A feasibility study of a novel combined solar concentration/wind augmentation system

For deeper understanding of the formation of elite at enterprises, the article proposed to consider a hierarchy of an enterprise from the point of view of two main factors: social and organizational-occupational status.It was determined that the status of an individual in the structure of an enterprise is an integral characteristic, based on the synthesis of hierarchical aspects of organizational structure of an enterprise. It was noted that the current establishment at an enterprise is characterized by a position of an individual in the system of interpersonal relations, his/her rights, duties and privileges.As a social status, we suggested the amount of power, social perspective of the status and prestige of an individual. It was emphasized that the organizational-occupational status of the elite is characterized by different levels of management.It was noted that at enterprises each element serves to meet corresponding challenges to achieve a common goal. It was concluded that the structural-functional approach provides the possibility of further system analysis of the elite at enterprises.В статье рассмотрены проблемы становления элиты на современном предприятии с позиции социального и организационно-профессионального статуса. Определено, что статус индивида в структуре предприятия является интегральной характеристикой, основу которой составляет синтез иерархических аспектов организационной структуры предприятия. Отмечено, что современный истеблишмент на предприятии характеризуется позицией индивида в системе межличностных отношений, его прав, обязанностей и привилегий.У статті розглянуто проблеми становлення еліти на сучасному підприємстві з позиції соціального та організаційно-професійного статусу. Визначено, що статус індивіда в структурі підприємства є інтегральною характеристикою, основу якої складає синтез ієрархічних аспектів організаційної структури підприємства. Зазначено, що сучасний істеблішмент на підприємстві характеризується позицією індивіда у системі міжособистих відносин, його прав, обов’язків та привілеїв

Effect of different carrier gases on productivity enhancement of a novel multi-effect vertical concentric tubular solar brackish water desalination device

A novel multi-effect vertical concentric tubular solar brackish water desalination device is introduced in present study. The device consists of four closely spaced concentric pipes, in which the feed water gets preheated by hot brine water to guarantee the evaporation efficiency. An experimental investigation and analytical analysis were carried out to signify the effect of carrier gas-water vapor mixture on productivity enhancement of the device. Different carrier gases were used in the performance evaluation: carbon dioxide, helium, nitrogen, oxygen, air and argon. The water yield and the top/bottom temperature values of condensation surface of the device with different carrier gases were tested. In addition, the present investigation is presented an approach to predict the theory yield based on the internal heat and mass transfer mechanism. The experimental results indicate that, when the heating temperature is 80 °C and the carrier gas is helium, the water productivity rate can reach to 1.19 kg/h. It is increased by 30.76% than the carrier gas of air. The numerical results had been calculated and a consistent agreement with the experimental results had been obtained of different operation temperatures. The Dv under different heating temperature were obtained according to the experimental results

Application of the shear wave elastography in the assessment of carotid body tumors: A preliminary study

ObjectivesTo evaluate the elasticity of carotid body tumors (CBTs) by two-dimensional shear wave elastography (SWE).Methods22 pathologically or clinically confirmed CBTs in 16 patients were scanned by SWE. The maximum elasticity value (Emax) and its standard deviation (SDmax) in kPa and m/s for CBTs were obtained by placing a round ROI (2-3 mm) on the stiffest region of the CBTs. Elasticity value was compared between hard and soft groups at manual palpation, benign and malignant groups and among three Shamblin types. The area under the receiver operating characteristic curve (AUC) analysis was performed to evaluate the performance of SWE in the malignancy prediction of CBTs. Sensitivity, specificity and accuracy were calculated. The cut-off value was obtained by using the Youden index.ResultsThere were 19 benign CBTs and 3 malignant CBTs. Emax (kPa and m/s) and SDmax (kPa) were significantly higher in the hard group than in the soft group at manual palpation (P<0.05); The distribution of Emax in kPa and m/s and SDmax in kPa were different in the three Shamblin types (P<0.05), Emax (kPa and m/s)increased from shambling I to Shambling II and Shambling III; Emax (kPa and m/s) were significantly higher in the malignant CBTs than in the benign ones (P<0.05). Emax in kPa and m/s had the similar AUC value (AUC=0.947, P=1.0000) for the prediction of malignant CBTs. Emax in kPa with the cut-off 124.9kPa showed a sensitivity of 100.0%, specificity of 94.7%, and an accuracy of 95.5% (Z=8.500, P<0.0001); Emax in m/s with the cut-off 5.9m/s showed a sensitivity of 100.0%, specificity of 89.5% and an accuracy of 90.9% for the prediction of malignant CBTs (Z=9.143, P<0.0001).ConclusionsQuantitative analysis of SWE obtained the good performance in the elasticity assessment of CBTs

A study on use of miniature dielectric compound parabolic concentrator (dCPC) for daylighting control application

Low-concentration solid dielectric compound parabolic concentrator (dCPC) and its variations have been widely regarded as an attractive solution to reduce the cost of a photovoltaic (PV) system, particularly for building-integrated application. Different from a mirror CPC, a dCPC allows the light beyond its acceptance angle to penetrate through its lateral surface. This escaped light could be actually used for daylighting, so the dCPC offers a potential for combined PV and daylighting application suitable for the atrium buildings or large green houses. In the modern buildings, an advanced daylighting system such as prismatic panels is used to balance between harvesting daylight and preventing excessive solar heat gain. In contrast, this study aims to evaluate the advantage of the miniature solid dCPC over common prismatic structures according to their daylight transmittance values under both standard and real sky conditions. A commercial optical analysis software PHOTOPIA is firstly used to compare the daylighting control performance between a dCPC rod and two common prismatic elements. The effect of solar altitude and azimuth angles changing with time is considered. A preliminary test under a solar simulator and a real sky condition is also introduced to provide experimental evidence regarding the advantageous feature of a dCPC rod for daylighting control

