bluuebunny/crossref_metadata_2025 huggingface dataset:
DEVELOPMENT OF HIGH EFFICIENT SHELL-AND-TUBE HEAT EXCHANGERS BASED ON PROFILED TUBES
Authors:   Institute of Engineering Termophysics of National Academy of Sciences of Ukraine, Ukraine, Chalaev Djamalutdin , Silnyagina Nina ,   Institute of Engineering Termophysics of National Academy of Sciences of Ukraine, Ukraine
Published: February 2021

The use of advanced heat transfer surfaces (corrugated tubes of various modifications) is an effective way to intensify the heat transfer and improve the hydraulic characteristics of tubular heat exchangers. The methods for evaluating the use of such surfaces as working elements in tubular heat exchangers have not been developed so far. The thermal and hydrodynamic processes occurring in the tubes with the developed surfaces were studied to evaluate the efficiency of heat exchange therein. Thin-walled corrugated flexible stainless steel tubes of various modifications were used in experimental studies. The researches were carried out on a laboratory stand, which was designed as a heat exchanger type "tube in tube" with a corrugated inner tube. The stand was equipped with sensors to measure the thermal hydraulic flow conditions. The comparative analysis of operation modes of the heat exchanger with a corrugated inner tube of various modifications and the heat exchanger with a smooth inner tube was performed according to the obtained data. Materials and methods. A convective component of the heat transfer coefficient of corrugated tube increased significantly at identical flow conditions comparing with a smooth tube. Increasing the heat transfer coefficient was in the range of 2.0 to 2.6, and increased with increasing Reynolds number. The increase in heat transfer of specified range outstripped the gain of hydraulic resistance caused by increase of the flow. Results and discussion. CFD model in the software ANSYS CFX 14.5 was adapted to estimate the effect of the tube geometry on the intensity of the heat transfer process. A two-dimensional axially symmetric computer model was used for the calculation. The model is based on Reynolds equation (Navier-Stokes equations for turbulent flow), the continuity equation and the energy equation supplemented by the conditions of uniqueness. SST-turbulence model was used for the solution of the equations. The problem was solved in the conjugate formulation, which allowed assessing the efficiency of heat exchange, depending on various parameters (coolant temperature, coolant velocity, pressure). The criteria dependences were obtained Nu = f (Re, Pr). Conclusions. The use a corrugated tube as a working element in tubular heat exchangers can improve the heat transfer coefficient of 2.0 - 2.6 times, with an increase in hydraulic resistance in the heat exchanger of 2 times (compared with the use of smooth tubes). The criteria dependences obtained on the basis of experimental studies and mathematical modeling allow developing a methodology for engineering calculations for the design of new efficient heat exchangers with corrugated tubes.
MODELS OF FUTURE MANAGERS PREPARATION TO THE APPLICATION OF PEDAGOGICAL MANAGEMENT TECHNOLOGIES
Authors:   Mukachevo State University, Ukraine, Shvardak Marianna
Published: February 2021

Subject of research: the system of preparation of future managers for the application of pedagogical management technologies. The survey used online survey, scaling and ranking methods. The purpose of the study: to outline the structural and functional model of the system of training future heads of general secondary education institutions to use the technologies of pedagogical management. the struc-tural-functional model of the system of preparation of future managers for the appli-cation of pedagogical management technologies is presented, the main structural blocks and the nature of their interaction are outlined. It was found that the target block of the presented model is system-forming, as it reflects the purpose and leading tasks of the system of training future managers, which serve as a basis for determining the content, organizational forms, methods and means of forming readiness to apply pedagogical management technologies. The methodological block, in turn, reveals a system of eponymous approaches and principles (general didactic and specific), which became the scientific basis for defining and implementing pedagogical conditions, structuring the content of the system of training future leaders to use pedagogical management technologies, optimal choice of forms, methods and teaching aids. activities. The content block is determined by the educational program, curricula, programs, textbooks, manuals, modern scientific concepts and methodological developments in pedagogical technologies, which are essential for the formation of the ability of future leaders to apply pedagogical management technologies. The procedural block is characterized by the integrity and systematization of the educational process in terms of master's degree, ensuring the participation of the applicant in all activities. Implemented through the use of training and diagnostic technologies in the training system. The control unit reproduces the achievement of the goal, ie the end result of the process of preparing the future leader for the application of pedagogical management technologies - the formation of this readiness. The proposed model corresponds to the identified trends in the coordination of changes in professional activities and the content of vocational education on the example of training future managers to use technologies of pedagogical management. The presented model can be considered as a basis of original strategy of professional education in the conditions of a magistracy, but at the same time, efficiency of its application needs to be checked in an experimental part of research for the further comprehension and adjustment.
Research and Prospect of Quality Development of Pharmaceutical Technology in Drug Research and Development
Authors: Zhang Bei , Ning Zongchao
Published: February 2021

