Low Cost Price Research Articles

Printing Parameter Optimization of Biodegradable PLA Stent Strut Thickness by using Response Surface Methodology (RSM)

This work presents printing parameter optimization of 3D printed biodegradable PLA stent. This study is motivated by a gap in current knowledge in 3D printing of stents identified in an extensive literature review. With the demand of coronary artery stents rising every year, the stent production demands a higher quality, lower cost, faster and economical process. Due to its availability relatively low-cost price and adaptability, PLA has been identified for an ideal material for biodegradable stents. Previously, laser micromachining was widely used for processing coronary stent. The emerging of 3D printing process has gained attention for its low cost, high reliability, simple operation and flexibility has shown potential as promising solutions in stents fabrication. The use of 3D printing for stent manufacturing purpose is newly emerge and not widely reported. Up to now, less research has been conducted on 3D printed PLA coronary artery stents. This work therefore, aims to study the relationship of the 3D printing processing parameter towards stents quality. Strut thickness become the key aspects in stents manufacturing. Processing parameter optimization was performed by using Response Surface Methodology (RSM). Nozzle temperature and printing speed were both effecting the strut thickness formations regardless of printing orientations.

저가항공사의 서비스 요인이 재이용 의도 및 가격공정성에 미치는 영향: 사우스웨스트 사례를 중심으로

This research investigates the determinants of low cost carrier reuse intention and price fairness. As the research subject, this research adopts Southwest Airlines because the business is a representative success case as the low cost carrier. This research proposes three elements to account for price fairness, and these are comfort, waiting, and schedule. As antecedents of reuse intention, this research proposes four elements, and these are comfort, waiting, schedule, and price fairness. For the data collection, this research employed Amazon Mechanical Turk. The number of observation for the statistical analysis is 308. This research used statistical tools for the data analysis (e.g., frequency analysis, correlation matrix, descriptive calculation, exploratory factor analysis, reliability test, and multiple regression analysis). The results indicate that price fairness is positively influenced by schedule and comfort. Also, the results showed that reuse intention is positively affected by comfort and schedule. However, reuse intention is negatively influenced by waiting.

European gasoline markets: price transmission asymmetries in mean and variance

ABSTRACT The main objective of this article is to analyse the different sources of asymmetric price transmissions in the fuel market for France, Germany and Spain. During the last decades, the EU has carried out several common energy policies to achieve more efficient and competitive markets. However, given the specific characteristics of each country, the question we want to address is if fuel prices across EU members behave differently in response to different market structures. Oil operators have been targeted by competition authorities for conducting non-competitive practices. To figure out whether the common complaint that gasoline prices adjust differently to positive or negative input price changes, dynamic asymmetric models for the mean and variance are developed for each country. Several asymmetric specifications for the mean and variance are considered. The best specification combines double threshold error correction models (DT-ECM) for the mean with asymmetric EGARCH plus an asymmetric dummy variable for the conditional variance. We show that French gasoline prices behave more competitively, adjusting quicker to the long-run equilibrium and with more price volatility. This outcome is consistent with the strong presence of hypermarkets following low-cost pricing strategies in France.

Green process for adsorptive removal of ethion (O,O,O′,O′-tetraethyl S,S′-methylene bis(phosphorodithioate) from agricultural wastewater using modified surface of orange peel and apricot kernel

Smart absorber with engineered surface, low cost price becomes utmost importance for application in water treatment. Pesticide represents the fatal problem in water contamination due to large quantity misused by the farmers. Ethion is a common contaminated insecticide found in wastewater, so it is really important for removal of ethion from contaminant water. Here, the adsorption characteristics of ethion and its degradation products were studied using modified and functionalized low cost adsorbent. The modified agricultural wastes [orange peels (OP) and the outer crust of apricot kernel (AK)] were characterized and analyzed. Physical and chemical depositions of ethion residues on the surface of absorbers (OP and AK) were utilized.Theoretical calculations/modelling on surfaces of OP and AK were studied using Langmuir and Freundlich isotherm model. The results show that the removal efficiency of ethion increased when the pH of adsorption system increased then decreased at pH greater than 7. The using of different adsorbent doses found that the 95.5 % ethion removal was achieved when 16.5 g/L of the outer crust of apricot kernel. The kinetic model shows that the ethion uptake with the orange peels and apricot kernel adsorbents is a pseudo-second order adsorption.

