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Evacuated tube solar collectors (ETSC) are widely utilized in both domestic and industrial solar water heaters (SWH) due to their commendable thermal performance and straightforward installation. However, a significant challenge associated with ETSC lies in the fact that half of the collector remains unexposed to sunlight. To overcome this limitation, parabolic reflectors can be employed as a viable solution. The primary objective of this study is to assess the performance of a compound parabolic concentrator (CPC) in conjunction with ETSC, taking into account a specific ratio between the areas of the CPC and ETSC. To achieve the desired configuration, the CPC was meticulously designed, fabricated, installed, and subsequently tested. Moreover, the energy performance of the absorber tube was scrutinized both with and without the integration of a parabolic trough collector. The experiments and data collection were conducted on two selected days for both the conventional ETSC device and the system incorporating the CPC. Meteorological data and operational conditions were measured and digitally stored for subsequent analysis. A noteworthy outcome of the study is the revelation that the energy efficiency of the system with a concentrator exhibited a notable improvement of 2.8% compared to the conventional system. Offline results further indicated that the performance of a single absorber tube with a concentrator increased by approximately 2.7 times when compared to the standard system. This suggests that the energy performance of the solar water heater, with a capacity of about 200 liters and featuring 7 absorber tubes with a concentrator, is comparable to that of the conventional system equipped with 18 absorber tubes.

Purpose — This study investigates the determinants of Islamic banks' stability in Indonesia amidst the Covid-19 pandemic. Method — Employing a causality-associative quantitative approach, the research utilizes purposive sampling and secondary data collection from monthly financial reports on the official websites of OJK (Financial Services Authority) and BI (Bank Indonesia). Statistical techniques including normality test, multicollinearity test, t-test, f-test, R2 test, and multiple linear regression, aided by SPSS version 22 and Microsoft Excel, are employed for data analysis. Result — The results reveal that Islamic banks' total assets significantly positively influence their stability in Indonesia. Additionally, variables such as Operational Costs to Operational Income (OCOI) ratio and BI 7-Day Reverse Repo Rate (BI7DRR) exhibit significant negative effects on Islamic banks' stability. Practical implications — Understanding the influence of total assets, Operational Costs to Operational Income (OCOI) ratio, and the BI 7-Day Reverse Repo Rate (BI7DRR) on Islamic banks' stability in Indonesia during the Covid-19 pandemic can guide policymakers and bank management in implementing measures to strengthen resilience and mitigate risks, such as strategic asset management and cost optimization strategies.

The present study investigates the applicability of inexpensive natural clay sepiolite as a solid support for preparing sulfonic acid functionalized nanocatalysts producing biodiesel as an alternative fuel. The nanocatalyst is characterized by standard analyses such as XRD, FT-IR, BET, and FE-SEM to evaluate its physical and chemical properties. To avoid soap formation in the transesterification process and to modify the functionality of a mineral-grade sepiolite, sulfonic acid (Sep-SO3H) has been used to enhance its activity and stability. The resulting heterogeneous catalyst is a nanosized solid acid that can handle edible waste oil as a low-value feedstock with high levels of impurities and acidity in the feedstock. The biodiesel production efficiency is determined by GC-mass spectrometry. Using 2 wt.% of the nanocatalyst resulted in a conversion of 94.7% of the waste cooking oil, demonstrating the high efficiency and promising potential of the materials and method, considering the nature of the feedstock and excellent recycling performance.

Tujuan: Mengetahui hubungan antara RNL dan kadar IL-6 dengan waktu konversi negatif pada pasien rawat inap COVID-19. Metode: Penelitian cross sectional dengan 50 berkas rekam medis pasien rawat inap COVID – 19 di RSUP Dr. M. Djamil Padang periode Januari 2021 sampai Desember 2021. Pengolahan data menggunakan aplikasi SPSS dengan uji korelasi Pearson karena data terdistribusi normal. Hasil: Hasil penelitian menunjukkan bahwa tidak terdapat hubungan yang signifikan antara nilai RNL dengan waktu konversi, sedangkan antara kadar IL-6 dengan waktu konversi terdapat hubungan yang signifikan. Kesimpulan: tidak terdapat hubungan yang signifikan antara RNL dengan waktu konversi negatif dan terdapat hubungan yang signifikan antara kadar IL-6 dengan waktu konversi negatif COVID – 19 pada pasien yang menjalani rawat inap.

