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The purpose of this study is to investigate the entire evolution process of shales with various total organic contents (TOC) in order to build models for quantitative evaluation of oil and gas yields and establish methods for assessing recoverable oil and gas resources from in-situ conversion of organic matters in shale. Thermal simulation experiments under in-situ conversion conditions were conducted on Chang 73 shales from the Ordos Basin in a semi-open system with large capacity. The results showed that TOC and Ro were the key factors affecting the in-situ transformation potential of shale. The remaining oil and gas yields increased linearly with TOC but inconsistently with Ro. Ro ranged 0.75%–1.25% and 1.05%–2.3%, respectively, corresponding to the main oil generation stage and gas generation stage of shale in-situ transformation. Thus a model to evaluate the remaining oil/gas yield with TOC and Ro was obtained. The TOC of shale suitable for in-situ conversion should be greater than 6%, whereas its Ro should be less than 1.0%. Shales with 0.75% (Ro) could obtain the best economic benefit. The results provided a theoretical basis and evaluation methodology for predicting the hydrocarbon resources from in-situ conversion of shale and for the identification of the optimum “sweet spots”. The assessment of the Chang 73 shale in the Ordos Basin indicated that the recoverable oil and gas resources from in-situ conversion of organic matters in shale are substantial, with oil and gas resources reaching approximately 450×108 t and 30×1012 m3, respectively, from an area of 4.27×104 km2.

On one hand, large-scale ranking and selection (R&S) problems require a large amount of computation. On the other hand, parallel computing environments that provide a large capacity for computation are becoming prevalent today, and they are accessible by ordinary users. Therefore, solving large-scale R&S problems in parallel computing environments has emerged as an important research topic in recent years. However, directly implementing traditional stagewise procedures and fully sequential procedures in parallel computing environments may encounter problems because either the procedures require too many simulation observations or the procedures’ selection structures induce too many comparisons and too frequent communications among the processors. In this paper, inspired by the knockout-tournament arrangement of tennis Grand Slam tournaments, we develop new R&S procedures to solve large-scale problems in parallel computing environments. We show that no matter whether the variances of the alternatives are known or not, our procedures can theoretically achieve the lowest growth rate on the expected total sample size with respect to the number of alternatives and thus, are optimal in rate. Moreover, common random numbers can be easily adopted in our procedures to further reduce the total sample size. Meanwhile, the comparison time in our procedures is negligible compared with the simulation time, and our procedures barely request for communications among the processors.

Aiming at solving the problems of bad imperceptibility and low embedding rate of existing algorithms, a novel large-capacity reversible image watermarking based on improved difference expansion (DE) is proposed. Firstly, the smoothness calculation algorithm is used to calculate and sort the smoothness values of the divided image sub-blocks; then, the scrambled watermark is embedded into the sub-blocks with less smoothness after removing the abrupt point by using the generalized difference expansion (GDE); finally, the absolute difference operation is applied to the generated overflow pixels to make their pixel values within a reasonable range for embedding watermark information. Under the premise of ensuring a certain visual quality, multiple watermark embedding can effectively improve the embedding rate. The simulation results show that this algorithm not only realizes blind extraction, but also recovers the original images without loss. At the same time, this algorithm achieves a high embedding rate (the average embedding rate is as high as 77.91 dB) without decreasing the visual quality.

Posso Village is one of the villages located in Kwandang District, through a village-owned enterprise formed a successful IKM together that produces traditional coconut oil. The purpose of this service activity is to improve the quality of traditional coconut oil and its waste and the management of partner businesses. The results of this service activity obtained several machines such as a coconut peeler machine with an average coconut peeling of about 18 s/piece at a machine speed of 2000 rpm and a shaft 25 rpm, a large capacity coconut milk squeezer machine with manual operation via hydraulic power, a VCO mixer machine with a capacity of 20 liters with a rotational speed of 900 rpm to 4200 rpm, an ethanol distillation machine with a capacity of 30 liters equipped with a condenser, a drum for burning shells into charcoal, product packaging and label designs, online trading accounts and operations have been obtained by partners.