Green, Natural and Low Cost Xanthum Gum Supported Fe3O4 as a Robust Biopolymer Nanocatalyst for the One-Pot Synthesis of 2-Amino-3-Cyano-4H-Pyran Derivatives

Today, due to expanding the demand for inexpensive catalysts, recyclable magnetic nanocatalysts immobilized on polysaccharides have found more superiorities versus classical heterogeneous catalysts. Xanthan gum is a polysaccharide that contains acidic features and low-cost prices has various applications. Herein, it was demonstrated that xanthan gum can attract more attentions in catalysis science and technology. Therefore, magnetically recoverable Fe3O4@xanthan gum biopolymer nanocatalyst was prepared by in-situ method and used for the synthesis of 2-amino-3-cyano-4H-pyran derivatives via a multicomponent reaction at room temperature in ethanol. The characterization of Fe3O4@xanthan gum biopolymer nanocatalyst was carried out by vibrating sample magnetometer (VSM) curves, energy-dispersive X-ray (EDX) analysis, Fourier transform infrared (FT-IR) spectroscopy, thermogravimetric analysis (TGA), powder X‐ray diffraction (XRD) pattern, field emission scanning electron micrograph (FESEM) image and 1H and 13C nuclear magnetic resonance (NMR) spectra.

Comparison of water use efficiency, profitability and consumer preferences of different rice varieties in Punjab, Pakistan

Due to rapid population growth, water scarcity and food insecurity have become the major problems for Pakistan. Therefore, the efficient utilization of limited resources such as water is very important in agriculture. Paddy or rice—Pakistan’s second most important cereal and staple crop—is a water-intensive crop. The present study aims to estimate the water use efficiency, profitability, and consumer preferences of different paddy varieties such as basmati, coarse and hybrid rice in Punjab. To this end, we collected field survey data from 330 rice growers in six districts of the rice–wheat zone of Punjab. The results showed that basmati rice is more profitable due to low production cost and higher prices. Although the number of irrigations applied to basmati rice and coarse rice was higher than that of hybrid rice, the amount of water applied to hybrid rice was the highest. Therefore, the total irrigation cost of hybrid rice is higher, while the coarse rice has higher water productivity. Furthermore, the economic productivity of water applied to basmati rice and coarse rice is higher than that of hybrid rice. Consumer preferences based on data from 150 consumers indicate that basmati rice is a favorite of consumers and that hybrid rice is the least popular. These results imply that it is better to grow basmati or coarse rice than hybrid rice due to water shortages in Pakistan. Another approach is to replace these varieties with alternative crops such as corn and soybeans that require less water.

Development and implementation of an emission optimization model for passenger flight bookings

In this analysis we discover the potential of a more transparent emission declaration system, in order to a) facilitate for environmentally concerned consumers to choose low-emission flights, and b) provide data for a future emission trading system where the aviation industry is accounted for its emission costs. Some air travel consumers book flights through low-cost flight ticket price comparison websites, that offer comparisons on price, convenience, travel time, and other factors relevant to the consumer. As a basis for this study, an algorithm designed for “flight CO2 emissions comparisons”, was developed and implemented on Sweden’s largest flight ticket price comparison website that compares flights by CO2 emissions in kg per passenger and trip. A visitor to the site can now also select a flight based on the ranking of carbon emission levels from each flight. In addition to the implementation of the algorithm in a commercial aviation booking system, a survey was conducted to analyze consumer preference data to glean insights and make conclusions about flight ticket price sensitivity, convenience, environmental awareness and potential for behavioral change among air travel consumers.The findings from this study indicate that the algorithm will not act as a catalyst for emission reductions in the aviation sector, unless it is complemented by emission reduction policies and/or introduction of a fair emission taxation system. Furthermore, the aviation sector should be obliged to report accurate emission data on all tickets in order to bring full transparency to consumers searching low emission transport modes.

Energy return and production competitiveness of ekstrudat from grain mix and vegetable additive

Carrying out researches on extrusion of grain crops with inclusion of vegetable components and assessment of their energy value and competitiveness is an important task. Due to this quality indicator of the ekstrudat on the basis of wheat, barley, oats with inclusion of pulp of green grasses have been defined, the assessment of energy return and energy efficiency ratio has been carried out. The energy value of grain crops increased after extruding by 8.33 – 10.86%. The pulp of green grasses was mixed with seed of wheat or barley or oats in number of 10, 15 and 20% of the mass of mix. After mechanical dehydration of a grass mix the energy value of pulp was 10.68 MDzh/kg. At joint extruding of grain crops with pulp from a grass mix the power value of the ekstrudat decreased and was 0.12-0.21 MDzh/kg. Reduction of power value of the ekstrudat leads to decrease in power return by 0.12-0.21 MDzh/kg. At the same time the energy efficiency ratio is increased by 5.44-6.4%. Increase in power efficiency ratio is connected with reduction of energy input on grain crushing. Extrudat on the basis of wheat mix and 20% of pulp corresponded to the greatest value of energy return and energy efficiency ratio. The equations of linear regression have been received for the mathematical description of change of energy return and energy efficiency ratio. Use of pulp as a part of mix before extruding allows to receive a ready-made product with lower cost price in connection with reduction of grain mass as a part of the ekstrudat.

