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Recently, Blockchain-based applications have become immensely popular because of limited reliance on a single entity, unlike a centralized system. However, reaching a consensus among blockchain networks is a challenging and vital aspect of blockchain-based applications. There are various types of blockchain networks for different kinds of application scenarios. Among all of them, the consensus algorithm is the most crucial part of reaching an agreement in the complex blockchain network. Over the years, researchers have focused on dealing with the challenges like distributed computing, storage, transaction speed, security, validity, interoperability, and many more. However, only some of them are appropriate for all domains. Therefore, this paper presents an extensive study of different types of consensus protocols used in existing blockchain solutions with the strength and limitations of each algorithm. We also provide an inherent comparison among different algorithms to understand consensus protocol selection better. Moreover, we investigate operational and interoperability issues in existing blockchain-based applications to understand challenges and provide recommendations for future developers.

Background: Despite annual rounds of mass drug administration (MDA) being carried out every year since 2004 to break the transmission of lymphatic filariasis, India has not achieved elimination status in many areas of country. This study was conducted to determine the operational issues in the implementation of MDA for elimination of lymphatic filariasis in selected districts of Jharkhand. Methods: Two districts of Jharkhand state were selected for present cross-sectional study. Multi-staged cluster sampling was adopted to select study participants. Data were collected with use of prescribed questionnaire of National Vector Borne Disease Control Programme (NVBDCP) from the study participants. Data related to socio-demographic details, coverage and compliance of MDA and operational issues were collected. Results: Findings of independent assessment show that percentage of MDA coverage and compliance for Hazaribag district was 96.02% and 88.90%, respectively. On the other hand, percentage of MDA coverage and compliance was found to be only 67.06% and 48.44% in Chatra district. Overall drug consumption was significantly associated with age group (p-value = 0.045), educational status (p-value =

Background: Despite annual rounds of mass drug administration (MDA) being carried out every year since 2004 to break the transmission of lymphatic filariasis, India has not achieved elimination status in many areas of country. This study was conducted to determine the operational issues in the implementation of MDA for elimination of lymphatic filariasis in selected districts of Jharkhand. Methods: Two districts of Jharkhand state were selected for present cross-sectional study. Multi-staged cluster sampling was adopted to select study participants. Data were collected with use of prescribed questionnaire of National Vector Borne Disease Control Programme (NVBDCP) from the study participants. Data related to socio-demographic details, coverage and compliance of MDA and operational issues were collected. Results: Findings of independent assessment show that percentage of MDA coverage and compliance for Hazaribag district was 96.02% and 88.90%, respectively. On the other hand, percentage of MDA coverage and compliance was found to be only 67.06% and 48.44% in Chatra district. Overall drug consumption was significantly associated with age group (p-value = 0.045), educational status (p-value = <0.0001) and socio-economic status (p-value <0.0001) of eligible population. Most common reason for not swallowing the drugs was found to be absence of family members at the time of MDA rounds followed by no visit of house by drug distributors. Conclusions: Coverage and compliance of MDA was better in Hazaribag district as compared to Chatra district. In order to increase compliance, socio-demographic factors must also be addressed apart from other operational issues. [ABSTRACT FROM AUTHOR]

Domain Name System (DNS) is a fundamental component for today’s Internet communications, enabling the domain-to-IP translations for billions of users and numerous applications. Yet, the operational failures of DNS are not rare and sometimes lead to severe consequences like Internet outages. To gain a better understanding of DNS operational failures, previous works examined large-scale DNS logs (DNS queries and responses between Internet users and DNS servers), but the DNS logs cannot offer a comprehensive view of the failures (e.g., errors at domain registrars) and explain the failures at a finer grain. In this paper, we try to assess DNS operational failures from another data source, the supporting forums built by DNS service providers. Specifically, we mined 4 DNS forums and crawled more than 10000 posts and 50000 replies. With a new analysis framework developed by us, we are able to tag the forum posts by different categories (e.g., general concerns, issue locations, and record types), and gain new insights regarding how and why users encounter DNS failures. In the end, we offer suggestions to DNS service providers and users to mitigate DNS operational issues.