One of the leading places among grain and fodder crops is maize. About 3,500 types of products are produced from it. This crop is of great importance as a high-energy food for all species of animals and birds. In the process of corn grain production, the most labor-intensive is harvesting - 60 ... 80% of the total labor costs. In the latter, the most labor-intensive stage of corn harvesting is the threshing of the cobs, the quality of which is characterized by two main indicators - injury to the grain and under-threshing of the cobs. At the moment, a large number of threshers have been developed, different in principles and threshing technological schemes. The existing threshers have a large capacity and are designed to thresh large volumes of corn cobs. However, in the structure of maize cultivation, a significant place is occupied by small crops in the private sector. After the corn cobs are harvested, they are threshed by hand or a variety of hand and mechanical threshers are made. In addition, at the present time, when the physical nature of the process of threshing corn with threshers has not yet been sufficiently studied and their theory has not been sufficiently developed, the distribution of threshers according to the principle of threshing by blow or grinding is not complete. In this regard, the article substantiates a constructive and technological scheme of a small-sized thresher, which provides threshing of corn cobs in a wrapper with minimal injury to the grains. As a result of theoretical studies, rational values ​​of the design and technological parameters of the developed threshing device have been established: moisture content of the cobs 12 ... 22%; threshing drum rotation frequency 300 ... 400 min-1; the height of the teeth is 12 ... 18 mm; tooth pitch 3 ... 8 mm ..

Objective. To determine the most relevant way to improve the energy efficiency of the system for discharging liquefied natural gas (LNG) from large-capacity storage facilities. Methods. The method of analysis of existing systems for LNG discharge from storage tanks was used to identify critical (emergency) elements of the system to be improved and possible options of improving structural elements. Results. The operation of the system for discharging LNG from storage tanks was analysed and its main characteristics were described. Main problems associated with designing and building borehole pumps, as well as goals and tasks of designing new borehole pump structures were studied. The main types of LNG borehole pumps, their varieties, and types of drives were studied to choose the most optimal new option of improving pumps for systems for discharging LNG from storage tanks. Further, it will be necessary to calculate geometric parameters of the hydroturbine and operation modes of its wheel being in connection with the centrifugal pump wheel. Conclusion. Experience of using storage facilities shows that LNG pumps are the most critical units significantly increasing production risks. Therefore, the LNG borehole pump design improvement was chosen as a method to increase the energy efficiency of the system for discharging LNG from large-capacity storage facilities. Based on the considered advantages and disadvantages of structural elements of the existing LNG borehole pump design, we chose the replacement of the electric pump drive with an alternative one as the most optimal improvement method.

The aim of planning the construction of the Grand Mosque of Universitas Samudera Aceh (UNSAM) was to help Universitas Samudra in Langsa city so that the construction of a new mosque in the campus environment has a large capacity with self-managed construction. The methods used for the study were literature design, site survey, interior spatial analysis, design planning. The findings and implications of a well design and planning is that it is hoped the mosque becomes the pride of the campus residents in particular and the people of Langsa city in general. It is also hoped to be able to support religious activities and worship for all academicians of Universitas Samudera.

High-temperature superconducting (HTS) DC cables with the merits of light weight, large capacity and low loss provide a novel power transmission method for future utility grid. In this paper, the electromagnetic characteristics of unipolar and bipolar coaxial HTS DC cables are compared by finite element simulation. Besides, the 3D magnetic flux density distribution characteristics of HTS DC cable are obtained. The method to investigate the influence of winding angle on HTS DC cable magnetic flux density is also applied to 3D HTS DC analysis.

Changes in food distribution have led to the fact that sales of products by commercial enterprises take place in a large area by small batches fulfilling individual orders. In most cases, the delivery of products to commercial enterprises is made by road. However, there are virtually no guidelines for the choice of vehicles, their configuration and quantity necessary for groupage. Therefore, it is essential to determine road transportation efficiency, which on delivery routes is characterized by the transportation costs of 1 ton of freight only. The lack of publicly available statistical indicators of automobile operational parameters significantly complicates transportation costing. At the same time, solving such tasks of planning groupage shipments as the choice of a car, its route, fleet composition, etc. requires awareness of interdependences between transportation costs and the capacity of a car. It is proposed to determine transportation costs based on a vehicle capacity by extrapolating the vehicle parameters according to the manufacturer and service companies` data, as well as an algorithm for delivery route operation modeling. Through the example of Isuzu refrigerated vehicles, the study shows that the replacement of one ride of a car with a large capacity by two rides performed by cars with a lower capacity according to the transportation cost reduction criterion is impractical. A comparison of the costs for Isuzu vehicles with similar capacity shows that there are no points of equivalent transportation costs. That is, the replacement with a larger-capacity car becomes cost-effective after the complete consignment of a lower-capacity vehicle

