bluuebunny/crossref_metadata_2025 huggingface dataset:
KAJIAN LAJU EKSPLOITASI HASIL TANGKAPAN DI SEKITAR KAWASAN TAMAN WISATA PERAIRAN (TWP) PULAU PIEH
Authors: Monika Defra , Arlius Arlius , Masrizal Masrizal
Published: February 2022

The study is done at October to December 2018 in Tourist Waters Park Area Pieh Island.Choice of location for the Marine Park Area Pieh Island and the sea all around, located in two cities is Padang City and Pariaman city and one district Padang Pariaman doing by deliberately (purposive sampling). Research aims to known the exploitation of fish and aimed to know the state of resources fish in Marine Park Area Pieh Island.The research results show that the rate of the exploits of fish in Marine Park Area Pieh Island the longest wait with an average value of the the exploits of 0,75731 , the rate of the exploits of has the highest poverty rate is found in species of Stolephorus sp , Euthynnus sp, Rastrelliger spp, Sardinella spp, Selaroides sp, Leiognathus spp, Scomberoides sp, Caranx sp, Alectis sp, Sphyraena sp, Acanthocybium sp, Lutjanus  sp, Trihiurusavala sp, Katsuwonus sp, Epinephelus spp, Arius spp, Lolligo spp with the size of the taxes exploits of >0,5. The lowest exploitation is found in species of fish, Decapterus sp, Therapon spp , Thunnus sp still under the < 0,5, still can be used optimally. Instrument get used to have a low selektifitas where all of the size of fish arrested so that reduces the chance to the fish grow can indeed be resulted in excess catch (overfishing).Keyword : exploitation, Utilization, Marine Park Area Pieh IslandABSTRAK Kajian eksploitasi hasil tangkapan di sekitar Kawasan Taman Wisata Perairan Pulau Pieh berperan untuk mengetahui tingkatan eksploitasi. Tujuan penelitian ini adalahUntuk mengetahui Hasil Tangkapan ikan dan mengetahui hasil eksploitasi ikan. Penentuan lokasi penelitian dilakukan dengan sengaja (purposive sampling) yakni pada TPI Pasie Nan Tigo Kota Padang, TPI Karan Aur Kota Pariaman, TPI Pasar Ulakan Kabupaten Padang Pariaman dan PPI Pasir Baru Kabupaten Padang Pariaman.Hasil penelitian menunjukkan Tingkat eksploitasi ikan di TWP Pulau Pieh dengan rata – rata nilai eksploitasi 0,75731, laju eksploitasi tertinggi terdapat pada jenis ikan Teri, Tongkol Kembung, Sarden, Selar, Peperek, Talang – Talang, Kuwe, Barakuda, Tenggiri, Kakap, Layur, Cakalang, Kerapu, Gole – Gole, Manyung dan Cumi – Cumi dengan besaran eksploitasi > 0,5. Laju Eksploitasi Terendah terdapat pada jenis ikan Layang, Tuna dan Kerong – kerong yang masih dibawah angka ketetapan < 0,5, sehingga masih dapat dimanfaatkan secara optimal. Kondisi sumberdaya ikan di TWP Pulau Pieh sudah mengalami overfishing atau kelebihan tangkap dikarenakan tingginya laju eksploitasi penangkapan. Alat tangkap yang digunakan memiliki tingkat selektifitas yang rendah sehingga dapat mengakibatkan kelebihan tangkap. Kata Kunci: Eksploitasi, Pemanfaatan, TWP Pulau Pieh
Respon mahasiswa terhadap perkuliahan online
Authors: Rahman Taufik , Basri Moh. Hasan , Mashuri Hendra , Prasetyo Dyas Andry
Published: February 2022

Penelitian ini bertujuan untuk mengetahui respon mahasiswa calon guru PJOK terhadap perkuliahan daring. Metode penelitian menggunakan pendekatan kuantitatif dengan jenis penelitian survei. Instrumen penelitian menggunakan kuisioner respon mahasiswa terhadap perkuliahan dalam jaringan (daring). Sampel penelitian sebanyak 124 mahasiswa. Teknik analisis yang digunakan adalah desriptif kuantitatif. Hasil penelitian menunjukkan bahwa respon mahasiswa terhadap perkuliahan daring ternyata kurang efektif. Mayoritas mahasiswa mengalami kendala yang berarti selama perkuliahan dilaksanakan sehingga membuat mahasiswa kesulitan untuk menyerap dan memahami materi perkuliahan. Mahasiswa menginginkan metode belajar yang lebih kreatif atau perkuliahan dilaksanakan secara luring jika kondisi memungkinkan. Perkuliahan bisa dilaksanakan dengan pendekatan kombinasi (daring-luring) dan pendekatan kreatif untuk Prodi Penjaskesrek yang bisa mendorong mahasiswa dan dosen untuk bisa memanfaatkan lingkungan sebagai bahan belajar yang mendukung perkuliahan daring.
Tanggapan mahasiswa pendidikan jasmani terhadap pembelajaran online
Authors: Nopiyanto Yahya Eko , Ibrahim Ibrahim
Published: February 2022