Pharmaceutical technology is an indispensable and important link in drug research and development, which plays a key role in drug research and development quality. In the background of science and technology development, pharmaceutical technology has been greatly developed, but also to promote the quality of drug research and development, to provide more guarantee for people’s health. In the new era, how to achieve pharmaceutical technology innovation, so as to further improve the quality of drug research and development, is an important research topic in the current related industries. This paper mainly revolves around quality of pharmaceutical technology development of a series of exploration, in the traditional drug development based on a better control of drug quality, the future of smart pharmaceutical green pharmaceutical development direction, aims to further enhance the pharmaceutical technology, promote the quality of research and development to promote the comprehensive, promote the steady development of the pharmaceutical industry as a whole.
Representation of Political Culture of the Siberian Social Democrats in the Soviet Literature of the 1960-1980s
Authors: Isachkin Sergei Pavlovich
Published: February 2021

The article presents a survey of the Soviet literature of the 1960-1980s on political culture of representatives of the Siberian branch of the Russian Social Democratic Labour Party. Scientific originality of the study lies in the fact that the author for the first time provides a historiographical analysis of the problem. The paper reveals conditions, tendencies and problems of developing the Soviet historiography of regional social democratic organizations in the period before and during the First Russian Revolution. The conducted research allows concluding that in the mentioned period, the source base of the historical and political science was considerably enlarged, the number of scientific staff increased, new coordination centres appeared, but methodological basis remained the same, so conceptually new studies could hardly appear.
Design Strategy and Issues of Realising Tourism Cultural and Creative Products in Northeast China
Authors: Wei Xinxin , Zhang Yang
Published: February 2021

The purpose of the study is to elaborate a design strategy for cultural and creative products to be used in the tourism sector of the North-East of China. Scientific novelty of the work lies in identifying features of local culture of Northeast China, which can be used in a design strategy when developing tourism cultural and creative products. The result of the research amounts to elaborating a design strategy for cultural and creative products with a focus on cultural codes and images of regional culture of Northeast China. The authors determined opportunities of reinvigorating tourism business in northern provinces of the People’s Republic of China, which are provided by production of regionally oriented cultural and creative products.
Polemics of the 1830-1840s on Railway Transport Role in Russia’s Social and Economic Development
Authors: Kolpakov Petr Aleksandrovich
Published: February 2021

The paper reveals historical prerequisites for establishing railways in the Russian Empire in the XIX century. Scientific originality of the study lies in the fact that the author for the first time analyses the political elite’s views on the following issues: prospects for railway construction and potential influence of railways on the Russian economy and military potential. The findings indicate that railway transport wasn’t initially considered as a basis of economic and military development. The need for large-scale investments and doubts concerning efficiency of railways - such were the arguments of political figures who opposed establishment of railways in Russia in the reign of Nicholas I. The sovereign’s decision based on expert opinion and foreign experience promoted Russia’s development as a railway empire.
Scientific Provision of Activity of Komsomol Organizations and Agencies for Youth Affairs (the 1980-2000s)
Authors: Tkachenko Victor Viktorovich
Published: February 2021

The paper analyses organization of studies on youth problems in the 1980-2000s. The article reveals the role of Komsomol and agencies for youth affairs in studying youth problems, emphasizes relevance of this research area under the conditions of radical social transformations, justifies necessity of scientific approach to determining the basic trends in youth work. Scientific originality of the study lies in the fact that the author provides a comprehensive analysis of scientific provision of youth work, introduces previously unpublished archival documents into scientific circulation. The findings indicate that in the mentioned period, scientific provision of youth work was largely determined by socio-economic, political, administrative factors.
Modernity III (the Second Half of the ХХ Century) - Artwork Directions
Authors: Demchenko Aleksandr Ivanovich
Published: February 2021

Editor-in-Chief’s Column continues publication of a large series of artistic-historical essays which consecutively consider the major epochs. These reviews aim to outline the humanity’s evolution panorama through the lens of all the art forms resulting in ontological generalisation. Ancient World, Antiquity, Middle Ages, Renaissance, Baroque Epoch, Enlightenment, Romanticism, Post-Romanticism Epoch, Modernity I (Early ХХ Century) and Modernity II (Middle of the ХХ Century) were examined in previous essays.
Higher Historical Education at Ussuriysk State Pedagogical Institute (USPI) in the Soviet Period (1976-1991)
Authors: Karelova Elena Viktorovna , Zaitsev Roman Mikhailovich
Published: February 2021

The purpose of the study is to characterise higher historical education development at Ussuriysk State Pedagogical Institute (USPI) from 1976 to 1991. The article examines history of the USPI faculties that trained history teachers and presents the main areas of their activities. Scientific novelty of the work lies in the fact that it considers the process of higher historical education formation at the USPI using unpublished sources of the Municipal Public Institution “Archives of Ussuriysk City District”. As a result, the researchers have identified features of higher historical education development at the USPI, such as strong practical (pedagogical and local history) orientation, sequence of transformations.
Mycoflora and DNA sequencing analysis of radioresistant fungi isolated from irradiated vehicular air conditioning filters collected in São Paulo, Brazil
Authors:   Instituto de Pesquisas Energéticas e Nucleares (CETER- IPEN), Universidade de São Paulo, Aquino Simone , Alves de Lima José Eduardo ,   Laboratory Department, Universidade Nove de Julho, São Paulo, Alves dos Reis Tatiana ,   Microbiology Department, Instituto de Ciências Biomédicas II (ICB II-USP), Universidade de São Paulo, Correa Benedito ,   Microbiology Department, Instituto de Ciências Biomédicas II (ICB II-USP), Universidade de São Paulo, Borrely Sueli Ivone ,   Instituto de Pesquisas Energéticas e Nucleares (CETER- IPEN), Universidade de São Paulo
Published: February 2021

