bluuebunny/crossref_metadata_2025 huggingface dataset:
Trayectoria normativa de la inteligencia artificial en los países de Latinoamérica con un marco jurídico para la protección de datos: límites y posibilidades de las políticas integradoras
Authors: Veronese Alexandre , Nunes Lopes Espiñeira Lemos Amanda
Published: August 2021

Muchos países de Latinoamérica están invirtiendo en planes o estrategias de inteligencia artificial (IA) y focalizan en la mejora del desarrollo económico. Una de las características fundamentales de las políticas públicas es el marco regulatorio. Además de las ya ampliamente mencionadas guías éticas, se pueden explorar otras trayectorias normativas como la legislación para la protección de los datos personales y los incentivos económicos. El artículo describe las políticas públicas para la IA de los países de la región que tienen sistemas jurídicos de protección de datos. Utiliza un método cualitativo para evaluar las políticas y estrategias de IA en Argentina, Uruguay, Colombia, México, Chile y Brasil, mediante la descripción de las posibilidades regulatorias en lo relacionado con el uso de la protección de datos. Luego de esta descripción, este estudio abre un debate acerca de los límites y problemas con la utilización de la protección de datos para regular a la IA. Concluye que los países no ofrecen muchas alternativas para evaluar a las inversiones tecnológicas como una posibilidad normativa, aun cuando todos los otros medios confíen en ellos para ser efectivos. También, establece que estas inversiones deben tener en cuenta a la dimensión del valor social para beneficiar realmente a los países.
Badminton Smash Basic Training Model
Authors: Rahmat Ade
Published: August 2021

The  purpose  of  the study. This study aims to develop a basic training model for badminton Smash in badminton athletes in West Kalimantan.
Materials and methods. The method used in this study is research and development modifying the Brog and Gal model.
Results. The results of this study indicate that the badminton smash basic training model can be said to be valid from the study and assessment by experts.
Conclusions. And the development of basic badminton smash training model is categorized as feasible to be used in badminton smash training because the developed smash model can be a smash training model that requires hand skills and strength, so the Badminton Smash Basic Training Model is recommended as a training model that can provide new nuances in apply a good smash.
Usulan Perbaikan Metode Kerja Berdasarkan Micromotion Study Pada CV. X
Authors: Bahri Syamsul , Syarifuddin Syarifuddin , Muhammad Muhammad , Hasanah Metri
Published: August 2021

CV. X yang merupakan suatu perusahaan pembuatan aneka macam mebel seperti pintu, jendela, kusen, meja, dan kursi. CV. X ini bertempat di Jl. Medan-Banda Aceh, Blang Panyang, Lhokseumawe.Penelitian ini dilakukan pada setiap stasiun kerja pembuatan pintu karena dari permasalahan tersebut berdampak pada efesiensi dan efektifitas pekerjaan.Pada stasiun kerja ini masih terdapatnya gerakan-gerakan yang tidak diperlukan yang dilakukan oleh operator pada saat melakukan pekerjaannya.Sehingga ada waktu yang terbuang untuk hal yang tidak diperlukan yang menyebabkan adanya pemborosan waktu yang menyebabkan tidak efektifnya suatu pekerjaan.Penelitian ini bertujuan untuk perbaikan gerakan-gerakan yang kurang efektif dalam melakukan suatu pekerjaan. Dilakukan pengamatan selama proses perakitan berlangsung, Pada kondisi kerja awal, waktu standar awal mencapai 10.908,45 detik atau 181,8 menit, sedangkan pada kondisi kerja usulan mencapai 9.610 detik atau 160,2 menit, Sehingga dengan mengurangi gerakan yang kurang efektif dapat menghemat waktu selama 1.296 detik atau 21,6 menit dalam satu pintu.
Analisis Sistem Perawatan Mesin Boiler pada Industri Kelapa Sawit
Authors: Polewangi Yudi Daeng
Published: August 2021

Boiler adalah bejana tertutup yang terbuat dari baja yang memiliki fungsi untuk menghasilkan uap dan digunakan untuk pemanas, penggerak turbin dan sebagainya. Pemakaian dan perawatan boiler yang baik akan membuat efisiensi boiler semakin tinggi dan menghemat biaya operasional secara umum. Kondisi boiler pada salah satu industri kelapa sawit yang diteliti mengalami penurunan kinerja dan apabila tidak diperbaikikomdisi tersebut, maka mesin akan mengalami kerusakan yang akan menyebabkan kerugian waktu operasi (downtime). Permasalahan yang akan muncul akibat terjadinya downtime adalah keterlambatan produksi, hilangnya waktu efektif untuk berproduksi sehingga mempengaruhi produktivitas perusahaan. Hasil penelitian menunjukkan nilai availability ratio terendah terjadi pada bulan September 2018, hal ini disebabkan karena total downtime yang tinggi selama 4610 menit dikarenakan terjadi trouble dan waktu tunggu selama 1920 menit untuk recovery. Performance efficiency ratio jumlah bahan bakar yang digunakan tinggi yaitu sebesar 35 Kg/cm3 dikarenakan untuk recovery dari awal. Rate of quality mesin menunjukkan hasil yang bagus, hal ini dikarenakan tidak adanya reject yang terjadi
Covariant Factors of Activity-Oriented Curriculum Operation in Cooperative Learning Effectiveness
Authors: Chiang Shyh-Bao
Published: August 2021