Tujuan penelitian ini adalah untuk mengetahui tanggapan mahasiswa penjas terhadap pembelajaran daring pada semester genap 2020/2021. Metode yang digunakan adalah penelitian kuantitatif dengan pendekatan survei. Teknik sampling yang digunakan yaitu purposive sampling, denganjumlah sampel 101 mahasiswa penjas. Teknik pengumpulan data menggunakan angket yang disebarkan melalui google form. Teknik analisis data menggunakan deskriptif kuantitatif persentase. Berdasarkan hasil analisis data diketahui bahwa: 55,6% mahasiswa yang menyatakan bahwa pembelajaran daring mampu mengarahkan untuk belajar mandiri; 29,3% mahasiswa menggunakan laptop milik sendiri sebagai perangkat pembelajaran; 58,6% mahasiswa menggunakan koneksi internet dari bantuan pemerintah; 92,9% mahasiswa mengalami hambatan jaringan internet; 61,4% mahasiswa memiliki jarak tempuh kurang dari 1 jam untuk mendapatkan akses internet; 69,7% mahasiswa menggunakan Whatsapp group sebagai media pembelajaran; 75,2% mahasiswa menggunakan Whatsapp group sebagai media pengumpulan tugas; 45,5% mahasiswa memilih tugas secara berkelompok selama pembelajaran daring; 61,4% mahasiswa menggunakan sumber belajar dari dosen; 56,4% mahasiswa memilih bentuk tugas latihan soal. Mahasiswa penjas memberikan tanggapan yang positif terhadap pembelajaran daring dengan persentase sebesar 55,6%. Sehingga dapat disimpulkan bahwa pembelajaran daring pada masa pandemi Covid-19 efektif diterapkan kepada mahasiswa penjas.
Profile of physical fitness college student during covid-19 pandemic
Authors: Saleh Muhammad , Septiadi Firman
Published: February 2022

This study aims to determine the level of physical fitness (VO2Max) of prospective new students during the Covid-19 pandemic. This type of research is descriptive with a quantitative approach. The method used is a survey with data collection techniques using tests and measurements. The sample in this study was the prospective new students 20 male and 8 female, the total sample 28 people. This study uses a total sampling technique. The data analysis technique uses a frequency distribution. Data collection was carried out in the yard of Building D, Muhammadiyah University of Sukabumi. The test instrument used in this study is the Multistage Fitness Test (MFT) or bleep test. The results showed that the majority of prospective new students were in the very poor category with 18 men (90%) and less than 2 (10%), while women who were in the very poor category 7 people (87.5) and category of less than 1 person (12,5%). It can be concluded that the level of physical fitness of prospective new students is in the very poor category.
HASIL BELAJAR SISWA KELAS V PADA PELAJARAN MATEMATIKA DENGAN MENGGUNAKANALAT PERAGA KONKRET DI SDN 11 MERAPI BARAT
Authors: Nugraha Abi , Maharani Siti Dewi , Gandi Indra
Published: February 2022

AbstractThis study aims to improve the learning outcomes of fifth grade students in learning materials using concrete teaching aids. The method of this research is Classroom Action Research, which consists of planning, implementing, observing, and reflecting. The results showed that there was an increase in student learning outcomes. This can be seen from the learning completeness of students, starting from the first cycle with a percentage of 66.66%, in the second cycle it increased by 75%, and in the third cycle it increased by 91.66%. Based on these results, it can be concluded that research using concrete teaching aids can improve the learning outcomes of fifth grade students of SD Negeri 11 Merapati Barat. Key Words: Concrete teaching aids, learning outcomes AbstrakPenelitian ini bertujuan untuk meningkatkan hasil belajar siswa kelas V pada pembelajaran matermatika dengan menggunakan media alat peraga konkret. Metode penelitian ini adalah Penelitian Tindakan Kelas, yang terdiri dari tahap perencanaan, pelaksanaan, observasi, dan refleksi. Hasil penelitian menunjukkan bahwa terdapat peningkatan pada hasil belajar peserta didik. Hal ini dapat dilihat dari ketuntasan belajar peserta didik, mulai dari siklus I dengan persentase sebesar 66,66%, pada siklus II meningkat sebesar 75%, dan pada siklus III meningkat sebesar 91,66%. Berdasarkan hasil penelitian tersebut dapat disimpulkan bahwa penelitian dengan menggunakan media alat peraga konkret dapat meningkatkan hasil belajar siswa kelas V SD Negeri 11 Merapati Barat. Kata Kunci: Alat peraga konkret, hasil belajar
HASIL BELAJAR PESERTA DIDIK TENTANG MACAM-MACAM GAYA DENGAN MENGGUNAKAN WHITEBOARD ANIMATION DI KELAS IV SD NEGERI 22 LAHAT
Authors: Karim Rinta Viranda , Toybah Toybah , Mashannuddin Mashannuddin
Published: February 2022