Abstract One of the main challenges associated with the operation and maintenance of binary geothermal power plants is the degradation of construction materials. In this sense, it is crucial to apply appropriate preventive maintenance in critical components (such as the wellheads, heat exchangers, or pipes), while reducing shutdown times. Based on electrochemical measurements performed in an autoclave corrosion testing setup, we studied the corrosion mechanism of API L80 steel grade as a function of operational and/or maintenance procedures. We used a test fluid representative for a site in Switzerland, but the main observations made may be applicable in a wider context. We found that changes in the fluid temperature (from 200 to 100 °C) or temporary oxygen ingress significantly influenced the corrosion behavior of this carbon steel and increased its corrosion rate (from approx. 20 µm/year to > 120 µm/year). After a few days, the corrosion rate was found to decrease and stabilize around values of 50–70 µm/year, as a result of a porous corrosion product layer formed on the metal surface (approx. 250 µm thick). Electrochemical impedance spectroscopy indicated an increase in capacitance of the double layer over time, most likely due to an increase in the effective surface area of the steel sample, as a consequence of surface roughening due to corrosion. The results from this study may be implemented in the design and operation of future power plants in Switzerland and elsewhere to ensure reliable and cost-effective energy production from geothermal resources.

Medical libraries are continual sources of knowledge and information. Without this knowledge and information, there will be no researcher, teacher, and doctor. Libraries cannot share knowledge with knowledge seekers alone. In this scenario, the role of the librarian becomes very influential. A librarian is an information services provider. The providence of these services is dependent on the facilities which are required by librarians. Realizing the importance of this issue the researcher has carried out research to investigate issues faced by librarians while operating medical library services. This study was related to quantitative research methodology; therefore, the researcher adopted quantitative research methodology for this research work. The presented issue in this study was solved through collecting data, with the help of using different techniques associated with data collection techniques, description of collected data, analyzing collected data and then finding the solution to the problem after a detailed analysis of data. In this study, the university libraries located in Islamabad were the population of the study to collect data regarding library operational issues in medical university libraries in Islamabad. The findings of the study show that medical librarians are facing numerous issues. These issues are impending medical librarians to operate library services in effective and appropriate ways. So, this research work suggests that the budget of libraries should be increased, medical librarians should be trained to meet their challenges, and medical resources and digital resources ought to be augmented in the respective universities in Islamabad. The aforementioned strategies can be useful for medical libraries and can enable librarians to operate their library services in more influential and effective ways in terms of information providers. [ABSTRACT FROM AUTHOR]

Abstract This article aims to analyze the implementation of musyarakah mutanaqishah financing on Islamic banking in Indonesia, especially in facing the existence of three issues available in contract implementation (sharia issues, legal issues, and operational issues). The research method used in this research is descriptive qualitative method with an inductive analysis approach. The method of analyzing the date is based on Law of Republic of Indonesia Number 21/2008 concerning Sharia Banking, DSN-MUI, Fatwa Number 73/2008 concerning Musyarakah Mutanaqishah, and AAOIFI Sharia Standards. The research findings showed that the implementation of MMQ on some points is not based on sharia law. In terms of legal and operational analysis based on BI rules on banking laws, there are indications of a discrepancy between the basic rules and its implementation in the field. The operational assignment of all payment obligations for fees deviates from AAOIFI standards and DSN fatwas, and there are no specific accounting standards related to MMQ . Abstrak Artikel ini bertujuan menganalisis implementasi pembiayaan musyarakah mutanaqishah pada perbankan syariah di Indonesia, terutama dalam menanggapi keberadaan tiga isu yang melekat pada implementasi akad (isu syariah, isu legal, dan isu operasional). Metode penelitian yang digunakan adalah metode kualitatif deskriptif dengan pendekatan analisis induktif. Analisis dilaksanakan berdasarkan Undang-Undang Republik Indonesia Nomor 21 Tahun 2008 Tentang Perbankan Syariah, Fatwa DSN-MUI Nomor 73/2008 tentang Musyarakah Mutanaqishah, dan Standar Syariah AAOIFI. Hasil analisis menunjukkan bahwa implementasi MMQ pada beberapa point belum sesuai syariah. Dari sisi analisis legal dan operasional berdasarkan aturan BI tentang undang-undang perbankan terindikasi adanya ketidaksesuaian antara dasar aturan dengan implementasi di lapangan.Terkait operasional adanya pelimpahan semua kewajiban pembayaran atas biaya yang muncul menyimpang dari standar AAOIFI dan fatwa DSN dan belum ada standar akuntansi khusus terkait MMQ.