Fungal bioburdens in filters from car air conditioning systems represent a potential risk of respiratory or pulmonary diseases to both passengers and drivers. The present study demonstrated high fungal contamination in air conditioning filters collected from fifty-seven vehicles from the city of São Paulo, Brazil. The filters samples were irradiated with 10, 15 and 20 kGy gamma ray doses with a cobalt-60 source. The presence of Aspergillus flavus, Penicillium glabrum and Fusarium incarnatum-equiseti remaining after the ionizing treatment with 10 and 15 kGy. The radioresistant pathogenic species was confirmed through genetic sequencing of the ITS, β-tubulin and calmodulin gene rDNA regions. The 20 kGy dose was efficient in inhibiting pathogenic fungi growth in all samples but promoted the fungal decontamination in 79% of the samples. These results and other efforts will enable ionizing radiation to become an important tool in contributing to the recycling of automotive vehicle air filters and in ensuring indoor air quality for both drivers and passengers. Keywords: Fungal contamination, indoor air quality, vehicle air filters, ionizing radiation.
PENINGKATAN KUALITAS PELAYANAN DENGAN METODE SERVQUAL PADA PT. MEDIA PURNA ENGINEERING AREA PT. KRAKATAU STEEL (PERSERO) TBK
Authors: Sahrupi Sahrupi , Zulqornain Tb Asror
Published: February 2021

PT. Media Purna Engineering area PT. Krakatau Steel (Persero) Tbk atas pelayanan jasa perawatan mekanik rotating, sistem hidrolik, kontruksi, dan piping. Adapun metode penelitian yang digunakan adalah metode service quality (servqual) untuk mengukur tingkat kepuasan dan kualitas pelayanan yang diberikan. Pengumpulan data dilakukan dengan menyebarkan kuesioner kepada karyawan PT. Krakatau Steel (Persero) Tbk dan dengan melakukan observasi secara mendalam tentang pelayanan jasa yang diberikan oleh PT. Media Purna Engineering kepada PT. Krakatau Steel (Persero) Tbk. Berdasarkan hasil penelitian menunjukkan bahwa kualitas pelayanan jasa PT. Media Purna Engineering tergolong baik, namun masih ada 3 atribut kualitas pelayanan yang masih perlu ditingkatkan atau dikembangkan kembali dari 25 atribut kualitas pelayanan diantaranya adalah kelengkapan dan kesiapan perlengkapan kerja, kecepatan dalam memberikan solusi, pekerja mempunyai pengetahuan dan keterampilan yang diperlukan pekerjaan. Kualitas yang dirasakan oleh mitra memberikan dampak pada kelangsungan bisnis yang berkelanjutan. Saran yang diberikan dalam penelitian ini adalah PT. Media Purna Engineering diharapkan dapat meningkatkan kualitas sumber daya manusia yang ada dengan tujuan meningkatkan kualitas pelayanan yang diberikan baik dari kelengkapan dan kesiapan peralatan kerja, daya tanggap pekerja, kepedulian akan keluhan-keluahan, kecepatan dalam bertindak memberikan solusi, ketepatan waktu penyelesaian pekerjaan, kesesuaian hari dan jam kerja, serta kualitas pelayanan lainnya yang dianggap perlu ditingkatkan guna kepuasan mitra perusahaan untuk kelangsungan bisnis yang berkelanjutan.Kata Kunci : Kualitas Pelayanan, Service Quality (Servqual), Atribut Kualitas Pelayanan.
MATHEMATICAL REPRESENTATION ABILITY OF JUNIOR HIGH SCHOOL STUDENTS ON SURFACE AREA OF CUBE AND CUBOID
Authors: Gina Nurani Mardhiyatul , Jusniani Nia , Budiman Hedi
Published: February 2021

Students still have difficulty in solving contextual math problems. It is because students are not used to solving problems using diverse mathematical representations. The representation can make it easier for students to solve abstract math problems. This study aims to determine and identify the types of errors and factors made by students in mathematical representation ability test questions. This study's subjects were 20 students of class VIII-H at SMPN 1 Cugenang on the Surface Area of Cube and Cuboid. The method used is qualitative. The process of collecting data is observation, written test, interview. The results showed that the level of students' mathematical representation ability based on indicators: (1) was 41% on the indicator using visual representations to solve problems and make geometrical drawings to clarify problems and facilitate resolution, (2) by 64% on indicators of problem-solving by involving mathematical expressions, (3) 61% of indicators create problem situations based on data or representations given. Furthermore, based on the analysis of students' answers in tests on a matter of mathematical representation ability, students making mistakes that are data errors, using definitions or theorems, and technicalities. Factors causing students to make mistakes are forgetfulness, lack of accuracy, learning difficulties, family environment.
DEVELOPMENT OF E-LEARNING TEACHING MATERIALS ON MATRICES BASED ON COGNITIVE LOAD THEORY
Authors: Eliana Eliana , Nindiasari Hepsi , Santosa Cecep Anwar Hadi Firdos
Published: February 2021