AbstractThis study aims to describe efforts to improve learning outcomes of the fourth grade students in type of forces materials using Whiteboard Animation Media at Elementary School number 22 Lahat. This research applied classroom action research method with three cycles of action. The research subjects were fourth grade students, with the total of 9 students consisting of 4 boys and 5 girls. The results of the study indicated that the value of student learning outcomes has increased. This can be seen in the percentage of student learning completeness in the first cycle of 55.5%, the second cycle increased to 77.7%, the third cycle increased to 88.8%. In addition, based on the results of observations, scores of students’ activities have increased. In the first cycle, the percentage of student activity in learning reaches 61.5% with a moderately active category. In the second cycle, it has increased to 70.3% with an active category. In the third cycle, it increased to 80.5% in the very active category. This indicated that the application of Whiteboard Animation Learning Media can improve the learning outcomes of fourth grade students about type of forces materials at SD Negeri 22 Lahat.             Keywords: Whiteboard Animation media, learning outcomes. AbstrakPenelitian ini bertujuan untuk mendeskripsikan upaya peningkatan hasil belajar peserta didik kelas IV tentang macam-macam gaya menggunakan Media Whiteboard Animation di SD Negeri  22 Lahat. Penelitian ini menggunakan metode penelitian tindakan kelas dengan tiga siklus tindakan. Subjek penelitian adalah peserta didik kelas IV, yang berjumlah 9 peserta didik terdiri dari 4 laki-laki dan 5 perempuan. Dari hasil penelitian menunjukkan bahwa nilai hasil belajar peserta didik mengalami peningkatan, hal ini terlihat pada persentase ketuntasan belajar peserta didik di siklus I sebesar 55,5%, siklus II mencapai 77,7 %, siklus III persentase ketuntasan belajar peserta didik meningkat mencapai 88,8%. Selain itu, aktivitas peserta didik yang mengalami peningkatan, pada siklus I presentase aktivitas peserta didik dalam belajar mencapai 61,5% dengan kategori cukup aktif, pada siklus II mengalami peningkatan menjadi 70,3% dengan kategori aktif, dan pada siklus III mengalami peningkatan menjadi 80,5% dengan kategori sangat aktif. Hal ini membuktikkan bahwa melalui Media Pembelajaran Whiteboard Animation dapat meningkatkan hasil belajar peserta didik kelas IV tentang macam-macam gaya di SD Negeri  22 Lahat. Kata kunci : Media Whiteboard Animation, hasil belajar.
ANALISIS PERANGKAT PENILAIAN BERBASIS SELF-ASSESSMENT PADA MATA KULIAH PRAKTIKUM BODY PENGECATAN PROGRAM STUDI PENDIDIKAN TEKNIK MESIN
Authors: Debora Debora , Sintha Indria
Published: February 2022

Praktikum adalah salah satu pembelajaran khususnya pada mata kuliah praktikum body pengecatan, yaitu bukan sekedar penguasaan konten materi yang diajarkan, namun mahasiswa harus mampu menggunakan pengetahuan dan keterampilan. Penelitian ini di lakukan untuk mengetahui analisis presentase respon dari responden dalam perlunya penerapan penilaian diri (Self-Assessment) pada mata kuliah praktikum body pengecatan. Penelitian ini merupakan penelitian deskriptif kuantitatif dengan menggunakan metode survei, teknik sample purposive sampling. Uji Validitas menggunakan analisis korelasi rumus Product Moment dari Pearson dengan hasil 29 butir instrumen yang valid. Sedangkan untuk mengetahui reliabilitasnya, data dianalisis menggunakan rumus koefisien alpha, kemudian hasilnya di bandingkan dengan tingkat keandalan koefisien korelasi. Berdasarkan analisis tersebut, instrument penelitian ini dinyatakan reliabel untuk digunakan dalam pengumpulan data. Hasil penelitian yang diperoleh menunjukkan bahwa skor rata-rata yang diperoleh oleh responden sebesar 95.254. Secara keseluruhan, nilai yang diperoleh siswa 82.12%. Hal tersebut dapat disimpulkan bahwa perlunya pelaksanaan self-assessment pada mata kuliah praktikum body pengecatan.
PENGEMBANGAN JOBSHEET ELEKTRONIK PRAKTIK PENGELASAN GMAW (GAS METAL ARC WELDING)
Authors: Sudiyono Sudiyono , Musyono Ari Dwi Nur Indriawan , Budiman Febrian Arif , Septiyanto Angga
Published: February 2022

Penelitian ini bertujuan untuk mengembangkan jobsheet elektronik pada materi Praktik pengelasan GMAW (Gas metal Arc Welding) yang layak dan praktis untuk digunakan dalam pembelajaran. Metode penelPenelitian ini bertujuan untuk mengembangkan jobsheet elektronik pada materi Praktik pengelasan GMAW (Gas metal Arc Welding) yang layak dan praktis untuk digunakan dalam pembelajaran. Metode penelitian yang digunakan yaitu metode penelitian dan pengembangan dengan desain penelitian four-D model. Subjek penelitian adalah mahasiswa, ahli materi, dan ahli media. Teknik analisis data yang digunakan dalam penelitian ini adalah deskriptif kuantitatif menggunakan analisis persentase. Hasil penelitian menunjukkan bahwa jobsheet elektronik hasil pengembangan sangat layak dan sangat praktis untuk digunakan dalam pembelajaran praktik pengelasan GMAW. Hal ini terlihat dari hasil validasi ahli materi dengan skor persentase sebesar 84,64 % atau pada kategori sangat layak, sedangkan skor validasi ahli media sebesar 85,73 % juga pada kategori sangat layak. Selain itu hasil penilaian kepraktisan oleh mahasiswa memperoleh skor sebesar 81,33 % atau sangat praktis digunakan.itian yang digunakan yaitu metode penelitian dan pengembangan dengan desain penelitian four-D model. Subjek penelitian adalah mahasiswa, ahli materi, dan ahli media. Teknik analisis data yang digunakan dalam penelitian ini adalah deskriptif kuantitatif menggunakan analisis persentase. Hasil penelitian menunjukkan bahwa jobsheet elektronik hasil pengembangan sangat layak dan sangat praktis untuk digunakan dalam pembelajaran praktik pengelasan GMAW. Hal ini terlihat dari hasil validasi ahli materi dengan skor persentase sebesar 84,64 % atau pada kategori sangat layak, sedangkan skor validasi ahli media sebesar 85,73 % juga pada kategori sangat layak. Selain itu hasil penilaian kepraktisan oleh mahasiswa memperoleh skor sebesar 81,33 % atau sangat praktis digunakan.
La naturaleza de la ciencia que se enseña desde la práctica reflexiva de los profesores de ciencias
Authors: Carreño Díaz Andrés Julian
Published: February 2022