Multi‐objective optimisation design and performance comparison of permanent magnet synchronous motor for EVs based on FEA

The requirements of high efficiency, power density, and low price for the motor of electric vehicles (EVs) make the design of the driving motor become a process of multi-objective optimisation. For purpose of the permanent magnet synchronous motor (PMSM) used for EVs has the higher efficiency, wider range of speed regulation with flux-weakening and better cost superiority, a multi-objective optimisation design approach based on finite element analysis (FEA) and modified particle swarm optimisation (MPSO) algorithm which takes efficiency, flux-weakening rate, and price as optimisation objectives is proposed in this study. Five PMSMs with different rotor topologies (V-shape, U-shape, double V-shape, delta-shape, and double tangential-shape) are optimised by the proposed optimisation method and their performance characteristics, including flux-weakening ability, efficiency, price, and anti-demagnetisation ability, are compared. The results suggest that double V-shape rotor topology has the wider constant power range and double-layer PMs topology has stronger anti-demagnetisation ability and wider high efficiency interval, whereas single-layer topology has lower cost price. Furthermore, a PMSM prototype with V-shape PMs is manufactured, so that the feasibility of multi-objective optimisation design approach and accuracy of FEA are verified by prototype experiments.

Efficiency of application of new domestic fertilizers during fertigation in intensive apple tree plantations

The article presents the results of a comparative study of two fertigation systems of apple tree plantations, cultivated by intensive technology. The first system was mainly based on imported fertilizers of the OLIGOMAX range, the second system was based on domestic water-soluble fertilizers AQUA DROP and SOLAR. The purpose of the research was to estimate the efficiency of the use of domestic mineral fertilizers during fertigation in intensive apple tree plantations under conditions of the Krasnodar Territory. The application of mineral fertilizers in the dissolved form through the drip irrigation system was carried out during the growing season under dry conditions every 3-4 days. During the growing season 38 fertigations were carried out. Regular use of mineral fertilizers during the growing season contributed to the optimization of the water and nutrient regimes of the intensive apple tree plantations, by using both imported and domestic fertilizers. The use of domestic water-soluble fertilizers in the first year contributed to the optimization of the nutritional regime of the apple tree plantations, which was manifested in the increase in average mass of fruits by 2,5-3,2 g and the improvement in the formation of generative buds. In the second year of application of domestic fertilizers, the increase in the yield of apple trees by 4,3-5,8 t/ha was noted. An explicit advantage of using water-soluble fertilizers of the AQUA DROP and SOLAR range in fertigation is their lower cost price as compared to imported analogues. Even with the same potential yield of apple trees, the savings due to the use of domestic mineral fertilizers ranged from 17,8 to 28,5 thousand rubles/ha. In general, the use of domestic water-soluble mineral fertilizers in fertigation systems not only contributes to optimize the nutrition of apple trees, but also significantly improves the economic efficiency of fruit production.

Flavored cigar smoking among African American young adult dual users: An ecological momentary assessment

BackgroundFlavored cigar sales have increased in recent years in the U.S. African American young adults (AAYAs) have high prevalence of smoking flavored cigars and dual use with cigarettes, but the predictors of use are unclear. We examined the predictors of flavored cigar smoking among AAYA dual users. MethodsWe analyzed data from an Ecological Momentary Assessment (EMA) study that captured near real-time affect, smoking cues, and tobacco smoking from eight text-messaging surveys per day over two weeks. Sixty-three AAYA (ages 18–29) dual users of cigarettes and cigars recorded 1205 cigar smoking moments. Multivariable Generalized Estimating Equations were used to assess the predictors of smoking cigars with flavors and specific flavor types. ResultsHalf of the participants were women (49.2%) and aged between 18–24 (46.7%). Over the two-weeks, almost all (98.4%) participants smoked flavored cigars, and 64.2% of the cigars smoked were flavored. Alcohol (34.4%) was the most frequently smoked flavor type followed by sweet (23.4%) and mint (5.7%). Feeling stressed (AOR = 1.07) and bored (AOR = 1.10) predicted smoking alcohol flavors. Blunt smoking positively predicted smoking sweet flavors (AOR = 4.79), but negatively predicted smoking alcohol flavors (AOR = 0.40). ConclusionsSmoking flavored cigars, especially alcohol-flavored cigars, was prevalent among AAYA dual users in this study. This group might use specific flavors for different purposes including smoking blunts and boosting mood. Efforts to reduce cigar use need to tackle these risk factors and the increased marketing and low-cost pricing of cigars. A federal ban of cigar flavors might reduce the appeal of cigar products.