Learning will be effective if it can minimize extraneous cognitive load because students' understanding can be improved and stored in long-term memory. The purpose of this study was to determine the development of e-learning teaching materials on matrices based on cognitive load theory that is valid, practical, and effective. The development of this teaching material uses e-LKS (electronic student worksheet) with the help of a liveworksheet and presents example-based learning. This study uses the ADDIE development model. The development steps used are (1) analysis, (2) design, (3) development, (4) implementation, (5) evaluation. Valid test based on expert judgment shows that e-learning teaching materials on matrices based on cognitive load theory get an average of 4.25 with very valid category so that this teaching material is feasible to use. The practicality test based on the student response questionnaire showed that this teaching material obtained an average of 79.7% with a good category, and the evaluation test showed that this teaching material obtained an average of 78.6% with student completeness in learning so it can be concluded that e-learning teaching materials on matrices based on cognitive load theory can be said to be effective.
Analysis of Local Government Studies and Development Administration in South Kalimantan
Authors: Franklin Rosalind
Published: February 2021

The State Civil Apparatus (ASN) is a vital subject in a country's governance and development system. ASN neutrality in politics is a must. In fact, ASN is often used as a political object from the power of political parties and actors not only at the national but also regional level. This study aims to describe the ASN's political position in the elections in Barito Kuala Regency. As a critical review to explore and build a new paradigm of looking at ASN's political position during the 2019 Legislative Election process in Barito Kuala Regency. A qualitative approach with descriptive methods is used in research. Data collection techniques through three steps, namely: observation, interviews, and documentation. Analysis of Miles and Hubermen's data models and triangulation techniques are used to see the validity of the data. The results of the study are described: (1) The Political Position of ASN in Barito Kuala Regency during the 2019 Legislative Election in some ASNs was still considered to be in favor of one of the legislative candidates. Cases of neutrality violations that occurred in several ASNs, put themselves in a neutral political position. The role of ASN in the formation and distribution of power is only in the voting booth, namely choosing one of the existing legislative candidates. (2) The political position of ASN in Barito Kuala Regency during the 2019 Legislative Election should be able to place itself in a neutral position in accordance with the appeal of the circular letter from MENPAN-RB and the applicable regulations. To build a new paradigm for ASN's political position, the perpetrators of ASN neutrality violations should be fostered because most do not understand their position. For ASN which shows partiality, the organizer (Bawaslu) should take action on this matter. Keywords: political position, civil servants, legislative elections.
The forest, the trees, or both? Hierarchy and interactions between gist and object processing during perception of real-world scenes
Authors: Furtak Marcin , Mudrik Liad , Bola Michał
Published: February 2021

The global-to-local theories of perception assume that the gist of a scene is computed early and automatically, whereas recognition of objects occurs at a later processing stage, requires attentional resources, and is primed by the representation of gist. To test these theoretical predictions, we investigated the processing hierarchy of gist- and object-recognition and their interaction in two experiments (total N = 60). Backward-masked images of real-world scenes were presented for a range of brief durations - between 8 ms and 100 ms, and participants performed either an object or a background classification task, in separate blocks. We report three main findings. First, scenes’ backgrounds were generally classified more accurately than foreground objects, but recognition of objects was boosted to the same level as backgrounds by cueing spatial attention to the exact object’s location. Second, backgrounds influence objects’ recognition, as objects presented within semantically incongruent backgrounds were classified less accurately. Third, objects influence background categorization, as backgrounds comprising incongruent objects were also classified less accurately. Therefore, the first two findings support the global-to-local theories, implying that gists are indeed more readily perceived than objects, probably at an earlier stage. Yet the latter finding that objects also influence gist recognition suggests a more parallel and interactive view of both processes than previously assumed.
Factors Influencing Investment in Mutual Fund Schemes of Nepal
Authors: Shrestha Dipesh Pote , Shrestha Yogesh Man
Published: February 2021

The history of mutual funds in Nepal began with the introduction of “NCM Mutual Fund 2050” in 1993. The Mutual Fund Regulation, 2010 has played an important role in development of Mutual funds as momentous progress can be observed after its implementation. The mutual fund sector has raised Rs. 17.49 billion through public offering and this figure is projected to reach Rs. 19.79 billion by the end of FY 2019/20. Considering the momentous growth in the mutual fund industry this study attempts to analyse the investment pattern of Nepalese mutual fund Investors based on various parameters. This study also attempts to identify the critical factors influencing investment in mutual fund schemes of Nepal. The results indicate that the investors are moderately averse to mutual fund schemes. The results further show that the investors chose mutual fund schemes, being relied on key performance indicators of Mutual funds and their perception towards several aspects of mutual fund schemes. Moreover, fund managers’ qualities and corporate governance factors are considered important though the results are not statistically significant.
Diaspora and Cultural Identity: A Conceptual Review
Authors: Bhandari Nagendra Bahadur
Published: February 2021