Recently, there has been a growing demand for Rattan baby cribs in the international market, primarily due to aesthetic appeal of handwoven rattan. Given that these cribs are intended for infants, safety is a paramount concern alongside aesthetics. Previous research identified a potential risk of limb injury in infants aged 5-12 months due to inconsistent rattan gap decorations exceeding 60 mm in crib width. However, achieving standard gap dimensions in conventional handcrafted production methods has been challenging. This study aims to investigate safety, aesthetics, and manufacturing efficiency in Rattan baby crib production through Focus Group Discussion (FGD) involving research designers, the Research and Development (R&D) Department, the production department, the marketing division, and expert guest designers. Rattan with a diameter of 22 mm and a consistent gap width below 60 mm, is utilized. The crib’s structural elements will apply simple, robust, straight rattan weaving. Visual design recommendation encompasses natural luxury, playfulness, and safety. Various rattan types that balance aesthetics and strength, including thinner-diameter rattan with intricate weaving as non-structural aesthetic elements and side-by-side dual system, enhance beauty while meeting strength and material efficiency requirements. The development of Rattan baby cribs, focusing on child safety and aesthetics, is highly demand due to increasing market demand in the United States, Australia, and Europe and potential opportunities in the local market.

Urban farming activities in Malang City have increased during the COVID-19 pandemic. This study responds to the threat of a food crisis due to the continued impact of the COVID-19 pandemic. Massive implementation of urban farming can provide different perceptions and goals depending on the characteristics of each individual, including differences in occupation, gender, and age. This research aimed to investigate the perspective on the implementation of urban farming during the COVID-19 pandemic. It is a critical reflection study to determine what factors affected the implementation of urban farming in supporting food security in Malang City. The study was conducted in Lowokwaru District, Sukun District, and Blimbing District, with 30 participants. The findings indicated that the success of urban farming in Malang City was affected by various factors. For instance, the growing interest in urban farming, urban farming contests, and social activities. It also could support food security in urban areas during the COVID-19 pandemic. In addition, the existence of farmer group communities and the role of the government and the wider community can contribute to the success of urban farming.

Research on Islamic economics experienced rapid development in recent years along with the development of Islamic economics as a branch of science throughout the world, especially in Muslim countries. This paper aims at mapping and observing the trend of Islamic economic studies listed on SINTA, the official Indonesian indexing website. The sampling data for this study is 114 published papers obtained from the website. The data are analyzed using quantitative descriptive with bibliometric analysis method. This study found that most papers are published by “Al-Iqtishad: Jurnal Ilmu Ekonomi Syariah”, owned by Syarif Hidayatullah State Islamic University. The qualitative approach is most used by research samples in this study with 74 papers (64.91%), while quantitative is only used by 40 papers (35.08%). It also found that Islamic economic research in Indonesia is dominated by Islamic bank topics with several general bank keywords, such as efficiency, profitability, liquidity, and Non-Performing Financing (NPF). This study suggested that further researchers conduct more studies on Islamic or Sharia values implemented within Islamic banks since it is the main difference between Islamic and conventional banks. Further studies can also observe broader problems like poverty and how the Islamic economy has overcome this issue ==================================================================================================== ABSTRAK – Pemetaan Tren Kajian Ekonomi Islam pada Pengindeks SINTA: Suatu Analisis Bibliometrik. Penelitian di bidang ekonomi Islam mengalami perkembangan yang cukup signifikan beberapa tahun terakhir bersamaan dengan perkembangan ekonomi Islam sebagai salah satu cabang ilmu pengetahuan, terutama di negara-negara dengan mayoritas penduduknya adalah Muslim. Artikel ini bertujuan untuk melakukan pemetaan dan melihat tren publikasi pada artikel penelitian ekonomi Islam yang terindeks SINTA, website pengideks resmi Indonesia. Sebanyak 114 artikel diperoleh dari SINTA untuk dijadikan sebagai sampel penelitian. Metode yang digunakan adalah deskriptif kuantitatif dengan analisis bibliometrik. Penelitian ini menemukan bahwa mayoritas paper dipublikasikan oleh “Al-Iqtishad: Jurnal Ilmu Ekonomi Syariah” dari UIN Syarif Hidayatullah Jakarta. Pendekatan kualitatif digunakan oleh 74 sampel artikel (64.91%), sementara pendekatan kuantitatif digunakan oleh 40 artikel (35.08%). Studi ini juga menemukan bahwa artikel kajian ekonomi Islam di Indonesia masih didominasi oleh penelitian terkait bank syariah dengan beberapa kata kunci, diantaranya: efisiensi, profitabilitas, likuiditas, dan Non-Performing Financing (NPF). Penelitian ini merekomendasikan kepada para peneliti di bidang ekonomi Islam untuk melakukan kajian lebih mendalam pada nilai-nilai Syariah yang diimplementasikan di bank Syariah karena hal tersebut merupakan perbedaan mendasar antara bank Syariah dan bank konvensional. Isu lebih luas terkait kemiskinan dan bagaimana ekonomi Islam mengatasinya juga dapat diteliti secara lebih komprehensif dalam kerangka penelitian ekonomi Islam.