The purpose of this study is to explore the operation of an activity-oriented curriculum. Class members were grouped by their majors to complete an academic seminar together and fill in the evaluation for the two variables of cooperative learning and participation attitude, so that this study could explore the relationship between covariate factors for cooperative learning effectiveness. The subjects of this study are the master students in the Department of Visual Communication Design of a university of science and technology in central Taiwan. The course is a required course seminar. In order to properly arrange the manpower, the nominal variables in research design were formed by grouping through professional division of labor. The research tools include cooperative learning evaluation and participation attitude evaluation. The data were obtained through the questionnaire about the two variables. The two-factor covariate analysis was used to test the hypothesis. The results showed that the cooperative learning effectiveness did not vary according to the grouping type when the co-variable interference of participation attitude was excluded. It was found that the academic group had the best evaluation among all groups. Therefore, it was concluded that the students in the master class, due to their mature mental development, were generally able to put themselves in the membership’s position and pay attention to team efficiency in the learning environment of team cooperation, so as to gather the centripetal force from the group to the whole class, and jointly complete the task assigned by the course. Among the groups, the academic group had few members but heavy works. Due to proper division of labor, they completed the task on time, and the experience of being responsible for the administrative processing of the academic paper was profound, which led to the best evaluation of the cooperative learning effectiveness. Due to limited number of members, this study also received many suggestions during the review meetings, which aided in facilitating successful implementations of the subsequent course activities and enabling students to gain practical experiences from this activity.
Leading in Higher Education with Emotional Competence
Authors: Beytekin Osman Ferda
Published: August 2021

The aim of this interpretative study was to find out how higher education administrators thought about emotional competence and what emotional competence ideas and skills they thought were essential for success. Specifically, the aim of this study was to get a better understanding of how administrators in departments of higher education may use their emotional skills to their benefit in their professions. In-depth interviewing takes one step further by focusing in considerable detail on the life experiences and social behavior of selected individual respondents in qualitative research. An in-depth interview was conducted for this qualitative research with eight experienced heads of departments who shared their experiences for a number of reasons. In order to get meaning from the narratives, certain techniques and templates were used. Purposive sampling was used in the 2019-2020 academic year for eight heads of departments at a public university in Izmir, Turkey, with an emphasis on phenomena relevant to the topic and at least four years of administration experience in selecting criteria. The key insight from the study's findings is that participants interpreted emotional competence to entail the ability for university administrators to develop connections by generating trust in order to lead their department. Having an open mind, having an optimistic attitude, being respectful, being inclusive, listening actively were all regarded as key subthemes by higher education administrators. Longitudinal or mixed methods studies, as well as demographic variations in leaders' use of emotional competencies, might be explored in future research.
Transformation of Higher Education into New Normal
Authors: Beytekin Osman Ferda
Published: August 2021

The purpose of this qualitative study was to get a better understanding of faculty members' views on the future of higher education by their first-time online teaching experiences during the Fall 2021 academic semester, which was impacted by the COVID-19 pandemic. Due to the outbreak's rapid and widespread dissemination, it created a unique phenomenon that had a significant impact on faculty members who had no prior experience teaching courses entirely online. In order to conduct this qualitative research, purposive sampling was used to choose ten faculty members from a variety of disciplines who had at least ten years of experience teaching in a traditional classroom setting at a public university in Izmir, Turkey. Faculty members were asked about the future of higher education in the aftermath of the COVID-19 pandemic. Apart from that, each faculty member was asked to discuss how the mandatory shift to online education altered their teaching style and how institutional help impacted their experiences throughout the pandemic. As a consequence of their observations and statements of their perspectives on events they witnessed and personally experienced, the key issue of "transformation of higher education with hybrid perspective" developed as a central theme. The data analysis revealed the following subthemes: "educators on the internet," "sustain and evolve," and "university support". These findings may be applied in a variety of contexts, including educational leadership and the design of hybrid and online courses, among other applications in higher education.
Healthcare Managers’ Perception About the Sustainable Development Goals (SDGs)
Authors: Schwartzman Jonas A. S. , Zucchi Paola
Published: August 2021

In 2015, about 190 United Nations Member States proposed an ambitious agenda, to be worked on by different actors in society, which was entitled 2030 Agenda. The document was divided into 17 Sustainable Development Goals (SDGs), which are broken down into 169 targets aiming to eradicate poverty and promote a decent life for all. This study aimed to evaluate the perception of healthcare managers about SDGs, especially SDG 3, which addresses Good Health and Well-Being. This cross-sectional observational study identified and analyzed the participants’ profiles through online forms with questions about the general perception of the SDGs, and questions related to SDG 3. The quantitative analysis of the results was performed, in percentage terms, and the qualitative analysis was performed using the five-point Likert scale. Twenty-one technical directors of healthcare services participated in the survey. According to the results, 14 (66.6) of the participants presented medium to high knowledge regarding SDG. In addition, 18 (85.7%) of these professionals understand that the SDGs are of high/very high importance to guide public policies. In general, there is a low expectation for the achievement of the 17 SDGs in Brazil, but it was highlighted that it should be a priority, which SDG could contribute to the achievement of SDG 3: Good Health and well-being as well as the vision of policy recommendations to achieve the SDG 3 targets. This analysis allows contact with SDG and enables a deeper discussion on the topic in healthcare services.
Evaluating Elements of Demand-Side Policy Imperatives for Biogas from Waste Scheme Diffusion in the UK
Authors: Acharya Abhijeet , Cave Lisa A.
Published: August 2021