The theorists vary in their conceptualizations of diaspora and cultural identity of immigrants. Broadly speaking, the theorizations of diaspora can be categorized into four different groups with their focus on diverse aspects of immigrants’ lives. The first classical phase describes the forced migration of immigrants including victimhood diaspora of Jewish, Africans and Armenians. The second conceptualization incorporates historical, cultural and social diversities of people living in the diaspora. Critiquing the second phase, the third group of theorists deconstructs bipolar notions of the home and host country, and celebrates the inconsistencies, and fluidities of immigrants’ identities in diasporic third space. In contrast, the fourth conceptualizations emphasizes on relevance of the origin and historical exploitation of people of poor countries. Both the historical experiences and present negotiations play decisive roles in the formation of cultural identity of immigrants.  The present article briefly reviews different conceptualizations of the diaspora and cultural identity of immigrants.
Ludzie w zawieszeniu (Siergiej Lebiediew, Dzieci Kronosa)
Authors: Zywert Aleksandra
Published: February 2021

In the novel The Goose Fritz, Sergei Lebedev puts the spotlight on the still-relevant problem of the history of Russian Germans, a question which adds depth to discussion about the complex past of the country. Russian Germans, as the author portrays them, live in a state of suspension, bearing a mark of foreignness in both Russia and Germany. Functioning almost from the very beginning between two totalitarian regimes (tsarist and then Soviet regimes on one side, and on the other, fascism), each of which forces people to divest themselves of their own past in favor of an identity aligned with the more “correct” politics of the time and place, Russian Germans have lost the memory of generations and remain “an uprooted people”. In this context, Lebedev’s story concerns human nature as such, as well as a problem of great importance for contemporary Russia: the status of the German minority and the prospect of their migration to Germany.
Поколение заката СССР в романе Алексея Никитина Victory Park
Authors: Bortnowski Antoni
Published: February 2021

The subject of this article is the presentation of Soviet reality in Alexei nikitin’s novel, Victory Park. The Russian-speaking Ukrainian writer presents in this work a wide panorama of the life of the inhabitants of left-bank kiev in the first half of the 1980s. The generation of the late Stagnation Period lives in a world of discre- dited ideas, omnipresent absurdity, and hypocrisy. The aim of the article is to try to locate the sources of widespread apathy and hopelessness in nikitin’s novels, which, to a large extent, shape the young generation trying to find their way in a stagnant reality. The key to understanding the life attitudes of the protagonists is the analysis of the specificity of kiev reality, which is the dominant feature of the world presented in the Victory Park.
Ecological trial of the rostov rice varieties in the Krasnodar territory
Authors: Kostylev P. I. , Ladatko М. А. , Krasnova Е. V. , Zeleneva I. A. , Foliyants B. V. , Aksenov А. V.
Published: February 2021

In modern rice growing, the development of new varieties and their rapid introduction into agricultural production is of great importance. Every year the Federal Research Center of Rice and the ARC “Donskoy” develop more productive rice varieties with improved tolerance to unfavorable biotic, abiotic stress factors, with various nutritional qualities of seeds. Any variety responds differently to a variety of agro-ecological conditions, forming different productivity, as the main indicator of cost and demand in production. The current paper has presented the results of ecological variety testing of four rice varieties conducted in 2020 on the fields of ‘Krasnoarmeisky’ and ‘Krasnaya’ located in the Krasnoarmeisky district of the Krasnodar Territory. Each variety was identified on variability of productivity and number of plants per unit area. The productivity of rice varieties varied significantly depending on the variant of the trial (2.93–8.79 t/ha). The variety ‘Kapitan’ significantly surpassed the standard variety ‘Rapan’, when sown after rice and alfalfa, but was at the same level in the agro-ameliorative field. The variety ‘Kapitan’ when sown after ‘AMP’ (high check) formed the maximum productivity of 8.79 t/ha in the background variant and 8.66 t/ha when topdressing with N30. It was due to the high resistance of the variety ‘Kapitan’ to local species of blast in difference from other varieties. Rice stand ranged from 70.5 to 519.0 pcs/m2. The variability between the varieties within the variant was medium (CV = 11.1–19.2%), and between the experimental variants it was high (CV = 59.0–71.3%). For cultivation in the Krasnodar Territory there has been recommended the rice variety ‘Kapitan’, developed by the ARC “Donskoy” together with FRC of rice, which has shown fairly high productivity with little variability.
The efficiency of the herbicide ‘Ballerina’ on grain sorghum
Authors: Metlina G. V. , Vasilchenko S. A.
Published: February 2021