Flexible and stretchable power sources represent a key technology for the realization of wearable electronics. Developing flexible and stretchable batteries with mechanical endurance that is on par with commercial standards and offer compliance while retaining safety remains a significant challenge. We present a unique approach that demonstrates mechanically robust, intrinsically safe silver-zinc batteries. This approach uses current collectors with enhanced mechanical design, such as helical springs and serpentines, as a structural support and backbone for all battery components. We show wire-shaped batteries based on helical band springs that are resilient to fatigue and retain electrochemical performance over 17,000 flexure cycles at a 0.5-cm bending radius. Serpentine-shaped batteries can be stretched with tunable degree and directionality while maintaining their specific capacity. Finally, the batteries are integrated, as a wearable device, with a photovoltaic module that enables recharging of the batteries.

Widespread deployment of EcoBlocks has the potential to transform today's electricity system into one that is more resilient, flexible, efficient and sustainable. In this vision, the system will consist of self- su cient, renewable-powered, block-scale entities that can deliberately adjust their net power exchange and can optimize performance, maintain stability, support each other, or disconnect entirely from the grid as needed. This report is intended as an independent analysis of the potential relationships, both constructive and adverse, between EcoBlocks and the grid.

Purpose — To ascertain the development strategy used to establish tourism communities and the economic impact on the community. Research method — This study employs a qualitative approach with interview as the data collection method which is sourced from the head of the tourism awareness group (POKDARWIS) and tourism business actors, including songket artisans, guiders, small traders, breeders, employees of tourist attractions, lodging services, art studios, travel services, compass fertilizer businesses, village heads, and the community. Result — The study's findings include the development model that was used to develop Setanggor Tourism Village, namely the Community Based Tourism development model which entails three components: community participation in decision-making, community involvement in businesses and profit generation, and resource empowerment and profit distribution. The growth of this tourism village has a significant impact on people's income, employment possibilities, prices, community ownership and control, and tourism objects.

The objective of this study is to look at how Malaysian small and medium enterprises (SMEs) are applying eco-innovation capabilities in order to sustain their business performance. Eco-innovation capabilities are represented in this study by five different types of practices, with the indication of unexpected circumstances: eco-product innovation, eco-process innovation, eco-organisational innovation, eco-marketing innovation, and eco-technology innovation. The qualitative research approach was used in the study, and the content analysis was based on in-depth interviews with six top-level managers/owners of Malaysian manufacturing SMEs. According to the data, more than half of SMEs acquired eco-innovation capabilities in order to continue their business performance and thrive in the business sector, while having to confront certain hurdles due to unforeseen situations. According to the findings, eco-innovation capabilities encourage SMEs to engage in waste management, recycling or reusing resources, research and development, sustainable goods that utilize customer requests, and the use of environment management machines. Thus, the findings of this study may aid the efforts of government agencies, policymakers, and top-tier manufacturing SMEs in building an exceptional innovation platform on which SMEs may rely for assistance and support in preserving their business performance in the future and beyond.