Задачі підсуNowadays with the rapid development of information technologies, UAV-based Remote Sensing (drone remote sensing) gives a new opportunities for conducting scientific research in a much more detail way. UAVs (unmanned aerial vehicles) give the opportunity to acquire data at sufficiently low cost. They also provide remote data more rapidly than piloted aerial vehicles. Nowadays drones are often used, because application of piloted aerial vehicles can be dangerous, difficult and expensive for some territories. Application of low altitude UAVs give a possibility to achieve images with a very high resolution and sufficient precision. In this article structure and main details of drones were considered. It also was noted, that technologies of UAV-based Remote Sensing are used in different areas.Agricultural drones help to analyze crops, make decisions on how to use the crop information and take the necessary actions to correct the problems. These unmanned aerial vehicles let to see fields from the sky. Agricultural drones are used to help increase crop production and monitor crop growth. Drones and sensors give a detail picture of fields. They can survey the fields periodically. Agricultural drones can reveal many issues such as soil variation, pest infestations and changes in the crops over time. They also show differences between healthy and unhealthy plants. Drones are flied over the crops and help to make decisions on how to proceed given the crop information. Nowadays there is a large capacity for growth in the area of agricultural unmanned aerial vehicles. With technology constantly improving, imaging of the crops will need to improve as well.Drones are used for exploring for minerals and mapping deposit sites, they are used in the oil and gas industry for remote monitoring. Drones can provide information of nature disasters and give help to assess property damage. They help to conduct forest monitoring and to assess plant health. Unmanned aerial vehicles are also used in a military capacity and ecological monitoring. It also was noted, that there is a large capacity for development and improvement of unmanned aerial vehicles.путникового моніторингу в аерокосмічному комплексі

This work presents an assessment of the applicability of existing benchmark critical experiments to the criticality safety code validation for a large-capacity high-assay low-enriched uranium (HALE...

Background: The COVID-19-pandemic poses challenges to the medical system and especially to endoscopic staff and patients. National, European and International societies provided recommendations on how to safely perform endoscopic procedures during the current pandemic. Until now, the effect of the current pandemic on tertiary endoscopy centers has not been reported. Objective: The aim of this was to analyze the influence of the early SARS-CoV2-pandemic on endoscopic care and work flow in 2 European tertiary endoscopy units. Methods: Data from 2 tertiary endoscopy units (Katowice and Munich) were retrospectively collected during the early pandemic and compared to an equivalent pre-pandemic period. Data include procedures, complications, benchmarks, and influence on endoscopy training. Results: During the early pandemic, we noted a highly significant decrease (49.1%) in the overall number of all endoscopies with a significant increase in therapeutic procedures. Besides, there were no significant differences in the number of urgent endoscopic retrograde cholangiopancreatography or interventional endoscopic ultrasound procedures. The exceptional situation reduced endoscopic procedures performed by trainees significantly. Conclusions: The SARS-CoV2-pandemic halved the endoscopy service of 2 tertiary centers while maintaining an urgent therapeutic service. Recommended personal safety measures in endoscopy proved to be efficient and safe in preventing SARS-CoV2 infection of staff or spreading. Unnecessarily, the SARS-CoV2 pandemic prevented routine endoscopy training.

Based on our previously published reports concerning the response of quiescent (Q) tumor cell populations to boron neutron capture therapy (BNCT), the heterogeneous microdistribution of 10B in tumors, which is influenced by the tumor microenvironment and the characteristics of the 10B delivery carriers, has been shown to limit the therapeutic effect of BNCT on local tumors. It was also clarified that the characteristics of 10B-carriers for BNCT and the type of combined treatment in BNCT can also affect the potential for distant lung metastases from treated local tumors. We reviewed the findings concerning the response of Q tumor cell populations to BNCT, mainly focusing on reports we have published so far, and we identified the mode of BNCT that currently offers the best therapeutic gain from the viewpoint of both controlling local tumor and suppressing the potential for distant lung metastasis. In addition, based on the finding that oxygenated Q tumor cells showed a large capacity to recover from DNA damage after cancer therapy, the interrelationship among the characteristics in Q tumor cell populations, tumor heterogeneity and cancer stemness was also discussed.