Over the last decade, demand-side policies are increasingly implemented to correct market failures and overcome the systemic problem in complex social-technical systems such as energy transition. This paradigm shift in policy approach results from realizing that relying solely on supply-side policy instruments to push innovative solutions into the market is insufficient. As part of the energy transition, many developed countries have considered Biogas from Waste (BfW) based on the Anaerobic Digestion (AD) process as a realistic renewable energy source and aim to create social, economic, and environmental benefits for their communities. Despite several policy instruments in the UK over the last ten years, the growth of BfW schemes remains subdued and faces market failures. This paper aims to evaluate elements of demand-side policies focused on addressing market failures to increase the diffusion of BfW schemes in the UK. We discussed effective demand-side policies related to the biogas sector in other European countries like Sweden, Denmark, and Italy. In the analysis, we observed UK’s policy instruments do not effectively address market externalities in the biogas sector. We also observed the biomethane market share in the UK is minimal; there is no market policy for green gas labeling towards demand articulation. The paper also made recommendations for policymakers in the UK to address market failures by proposing a push-pull policy model that combines demand-side policy interventions with supply-side policies.
A construção do olhar do turista: uma análise iconográfica a partir da revista a estrada de rodagem (1922 - 1923)
Authors: Silva Vania , Allis Thiago
Published: August 2021

Objetivo do estudo: Entender o papel da imprensa especializada no desenvolvimento do turismo, particularmente quanto à emergência do rodoviarismo no início do século XX no estado de São Paulo.Metodologia/abordagem: Investigação iconográfica, composta por análise iconográfica e interpretação iconológica (Kossoy, 2009) de imagens e textos sobre turismo, e de seu contexto, presentes na revista “A Estrada de Rodagem” (1922-1923), órgão de propaganda da Associação de Estradas de Rodagem (AER). Para embasar a interpretação iconológica, foram utilizados conceitos quanto à construção do olhar do turista (Urry Larsen, 2011), especialmente às viagens imaginativas. Também estão presentes os referenciais que ajudam a conhecer o contexto de construção de estradas do início do século XX, período que propiciou a criação da Revista.Originalidade/Relevância: A análise de imagens da imprensa com a metodologia de Kossoy (2009) é inédita nos estudos relativos à história do turismo. Compreender o papel do turismo no processo mostra sua relevância na própria criação e consolidação de culturas rodoviárias emergentes, que, como o estudo mostra, tiveram nas narrativas (proto)turísticas parte de seu argumento.Principais resultados: Identificaram-se aspectos que, de alguma forma, ajudaram a difundir as viagens em automóvel pelas estradas paulistas recém-construídas, ao mesmo tempo que o turismo – ainda incipiente – era apontado como prática social e estratégia de comunicação. Contribuições teóricas/metodológicas: O estudo aborda o conceito de viagens imaginativas aliado a uma metodologia de análise de fotografia na imprensa da década de 1920. Traz à discussão as mobilidades como categoria de análise complexa, em associação com estudos de comunicação.
A systemic model of furniture meant for stimulating development of a child
based on educational aids from M. Montessori
Authors: Dobrowolska Ewa , Błaszczak Iwona , Mielnik Agnieszka , Lisiecka Ewa
Published: August 2021

In furniture design, understood as a kind of evolutionary process, there is room for designer’s
creativity, but not in the sense traditionally accepted in the psychology of creation. The creativity of the designer
shapes the products of the evolutionary algorithm but does not replace them. This can be illustrated by the
genesis of any design, such as furniture that stimulates the development of the child. The Montessori pedagogy
leaves a lot of room for new designs of Montessorian teaching aids. The Montessori didactic material forms a
logically structured whole. It enables the child to move out of experience and sensual cognition; it serves not
only the development of the intellect but also the education of the whole personality. The Montessorian materials
take into account the child’s stage of development, corresponding to a given sensitive phase and the very logic of
things, so that the child, while learning, can embrace larger cognitive sequences, arouse a sense of aesthetics,
motivation, curiosity and interest, thus triggering various forms of activity.
Editorial Letter
Authors: Pascual y Cabo Diego , Foulis Elena , Prada Josh , Vergara Wilson Damian
Published: August 2021

Editorial Letter
Procedural Dungeon Generation: A Survey
Authors: Viana Breno M. F. , Dos Santos Selan R.
Published: August 2021

Procedural content generation (PCG) is a method of content creation entirely or partially done by computers. PCG is popularly employed in game development to produce game content, such as maps and levels. Representative examples of games using PCG are Rogue (1998), which introduced the rogue­like genre, and No Man’s Sky (2016), which generated whole worlds with fauna and flora. PCG may generate final contents, ready to be added to a game, or intermediate contents, which might be polished by human designers or work as an input level sketch to be interpreted by a level translator. In this paper, we survey the current state of procedural dungeon generation (PDG) research, a PCG subarea, applied in the context of games. For each work we selected in this survey, we examined and compared how they created game features, what type of level structure and representation they propose, which content generation strategy they applied, and, finally, we classify them according to the taxonomy of procedural content generation proposed by Togelius et al. (2016). The most relevant findings of our survey are: (1) PDG for 3D levels has been little explored; (2) few works supported levels with barriers, a game mechanic which temporarily blocks the player progression, and; (3) mixed-initiative approaches, i.e., software that helps human designers by making suggestions to the levels being created, are little explored.
Evaluation of the Effect of Intranasal Lidocaine in the Treatment of Spasticity in Patients with Traumatic Brain Injury
Authors: Dehnadi Moghadam Anoush , Hasanzadeh Hamed , Dehnadi Moghadam Fatemeh
Published: August 2021