El presente libro habla sobre la investigación sobre “La Naturaleza de la Ciencia (NdC) que se enseña desde la práctica reflexiva de los profesores de ciencia”, la cual analiza las principales características de la NdC que enseña un grupo de profesores de ciencias, quienes participan en un proceso de formación en servicio; la práctica reflexiva que ellos desarrollan desde la visión de consensos; el enfoque de parecido familiar (EPF); la enseñanza implícita y explícita de la NdC, y los niveles de reflexión. En general, esta investigación busca obtener una mejor comprensión de la ciencia que se enseña en los colegios de Bogotá, Colombia.
Kritik Metafisika: Studi Komparatif Pemikiran Heidegger (1889-1976 M) dan Suhrawardi (1154-1191 M)
Authors: Arif Muhammad
Published: February 2022

Heidegger dan Suhrawardi memiliki pendapat yang seirama dalam mengonsepsikan kritik metafisika. Menurut mereka Ada itu hanya dapat tersingkap melalui interaksi langsung, ontological-existential dalam bahasa Hidegger dan idlafah isyraqiyah dalam bahasa Suhrawardi. Persamaan gagasan dari dua tokoh yang berbeda zaman dan tradisi ini jelas sangat menarik untuk dikaji lebih lanjut, sehingga artikel ini mengulas tentang apa saja persamaan dan perbedaan dari dua filsuf tersebut. Artikel ini memiliki keunikan tersendiri dibanding penelitian-penelitian yang ada, karena masih belum ditemukan penelitian yang mengkomparasikan pemikiran kedua filsuf tersebut. Bahkan, pada umumnya penelitian yang ada lebih menempatkan pemikiran Suhrawardi sebagai kajian tasawuf falsafi dalam dimensi logika, epistemologi, metafisika, dan bukan kritik metafisika sebagaimana menjadi tema utama artikel ini. Terakhir, artikel ini menemukan bahwa Heidegger dan Suhrawardi memiliki beberapa perbedaan dan persamaan. Perbedaan antara keduanya tampak dalam pijakan berpikir, orientasi pemikiran, dan pandangan keduanya tentang keakuan performatif, sementara dalam gagasan kritik metafisika, keduanya berada di garis yang sama.
Existence of periodic traveling waves in Fermi-Pasta-Ulam type systems on 2D-lattice with saturable nonlinearities
Authors: Bak Sergiy , Kovtonyuk Galyna
Published: February 2022

The Fermi-Pasta-Ulam-type systems with saturable nonlinearities, namely, infinite systems of particles on a two dimensional lattice, have been considered. The main result concerns the existence of traveling-wave solutions with periodic relative displacement profiles. By means of critical point theory, sufficient conditions for the existence of such solutions have been obtained.
Topological properties of closed weakly m-semiconvex sets
Authors: Osipchuk Tetiana
Published: February 2022

The present work considers properties of generally convex sets in the $n$-dimensional real Euclidean space $\mathbb{R}^{n}$, $n>1$, known as weakly $m
$-semiconvex, $m=1,2,\ldots ,n-1$. For all that, the subclass of not $m$-semiconvex sets is distinguished from the class of weakly $m$-semiconvex
sets. A set of the space $\mathbb{R}^{n}$ is called \textbf{\emph{$m$-semiconvex}} if, for any point of the complement of the set to the whole
space, there is an $m$-dimensional half-plane passing through this point and
not intersecting the set. An open set of $\mathbb{R}^{n}$ is called weakly $m$-semiconvex if, for any point of the boundary of the set,
there exists an $m$-dimensional half-plane passing through this point and
not intersecting the given set. A closed set of $\mathbb{R}^{n}$ is called
\textbf{\emph{weakly $m$-semiconvex}} if it is approximated from the outside
by a family of open weakly $m$-semiconvex sets. An example of a closed set
with three connected components of the subclass of weakly $1$-semiconvex but
not $1$-semiconvex sets in the plane is constructed. It is proved that this
number of components is minimal for any closed set of the subclass. An
example of a closed set of the subclass with a smooth boundary and four
components is constructed. It is proved that this number of components is
minimal for any closed, bounded set of the subclass having a smooth boundary
and a not $1$-semiconvex interior. It is also proved that the interior of a
closed, weakly $1$-semiconvex set with a finite number of components in the
plane is weakly $1$-semiconvex. Weakly $m$-semiconvex but not $m$-semiconvex
domains and closed connected sets in $\mathbb{R}^{n}$ are constructed for
any $n\geq 3$ and any $m=1,2,\ldots ,n-2$.
Voices from the Margins
Authors: del Campo Mercedes
Published: February 2022