This paper studies an intermediated market for a homogeneous good with middlemen who hold inventories of the good. Using a directed search approach, I investigate a steady state equilibrium. Under market frictions and competition, the ask price of middlemen includes a retail premium for the immediacy service to buyers and the bid price includes a wholesale premium charged to sellers for guaranteed sale. It is shown that the middlemen enhance the economy-wide eciency, and that the bid-ask spread can be non-monotone in the middlemen’s inventory capacity. The simple model provided here has wide applicability and oers economic insights into many empirically relevant forms of middlemen, especially in the context of financial intermediaries, international trade and retail stores.

Abstract Environmental concerns such as climate change due to rapid population growth are becoming increasingly serious and require amelioration. One solution is to create large capacity batteries that can be applied in electricity-based applications to lessen dependence on petroleum. Here, aluminum–air batteries are considered to be promising for next-generation energy storage applications due to a high theoretical energy density of 8.1 kWh kg−1 that is significantly larger than that of the current lithium-ion batteries. Based on this, this review will present the fundamentals and challenges involved in the fabrication of aluminum–air batteries in terms of individual components, including aluminum anodes, electrolytes and air cathodes. In addition, this review will discuss the possibility of creating rechargeable aluminum–air batteries. Graphic Abstract

Large capacity hydrogenerators are operated at overloads during the period of excess water flow in the river or frequency support to the grid at peak hours. The extensive conditions may extend to six weeks with 20% overload for a typical hydropower plant located in the northern region of India. High-power, low-speed, direct-driven hydroturbine synchronous generators (HTSGs) are having resistance in rising temperature and self-cooling techniques to withstand the multiple loading points. This article presents a 250-MW CB 870/300-28 HTSG machine modeling along with electromagnetic design and simulations through a three-dimensional finite-element analysis software. The temperature distribution of the machine, operates at 10% and 20% continuous overloads, are explored via a coupled thermal and fluid-dynamical analysis. The simulated thermal results at continuous overloads are presented and are validated with a case plant's test report. A parallel study when the load goes unbalanced at overloads is done through simulation and a prototype validation of a 2.2-kW machine is substantiated in addition. The strength and flexibility of the operation of this machine assist the generalized results to operate at 20% overload continuously with the utility of thermal distribution.

Electricity cannot be cost-effectively stored even for short periods of time. Consequently, wholesale electricity prices vary widely across hours of the day with peak prices frequently exceeding off-peak prices by a factor of ten or more. Most analyses of energy-efficiency policies ignore this variation, focusing on total energy savings without regard to when those savings occur. In this paper we demonstrate the importance of this distinction using novel evidence from a rebate program for air conditioners in Southern California. We estimate electricity savings using hourly smart-meter data and show that savings tend to occur during hours when the value of electricity is high. This significantly increases the overall value of the program, especially once we account for the large capacity payments received by generators to guarantee their availability in high-demand hours. We then compare this estimated savings profile with engineering-based estimates for this program as well as a variety of alternative energy-efficiency investments. The results illustrate a surprisingly large amount of variation in economic value across investments.

Sodium layered transition metal oxides have been considered as promising cathode materials for sodium ion batteries due to their large capacity and high operating voltage. However, mechanism invest...

PT PLN (PERSERO) is a company engaged in electricity in Indonesia and plays a role in the generation and distribution of electricity to consumers. PLN has quality standards that must be met, one of which is a stable frequency even though the load keeps changing all the time. In electric power systems, the frequency value is an indicator of the balance between active power generated with a total load of active system power and losses. The frequency value will increase if there is an excess generation and conversely the frequency value will decrease if there is a shortage of generation or overload. If there is a disturbance that causes the large capacity generating unit to be release from the systems (trip), in this case the PLTU Pangkalan Susu and PLTU Nagan Raya will cause a decrease in frequency so that the Northern Sumatera interconnection system is disrupted. A large decrease in frequency can lead to failure of generating units in a row so that it can cause total system failure (blackout). To avoid a total system failure (blackout) a load shedding scheme with under frequency relay (UFR) is carried out. This research is done by experimental methods. According to this research, it’s been found that the setting of under frequency relay conducted by PLN UP2B Northern Sumatera is good, in this sense of blocking the system from blackout due to a massive power trip.