Purpose — This study investigates the determinants of Islamic banks' stability in Indonesia amidst the Covid-19 pandemic. Method — Employing a causality-associative quantitative approach, the research utilizes purposive sampling and secondary data collection from monthly financial reports on the official websites of OJK (Financial Services Authority) and BI (Bank Indonesia). Statistical techniques including normality test, multicollinearity test, t-test, f-test, R2 test, and multiple linear regression, aided by SPSS version 22 and Microsoft Excel, are employed for data analysis. Result — The results reveal that Islamic banks' total assets significantly positively influence their stability in Indonesia. Additionally, variables such as Operational Costs to Operational Income (OCOI) ratio and BI 7-Day Reverse Repo Rate (BI7DRR) exhibit significant negative effects on Islamic banks' stability. Practical implications — Understanding the influence of total assets, Operational Costs to Operational Income (OCOI) ratio, and the BI 7-Day Reverse Repo Rate (BI7DRR) on Islamic banks' stability in Indonesia during the Covid-19 pandemic can guide policymakers and bank management in implementing measures to strengthen resilience and mitigate risks, such as strategic asset management and cost optimization strategies. [ABSTRACT FROM AUTHOR]

Priapism in chronic myeloid leukemia (CML) appears to be an infrequent manifestation as well as a crucial emergency. Here, we report an 18-year-old male presenting with a persistent erection of the penis for 20 days. We evaluated and compared the reported cases within 20 years discussing the management of priapism in CML. Cytoreductive therapy followed by leukapheresis, the administration of tyrosine kinase inhibitor, and intra-cavernosal blood aspiration may resolve the symptoms of priapism. Early intervention for cytoreduction and aspiration are the pivotal keys to successfully impeding the complications.

This paper reports on the design and operation of a flexible power source integrating a lithium ion battery and amorphous silicon solar module, optimized to supply power to a wearable health monitoring device. The battery consists of printed anode and cathode layers based on graphite and lithium cobalt oxide, respectively, on thin flexible current collectors. It displays energy density of 6.98 mWh/cm(2) and demonstrates capacity retention of 90% at 3C discharge rate and ~99% under 100 charge/discharge cycles and 600 cycles of mechanical flexing. A solar module with appropriate voltage and dimensions is used to charge the battery under both full sun and indoor illumination conditions, and the addition of the solar module is shown to extend the battery lifetime between charging cycles while powering a load. Furthermore, we show that by selecting the appropriate load duty cycle, the average load current can be matched to the solar module current and the battery can be maintained at a constant state of charge. Finally, the battery is used to power a pulse oximeter, demonstrating its effectiveness as a power source for wearable medical devices.

This paper reports on the design and operation of a flexible power source integrating a lithium ion battery and amorphous silicon solar module, optimized to supply power to a wearable health monitoring device. The battery consists of printed anode and cathode layers based on graphite and lithium cobalt oxide, respectively, on thin flexible current collectors. It displays energy density of 6.98 mWh/cm(2) and demonstrates capacity retention of 90% at 3C discharge rate and ~99% under 100 charge/discharge cycles and 600 cycles of mechanical flexing. A solar module with appropriate voltage and dimensions is used to charge the battery under both full sun and indoor illumination conditions, and the addition of the solar module is shown to extend the battery lifetime between charging cycles while powering a load. Furthermore, we show that by selecting the appropriate load duty cycle, the average load current can be matched to the solar module current and the battery can be maintained at a constant state of charge. Finally, the battery is used to power a pulse oximeter, demonstrating its effectiveness as a power source for wearable medical devices.