Voices from the Margins explores the particular emphasis that women writers of Troubles short fiction have placed on gender and the everyday, two areas which have often been relegated to the margins of the «official story» about the Northern Irish conflict and peace process. Women’s Troubles short stories integrate the domestic plot into the larger historical framework of political violence, reconceptualizing and blurring the boundaries between the private and the public and capturing the many ways in which the conflict has impacted and been disruptive of the private space. This book shows how these women have rewritten the «official story» with narratives that foreground the personal histories of the Troubles over a public History which has largely been based on the division between the pro-state and anti-state nationalisms in Northern Ireland.
La ligue d’Action française (1905-1936)
Authors: Schmidt-Trimborn Anne-Catherine
Published: February 2022

L’Action française, Charles Maurras, et le maurrassisme ont fait l’objet ces
dernières décennies d’un renouveau historiographique conséquent. Dans
le dispositif maurrassien, si les dirigeants et les publications, à commencer
par le quotidien L’Action française ont été largement étudiés, la ligue
d’Action française, née en 1905 et dissoute en 1936, a été beaucoup moins
analysée. C’est à cette organisation, à son implantation et au type de
militantisme qui la structure que s’attache cet ouvrage en posant des
questions qui ne sont simples qu’en apparence : qui sont les militants et les
militantes de l’Action française ? Où se situent les sections de la ligue
nationaliste ? Comment s’organisent ses activités et se marque son action
sur le terrain, non seulement en région parisienne mais aussi en province ?
C’est à ces différentes interrogations que s’emploie à répondre ce livre issu
d’une thèse soutenue à l’université de Lorraine-Metz en 2017. L’ouvrage
permet ainsi, à partir de sa sociologie, de ses pratiques militantes et des
jeux d’échelles entre le national et le local, de dessiner un portait renouvelé
d’une ligue nationaliste qui, après la Ligue des patriotes de Paul Déroulède
moribonde avant 1914 fut au coeur de l’histoire militante du nationalisme
français avant de se voir concurrencée par les Jeunesses patriotes de Pierre
Taittinger à partir de la seconde moitié des années 1920.
PENGARUH GAYA KEPEMIMPINAN TRANSFORMASIONAL TERHADAP KOMUNIKASI DAN DAMPAKNYA PADA KINERJA PEGAWAI BADAN PENDAPATAN DAERAH (BAPENDA) KABUPATEN MOJOKERTO
Authors: Subendi Antor , Hadiyati Ernani , Suswati Endang
Published: February 2022

The purpose of this study was to examine the effect of transformational leadership style and communication onemployee performance, examine the effect of transformational leadership style on communication, andcommunication strengthens the effect of transformational leadership style on employee performance. Thepopulation of this study were 45 employees of the Bapenda Mojokerto Regency so that all of them were taken assamples or used total sampling technique. Methods of data collection using survey techniques anddocumentation. The data analysis of this research used descriptive data analysis technique of percentage andPartial Least Square (PLS). The results showed that there was a significant positive effect of transformationalleadership style and communication partially on employee performance. There is a significant positive effect oftransformational leadership style on employee communication. Communication does not strengthen theinfluence of transformational leadership style on employee performance, meaning that communication cannotmediate the effect of transformational leadership on employee performance.
Paracossulus thrips (Hübner, 1818) (Cossidae) and Lignyoptera fumidaria (Hübner, 1825) (Geometridae) – two Lepidoptera genera new for Serbia with a review of the distribution of these two Habitats Directive species in the Balkan Peninsula
Authors: Beshkov Stoyan , Nahirnić-Beshkova Ana
Published: February 2022

Paracossulus thrips (Hübner, 1818) and Lignyoptera fumidaria (Hübner, 1825), both species listed on Annex II of the Council Directive 92/43/EEC, are reported for the first time for Serbia from two distinct localities on Vidlič Mt. Some new localities from the edge of the range of both these species are reported from Bulgaria. Previous reports of these species in the Balkan Peninsula are summarized and comments are given on the habitats, threats and conservation requirements of both species. Serbian vernacular names for both species are proposed.
Effect of Multi-Objective Optimization for Double Pulse Resistance Spot Welded Joints of Ferritic Stainless Steel
Authors:   Dept of Automobile Engineering, Velammal Engineering College, Chennai, India, Chandran V , Madhivanan K ,   Dept of Mechanical Engineering, SV College of Engineering, Tirupati, India, Arockia Jaswin M ,   Dept of Mechanical Engineering, Velammal Engineering College, Chennai, India, Subramanian A ,   Integral Coach Factory, Chennai, India
Published: February 2022