The initial conditions indicate that the cognitive abilities of early childhood are still low in understanding the workings of cow milking. In the activity of milking cow's milk, children's cognitive abilities are needed so that the results obtained can be maximized. Based on observations on February 4, 2019, researchers found that many early childhood children are afraid of milking cows, there are also students who do not understand how to milk cows to obtain milk with large capacity. Therefore, the researchers used the artificial cow model artificial media. This model is a three-dimensional imitation model with a length of 120cm x 75cm. this model is used so that students can listen to the process of milking the cow properly, so that students can practice directly properly and correctly. The subject and location of this study were group B RA Nurul Islam, Boro Village RT 01 / RW 01, Tanggulangin Subdistrict, Sidoarjo Regency with subjects as many as 14 PAUD students consisting of 10 male students and 4 female students. This type of research is classroom action research (PTK) carried out in two cycles, data collection techniques used are teacher observation sheet instruments, student observation sheets and practice test sheets milking cows with three-dimensional imitation dairy media media. The results showed an increase in children's cognitive abilities in the practice of milking cows with a three-dimensional imitation model of dairy cows reaching a developmental percentage of 64.28%, and increasing in the second cycle of 92.8%. Then the results of observation of teacher activities in the first cycle were 65.5% which increased by 22% to 87.5% in cycle II. While observations of student activities obtained results of 64.28% results in the first cycle, and 85.7% results in the second cycle. Each aspect of a child's cognitive abilities in understanding how to milk a cow with increased dairy cow media in the second cycle has achieved a predetermined indicator of success so it does not need to be increased in the next cycle. Based on the results of the research described above, it can be concluded that the medium of dairy cows can improve children's cognitive abilities in understanding and practicing milking with dairy cow three-dimensional model media in group B RA Nurul Islam Boro Village RT 01 / RW 01 Tanggulangin District Sidoarjo.

A comprehension of the dielectric strength recovery processes during the interruption of short-circuit currents in the high-voltage SF6 gas-blast circuit breakers is necessary for their modernisation in order to increase the rated voltage and short circuit breaking current per one break. This paper presents numerical results of the turbulence effects on the interruption ability in the SF6 extinguishing arc chamber.

Introduction. The purpose of the study is to formulate and analyze problems that should be solved before implementing the ideas of fire fighting in high-rise buildings by using unmanned aircraft systems (UAS). To achieve this purpose, the following concepts were considered and assessed: the possibilities of water and water-based fireextinguishing solutions delivery to the fire source from a ground pumping station using a hose line; delivering compression foam along a vertically positioned hose line; and, the possibilities of UAS for fire extinguishing; supply of fire extinguishing powders and aerosols placed on the UAS to the center of fire. Methods. The adopted in Russia hydraulic calculation methods, the results of the experimental studies on the compression foam, the existing theoretical and practical advances in the field of fire-extinguishing by jet delivering fire-extinguishing substances. Conclusions. The results achieved show that one of the ways to increase fire extinguishing capability in high-rise buildings can be provided by applying UAS for continuous horizontal supply of water based solution or compression foam to the center of fire, as well as supply of fire extinguishing powders and aerosols using powder fire barrels and pyrotechnic cartridges. However, to implement each of these methods, certain problems need to be solved. They are: the fire extinguishing height limitations a large capacity of UAS needed; a hydraulic calculation methodology for compression foam supply systems; safe use of UAS under the conditions of compression foam separation; the possibilities for developing supply equipment, which can be utilized by the UAS.

Urodele amphibians such as the axolotl (Ambystoma mexicanum) display a large capacity for tissue regeneration and remarkable resistance to cancer. As a model organism, axolotl thus offers ...