The current paper has presented the study results of the effect of different dosages of the herbicide ‘Ballerina SE’ on the weediness of sorghum sowing, as well as the economic efficiency of the application. The purpose of the study was to estimate the efficiency of the use of the herbicide ‘Ballerina’ on grain sorghum and its effect on the weediness of the sowing and the amount of productivity. The field trials were carried out in 2017–2019 in the laboratory for cultivation technology of row crops of the FSBSI Agricultural Research Center “Donskoy” (Zernograd). The experimental plot is located in the southern agricultural zone of the Rostov region (with insufficient and unstable moisture). The soil of the experimental plot was ordinary heavy loamy blackearth (chernozem) on forestry loams, with 3.2% of humus, 18.5–20.0 mg of P2O5 and 342–360 mg of K2O per kg of soil. The hydrothermal coefficient during the years of study ranged from 0.32 to 0.89, which characterized the insufficient moisture supply of the growing season. There was presented the information on the varietal composition of grain sorghum in the southern zone of the Rostov region. The applied dosages of the herbicide had a significant effect on the reduction of the weediness of grain sorghum after their application (the decrease ranged from 78.3 to 96.7%). The greatest decrease in weediness was noted for dicotyledonous weeds. When using 0.5–l of the herbicide ‘Ballerina SE’ per ha, there was obtained the highest conditional net income of 22,230 rubles/ha, with the lowest production cost of 4,329 rubles/ha and the highest profitability level of 163%.
Innovative Base Die Debug Technique with TSV Wirebond for 3D Stack-Die Devices
Authors: Chuang Wen-Hsien , Tong Tom , Oh May Ling , Ryu Hyuk Ju , Xu Di , Kumar Swaran , Zhao Shuai , Huening Jennifer , Chen Chia-Yi , Ladwig Charles W , Foster Joshua D , Badger Lacey
Published: February 2021

With the 3D stack-die technology, top die and base die are stacked together with micro-bumps for die-to-die interconnection and a through silicon via (TSV) for die-to-package connection. This technology provides tremendous flexibility as designers seek to "mix and match" technology IP blocks with various memory and I/O elements in novel device form factors. Even though the lock-in thermal detection technique had been demonstrated as a useful debug technique to detect defects on packages or pin related fails on 3D stack-die configuration, it is difficult to apply this technique to do functional debug. This paper presents a novel base die debug technique with TSV wirebond for 3D stack-die devices. A comprehensive study on the base die debug flow with real failing cases is also presented. Base die debug techniques will need to continue to be innovated to provide complete debug solutions for such platform.
Fault Isolation of Resistive/Open 3-D Wafer Bonding Interconnects by Thermal Laser Stimulation and Light-Induced Capacitance Alteration
Authors: Jacobs K.J.P. , Kim S.W. , De Wolf I. , Beyne E.
Published: February 2021

This paper presents novel optical beam-based defect localization approaches for resistive and open failed wafer-towafer (W2W) bonding interconnects for 3-D integration. The use of an etch back process in combination with thermal laser stimulation (TLS) and light-induced capacitance alteration (LICA) using visible laser excitation enables us to accurately pinpoint defects in high-density W2W interconnect structures down to a pitch of 2.2 µm. We confirm our results by focusedion beam (FIB) cross sectioning.
Addressing Failures in Advanced Packaging Through a Correlative Workflow
Authors: Leslie Neel , Lai Brian , Lee Heebeom , Lee Mingi , Kang Christopher H. , Patakova Zuzana , Zelenka Frantisek , Varslot Trond
Published: February 2021

Correlation across applications and imaging platforms is essential and brings increased insurance for fault isolation in advance of destructive imaging. This paper demonstrates an approach for a detailed advanced packaging defect isolation and analysis workflow. To determine the effectiveness of the proposed workflow, a 28nm flip-chip was used as a test vehicle. By using this workflow, the yield in determining the fault location has increased from 60% to over 85%. To further improve the result, a surface charging mitigation scheme was used and the resulting measured correlative offset between the two systems was found to be less than 10um. This creates novel opportunities in reducing the size of the cross-section and increasing the overall throughput to find the defect, with high confidence. This workflow creates unique abilities in fault localization and analysis as it can detect both opens and shorts between the different techniques that are employed.
Laser Ablation for Throughput Increase in Large Volume Semiconductor Failure Analysis Tasks
Authors: Tuček Marek , Búran Martin , Váňa Rostislav , Hladík Lukáš , Oboňa Jozef Vincenc
Published: February 2021

As the semiconductor industry demands higher throughput for failure analysis, there is a constant need to rapidly speed up the sample preparation workflows. Here we present extended capabilities of the standard Xe plasma Focused Ion Beam failure analysis workflows by implementing a standalone laser ablation tool. Time-to-sample advantages of such workflow is shown on four distinct applications: cross-sectioning of a large solder ball, cross-sectioning of a deeply buried wire bond, cross-sectioning of the device layer of an OLED display, and removing the MEMS silicon cap to access underlying structures. In all of these workflows we have shown significant decrease in required process time while altogether avoiding the disadvantages of corresponding mechanical and chemical methods.
Knowledge-Based Object Localization in Scanning Electron Microscopy Images for Hardware Assurance
Authors: Lu Hangwei , Wilson Ronald , Vashistha Nidish , Asadizanjani Navid , Tehranipoor Mark , Woodard Damon L.
Published: February 2021