Background: Spasticity following traumatic brain injury (TBI) is one of the most significant barriers of returning patients to their normal life. Spasticity caused by TBI does not have a specific or definitive treatment, and the clinical effect of pharmacologic treatments has not been significant. Methods: In this single-arm study, we evaluated 15 patients. For each patient with spasticity, treatment with oral baclofen 25 mg was started three times a day as a part of standard therapy. After 48 hours, if the spasticity did not decrease by at least one score in the Modified Tardieu or Ashworth scales, lidocaine 0.5% was administered as a continuous intranasal infusion. The initial dose of lidocaine was 1 mg/min, which was gradually increased to 2 mg/min. Spasticity and the frequency of spasms were assessed by Ashworth and modified tardieu scales (MTS) and Spasm Frequency Score (SFS), respectively. Heart rate (HR), respiratory rate (RR), mean arterial blood pressure (MAP), Richmond Agitation-Sedation Scale (RASS), Glasgow Coma Scale (GCS), and arterial oxygen saturation (SPo2) of patients were recorded during nine days of treatment. All data were analyzed by SPSS version 21. P-value less than 0.05 was considered as statistically significant. Results: Out of 15 participants in this study, 13 (86.7%) were male, and 2 (13.3%) were female (mean age: 29.26 ± 12.5 years). There were no significant differences in Ashworth Scale, Modified Tradieu Scale, RASS Score, GCS Score, MAP, SPo2 percentage, HR, RR, and the number of spasms per day between the time of initiation of treatment and the second day of baclofen treatment (P > 0.05). Evaluation of spasticity using Ashworth scale on the first and last days of lidocaine treatment showed a significant decrease in the mean spasticity (3.46 ± 0.51 and 1.46 ± 0.91, respectively; P < 0.001). Spasticity assessment using the MTS showed a significant reduction in the mean of the last day of treatment compared to the mean of the first day of treatment (3.6 ± 0.5 and 1.26 ± 0.51, respectively; P < 0.001). This decrease was also seen in the mean of the last day of treatment compared to the first day in SFS (13.3 ± 3.88 and 3.8 ± 0.51, respectively; P < 0.001). Comparison of HR, RR, MAP, RASS, GCS, and SPo2 on the first and last days of treatment did not show any statistical differences. Conclusions: Although continuous intranasal treatment with lidocaine can be effective in spasm reduction of patients with TBI, further studies with larger sample sizes and longer follow-up periods are required.
Psychological Adaptation to Transplanted Organ: A Hermeneutic Phenomenological Study
Authors: Sheikhalipour Zahra , Zaman Zadeh Vahid , Borimnejad Leili , Large Stephen R , Vahedi Leila
Published: August 2021

Background: While organ transplantation is a common surgical procedure worldwide, it is yet well-examined how the recipients of newly-transplanted organs adapt and accept a new organ from another body. Adaptation and acceptance of a vital organ from another person is a complex phenomenon, and medical staff needs to delve into this issue to provide appropriate care. Objectives: The present study aimed to explore the transplant recipients' experiences of adaptation to the transplanted organ. Method: A qualitative research design with a hermeneutic phenomenological approach was adopted in this study. In-depth unstructured interviews were conducted by one of the authors (Z. S.) in different locations across Iran. The purposive sampling method was used to select 20 transplant recipients (n = 4 kidney transplantation; n = 10 heart transplantation; n = 4 liver transplantations; and n= 2 blood transfusion). Results: The constitutive pattern emerged from the data was ‘Psychological adaptation to transplanted organ’, with three themes (namely ‘Alien organ,’ ‘Ensure of being the patch of togetherness,’ and ‘Durability of new organ in body’) and several sub-themes. Conclusions: According to the organ recipients' experiences, it takes time for the recipients to accept another person's organ as their own. The transplant team members need to openly and proactively discuss the many psychological and spiritual issues to which the newly-transplanted organ recipients are exposed to facilitate the adaptation and acceptance of the new organs.
Demographic and Socio-cultural Determinants of Intended and Unintended Pregnancies Among Women Under Cancer Treatment in Sistan and Baluchestan Province, Iran
Authors: Asadisarvestani Khadijeh , Navaee Maryam
Published: August 2021