In-memory computing has inspired researchers to consider integrating large-capacity persistent memory (PM) into the main memory subsystem. However, several challenges still remain for providing an integration approach for DRAM-comparable PM on existing enterprise servers. Current commercial servers tend to feature multiple sockets with shared-memory NUMA organizations. Simply constructing a hybrid main memory architecture for these NUMA organizations requires considerable modifications of the system software. Another significant problem in these designs is the high latency of accessing PM on a remote socket, which results in performance degradation. To address these problems, we integrated PM as a memory-based model and as a storage-based model simultaneously on one commercial server, which offers a short-cut approach for enterprises to build commercial NUMA machines with large-capacity PM. In the memory-based model, rather than focusing on the persistence attribute, we propose an architecture that benefits managing the integrated PM and DRAM space in a unified manner and that facilitates bypassing vast modifications to the system software. We also present an adaptive mechanism that can automatically introduce a moderate amount of PM into the local socket to hinder access of a remote socket by the degree of memory pressure. In the storage-based model, under the condition of taking full advantage of the PM's persistence, we abstract a PM volume device and overcome the torn sector problem. To demonstrate the effectiveness of the proposed scheme, we design and implement Dapper, an adaptive persistent memory manager prototype. The experimental results show that, compared to typical memory management approaches, Dapper achieves performance improvements of 13.1 percent to 34.0 percent on average on Graph500 BFS_SSSP benchmarks and SPEC CPU2006 floating point workloads, respectively. Moreover, when deploying F2FS on our PM volume, we find that Dapper outperforms existing methods by 5.8 percent on tar and by 11.9 percent on untar.

Li-S batteries are a promising next-generation battery technology but are confronted with a series of fundamental challenges, in particular the notorious shuttle effect of soluble polysulfide intermediates. Current research efforts are mostly focused on designing proper host materials for the entrapment and immobilization of polysulfides. Herein, we demonstrate that electrocatalysis may play an unexpected role in Li-S batteries. Nanosized tungsten carbide particles dispersed on the carbonaceous support are prepared from the pyrolysis of phosphotungstic acid-functionalized metal-organic frameworks. Both experimental measurements and theoretical calculations demonstrate that they not only have strong affinity toward polysulfide intermediates, but also significantly accelerate the reduction of low-order polysulfides that is otherwise kinetically challenged. Using these supported tungsten carbide nanoparticles as the cathode catalyst, our Li-S batteries achieve large capacity, excellent cycling stability and impressive rate capability.

The cost of energy use in buildings around the world is gradually increasing. To achieve energy saving in buildings, among the Thermal Energy Storage (TES) systems available, the use of Latent Heat Storage (LHS) is being actively studied. To effectively use an LHS system, Phase Change Materials (PCMs) are applied to buildings, and thus Shape-Stabilization PCMs (SSPCMs) must also be used. In this study, SSPCMs were manufactured using a large-capacity vacuum impregnation machine, and consisted of Exfoliated graphite nanoplatelets (xGnP) and n-octadecane. The SSPCMs were divided according to size (A, B, C, and D). SSPCMs were applied to a gypsum board (GB). Through a compressive strength test, a weight of 5% was applied to GB_A5, and the strength was reduced by 23.1% compared to GB and 50.1% for GB_A10. The thermal properties were analyzed based on a dynamic thermo-graphic analysis and dynamic heat flow analysis. From both analyses, it was confirmed that the GB with SSPCM showed a sufficient latent heat range and a corresponding exothermic range, compared to the reference GB. Based on EnergyPlus 8.5., a cooling energy reduction of approximately 3.4% was achieved through the addition of 10% SSPCMs to GB under the operating conditions. Therefore, it was proven that the application of SSPCMs to building materials is reasonable for achieving energy saving in buildings.

In this study, Li(Ni1/3Mn1/3Co1/3)O2 (NMC333) and Li(Ni0.5Mn0.3Co0.2)O2 (NMC532) have been subjected to a phosphoric acid (H3PO4) solution treatment to form a thin Li3PO4 coating on their surfaces. The Li3PO4 coating formed is found to be very potent in enhancing the specific capacity of the first discharge as well as the rate capability and capacity retention in the subsequent charge/discharge cycles for both NMC333 and NMC532. The specific capacity of the first discharge for NMC532 has been increased drastically from ∼160 mA h g−1 for pristine NMC532 to ∼250 mA h g−1 for Li3PO4-coated counterpart at 0.1C and such a large capacity enhancement is retained throughout the subsequent cycles at 1C. The final specific capacity of Li3PO4-coated NMC532 is 187 mA h g−1 after 100 cycles at 1C, whereas the corresponding value of pristine NMC532 is only 50 mA h g−1. The rate capability has also been improved significantly with Li3PO4-coated NMC532 exhibiting ∼150 mA h g−1 capacity at 6C while pristine NMC532 showing zero capacity. Similar improvements have also been achieved with NMC333. These results demonstrate that the H3PO4 treatment is a facile and general method to improve the electrochemical properties of NMCs with different compositions and can be utilized for practical applications.