Priapism in chronic myeloid leukemia (CML) appears to be an infrequent manifestation as well as a crucial emergency. Here, we report an 18-year-old male presenting with a persistent erection of the penis for 20 days. We evaluated and compared the reported cases within 20 years discussing the management of priapism in CML. Cytoreductive therapy followed by leukapheresis, the administration of tyrosine kinase inhibitor, and intra-cavernosal blood aspiration may resolve the symptoms of priapism. Early intervention for cytoreduction and aspiration are the pivotal keys to successfully impeding the complications.

While programs have been established to support secondary level English Learners (ELs) in their transition to institutions of higher education (IHEs), limited attention has been given to how to support adult ELs who struggle with the academic language demands of their college or university content-area courses. Research indicates that many EL students frequently struggle with academic language skills, including grammar, vocabulary, and writing throughout their postsecondary schooling. Nevertheless, IHE instructors often lack the knowledge and skills to provide appropriate assistance to these students, in part because there are so few professional development opportunities available that are designed to help instructors meet the academic needs of ELs in their content-area courses. The authors believe that it is imperative that teacher education faculty recognize and attend to the academic language struggles of EL student teachers, while also embracing the rich cultural and linguistic capital that these new teachers bring to the profession. While it is necessary to ensure that all teachers who enter the K-12 school system can support their students who are ELs by effectively modeling and teaching academic English, it is equally important that teacher candidates of diverse backgrounds are supported and encouraged throughout their teacher preparation coursework and experiences. This article details specific, research-based feedback strategies that the authors have found useful in working with and supporting the academic language development of EL preservice secondary teachers. The authors organize and discuss these feedback strategies in terms of the following four themes: (1) focused feedback on student writing; (2) focused feedback on oral communication; (3) explicit modeling; and (4) revision and assessment. (Contains 3 figures and 1 note.)

Additive and low-temperature printing processes enable the integration of diverse electronic devices, both power-supplying and power-consuming, on flexible substrates at low cost. Production of a complete electronic system from these devices, however, often requires power electronics to convert between the various operating voltages of the devices. Passive components-inductors, capacitors, and resistors-perform functions such as filtering, short-term energy storage, and voltage measurement, which are vital in power electronics and many other applications. In this paper, we present screen-printed inductors, capacitors, resistors and an RLC circuit on flexible plastic substrates, and report on the design process for minimization of inductor series resistance that enables their use in power electronics. Printed inductors and resistors are then incorporated into a step-up voltage regulator circuit. Organic light-emitting diodes and a flexible lithium ion battery are fabricated and the voltage regulator is used to power the diodes from the battery, demonstrating the potential of printed passive components to replace conventional surface-mount components in a DC-DC converter application.

Priapism in chronic myeloid leukemia (CML) appears to be an infrequent manifestation as well as a crucial emergency. Here, we report an 18-year-old male presenting with a persistent erection of penis for 20 days. We evaluate and compare the reported cases during the past 20 years discussing the management of CML patients experiencing priapism. Cytoreductive therapy followed by leukapheresis, the administration of tyrosine kinase inhibitor, and intra-cavernosal blood aspiration may resolve the symptoms of priapism. Early intervention for cytoreduction and aspiration are the pivotal keys to successfully impeding the complications.

Evacuated tube solar collectors (ETSC) are widely utilized in both domestic and industrial solar water heaters (SWH) due to their commendable thermal performance and straightforward installation. However, a significant challenge associated with ETSC lies in the fact that half of the collector remains unexposed to sunlight. To overcome this limitation, parabolic reflectors can be employed as a viable solution. The primary objective of this study is to assess the performance of a compound parabolic concentrator (CPC) in conjunction with ETSC, taking into account a specific ratio between the areas of the CPC and ETSC. To achieve the desired configuration, the CPC was meticulously designed, fabricated, installed, and subsequently tested. Moreover, the energy performance of the absorber tube was scrutinized both with and without the integration of a parabolic trough collector. The experiments and data collection were conducted on two selected days for both the conventional ETSC device and the system incorporating the CPC. Meteorological data and operational conditions were measured and digitally stored for subsequent analysis. A noteworthy outcome of the study is the revelation that the energy efficiency of the system with a concentrator exhibited a notable improvement of 2.8% compared to the conventional system. Offline results further indicated that the performance of a single absorber tube with a concentrator increased by approximately 2.7 times when compared to the standard system. This suggests that the energy performance of the solar water heater, with a capacity of about 200 liters and featuring 7 absorber tubes with a concentrator, is comparable to that of the conventional system equipped with 18 absorber tubes. [ABSTRACT FROM AUTHOR]