Performance analysis and design implementation of a novel polymer hollow fiber liquid desiccant dehumidifier with aqueous potassium formate

A novel cross-flow liquid desiccant polymer hollow fiber dehumidifier (PHFD) is investigated numerically in this paper. The main objective of this research is to simulate, and validate the numerical model for future design implementations. The experimentally verified simulation data will be used to develop a set of design and implementation tables and charts as the guidance for selecting the number of fibres and the solution-to-air mass flow ratio of the PHDF under given conditions. A numerical model is developed to simulate the performance of the proposed innovative dehumidifier. This model is validated against three sets of data, i.e. the experimental obtained testing results, analytical correlations and the modelling results from the literature. The influence of various operating conditions such as inlet air properties (i.e. velocity, relative humidity) and inlet solution properties (i.e. temperature, concentration, mass flow rate) on the dehumidification sensible, latent, and total effectiveness, moisture removal rate are numerically analyzed. Dimensionless parameters including the number of heat transfer unit (NTU) and the number of mass transfer unit (NTUm), the solution to air mass flow rate ratio (m*), and the air to solution specific humidity ratio () have been used to evaluate the system performance. The results show that the increase in NTU and NTUm lead to a substantial change in dehumidification effectiveness. When the NTU increases from 0.47 to 7, the sensible effectiveness rises from 0.35 to 0.95. Increasing is another good option for increasing the amount of the absorbed moisture without influencing the latent effectiveness. For an increase of from 1.4 to 2.2, the air inlet and outlet specific humidity difference varies in the range of 0.008 kg/kg and 0.018 kg/kg

The mass transfer coefficient assessment and productivity enhancement of a vertical tubular solar brackish water still

This paper presents an experimental investigation of a single-effect vertical tubular solar brackish water desalination device, with an aim to determine the mass transfer coefficient and its enhancement. The device consists of two closely spaced concentric pipes. The outside of the inner pipe is covered with a wicking material and wetted with hot brackish water. The water vapor evaporated from the wicking material condenses on the inside of the outer pipe. The measured productivity and temperatures at various points are given for different wicking materials thickness, water flow rates and chamber pressure under the condition of given heating power. Mass transfer coefficients are calculated from the experimental results and then applied in the prediction of water productivity. The maximum discrepancy between the calculation yield and measurement yield is relatively small compared with previous study. In addition, it was found that the yield of the solar still is 23.9% higher when the chamber pressure is lower by 25 kPa due to the enhanced mass transfer. Similar, doubling the ambient air velocity can increase the water yield by about 17.0%

A novel solar multifunctional PV/T/D system for green building roofs

A novel transparent roof which is made of solid CPC (Compound Parabolic Concentrator) PV/T/D (Photovoltaic/Thermal/Day lighting) system is presented. It combines the solar PV/T/D system with green building design. The PV/T/D system can achieve excellent light control at noon and adjust the thermal environment in the building, such that high efficiency utilization of solar energy could be achieved in modern architecture. This kind of roof can increase the visual comfort for building occupants; it can also avoid the building interior from overheating and dazzling at noon which is caused by direct sunlight through transparent roof. Optical simulation software is used to track the light path in different incidence angles. CFD (Computational Fluid Dynamics) simulation and steady state experiment have been taken to investigate the thermal characteristic of PV/T/D device. Finally, the PV/T/D experimental system was built; and the PV efficiency, light transmittance and air heating power of the system are tested under real sky conditions

Identification of potential drug targets for varicose veins: a Mendelian randomization analysis

IntroductionVaricose veins are a common chronic disease that creates a significant economic burden on the healthcare system. Current treatment options, including pharmacological treatments, are not always effective, and there is a need for more targeted therapies. A Mendelian randomization (MR) method uses genetic variants as instrumental variables to estimate the causal effect of an exposure on an outcome, and it has been successful in identifying therapeutic targets in other diseases. However, few studies have used MR to explore potential protein drug targets for varicose veins.MethodsTo identify potential drug targets for varicose veins of lower extremities, we undertook a comprehensive screen of plasma protein with a two-sample MR method. We used recently reported cis-variants as genetic instruments of 2,004 plasma proteins, then applied MR to a recent meta-analysis of genome-wide association study on varicose veins (22,037 cases and 437,665 controls). Furthermore, pleiotropy detection, reverse causality testing, colocalization analysis, and external replication were utilized to strengthen the causal effects of prioritized proteins. Phenome-wide MR (PheW-MR) of the prioritized proteins for the risk of 525 diseases was conducted to screen potential side effects.ResultsWe identified eight plasma proteins that are significantly associated with the risk of varicose veins after Bonferroni correction (P < 2.495 × 10−5), with five being protective (LUM, POSTN, RPN1, RSPO3, and VAT1) and three harmful (COLEC11, IRF3, and SARS2). Most identified proteins showed no pleiotropic effects except for COLLEC11. Bidirectional MR and MR Steiger testing excluded reverse causal relationship between varicose veins and prioritized proteins. The colocalization analysis indicated that COLEC11, IRF3, LUM, POSTN, RSPO3, and SARS2 shared the same causal variant with varicose veins. Finally, seven identified proteins replicated with alternative instruments except for VAT1. Furthermore, PheW-MR revealed that only IRF3 had potential harmful adverse side effects.ConclusionsWe identified eight potential causal proteins for varicose veins with MR. A comprehensive analysis indicated that IRF3, LUM, POSTN, RSPO3, and SARS2 might be potential drug targets for varicose veins