Increased adoption of distributed energy resources in the form of renewable energy sources (RESs) to handle the capacity expansion in the power distribution system (PDS) is a new paradigm. RESs being intermittent in nature, present operational issues that worsen with increasing RES penetration rate. An attractive approach for handling the intermittency is coordinated reactive power control (RPC) of the RESs in the PDS. RPC leverages on the reactive power capacity of the RES inverters and hence is a significantly cheaper option than the conventional solutions such as energy storage systems. Oversizing of inverters is considered to improve the robustness of RPC, however, malicious attackers may exploit the oversized capacity to strengthen their attacks. In this study, a demonstration of data integrity attacks launched against RPC and its impact on the availability of the power supply at the prosumer premises are presented. Validation for the attack using simulations and emulated experiments in a scaled‐down power system test‐bed is also presented. The analytical, simulation and experimental results illustrate the feasibility of tripping the circuit breaker at the prosumer site and causing power supply interruption. Finally, a defense mechanism is proposed to minimise the impacts and it is validated using MATLAB–SIMULINK simulations. [ABSTRACT FROM AUTHOR]

One of the main challenges associated with the operation and maintenance of binary geothermal power plants is the degradation of construction materials. In this sense, it is crucial to apply appropriate preventive maintenance in critical components (such as the wellheads, heat exchangers, or pipes), while reducing shutdown times. Based on electrochemical measurements performed in an autoclave corrosion testing setup, we studied the corrosion mechanism of API L80 steel grade as a function of operational and/or maintenance procedures. We used a test fluid representative for a site in Switzerland, but the main observations made may be applicable in a wider context. We found that changes in the fluid temperature (from 200 to 100 °C) or temporary oxygen ingress significantly influenced the corrosion behavior of this carbon steel and increased its corrosion rate (from approx. 20 µm/year to > 120 µm/year). After a few days, the corrosion rate was found to decrease and stabilize around values of 50–70 µm/year, as a result of a porous corrosion product layer formed on the metal surface (approx. 250 µm thick). Electrochemical impedance spectroscopy indicated an increase in capacitance of the double layer over time, most likely due to an increase in the effective surface area of the steel sample, as a consequence of surface roughening due to corrosion. The results from this study may be implemented in the design and operation of future power plants in Switzerland and elsewhere to ensure reliable and cost-effective energy production from geothermal resources. [ABSTRACT FROM AUTHOR]

This paper focuses on exploring the leadership governance in universities. The leadership governance creates an environment which is transparent and it incorporates stakeholders that transform the university. The leadership governance faces visible and invisible challenges which calls for experts in different areas of leadership to be incorporated into the structures of the university in order to bring sustainability in the university. The primary data was collected from six traditional universities and three universities of technology in South Africa from the sample of 39 members of senate. The nature of the study is a quantitative study in which Survey Monkey was used for the distribution of questionnaires. The findings of the study indicate that there is a lack of involvement of stakeholders in the processes of reviewing policies and operational issues. The other findings was the use of university members in leadership to promote unity.

Biomass with a large amount of moisture is well-suited to be processed by supercritical water gasification, SCWG. The precipitation of inorganics, together with char formation and re-polymerization, can cause reactor plugging and stop the process operations. When plugging occurs, sudden injections of relatively large mass quantities take place, influencing the mass flow dynamics significantly in the process. Reactor plugging is a phenomenon very well observed during SCWG of industrial feedstock, which hinders scale-up initiatives, and it is seldom studied with precision in the literature. The present study provides an accurate evaluation of continuous tubular reactor dynamics in the event of sudden injections of water. An interpretation of the results regarding water properties at supercritical conditions contributes to comprehending mass and heat transfer when plugging occurs. Experiments are then compared to SCWG of a biomass sample aiming to give key insights into heat transfer and fluid dynamics mechanisms that could help develop operational and control strategies to increase the reliability of SCWG. In addition, a simplified model is presented to assess the effect of material integrity on burst-event likelihood, which states that SCWG is safe to operate, at 250 bar and 610 °C, in tubular reactors made of 0.22 wall thickness-to-diameter ratio Inconel-625 with superficial microfractures smaller than 30 µm. We also suggest improvement opportunities for the safety of SCWG in continuous operation mode.