Object localization is an essential step in image-based hardware assurance applications to navigate the view to the target location. Existing localization methods are well-developed for applications in many other research fields; however, limited study has been conducted to explore an accurate yet efficient solution in hardware assurance domain. To this end, this paper discusses the challenges of leveraging existing object localization methods from three aspects using the example scenario of IC Trojan detection and proposes a novel knowledge-based object localization method. The proposed method is inspired by the 2D string search algorithm; it also couples a mask window to preserve target topology, which enables multi-target localization. Evaluations are conducted on 61 test cases from five images of three node-technologies. The results validate the accuracy, time-efficiency, and the generalizability of the proposed method of locating multi-target from SEM images for hardware assurance applications.
Word Line Defect Localization Methods in 2D NAND Flash
Authors: Chang Chung-Huan , Hsu Pei-Ning , Chung Yu-Min , Lian Nan-Tzu , Yang Ta-Hone , Chen Kuang-Chao , Lu Chih-Yuan
Published: February 2021

In this work, two analysis methods for word line (WL) defect localization in NAND flash memory array are presented. One is to use the Emission Microscope (EMMI) and Optical Beam Induced Resistance Change (OBIRCH) to analyze the device through backside, which has no risk of damage during sample preparation. Depending on the I-V characteristics of defects, different analysis tools can be applied. The second method is to analyze a device defect location that is hard to detect through backside analysis. The precise defect site can be localized by Electron Beam Induce Resistance Change (EBIRCH) [1,2], and the defect profile can be observed. The large memory array in NAND flash structure leads to the wide sample movement during EBIRCH analysis. The sub-stage movement function used successfully solves this problem.
Efficient Identification of Wafer Edge’s Defect with Volume Diagnosis Analysis and Plasma-FIB Planar Deprocessing
Authors: Song Hoseok , Kang Dong Hae , Park Jaeseok , Choi Jeongun , Cho Seongjun
Published: February 2021

In the failure analysis (FA) of modern semiconductor logic device manufactured in foundry fab, efficient identification of wafer edge’s defect was studied by using volume diagnosis analysis and plasma-focused ion beam (FIB) planar deprocessing. As the chip from wafer edge has multiple defective locations, there is the limitation of the conventional FA work to identify them. Here, we used volume diagnosis analysis to identify the multiple defective locations within chip and plasma-FIB planar deprocessing to delayer those locations and find out defects. The actual FA work verified that new workflow successfully identified the different defects from different layers from the chip of wafer edge and efficiently accelerated the quantity of FA results, importantly leading to more representative status of inline defect.
Addressing Failure Analysis Challenges in Advanced Packages and MEMS using a Novel Phase and Darkfield X-Ray Imaging System
Authors: Lau S.H. , Gul Sheraz , Zan Guibin , Vine David , Lewis Sylvia , Yun Wenbing
Published: February 2021

Currently gaps in non-destructive 2D and 3D imaging in PFA for advanced packages and MEMS exist due to lack of resolution to resolve sub-micron defects and the lack of contrast to image defects within the low Z materials. These low Z defects in advanced packages include sidewall delamination between Si die and underfill, bulk cracks in the underfill, in organic substrates, Redistribution Layer, RDL; Si die cracks; voids within the underfill and in the epoxy. Similarly, failure modes in MEMS are often within low Z materials, such as Si and polymers. Many of these are a result of mechanical shock resulting in cracks in structures, packaging fractures, die adhesion issues or particles movements into critical locations. Most of these categories of defects cannot be detected non-destructively by existing techniques such as C-SAM or microCT (micro x-ray computed tomography) and XRM (X-ray microscope). We describe a novel lab-based X-ray Phase contrast and Dark-field/Scattering Contrast system with the potential to resolve these types of defects. This novel X-ray microscopy has spatial resolution of 0.5 um in absorption contrast and with the added capability of Talbot interferometry to resolve failure issues which are related to defects within organic and low Z components.
Cutting-Edge Sample Preparation from FIB to Ar Concentrated Ion Beam Milling of Advanced Semiconductor Devices
Authors: Bonifacio C.S. , Nowakowski P. , Li R. , Ray M.L. , Fischione P.E. , Downing C.
Published: February 2021

Fast and accurate examination from the bulk to the specific area of the defect in advanced semiconductor devices is critical in failure analysis. This work presents the use of Ar ion milling methods in combination with Ga focused ion beam (FIB) milling as a cutting-edge sample preparation technique from the bulk to specific areas by FIB lift-out without sample-preparation-induced artifacts. The result is an accurately delayered sample from which electron-transparent TEM specimens of less than 15 nm are obtained.
A Solution for Obtaining an Advanced Lamella Geometry on the Grid with a Single Manipulation Step
Authors: Šikula Marek , Denisyuk Andrey , Hladík Lukáš , Oboňa Jozef Vincenc
Published: February 2021

A protocol for obtaining an advanced TEM lamella geometry using FIB-SEM is presented. Lamella lift-out procedure might require multiple manipulation steps or even breaking the vacuum in order to reach inverted or plan-view lamella geometries. We have developed a setup which enables lamella transfer from a bulk sample onto a TEM grid within a single, very simple manipulation step, with no need to break the vacuum or unload the sample. Most importantly, this approach does not require any additional devices to be installed.
Color Normalization for Robust Automatic Bill of Materials Generation and Visual Inspection of PCBs
Authors: Paradis Olivia P. , Jessurun Nathan T. , Tehranipoor Mark , Asadizanjani Navid
Published: February 2021