Background: One of the main concerns during cancer treatment is the occurrence of pregnancy due to its wide range of complications. Objectives: This study aimed to determine some influential factors on pregnancy during cancer treatment among women of reproductive ages that were under cancer treatment. Methods: This cross-sectional study investigated 133 women of reproductive age, who were under cancer treatment, as well as women who had undergone chemotherapy or radiotherapy up to one year ago in Sistan and Baluchestan Province. Data were collected from three medical centers in Zahedan from 2019 to 2020, using a researcher-made questionnaire. Results: Regarding the pregnancy rate, 23.0% of women had pregnancy during cancer treatment, including unintended (52.0%) and intended (48.0%) pregnancies that 55.0% of these pregnancies led to abortion, and 45.0% to livebirths. The results highlighted that during treatment women with and without pregnancy differed significantly in age (P = 0.001), ethnicity (P = 0.024), husband’s education level (P = 0.014), woman’s occupation (P = 0.021), couple’s agreement on number of children (P = 0.024), and physician consultation about contraceptives (P = 0.048). The main predictors of pregnancy were the woman’s age pregnancy (OR = 0.927, P = 0.011), occupation (OR = 0.358, P = 0.046), and ethnicity (OR = 2.49, P = 0.045). Conclusions: Considering the complications of pregnancy during cancer treatment, health planners should pay more attention to family planning for women under treatment, particularly in less developed regions.
The Question of Regionalism
Authors: Senatore Mauro ,   Philosophy Documentation Center
Published: August 2021

In Of Grammatology (1967), Jacques Derrida explains that Western culture undergoes a transformation of knowledge and discourses that unfolds as the grammatization of experience. By resorting to the code of writing (grammē), as the elementary code of experience, modern sciences call into question ontological regionalism, that is, their traditional subordination to a fundamental ontology that assigns them the region of being corresponding to their field of investigation. Within this framework, Derrida develops a twofold schematic reading of Heidegger’s question of being in light of the question posed by scientific research to ontological regionalism. In this article, I focus on this reading, which has been overlooked by scholarship and yet undergirds Derrida’s later engagements with Heidegger, and I show that it draws on the overall interpretation of Heidegger’s thought developed by Derrida in his 1964–65 lecture course.
Ilgtspējīga vēsturisko ēku attīstība
Authors:   , Biseniece Edīte
Published: August 2021

Ēkas ir ne tikai liels enerģijas un resursu patērētājs, tās būtiski ietekmē arī cilvēku veselību, darbaspējas un nosaka vides dzīves kvalitāti. Ņemot vērā sektora lielumu, esošajam ēku fondam ir milzīgs enerģijas ietaupījuma potenciāls, kas var palīdzēt sasniegt Eiropas Savienības zaļā kursa mērķus un panākt tautsaimniecības transformāciju uz modernu, resursu ziņā efektīvu un konkurētspējīgu ekonomiku. Lielākie izaicinājumi ēku atjaunošanas jomā skar vēsturiskās ēkas, kuru fasādes nedrīkst mainīt, lai saglabātu to kultūrvēsturisko un arhitektonisko vērtību. Politikas veidotāji un ēku īpašnieki ir dilemmas priekšā – saglabāt ēku vēsturisko vērtību vai uzlabot to energoefektivitāti. Vēsturiskajām ēkām, lai saglabātu to kultūrvēsturisko vērtību, nav iespējama sienu siltināšana no ārpuses, tāpēc atliek sienu siltināšana no iekšpuses, kas ir tehniski riskants risinājums, it īpaši ēkām aukstā klimatā. Sienu siltināšana no iekšpuses ļoti būtiski maina sienas higrotermisko uzvedību, līdz ar to var izraisīt mitruma kondensāciju, pastiprinātu sāļu izdalīšanos, sala izraisītus bojājumus, pelējumu un citus bojājumus. Tāpēc pirms vēsturisko ēku atjaunošanas rūpīgi jāizvērtē riski, kas saistīti ar iespējamo mitruma akumulāciju konstrukcijās un sienas temperatūras samazināšanos. Nepieciešams izstrādāt jaunas metodes, ar kuru palīdzību šāda tipa ēkās varētu veikt drošu un ilgtspējīgu ēku atjaunošanu. Promocijas darba mērķis ir piedāvāt drošus un efektīvus risinājumus vēsturisko ķieģeļu un akmens sienu siltināšanai no iekšpuses. Mērķa sasniegšanai definēti vairāki uzdevumi: veikt vēsturiskajās ēkās izmantoto būvmateriālu testēšanu laboratorijā ar mērķi noteikt mitruma pārneses procesu konstrukcijā un ar to saistīto risku ietekmējušos faktorus; veikt dinamisko datormodelēšanu, lai aprakstītu vēsturisko mūra sienu dinamiskos higrotermiskos procesus ilgtermiņā, kā arī validēt šos modeļus, veicot higrotermisko procesu analīzi reālās ēkās ar ilgtermiņa mērījumu palīdzību; veikt dinamisko datormodelēšanu ar mērķi noteikt enerģijas patēriņa samazinājumu un mikroklimatu telpās pēc sienu siltināšanas no iekšpuses.
Effect of ion dose ratio on multilevel energy smoothing model of gas cluster
Authors: Luo Jin-Bao , Vasiliy Pelenovich , Zeng Xiao-Mei , Hao Zhong-Hua , Zhang Xiang-Yu , Zuo Wen-Bin , Fu De-Jun ,   School of Physical Science and Technology, Wuhan University, Wuhan 430072, China,   School of Power and Mechanical Engineering, Wuhan University, Wuhan 430072, China
Published: August 2021