In this research work, an attempt is made to optimize the parameters of double pulse resistance spot welding process of AISI 409M ferritic stainless steel sheets by multi objective Taguchi approach. The tensile shear strength of the weld joint and indentation at the weld surface are taken as the response quality characteristics, which are required to be maximized and minimized respectively. Three control parameters, such as second pulse current, second pulse weld time and cooling time were taken for the analysis. Furthermore, a linear response surface model has been developed to correlate tensile shear strength and indentation values with process parameters. The results showed that, the second pulse current value was found to be the most influential parameter affecting tensile shear strength and indentation in double pulse resistance spot welding. Results of the optimization process were also validated by confirmation test.
Electrical Properties of WSe2-X Single Crystals Grown By Direct Vapour Transport Technique
Authors:   Sheth P. T. Arts and Science College, Godhra, Dist. Panchmahal, Gujarat, India 389 001, Vaidya Rajiv , Dave Mehul ,   N. V. Patel Pure and Applied Science College, Vallabh Vidyanagar, Gujarat, India 388 120, Patel Kaushik R ,   Biogas Research and Microbiology Department, Gujarat Vidyapith, Sadra, Gujarat, India 382320
Published: February 2022

The single crystals of WSe2-x were grown by direct vapour transport technique. The grown crystals possess hexagonal crystal structure. The resistivities of the as grown crystals were measured using van der Pauw method. The Hall parameters of the grown crystals were determined at room temperature from Hall effect measurements. Electrical resistivity measurements were performed on this crystal in the temperature range 303–423 K. The crystals werefound to exhibit semiconducting nature in this range. The activation energy and anisotropy measurements were carried out for this crystal. The value of resistivity is increases with increasing selenium content. The results obtained are discussed in detail.
Experimental Reduction of Condenser Exit Temperature in VCR System with Condenser Jacket
Authors:   Assistant Professor, Department of Mechanical Engineering, P V P Siddhartha Institute of Technology, Kanuru, Vijayawada, Andhra Pradesh, India., Anusha Dr.P , Naga Swapna Sri Dr.M ,   Assistant Professor, Department of Mechanical Engineering, P V P Siddhartha Institute of Technology, Kanuru, Vijayawada, Andhra Pradesh, India., Sravani V ,   Assistant Professor, Department of Mechanical Engineering, P V P Siddhartha Institute of Technology, Kanuru, Vijayawada, Andhra Pradesh, India.
Published: February 2022

The Air Conditioner’s condenser chamber releases hot air into the environment which leads to increase in temperature which has a great impact on the environment. The exhaust air produced in the air conditioner was hot air, which led to an increase in global warming and a decrease in the ozone layer. The role of the Condenser jacket is to cool down the hot air that released from the condensers outlet unit. The mud glass and dry grass inserted in the aluminium mesh which absorbs the hot air with the help of water. So the hot air turns to cold and leads to a reduction in global warming due to waste heat. We aim to develop a condenser jacket that will be fitted to the air conditioner condenser resulting in a reduction in the air temperature generated from the condenser after the refrigeration process. The water coming from the air conditioner is made to flow through mud glass and dry grasses which are inserted in aluminium casing. So that the mud glass and dry grass became wet. Hot air passing through wet mud glass and grass gets cold in turn lowers the temperature of the exhaust air. The temperature of air released from condenser should be lowered by this component which would be installed infront of the condenser. The Change in temperature of the air is observed to be around 4°- 5° C which is dependent on the atmospheric weather conditions. So the temperature of the air from the condenser jacket outlet decreases which in turn contributes to lowering global warming to some extent.
THE IMPACT MECHANISM OF HUMAN ACTIVITIES OVER CLIMATE SUITABILITY BASED ON SOCIAL NETWORK DATA: EVIDENCE FROM CHINA
Authors: Ren Yujie , Tang Xiaolan , Guo Naijing , Du Mengge
Published: February 2022

The impact mechanism of human activities on climate suitability is critical for understanding the human-environment nexus. In this study, social network data from Sina Weibo Platform was collected to quantitatively examined the relationship between the seven major types of human activities and climate suitability. The results indicated that the impacts of entertainment, tourism and daily life related human activities on climate suitability are significant (p-value < 0.05). With one-unit (one check-in record/km2) increase of entertainment and tourism related human activities, the coverage rate of climate suitable zone and the length of climate suitable period increase by 0.003% and 0.026 months, respectively. In contrast, one-unit of increase of daily life activities made the Theil entropy index of climate inequity and the length of climate suitable period increase 0.00035 units and shorten 0.014 months, respectively. Moreover, the impact mechanism of human activities on climate suitability showed a significant spatial heterogeneity within regions at different economic level or topographical conditions, which could be explained by the discrepancy of environmental policies, urban form and urban ventilation channel design strategies in China. This work exhibited a further step to new possibilities in clarifying the climate effect of human activities using open-sourced social network data.
MeerKAT Primary-beam Measurements in the L Band
Authors: de Villiers Mattieu S. , Cotton William D.
Published: February 2022

