular business models (CBMs) promise improved resource efficiency, value creation and retention. Still, CBM operationalization among large incumbents remains slow in practice. Yet, this plays a critical role in driving industry transformations towards sustainability. Prior research outlines challenges that incumbents encounter when operationalizing CBMs - yet remains fragmented and unable to ex

Acute Cardiovascular Effects of Hydrotreated Vegetable Oil Exhaust

Ambient air pollution is recognized as a key risk factor for cardiovascular morbidity and mortality contributing to the global disease burden. The use of renewable diesel fuels, such as hydrotreated vegetable oil (HVO), have increased in recent years and its impact on human health are not completely known. The present study investigated changes in cardiovascular tone in response to exposure to dil

3D SURFACE GENERATION FROM AERIAL THERMAL IMAGERY

Aerial thermal imagery has been recently applied to quantitative analysis of several scenes. For the mapping purpose based on aerial thermal imagery, high accuracy photogrammetric process is necessary. However, due to low geometric resolution and low contrast of thermal imaging sensors, there are some challenges in precise 3D measurement of objects. In this paper the potential of thermal video in

Implementation of the Recovery Guide in inpatient mental health services in Sweden-A process evaluation study

Background: Involving service users in inpatient care and recovery planning has gained interest worldwide. Our purpose was to evaluate the process of implementation of a coproduced Recovery Guide (RG) intervention in 22 inpatient wards in Sweden, in terms of context, implementation process and mechanisms of impact over 12 months.Methods: A mixed method design and a process evaluation framework wer

On the Prerequisites for Improving Prejudiced Ranking(s) with Individual and Post Hoc Interventions

In recruitment, promotion, admission, and other forms of wealth and power apportion, an evaluator typically ranks a set of candidates in terms of their perceived competence. If the evaluator is prejudiced, the resulting ranking will misrepresent the candidates’ actual ranking. This constitutes not only a moral and a practical problem, but also an epistemological one, which begs the question of wha

Revealing phase boundaries by weighted parametric structural refinement

Parametric Rietveld refinement from powder diffraction data has been utilized in a variety of situations to understand structural phase transitions of materials in situ. However, when analysing data from lower-resolution two-dimensional detectors or from samples with overlapping Bragg peaks, such transitions become difficult to observe. In this study, a weighted parametric method is demonstrated w

Resonant inelastic X-ray scattering of magnetic excitations under pressure

Resonant inelastic X-ray scattering (RIXS) is an extremely valuable tool for the study of elementary, including magnetic, excitations in matter. The latest developments of this technique have mostly been aimed at improving the energy resolution and performing polarization analysis of the scattered radiation, with a great impact on the interpretation and applicability of RIXS. Instead, this article

Allt sammantaget den bästa kandidaten : Om möjligheten till en reglerad sammanvägning av meriter som ett sätt att undvika osaklig meritvärdering vid antagning till forskarutbildningen

I texten undersöks förutsättningarna för att reglera sammanvägningen av meriter vid antagning till forskarutbildningen. Undersökningen motiveras av studier av meritvärdering inom andra områden som påvisar att just sammanvägningen av meriter tenderar att vara fördomsfull. För att konkretisera diskussionen så utgår texten från regler och praxis vid antagning till forskarutbildning vid Humanistiska o

Structure and stability of γ1-AuZn2.1 : A γ-brass-related complex phase in the Au-Zn System

γ1-AuZn2.1 in the Au-Zn binary system has been synthesized and its structure analyzed by single-crystal X-ray diffraction. It crystallizes in the trigonal space group P31m (No. 157) with ∼227 atoms per unit cell and represents a 3a × 3a × c superstructure of rhombohedrally distorted γ-Au5-x Zn8+y. The structure is largely tetrahedrally closed packed. The formation of γ1-AuZn2.1 can be understood w

A 19.5 GHz 28 nm CMOS Class-C VCO with Reduced 1/f Noise Upconversion

Class-C operation is leveraged to implement a K-band CMOS VCO where the upconversion of the 1/f noise from the core transistors is robustly contained at a minimal level. Implemented in a bulk 28 nm CMOS technology,the VCO shows a phase noise as low as -108.5 dBc/Hz at 1 MHz offset (-83 dBc/Hz at 100 kHz offset) from the 19.5 GHz carrier,while consuming 14.4 mW and featuring a 12% tuning range.

An 11 GHz-Bandwidth Variable Gain Ka-Band Power Amplifier for 5G Applications

A Ka-band,32-43 GHz,differential power amplifier (PA) for millimeter wave applications is presented. The PA is a three stage design with a nominal gain of 36 dB. A device periphery ratio of 1:2:4 is adopted for pre-driver,driver and final stage,respectively. To enable use of 2.7 V supply,a cascode topology was employed in all three stages. The input is 80 ω differential and the output load is 50 ω

Virtual Network Embedding for Collaborative Edge Computing in Optical-Wireless Networks

As an open integrated environment deployed with wired and wireless infrastructures, the smart city heavily relies on the wireless-optical broadband access network. Smart home data are usually sent to neighbor optical network units (ONUs) through front-end wireless mesh networks (WMNs) and finally reach the optical line terminal (OLT) for decision making via the passive optical network (PON) backha

Assessment of Free Gas in the Tibial Condyle Bone of the Human Knee by Diode Laser Spectroscopy with Possible Application to Arthrosis Diagnostics

The gas in scattering media absorption spectroscopy (GASMAS) technique was used to investigate the possible presence of free gas pores in human condyle bones, extracted from the tibia in knee revision surgical procedures in response to arthrosis development. Following earlier studies showing free gas presence in femoral head bones, decaying because of inadequate blood flow, we investigated condyle

Modeling the morphology of self-assisted GaP nanowires grown by molecular beam epitaxy

The morphologies of self-assisted GaP nanowires grown by gas source MBE in regular arrays on silicon substrates are modeled by a kinetic equation for the nanowire radius versus the position along the nanowire axis. The most important growth parameter that governs the nanowire morphology is the V/III flux ratio. Sharpened nanowires with a stable radius equal to only 12 nm at a V/III flux ratio of 6

Impact of DOI in a Clinical SPECT/MRI System : A Simulation Study

A novel SPECT/MRI scanner has been modelled and tested here using Monte Carlo simulation software, SIMIND. The INSERT SPECT/MRI system faces challenges with event reconstruction due to photon depth of interaction. The novel SPECT system is subject to parallax errors due to its crystal size and slit aperture collimator. We present a simple measure of the DOI errors through SIMIND experiments; by mo