In this study, two kinds of gas cluster ion beam energy modes with different ion dose ratios are proposed to improve the traumatic surface of n-Si (100) single crystal. In mode1, low-dose high-energy clusters and high-dose low-energy clusters are used, while in mode2, high-dose high-energy clusters and low-dose low-energy clusters are used. The results show that the flattening effect of mode 1 is better than that of mode 2, and the root mean square roughness of mode 1 and mode 2 are 0.62 nm and 1.02 nm, respectively. This is because in multi-level energy mode 2, high-dose high-energy clusters are used to bombard the target surface in the early stage, so that more ion damages will be left after high-energy cluster bombardment. In the later stage, low-dose low-energy clusters can only remove part of the ion damages, and the repair strength is not strong enough. In multi-level energy mode1, we first use low-dose high-energy clusters to bombard the surface of the target, so that the high-energy clusters can quickly remove the shape objects with high protrusion on the sample surface, and in the low-dose mode, it will not leave too many ion damages, which is conducive to the later repair. In the first stage of multi-level energy mode, high-dose low-energy clusters are used to bombard the target surface, which can not only reduce the ion loss, but also increase the time for low-energy clusters to repair ion damages, thereby yielding the optimal flattening effect. In order to verify the relationship among the damage removal, ion damage degree and cluster energy, a single energy cluster bombardment experiment with mechanical damage is carried out before the multi-level energy mode modification is studied. The results show that when the cluster ions are accelerated at 15 kV high voltage, the scratch removal efficiency is highest, and the surface scratch is very shallow, but the decease of roughness is not obvious; when the cluster ions are accelerated at 8 kV and 5 kV, the sample surface becomes fine and the remaining ion damages are least. At the same time, a comparison of the target bombarded by the multi-level energy mode 1 clusters with that by the single energy clusters shows that the multi-level energy mode can obtain a smoother target surface than the single 15 keV high-energy cluster treatment; the multi-level energy mode can better remove scratches and other wounds than the single 5 keV low-energy cluster treatment. Multistage energy mode 1 integrates the advantages of high and low energy clusters, thereby achieving the best flattening effect.
Reduction of CO2 by TiO2 nanoparticles through friction in water
Authors: Li Peng-Cheng , Tang Chong-Yang , Cheng Liang , Hu Yong-Ming , Xiao Xiang-Heng , Chen Wan-Ping ,   School of Physics and Technology, Wuhan University, Wuhan 430072, China,   School of Physics and Electronic Science, Hubei University, Wuhan 430062, China
Published: August 2021

The friction between some nanomaterials and teflon magnetic stirring rods has recently been found responsible for dye degradation by magnetic stirring in dark. In this work, a study is conducted on the reduction of CO2 by TiO2 nanoparticles under magnetic stirring in water. In a 100-mL reactor filled with 50-mL water, 1.00-g TiO2 nanoparticles and 1-atm CO2, 50-h magnetic stirring results in the formation of 6.65 × 10–6 (volume fraction) CO, 2.39 × 10–6 CH4 and 0.69 × 10–6 H2; while in a reactor without TiO2 nanoparticles, the same magnetic stirring leads only 2.22 × 10–6 CO and 0.98 × 10–6 CH4 to form. Four magnetic stirring rods are used simultaneously to further enhance the stirring, and 50-h magnetic stirring can form 19.94 × 10–6 CO, 2.33 × 10–6 CH4, and 2.06 × 10–6 H2. A mechanism for the catalytic role of TiO2 nanoparticles in the reduction of CO2 and H2O is established, which is based on the excitation of electron-hole pairs in TiO2 by mechanical energy absorbed through friction. This finding clearly demonstrates that nanostructured semiconductors are able to utilize mechanical energy obtained through friction to reduce CO2, thus providing a new direction for developing and utilizing the mechanical energy harvested from ambient environment.
Grain boundary character distributions in Si3N4 ceramics
Authors: Zhao Ming-Liang , Chen Song , Sun Feng , Zhang Jing , Lin Yan , Zhang Wei-Ru , Wang Wei-Guo ,   School of Materials Science and Engineering, Fujian University of Technology, Fuzhou 350118, China,   Sinoma Advanced Nitride Ceramics Co., Ltd, Sinoma Group, Zibo 255022, China,   Sinoma Hi Tech Materials Co., Ltd, Sinoma Group, Beijing 100021, China
Published: August 2021

The structure of grain boundary has an essential influence on the physical and mechanical properties, especially the high-temperature mechanical properties of silicon nitride ceramics. In the present work, the five-parameter analysis method which is established based on electron backscatter diffraction (EBSD), and stereology and statistics are used to study the grain boundary character distributions in the two commercial silicon nitride ceramic ball samples. These two samples are both fabricated by hot isostatic pressing but made in China and abroad, respectively. The results indicate that the misorientation distributions of the two samples radically deviate from the random distribution at a rotation angle of 180°, showing that the frequency of the relevant grain boundaries is dramatically higher than that of the randomly distributed ones. These grain boundaries are mainly those possessing the misorientations of [0 1 –1 0]/180° and [–1 2 –1 0]/180°, corresponding to Σ2 and Σ3 boundaries, respectively. The grain boundary inter-connections (GBICs) of the Σ2 boundaries are basically the same in the two samples, and they are dominated mainly by the {0 0 0 1}/{0 0 0 1} basal-to-basal inter-connection. However, the GBICs of Σ3 boundaries are quite different in the two samples. they primarily the {–1 2 –1 0}/{–1 2 –1 0} prismatic-to-prismatic inter-connection for the Σ3 boundaries in the sample made in China, but it is mainly the {1 0 –1 0}/{1 0 –1 0} prismatic-to-prismatic inter-connection for the Σ3 boundary in the sample made abroad. Crystallographic analysis shows that the planar coincidence site density (PCSD) for the {–1 2 –1 0}/{–1 2 –1 0}, {0 0 0 1}/{0 0 0 1} and {1 0 –1 0}/{1 0 –1 0} GBIC are 2.45 /nm2, 7.95 /nm2 and 9.10 /nm2, respectively, implying that the degree of the structural ordering increases in turn. Further discussion emphasizes that the grain boundaries possessing {1 0 –1 0}/{1 0 –1 0} GBIC and {0 0 0 1}/{0 0 0 1} GBIC should be one type of special boundaries due to their high degrees of structural ordering.
First-principles study of vacancy ordered structures, mechanical properties and electronic properties of ternary Hf-C-N system
Authors: Peng Jun-Hui , Tikhonov Evgenii ,   International Center for Materials Discovery, School of Materials Science and Engineering, Northwestern Polytechnical University, Xi’an 710072, China,   Department of Materials Engineering, Taiyuan Institute of Technology, Taiyuan 030008, China
Published: August 2021