Promoting adaptive agility through modularity: a Chinese case

Organisational agility is currently a popular topic in a dynamic and uncertain environment as to the academic and practitioner communities. This paper, taking Hisense from China's manufacturing as a case, aims to reveal the building process and triggers of adaptive agility through R&D and production of Chinese flat-panel TVs from the perspective of modularity. This paper opens the black box between modularity and adaptive agility. It suggests that the adaptive systems of R&D and production are built through modularity. They can bring adaptive agilities including diversified varieties, advanced features, fast time-to-market, high quality and low cost (price). Enterprise achieves the balance of 'degree' and overall optimal performance price ratio.

Managing Opportunistic Consumer Returns in Retail Operations

Retailers use lenient return policies to stimulate demand and increase revenues, as such policies help customers assess uncertain product valuations at low (or no) return cost and yield higher equilibrium prices. However, generous refunds also yield unintended consequences such as opportunistic returns, which take place when customers intentionally rent a product for short term use. Accounting for 11% of all product returns in the United States in 2017, opportunistic returns prompt retailers to seek tactics to address adverse revenue and cost implications. We consider two alternative proposals using a price- and refund-setting newsvendor framework with two customer types: honest returners and renters. The first proposal, targeted-refunds, uses retail analytics firms to distinguish renters from honest returners, and implements return policies tailored for each segment. The second proposal, menu-of-refunds, presents customers multiple price-refund pairs, and lets them self-select. We compare and contrast the optimal decisions and the profit implications of both proposals with respect to two benchmark settings: one without any renters (Su, 2009), and another proposal, uniform-refunds, wherein the retailer merely re-optimizes its decisions while acknowledging that renters exist. We characterize the conditions under which the menu-of-refunds proposal separates customer types, and thus matching or exceeding the performance of the targeted-refunds proposal. Furthermore, we study several alternative model specifications to confirm that our main finding concerning the effectiveness of the menu-of-refunds proposal is robust.

Different Sensor Systems for the Application of Variable Rate Technology in Permanent Crops

The paper presents a review of different sensory systems for trees’ characterization and detection in permanent crops and the detection of plant health status in crop conditions for the purpose of applying the variable application rate. The use of new technologies enables the use of variable inputs in production with the aim of increasing the economic profit and reducing the negative impact on the environment. World trends increasingly emphasize the use of various sensor systems to achieve precision agriculture and apply the following: ultrasonic sensors for the detection of permanent crops; LIDAR (optical) sensors for treetop detection and characterization; infrared sensors with similar characteristics of optical sensors, but with very low cost prices and N - sensors for variable nitric fertilization. The daily development of sensor systems applied in agricultural production improves the performance and quality of the machines they are installed on. With a more intensive use of sensors in agricultural mechanization, their price becomes more acceptable for widespread use by achieving high quality work with respect to the ecological principles of sustainable production.

The (templar) knight cap: a new and simple way to prevent hair interference during ear surgery.

Hair interference is a critical problem in ear surgery. The hair around the surgical area can get stuck unwantedly, making the surgeon habitually struggling with this hair rather than the surgery itself. Hair shaving can cause psychological discomfort, especially for women and data about shaving efficacy are conflicting. With the aim of solving this problem, we developed a new way to clear hair from the operating field named "The (Templar) Knight cap". This is a medical elastic stocking open at the ear to be treated and at the face that recalls the typical cap worn by Templar knight. This cap allows good hair retention and marks the surgical site. It is easy to wear does not require additional time for clinical staff. The described cap could be a valid instrument during ear surgery with a low cost pricing, making it applicable in very poor settings, such as developing countries.