In previous data hiding techniques, binary rules are usually used to guide the fine-tuning of the values of basic objects in the host media to hide bit 0 and bit 1. In this paper, we propose a new data hiding technique for gray images based on querying a 256x256 information table. The information table is constructed by cloning a 3x3 basic block, which we call seed block. Eight unsigned integer values between 0 and 7, i.e., 3 bit binary data, are assigned to different elements of the seed block. Each time, a pair of pixels are chosen from a host image, and their pixel values are used as row and column numbers to look up the information table. If element value obtained by looking up the table is equal to the 3 bit binary data to be hidden, the values of the pixel pair will remain unchanged. Otherwise, take this element as the central point, we call it the focus element, to enclose a 3x3 window in the information table. Then in the window, find the element which is equal to the data to be hidden. Finally, update the pixel values of the pair with the row and column numbers of the found element in the window. Since the row and column numbers are in the range of 0-255, the updated pixel values will not overflow. In the proposed algorithm, a pair of pixels can hide 3 bits of information, so the embedding capacity is very high. Since the adjustment of pixel values is constrained in a 3x3 window, the modification amount of pixel values is small. The proposed technique belongs to fragile digital watermarking, so it can be used for image authentication and tamper localization. By the evaluation of data hiding capacity, security, imperceptibility, computational cost and extensibility, this algorithm is superior to existing information hiding techniques. The proposed technique can also be used in color image and audio data hiding.

Saliva as a sample matrix has been an attractive alternative for the detection of SARS-CoV-2. However, due to potential variability in collection and processing steps, evaluating a proposed workflow amongst the local population is recommended. Here, we aim to validate the collection and treatment of human saliva as a direct specimen for RT-qPCR-based detection of SARS-CoV-2 in Indonesia. We demonstrated that SARS-CoV-2 target genes were detected in saliva specimens and remained stable for five days refrigerated or room temperature storage. The method of processing saliva specimens described in this report bypasses the need for an RNA-extraction process, thereby reducing the cost, time, and manpower required for processing samples. The developed method was tested across nine commercial kits, including the benchmark, to demonstrate its wide applicability on multiple existing workflows. Our developed method achieved 86% overall agreement rate compared to paired nasopharyngeal and oropharyngeal swab specimens (NPOP). With the assistance of a saliva sampling device, the collection was found to be more convenient for individuals and improved the overall agreement rate to 97%.

Despite the continuous downscaling of complementary metal–oxide–semiconductor (CMOS) devices, various scenarios of technology have also been proposed toward the shrinking of semiconductor memory. In this paper, a high-density memory (HDM) has been proposed on the basis of band-to-band tunneling (BTBT) for low-power, high density, and high-speed memory applications. The geometric structure and electrical properties have been demonstrated by using TCAD tools. Typical memory operations including read, program, and erase have been designed and performed. High operation speed, lower power consumption, as well as good reliability characteristics have been achieved by simulation, which indicates that the HDM may have potential application value as a novel semiconductor memory device.