Full-polarization primary-beam patterns of MeerKAT antennas have been measured in the L band (856–1711MHz) by means of radio holography using celestial targets. This paper presents the observed frequency-dependent properties of these beams and guides users of this 64 antenna radio telescope that are concerned by its direction-dependent polarization effects. In this work, the effects on the primary beams due to modeling simplifications, bandwidth averaging, gravitational loading, and ambient temperature are quantified within the half-power region of the beam. A perspective is provided on the level of significance of typical use case effects. It is shown that antenna pointing is a leading cause of inaccuracy for telescope users in the presumed beam shape, introducing errors exceeding 1% in power near the half-power point of beams, owing to a telescope pointing accuracy of σ ≈ 0.′6. Disregarding these pointing errors, variability in the Stokes I beam shape relative to the array average is most commonly around 0.3% in power; however, the impact above 1500 MHz is on average triple that of the lower half of the band. This happens because the proportion of higher-order waveguide modes that are activated and propagate is sensitive to small manufacturing differences in the orthomode transducer for each receiver. Primary-beam correction verification test results for an off-axis spectral-index measurement experiment are included.
Near-IR and X-Ray Variability of Cyg X-3: Evidence for a Compact IR Source and Complex Wind Structures
Authors: Antokhin Igor I. , Cherepashchuk Anatol M. , Antokhina Eleonora A. , Tatarnikov Andrey M.
Published: February 2022

We study near-infrared (JHK) and X-ray light curves of Cyg X-3 obtained with the 2.5 m telescope of the Caucasian Mountain Observatory of MSU SAI and collected from the RXTE ASM and MAXI archives. The light curves in the X-ray and IR domains are strongly affected by irregular variations. However, the mean curves are remarkably stable and qualitatively similar in both domains. This means that the IR flux of the system originates not only from the free–free radiation of the Wolf–Rayet (WR) wind but also from a compact IR source located near the relativistic companion. The shape of the mean X-ray and IR light curves suggest the existence of two additional structures in the WR wind—a bow shock near the relativistic companion and a so-called “clumpy trail.” Modeling of the mean X-ray and IR light curves allowed us to obtain important system parameters: the orbital phase of the superior conjunction of the relativistic companion ϕ
0 = −0.066 ± 0.006, the orbital inclination angle i = 29.°5 ± 1.°2, and the WR mass-loss rate

M

̇

=
(
0.96
±
0.14
)
×

10

−
5

M

⊙

yr

−
1

. By using relations between

M

̇

and the rate of the period change and between

M

̇

and the WR mass, we estimated the probable mass of the relativistic companion M
C ≃ 7.2 M
⊙, which points toward the black hole hypothesis. However, this estimate is based on the assumption of a smooth WR wind. Considering the uncertainty associated with clumping, the mass-loss rate can be lower, which leaves room for the neutron star hypothesis.
The Compactness of Galaxy Groups in the Sloan Digital Sky Survey
Authors: Zheng 郑 Yun-Liang 云亮 , Shen 沈 Shi-Yin 世银 , Feng 冯 Shuai 帅
Published: February 2022

We use an updated version of the halo-based galaxy group catalog of Yang et al., and take the surface brightness of the galaxy group (μ
lim) based on projected positions and luminosities of galaxy members as a compactness proxy to divide groups into subsystems with different compactness. By comparing various properties, including galaxy conditional luminosity function, stellar population, active galactic nuclei (AGN) activity, and X-ray luminosity of the intracluster medium of carefully controlled high (HC) and low compactness (LC) group samples, we find that group compactness plays an essential role in characterizing the detailed physical properties of the group themselves and their group members, especially for low-mass groups with M
h ≲ 1013.5
h
−1
M
⊙. We find that the low-mass HC groups have a systematically lower magnitude gap Δm
12 and X-ray luminosity than their LC counterparts, indicating that the HC groups are probably in the early stage of group merging. On the other hand, a higher fraction of passive galaxies is found in the HC group, which however is a result of systematically smaller halo-centric distance distribution of their satellite population. After controlling for both M
h and halo-centric distance, we did not find any differences in both the quenching fraction and AGN activity of the member galaxies between the HC and LC groups. Therefore, we conclude that the halo quenching effect, which results in the halo-centric dependence of a galaxy population, is a faster process compared to the dynamical relaxed timescale of galaxy groups.
Conditions for Direct Black Hole Seed Collapse near a Radio-loud Quasar 1 Gyr after the Big Bang
Authors: Overzier Roderik A.
Published: February 2022

Observations of luminous quasars and their supermassive black holes at z ≳ 6 suggest that they formed at dense matter peaks in the early universe. However, few studies have found definitive evidence that the quasars lie at cosmic density peaks, in clear contrast with theory predictions. Here we present new evidence that the radio-loud quasar SDSS J0836+0054 at z = 5.8 could be part of a surprisingly rich structure of galaxies. This conclusion is reached by combining a number of findings previously reported in the literature. Bosman et al. obtained the redshifts of three companion galaxies, confirming an overdensity of i
775 dropouts found by Zheng et al. By comparing this structure with those found near other quasars and large overdense regions in the field at z ∼ 6–7, we show that the SDSS J0836+0054 field is among the densest structures known at these redshifts. One of the spectroscopic companions is a very massive star-forming galaxy (

log

10

(



⋆

/

M

⊙

)
=

10.3

−
0.2

+
0.3

) based on its unambiguous detection in a Spitzer 3.6 μm image. This suggests that the quasar field hosts not one, but at least two rare, massive dark matter halos (

log

10

(



h

/

M

⊙

)
≳
12

), corresponding to a galaxy overdensity of at least 20. We discuss the properties of the young radio source. We conclude that the environment of SDSS J0836+0054 resembles, at least qualitatively, the type of conditions that may have spurred the direct collapse of a massive black hole seed according to recent theory.
Space Debris Automation Detection and Extraction Based on a Wide-field Surveillance System
Authors: Jiang Ping , Liu Chengzhi , Yang Wenbo , Kang Zhe , Fan Cunbo , Li Zhenwei
Published: February 2022