Research Regarding Capacitor Discharge Stud Welding with Tip Ignition on Galvanized Thin Sheets

Arc stud welding is a widely used welding process used to fix joints like studs, screws, pins, or similar elements on a wide variety of products. The process is mainly characterized by simplicity, high welding productivity, very good welding joint quality, low cost price, easy welding equipment and easy to handle, flexibility. The process successfully replaces other assembly methods such as: threaded assembly, riveting, classic arc welding or pressure welding and soldering. The paper proposes to establish welding technology for M5 x 35 mm steel stud with tip ignition and electric charge stored in capacitors on thin galvanized steel (s <1 mm thick). The main problem of welding galvanized steel is vaporization of zinc on the surface of the sheet which produces pores, splashes and very toxic fumes. This vaporization produces also the corrosion hazard in the surface of the sheet. Welding technology will be applied to joint stud on the cover of an air filter.

Innovation Policy and the Economy: Introduction to Volume 18

Innovation Policy and the Economy: Introduction to Volume 18

Defining the Fields for the Rational Application of Eddy Expansion Turbomachines by Using Criterion Systems

Low-power (up to 500 kW) expansion turbomachines (ETM) and the units based on them are frequently used for the solution of ecology and energy-saving problems to increase the reliability and the technological effectiveness of the equipment. When developing low-power units we face the problems related to a decrease in the efficiency of classic expansion turbomachines. Today, the market offers comparatively new low flow-rate eddy expansion turbomachines and as a result we have to define the fields for their rational application and their advantages in comparison with analogous options. This scientific paper defines the criterion systems for the comparative analysis of the performances of low flow- rate low-power ETM of a different type. The experimental data of investigation of the flow channels of eddy expansion machines with the external peripheral channel were analyzed and the relationships between the criterion systems used for eddy ETM were obtained and the fields for their rational application, in particular to develop low-power (up to 500 kW) low flow-rate and low-speed turbogenerators and turbodrives for the industry, municipal engineering and agriculture were defined. The main advantages of eddy expansion machines in comparison to axial or radial machines are their relatively simple design, technological effectiveness, low production cost price and comparatively low speed. Therefore, if the eddy ETM is used the unit can be designed using no reduction gear. The advantages of eddy expansion machines enable the manufacturing of a rather simple and reliable turbodrive or turbogenerator with the payback period of 1 to 2 years.

Self-Powered Pulse Sensor for Antidiastole of Cardiovascular Disease.

Cardiovascular diseases are the leading cause of death globally; fortunately, 90% of cardiovascular diseases are preventable by long-term monitoring of physiological signals. Stable, ultralow power consumption, and high-sensitivity sensors are significant for miniaturized wearable physiological signal monitoring systems. Here, this study proposes a flexible self-powered ultrasensitive pulse sensor (SUPS) based on triboelectric active sensor with excellent output performance (1.52 V), high peak signal-noise ratio (45 dB), long-term performance (107 cycles), and low cost price. Attributed to the crucial features of acquiring easy-processed pulse waveform, which is consistent with second derivative of signal from conventional pulse sensor, SUPS can be integrated with a bluetooth chip to provide accurate, wireless, and real-time monitoring of pulse signals of cardiovascular system on a smart phone/PC. Antidiastole of coronary heart disease, atrial septal defect, and atrial fibrillation are made, and the arrhythmia (atrial fibrillation) is indicative diagnosed from health, by characteristic exponent analysis of pulse signals accessed from volunteer patients. This SUPS is expected to be applied in self-powered, wearable intelligent mobile diagnosis of cardiovascular disease in the future.

Reduction in Difficulties of Phytomass Combustion by Co-Combustion of Wood Biomass

Nowadays, the most used biofuel in Slovak republic is log wood. Alternatively, there are also biofuels based on vegetal biomass (phytomass) like wheat straw or grass. The advantage of these biofuels is lower cost price because they are usually considered as waste product. The major disadvantage of these vegetal biofuels is their problematic combustion. It is mainly due to the low ash melting temperature because of chemical composition of ash from phytomass. The low ash melting temperature causes slagging and sintering, which reduce the efficiency of the combustion process. This disadvantage causes very difficult and problematic combustion of phytomass. The article deals the way of trouble reduction during combustion of pellets made from phytomass (specific hay) through the wood pellet co-combustion in a standard automatic boiler for combustion of wood pellets. During the experiments, the mixing ratio of hay pellets and wood pellets is varied and subsequently, there is determined its impact on the combustion process, namely on heat output of the boiler, and there is also evaluated the effect of the mixing ratio on the production of carbon monoxide (CO), nitrogen oxides (NOx), sulphur dioxide (SO2), organic hydrocarbons (OGC) and particulate matters (PM10, PM2.5).