The thermal-mechanical properties of transition metal carbonitrides can be affected by the concentration and ordering of vacancies besides the C/N atomic ratio. However, there are few reports on the vacancy ordered structure of ternary transition metal carbonitrides. In the present paper, the first-principles method is used to study the vacancy ordered structures, mechanical properties, electronic properties and the effect of vacancies on the ternary Hf-C-N system. Firstly, the crystal structures of Hf-C-N system is examined by the first-principles and evolutionary algorithms implemented in USPEX under ambient pressure, and eight thermodynamical stable vacancy ordered structures are found, each of which has a rock-salt structure, and is also dynamical and mechanical stable, which are verified by the calculations of their phonon dispersion curves and elastic constants. The vacancies are occupied at the [Hf6] octahedral interstices, which replace the positions of non-metal atoms. Their crystallographic data such as space group, lattice constants are also predicted. To the best of our knowledge, there is no report on the Hf-C-N vacancy ordered structures and these structures investigated here in this work are all found for the first time. Then their mechanical properties are calculated. The Hf-C-N vacancy ordered structures all have very high bulk, shear and elastic modulus and hardness. It is found that except for C∶N = 1∶4, for the Hf-C-N system with the same C/N ratio the moduli, Vickers hardness values, and Pugh’s ratios decrease with the increase of the concentration of vacancy. However, the Vickers hardness of Hf6CN4 (the concentration of vacancy is equal to 1/6) is higher than that of Hf5CN4 (no vacancy), that is so-called vacancy hardening. Finally, the electronic density of states and the crystal orbital Hamilton populations are calculated. The chemical bonding of Hf-C-N vacancy ordered structure is analyzed, which is a mixture of covalence and metallic and is similar to that of binary transition metal carbides and nitrides. With the increase of the concentration of vacancy, the total bond strength decreases, and then the modulus decreases for Hf-C-N compound.
Simulation study of underwater intruder localization based on transfer learning
Authors: Lei Bo , He Zhao-Yang , Zhang Rui ,   School of Marine Science and Technology, Northwestern Polytechnical University, Xi’an 710072, China,   Qingdao Research Institute, Northwestern Polytechnical University, Qingdao 266200, China
Published: August 2021

Forward scattering of the target could cause the amplitude and phase aberration of the received sound field, which received attentions in harbor monitoring and anti-submarine. However, the localization under forward scattering configuration is a challenging task due to the strong direct blast. The method based on sensitive kernel function which exploit the aberration of the received signals is sensitive to the environment mismatch and a localization method based on transfer learning framework is developed. The envelopes of aberrations caused by the forward scattering of intruder are firstly extracted by applying pulse compression technique on the received signals, and then normalized by comparing with the case of intruder absent. The data set near the first arrivals on the normalized aberrations are selected as the learning physical parameters. A convolution neural network is trained with these data generated by the forward scattering model to establish a mapping relationship between intruder’s localization and the aberrations of received signal, thus the localization problem is transformed into classification. In the second step, the parameters of the convolutional pooling layer in the pre-trained model are frozen in the transfer learning procedure, and the parameters of the fully connected layer in the pre-trained model are updated using a small amount of data under the fluctuated environment. Simulation of the localization of ellipsoidal targets with a signal-to-noise ratio of 0 dB under a shallow water environment is performed for a scenario to explore the robustness of the method. The results show that the accurate target localization could be achieved in the case of sound velocity profile mismatch. Also, the method is not significantly sensitive to the target scattering function, sound properties of sediment and deployment of transceivers. The sensitivities to the waveguide amplitude and phase fluctuations are further modeled. The results show that good localization accuracy can be obtained in a relatively stable environment, and results are distinguished between the presence and absence of the target. Since the proposed method is derived by the model and real data, the accurate scattering model and sufficient training data are not significantly necessary. The method may provide a promising way for forward scattering detection.
Performance analysis of thermoelectric system based on radiative cooling and greenhouse effects
Authors: Chen Hao , Wang Cun-Hai , Cheng Zi-Ming , Wei Lin-Yang , Wang Fu-Qiang , Zhang Xin-Xin ,   School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing 100083, China,   School of New Energy, Harbin Institute of Technology (Weihai), Weihai 264209, China,   School of Metallurgy, Northeastern University, Shenyang 110819, China
Published: August 2021