In this research, a comprehensive simulation study including 3-D Dynamic time-dependent has been performed for Phase Change Materials (PCMs) applicant as a thermal storage integrated with the wind-catcher-wall in order to reduce the temperature difference (As a sustainable cooling method) in the MATLAB open-source–code software. By means of 3-D Dynamic time-dependent, as a final finding, the temperature drop (Cooling purpose) was obtained 25 degrees at about 7 working hours. Passive cooling can be considered as a viable and attractive strategy for the sustainable concept, opposed to mitigation of energy consumption and Green House Gas (GHG) simultaneously. One of the traditional-old-age famous passive cooling systems that are still being applied nowadays is wind-catcher as an energy system. The wind catcher sustain natural ventilation and cooling in buildings through wind-driven airflow as well as temperature difference. Windcatchers can save the electrical energy used to provide thermal comfort during the hot climate in summer case of the year, especially during the peak hours contributed to energy carriers’ consumptions. In this study, by proposing a new design of the windcatchers, attempts have been made to improve the energy efficiency of passive cooling methods. Besides, the application of new efficient methods for the purpose of thermal energy storage (PCM) as a sub-system is a chosen method to increase energy efficiency. By applying energy storage systems in addition to increase system energy performance and reliability, the target of reducing energy consumption is achieved. © 2019. CBIORE-IJRED. All rights reserved Article History: Received May 18th 2018; Received in revised form October 5th 2018; Accepted January 5th 2019; Available online How to Cite This Article: Seidabadi, L., Ghadamian, H, and Aminy, M. (2019) A Novel Integration of PCM with Wind-Catcher Skin Material in Order to Increase Heat Transfer Rate. Int. Journal of Renewable Energy Development, 8(1), 1-6. https://doi.org/10.14710/ijred.8.1.1-6

In this study, the forced convective in a tube filled with porous media is investigated analytically based on the perturbation methods. Thermal conductivity of the medium is assumed to be a linear function of radius. The Brinkman–Forchheimer-extended Darcy and local thermal equilibrium models are applied for momentum and energy equations. Analytical expressions for the temperature profile and Nusselt number as functions of porous medium shape parameter and thermal conductivity variation parameter are introduced. An analytical expression of the Nusselt number based on a variable conductivity with radius for the extended model of Darcy–Brinkman–Forchheimer has not been previously proposed, and the present study aims at filling this gap. The effects of porous media shape parameter (s), Forchheimer number (F) and linear parameter of conductivity (ɛ) on the Nusselt number and temperature profile are discussed. Results show that the Nusselt number increases with a linear increase in the thermal conductivity of the medium. Keywords: Porous media, Variable conductivity, Brinkman–Forchheimer–Darcy model, Perturbation analysis

Indigenous fruits such as bananas, jackfruit, and pineapple have sensory characteristics that many people like. However, these fresh fruits have a short shelf life. Processing Fruit chips using vacuum frying is one solution to extend the shelf life of fruit with good quality and nutrition content. This study aimed to obtain the proximate composition value of fresh fruit and vacuum fried fruit chips. The research method used proximate analysis based on water, carbohydrate, lipid, crude protein, crude fibre, and ash content. The results showed a significant difference in the water, carbohydrate, lipid, and ash content between fresh fruits and vacuum fried fruit chips. Meanwhile, in crude protein and crude fibre content, there was no significant difference. The water content of fresh fruits was higher than the vacuum-fried fruit chips. The carbohydrate, lipid, crude protein, and ash content of vacuum fried fruit chips were higher than the fresh fruits. The crude fibre of pineapple vacuum fried chips was higher than fresh pineapple. However, the crude fibre of fresh jackfruit and banana was higher than the vacuum fried fruit chips.