A Bill of Materials (BoM) is the list of all components present on a Printed Circuit Board (PCB). BoMs are useful for multiple forms of failure analysis and hardware assurance. In this paper, we build upon previous work and present an updated framework to automatically extract a BoM from optical images of PCBs in order to keep up to date with technological advancements. This is accomplished by revising the framework to emphasize the role of machine learning and by incorporating domain knowledge of PCB design and hardware Trojans. For accurate machine learning methods, it is critical that the input PCB images are normalized. Hence, we explore the effect of imaging conditions (e.g. camera type, lighting intensity, and lighting color) on component classification, before and after color correction. This is accomplished by collecting PCB images under a variety of imaging conditions and conducting a linear discriminant analysis before and after color checker profile correction, a method commonly used in photography. This paper shows color correction can effectively reduce the intraclass variance of different PCB components, which results in a higher component classification accuracy. This is extremely desirable for machine learning methods, as increased prior knowledge can decrease the number of ground truth images necessary for training. Finally, we detail the future work for data normalization for more accurate automatic BoM extraction. Index Terms – automatic visual inspection; PCB reverse engineering; PCB competitor analysis; hardware assurance; bill of materials
Influence of Alkaline Cleaning on Reliability of Stacked Copper Micro-Via
Authors: Yu Yeonseop , Ha Job , Lee HyoungRok , Lee Joohyung , Cho Kang-Young , Jeon Jongmyeong
Published: February 2021

Fan Out - Panel Level Packaging (FO-PLP) has redistribution layers (RDLs) which connect IC to a substrate. And each layer in the RDLs is connected through copper micro-vias. Viarelated defects including via separation are very critical because they can escape from electrical test and be found in the field. So many cleaning methods have been developed to keep the target pad surface free of oxides or organic contamination before forming vias. In this paper, we present a via separation case caused by alkaline cleaning introduced before seed metal deposition for electroplating of copper. We investigated the cause by analyzing the microstructure and chemical composition using a focused ion beam (FIB) and a transmission electron microscope (TEM) equipped with an energy dispersive spectrometer (EDS). Via separation, interestingly occurred at the interface between the seed Ti and the seed Cu not the interface between the seed Ti and the target pad..Cu surface which is known to be weak. We suggest a mechanism that structural imperfections at the outer rim of via bottom and galvanic couple of titanium and copper are involved in the separation of vias. Since two dissimilar metals of Ti and Cu are in direct contact, galvanic corrosion can occur in the presence of alkaline solution and discontinuities in the seed Ti layer. We found that galvanic corrosion in the studied system can be further complicated by the existence of copper oxide and titanium oxide as well as Cu and Ti.
Unlocking Novel FA Case Studies Using a Lock-in Amplifier
Authors: Lee Sukho , van Veenhuizen Marc , Navaretti Paolo , Donati Gaia
Published: February 2021

Lock-in techniques enable the detection of very small signals in a background that can be dominated by noise. This strength makes these techniques valuable especially for failure analysis of active devices where the deviation may be difficult to detect. This paper describes novel use case applications in which the lock-in amplifier plays a key role. The case studies covered are multi-frequency mapping fault isolation with nonperiodic patterns and frequency resonance measurement of a micro electro-mechanical system (MEMS) gyroscope. The paper presents how lock-in amplifiers enable digital failure analysis using compressed scan patterns. It reports on using a lock-in to characterize a MEMS gyroscope and on how to directly observe the gyroscope motion using phase laser voltage imaging/electro-optical frequency mapping. It can be concluded that the lock-in techniques form an essential part of the failure analysis toolkit and will only be more so with this study.
Ga Aggregation in Cu Layer on In-situ TEM Analysis: Observation and Alternative Solutions
Authors: Kim Seo-Jin , Park Byung-Kyu , Kang Christopher H.
Published: February 2021

In semiconductor manufacturing technology, copper has been widely used for BEOL process due to better conductivity than aluminum. TEM (Transmission Electron Microscopy) characterization has been played in key role to understand the process of semiconductor manufacturing. Gallium base Focused Ion Beam (FIB) is widely used on TEM sample preparation. The experiment to understand the impact of gallium which is from sample preparation process on Cu layer was performed. In-situ TEM studies have shown real time material characteristic of Cu at various temperature [1]. We observed the gallium aggregation phenomenon on Cu layer at round the temperature of 400°C. This thermal aggregation of gallium on Cu layer has been confirmed by EDS analysis in the study. Detectable amount of gallium was found in whole area in the sample before heating the sample at in-situ TEM work. This paper also introduces alternative solutions to resolve this gallium aggregation in copper layer including the sample preparation technique using Xe Plasma Focused Ion Beam (PFIB) [2]. This Xe PFIB showed the substantial improvement of specimen quality for the in-situ TEM experiment of sample preparation.