Electricity power has served as an essential source in our daily life. However, some remote areas that are difficult to be covered by the power grid, are still facing a serious shortage of electricity for outdoor equipment such as field monitors. Off-grid power is the alternative power in such areas, but there arise apparently economic and environmental problems. Therefore, the development of portable, pollution-free and sustainable power supply equipment has vital research significance. In this paper, based on the radiative cooling and greenhouse effects, a passive thermoelectric system without any active energy input is proposed. A square copper plate coated with a thin film of acrylic acid doped with SiO2 particles, with an average emissivity value of 0.937, is selected as a radiative cooling material. The commercial polyolefin film with a thickness of 0.12 mm is selected as a greenhouse material. The radiative cooling effect cools the cold end of the thermoelectric generator (TEG) during the nighttime, the greenhouse effect during the daytime is utilized to increase the temperature of the hot end of the TEG. The radiative cooling effect and the greenhouse effect both result in the increase of the temperature difference between the cold and hot ends, and thus obtaining the output power. During the period of time from June 17 to June 21, 2020, the performance of the designed system at the location of Shaanxi, China was evaluated experimentally, and the weather condition effects were also studied. The experimental results show that a stable temperature drop of ～1.1 ℃ of the cold end is achieved via the radiative cooling effect at night. Owing to the greenhouse effect, the temperature increase of the hot end reaches a maximum value of 13.9 ℃. When the average ambient humidity decreases from 45% to 20%, the average temperature difference between the hot end and cold end of the thermoelectric module increased from 1.6 to 1.9 ℃ throughout the day, and the average power increased from 47.8 to 67.3 mW/m2, indicating that the equipment can have better power generation performance under the condition of 20% ambient humidity. The device developed in this work realizes all-day passive output and shows that it has potential applications in off-grid power supplies.
Application and analysis of three-layer-core structure in single-mode large-mode-area fiber with low bending loss
Authors: Zheng Si-Wen , Liu Ya-Zhuo , Luo Xiao-Ling , Wang Li-Hui , Zhang Na , Zhang Jing-Jing , Jin Chuan-Yang , Xu Bing-Li , Qu Qiang , Chen Ling ,   Army Academy of Armored Forces, Beijing 100072, China
Published: August 2021

A three-layer-core single-mode large-mode-area fiber with low bending loss is investigated in this paper. The three-layer structure in the core which is comprised of core-index layer, cladding-index layer and depression-index layer, can achieve large-effective-area Aeff while maintaining low-bending-loss without deteriorating cutoff behaviors. The large-mode-area of 100–330 μm2 can be achieved in the fiber. The effective area Aeff can be further enlarged by adjusting the layer parameters. Furthermore, the bending property can be improved in this three-layer-core structure. The bending loss can decrease by 2–4 orders of magnitude compared with the bending loss of the conventional step-index fiber with the same Aeff. These characteristics of three-layer-core fiber suggest that it can be used in large-mode-area wide-bandwidth high-capacity transmission, or high-power optical fiber laser and amplifier in the optical communications, which can be conducive to studying the basic physical layer structure of big data storage, reading, calculation and transmission applications and so on.
Multi-parameter tunable phase transition based terahertz graphene plasmons and its application
Authors: Li Ze-Yu , Jiang Qu-Han , Ma Teng-Zhou , Yuan Ying-Hao , Chen Lin ,   School of Optical-Electrical and Computer Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China,   Shanghai Key Labortary of Modern Optical System, University of Shanghai for Science and Technology, Shanghai 200093, China,   Shanghai Customs Industrial Products and Raw Materials Testing Technology Center, Shanghai 200135, China
Published: August 2021

The active modulation of the amplitude and phase of terahertz wave has been widely adopted in terahertz functional devices. The current metal-insulator-metal metasurface structure combined with two-dimensional materials such as graphene can realize dynamic control of terahertz amplitude/phase, but it has some disadvantages such as less freedom of control (voltage or light intensity), complex processing technology and high price of metasurface structure. In this article, we propose a prism-coupled matel-insulator-graphene (MIG) phase regulation structure. This structure can not only control the phase by adjusting the Fermi level in the usual way, but also change the intrinsic loss and radiation loss of the structure by adjusting the thickness of the air gap and the number of layers of pre-spread graphene, so that the phase of the structure can be controlled, which is determined by the difference between intrinsic loss and radiation loss of the fabric, which is closely related to this structure staying in the under-coupling/over-coupling state. The adjustment of the structural phase can also lead the magnitude of the terahertz Goos–Hänchen(GH) displacement and its positive sign and negative sign to be selected. Furthermore, it is shown that the under-coupling state and the over-coupling state of the structure have an important effect on the coincidence of the Goos–Hanchen (GH) displacement. The results show that by dynamically adjusting the thickness of the air gap and the Fermi level of graphene, and changing the eigenloss and radiation loss of the system, the phase regulation can be achieved. Finally, the transition from overdamped to underdamped state is realized. In this physical process, the GH displacement of the system will also change obviously. This paper puts forward the structure of the process with simple processing technology (no need to microstructure), tunable high degrees of freedom (available graphene Fermi level and air gap dynamic regulation, also could be regulated and controlled by controlling the graphene layers) in comparison with the phase modulator of metal-insulator-metal super surface structure. The results of this paper open up a new way of developing the multi-parameter tunable terahertz sensor components.