In Switzerland, deep geothermal energy can give a promising contribution to the future energy scenario. However, the expertise in operational issues of deep geothermal power plants is limited, and technical challenges, such as corrosion, are a determining factor for their reliable and long-term operation. In this work, two representative fluids of optimal geothermal conditions in Switzerland were studied. The corrosiveness of the solutions was assessed using two experimental setups that allow investigating the range of temperatures and pressures that apply to the reservoir and power plant conditions. The corrosion behaviour of API L80 steel was analyzed by means of electrochemical measurements (at 100 and 200 ∘ C ) and of gravimetric tests (at 100 ∘ C ). After the tests, the morphologies and composition of the corrosion products were obtained by scanning electron microscopy (SEM) coupled with energy dispersive X-Ray (EDX) and X-Ray diffraction (XRD). Results show that corrosion rates are significantly high at 100 ∘ C in environments with a chloride concentration of around 600 mg/L and pH around 7. The corrosion products deposited on the metal surface mainly consist of magnetite and/or hematite that might potentially form a protective layer. This study gives a first insight of the potential corrosiveness of geothermal fluids in Switzerland.

This paper aims to identify the extent in which the interdepartmental conflicts from the local organizations can constitute a real barrier in assimilation of the concept of marketing in organizational practice in Romania. Based on an extensive literature review approach, which suggest different forms of conflicts between functional structures of an organization, and on a selective quantitative research, this article reveals the extent to which the assimilation of the concept of marketing in organizational practice in Romania may be hampered by their manifestation.

Water Alternating Gas (WAG) injection is a Enhanced Oil Recovery method spread in several countries around the world since fifty years ago approximately. The technique consists in to inject inside a reservoir alternates and successive slugs of water and gas to achieve a best sweep efficiency of the interest zone; this fact will be seen reflected in an increase of the recovery factor. A description of the main theoretical aspects of this EOR process is presented, as well as a state of the art taking into account factors such as dominant displacement mechanisms, used gases, type of objective rocks and geographical location of the projects. Important operational issues during technique implementation are discussed. Finally, a screening guide to apply this EOR process, keeping in mind gathered information of historical field cases, is showed.

The article presents a program of renovation works for buildings realized in the system W-70. The scope of work necessary to comply is analyzed and described with the specification of alternative materials and technology solutions. The analysis covers the building safety, thermal insulation, air exchange and ventilation, installation, visual and utility comfort. Special attention is paid to the work of improving microclimate in the rooms.

Vendor managed inventory has proven to be an effective tool for improving the supply chain performance by decreasing inventory-related costs and increasing customer service. It is quite evident from the literature that vendor managed inventory (VMI) has been successfully implemented in small and medium enterprises (SMEs). However, studies related to the implementation of VMI in Indian SMEs are very limited. Therefore, this study presents an empirical investigation of VMI practices in Indian SMEs using survey methodology. The paper evaluates the benefits, barriers, and effects of adopting VMI in Indian SMEs, and also investigates the IT tools and software used for VMI adoption. Furthermore, this study explores the dissimilarities among various sectors of SMEs adopting VMI. Based on the proposed methodology, it is found that organizational issues and unwillingness to share information are the major barriers. In terms of benefits, the major influencing variables are improved efficiency and improved channel relations.

Adolescents worldwide are at high risk for HIV, which makes them essential candidates for HIV vaccine trials. However, enrollment of adolescents into such trials has implications for trial sites. Adolescents are considered vulnerable subjects and require proxy consent in addition to their assent, which brings issues of confidentiality and access into play. HIV vaccine trial sites often do not have experience recruiting and retaining adolescents, and creating youth-friendly environments that are comfortable for guardians. This includes development of education materials that target both youth and their parents. Because these trials are of minimal individual benefit, sites will likely need to provide service in the form of health care and supportive structures to adolescents. Finally, a number of trial design options exist, and researchers will need to balance the risks and benefits of each, as for all issues surrounding the involvement of adolescents in HIV vaccine trials. [ABSTRACT FROM AUTHOR]