In open-plan office rooms, one of the main reasons for the nuisance of work is the noise from employees' conversations. In order to limit it, the permissible values of the parameters characterizing the acoustic properties in those rooms on a 2-level scale are defined.The article introduces a 3-level scale for assessing the acoustic properties (bad, fair, good) of a room based on EN ISO 3382‑3:2012 and PN-B-02151-4:2015 - criterion 1. Additionally and alternatively, a new 3-level scale assessment criterion (criterion 2), concerning acoustic separation between groups of workstations, was determined. In order to meet that criterion, it is necessary to take into account the acoustic treatment of the room. A multivariate (7) acoustic treatment studies were performed using computational simulation methods.Requirements, according to PN-B-02151-4:2015, were met after the application of a sound-absorbing suspended ceiling and acoustic screens at workplaces. To meet the requirements of EN ISO 3382‑3:2012, it was necessary to additionally use sound-absorbing materials on the walls and acoustic screens separating the naves of the room. To meet the requirements of criterion 2, it was necessary to additionally use acoustic screens separating groups of workstations and acoustic screens in passages.Appropriate acoustic properties can be obtained in open space offices. Appropriate acoustic properties can be obtained in open-space offices. The requirements according to PN-B-02151-4:2015 can be met with much lower acoustic treatment than the requirements according to EN ISO 3382‑3:2012. The use of a 3-level scale for assessing the acoustic properties of a room allows for the differentiation of rooms with regard to their acoustic properties. The introduction of a new assessment method, taking into account the grouping of workplaces in a room, makes it possible to assess the acoustic properties of a room in a more reliable way, by neglecting the impact on the assessment of areas where people are not present. Med Pr. 2021;72(4):375-90.W biurowych pomieszczeniach open space jedną z podstawowych przyczyn uciążliwości pracy jest hałas rozmów pracowników. W celu jego ograniczenia określono dopuszczalne wartości wielkości charakteryzujących właściwości akustyczne w tych pomieszczeniach w skali dwustopniowej.W artykule wprowadzono trzystopniową skalę oceny właściwości akustycznych pomieszczenia (złe, słabe, dobre) bazującą na wielkościach oceny według PN-B-02151-4:2015 oraz PN-EN ISO 3382‑3:2012 – kryterium I. Określono dodatkowo nowe, także trzystopniowe, II kryterium oceny dotyczące separacji akustycznej między grupami stanowisk pracy. W celu jego spełnienia konieczne jest uwzględnienie adaptacji akustycznej pomieszczenia. Podano wyniki badania metodami symulacji obliczeniowej wielowariantowej (7) adaptacji akustycznej w pomieszczeniu trzynawowym.Wymagania PN-B-02151-4:2015 (kryterium I) zostały spełnione po zastosowaniu: dźwiękochłonnego sufitu podwieszanego i ekranów akustycznych przy stanowiskach pracy. Do spełnienia wymagań PN-EN ISO 3382-3:2012 (kryterium I) konieczne było dodatkowe uwzględnienie materiałów dźwiękochłonnych na wewnętrznych ścianach pomieszczenia oraz ekranów akustycznych rozdzielających nawy pomieszczenia. Do spełnienia wymagań kryterium II konieczne okazało się dodatkowe zastosowanie ekranów akustycznych rozdzielających grupy stanowisk pracy oraz ekranów akustycznych w ciągach komunikacyjnych dla pieszych.Jest możliwe uzyskanie odpowiednich właściwości akustycznych w pomieszczeniach biurowych open space. Wymagania określone zgodnie z PN-B-02151-4:2015 można spełnić przy znacznie mniejszej adaptacji akustycznej niż wymagania PN-EN ISO 3382‑3:2012. Zastosowanie trzystopniowej skali oceny właściwości akustycznych pomieszczenia pozwala w bardziej precyzyjny sposób różnicować je pod względem ich właściwości akustycznych. Wprowadzenie nowego sposobu oceny, uwzględniającego grupowanie stanowisk pracy w pomieszczeniu, pozwala w bardziej miarodajny sposób oceniać właściwości akustyczne przez pominięcie wpływu na ocenę obszarów, w których nie przebiega praca. Med. Pr. 2021;72(4):375–390.

The dynamic stability of journal bearings is an important problem for rotating machinery because the dynamic properties of the bearing have a direct influence on machine stability and safety. Because of their simplicity and large capacity, the plain journal bearings are frequently used in rotating machinery; however they can become unstable under small loads and have the tendency to generate a whirl motion with a frequency of about one half the rotational frequency of the shaft. The radius of the whirl orbit can rapidly increase so that the shaft and the sleeve can come into contact, a phenomenon that would damage the bearing. Therefore the study of the dynamic behavior of the journal bearings, especially after the instability occurs, is of theoretical and practical importance. The bearing stability can be improved by adding grooves and holes or by reshaping the bearing surface from perfectly circular to one that incorporates lobes, offsets, tilting pads, etc. The main disadvantage of these methods is that any gain in the bearing stability may reduce the maximum load carrying capacity.