Directive 2001/42/EC of the European Parliament and of the Council of 27 June 2001 on the assessment of the effects of certain plans and programmes on the environment was officialised in July 2001. It establishes a basic framework for the assessment of the effects of certain plans and programmes on the environment, which should be adopted by the Member States of the European Union. In accordance with the principle of subsidiarity, the responsibility of developing a detailed procedure is left to the Member States.Within this context, this paper aims to assist the Member States with decisions concerning the implementation of a strategic environmental assessment (SEA) process conforming to the Directive by defining briefly some operational issues related to the Member State''s discretionary margin and by analysing their consequences regarding the objectives stated by the Directive (in terms of protection of the environment, contribution to the integration of environmental considerations into the preparation and adoption of plans and programmes, and contribution to more transparent decision-making). [Copyright &y& Elsevier]

Biomass with a large amount of moisture is well-suited to be processed by supercritical water gasification, SCWG. The precipitation of inorganics, together with char formation and re-polymerization, can cause reactor plugging and stop the process operations. When plugging occurs, sudden injections of relatively large mass quantities take place, influencing the mass flow dynamics significantly in the process. Reactor plugging is a phenomenon very well observed during SCWG of industrial feedstock, which hinders scale-up initiatives, and it is seldom studied with precision in the literature. The present study provides an accurate evaluation of continuous tubular reactor dynamics in the event of sudden injections of water. An interpretation of the results regarding water properties at supercritical conditions contributes to comprehending mass and heat transfer when plugging occurs. Experiments are then compared to SCWG of a biomass sample aiming to give key insights into heat transfer and fluid dynamics mechanisms that could help develop operational and control strategies to increase the reliability of SCWG. In addition, a simplified model is presented to assess the effect of material integrity on burst-event likelihood, which states that SCWG is safe to operate, at 250 bar and 610 °C, in tubular reactors made of 0.22 wall thickness-to-diameter ratio Inconel-625 with superficial microfractures smaller than 30 µm. We also suggest improvement opportunities for the safety of SCWG in continuous operation mode. [ABSTRACT FROM AUTHOR]

In Switzerland, deep geothermal energy can give a promising contribution to the future energy scenario. However, the expertise in operational issues of deep geothermal power plants is limited, and technical challenges, such as corrosion, are a determining factor for their reliable and long-term operation. In this work, two representative fluids of optimal geothermal conditions in Switzerland were studied. The corrosiveness of the solutions was assessed using two experimental setups that allow investigating the range of temperatures and pressures that apply to the reservoir and power plant conditions. The corrosion behaviour of API L80 steel was analyzed by means of electrochemical measurements (at 100 and 200 ∘ C ) and of gravimetric tests (at 100 ∘ C ). After the tests, the morphologies and composition of the corrosion products were obtained by scanning electron microscopy (SEM) coupled with energy dispersive X-Ray (EDX) and X-Ray diffraction (XRD). Results show that corrosion rates are significantly high at 100 ∘ C in environments with a chloride concentration of around 600 mg/L and pH around 7. The corrosion products deposited on the metal surface mainly consist of magnetite and/or hematite that might potentially form a protective layer. This study gives a first insight of the potential corrosiveness of geothermal fluids in Switzerland. [ABSTRACT FROM AUTHOR]

Vendor managed inventory has proven to be an effective tool for improving the supply chain performance by decreasing inventory-related costs and increasing customer service. It is quite evident from the literature that vendor managed inventory (VMI) has been successfully implemented in small and medium enterprises (SMEs). However, studies related to the implementation of VMI in Indian SMEs are very limited. Therefore, this study presents an empirical investigation of VMI practices in Indian SMEs using survey methodology. The paper evaluates the benefits, barriers, and effects of adopting VMI in Indian SMEs, and also investigates the IT tools and software used for VMI adoption. Furthermore, this study explores the dissimilarities among various sectors of SMEs adopting VMI. Based on the proposed methodology, it is found that organizational issues and unwillingness to share information are the major barriers. In terms of benefits, the major influencing variables are improved efficiency and improved channel relations. [ABSTRACT FROM AUTHOR]