Wide-field telescopes with long exposure times have stronger space target detection capabilities. However, complex background sky conditions will still cause a series of difficulties in detecting space debris, such as a large number of star points, a large amount of noise, and the discontinuity and nonlinearity of the target. We propose a space debris automatic extraction channel with a high detection rate and low computational cost to solve these difficulties. We apply an improved median filter for noise elimination and then the double-structure morphological filter algorithm used to suppress the background of the star image to eliminate star points and noise. Then, the guided filter was used to eliminate residual noise, and star points were used to reduce the impact on the target. Finally, the improved Hough transform was also applied to detect the target in the image. Our automatic extraction algorithm is used in real astronomical star maps, including different orbiting satellites (star-tracking mode). These images were obtained by using a 280 mm diameter telescope, which was located in Changchun Observatory. The experimental results demonstrated the effectiveness of the extraction algorithm in this study. It can effectively detect and track space targets in a long-exposure wide-field surveillance system and has high positioning accuracy and low computational complexity, which solves the problem of space debris extraction under a complex background.
CWISE J014611.20–050850.0AB: The Widest Known Brown Dwarf Binary in the Field
Authors: Softich Emma , Schneider Adam C. , Patience Jennifer , Burgasser Adam J. , Shkolnik Evgenya , Faherty Jacqueline K. , Caselden Dan , Meisner Aaron M. , Kirkpatrick J. Davy , Kuchner Marc J. , Gagné Jonathan , Gagliuffi Daniella Bardalez , Cushing Michael C. , Casewell Sarah L. , Aganze Christian , Hsu Chih-Chun , Andersen Nikolaj Stevnbak , Kiwy Frank , Thévenot Melina ,   The Backyard Worlds: Planet 9 Collaboration
Published: February 2022

While stars are often found in binary systems, brown dwarf binaries are much rarer. Brown dwarf–brown dwarf pairs are typically difficult to resolve because they often have very small separations. Using brown dwarfs discovered with data from the Wide-field Infrared Survey Explorer (WISE) via the Backyard Worlds: Planet 9 citizen science project, we inspected other, higher-resolution, sky surveys for overlooked cold companions. During this process, we discovered the brown dwarf binary system CWISE J0146−0508AB, which we find has a very small chance alignment probability based on the similar proper motions of the components of the system. Using follow-up near-infrared spectroscopy with Keck/NIRES, we determined component spectral types of L4 and L8 (blue), making CWISE J0146−0508AB one of only a few benchmark systems with a blue L dwarf. At an estimated distance of ∼40 pc, CWISE J0146−0508AB has a projected separation of ∼129 au, making it the widest-separation brown dwarf pair found to date. We find that such a wide separation for a brown dwarf binary may imply formation in a low-density star-forming region.
Pseudidothea armata sp. n., a new isopod of the genus Pseudidothea (Crustacea, Malacostraca, Isopoda) from the Atlantic sector of the Southern Ocean
Authors: Noli Nicholas , Di Franco Davide , Schiaparelli Stefano , Brandt Angelika
Published: February 2022

In the framework of the British Antarctic Survey (BAS) Expedion JR 15005 SO-AntEco, held in February-March 2016, the South Orkney Islands seafloor was sampled in order to investigate the distribution and composition of benthic communities around the area.

A new species of the genus Pseudidothea Ohlin, 1901 is described from the Burdwood Bank area (South Orkney Islands). It has been collected during the SO-AntEco JR15005 RRS James Clark Ross expedition under the lead of the British Antarctic Survey (BAS). The new species, Pseudidothea armata sp. n., is very similar to P. scutata (Stephensen, 1947); however, it is characterised by peculiar supra-ocular spines and a different tubercular pattern. The study of the species of the Pseudidothea helps to better understand the diversity of the Pseudidotheidae in the Southern Ocean.
Two new species of Drymonia (Gesneriaceae) from Northwestern South America, including the discovery of the longest flower known in the genus
Authors: Clark John L. , Clavijo Laura
Published: February 2022

Two new species, Drymonia intermedia Clavijo & J.L.Clark, sp. nov. and D. longiflora J.L.Clark & Clavijo, sp. nov. (Gesneriaceae, Columneinae), are described from the western Andean slopes of Ecuador and Colombia. The new species are similar to D. fimbriata, D. laciniosa, D. macrophylla, and D. peponifera because of the facultative epiphytic habit, deeply serrate to laciniate calyx margins, and fleshy bivalved capsules with tardily dehiscent endocarps. Leaves with brochidodromous venation, narrowly elongate corolla tube, and laciniate calyx margins differentiate D. intermedia. The longest corolla of any known Drymonia (> 6.5 cm long) differentiates D. longiflora. Digital photographs, geographic distributions, and IUCN categories are provided for the new species.
Phylogenomics of paleoendemic lampshade spiders (Araneae, Hypochilidae, Hypochilus), with the description of a new species from montane California
Authors: Ciaccio Erik , Debray Andrew , Hedin Marshal
Published: February 2022

Hypochilus is a relictual lineage of Nearctic spiders distributed disjunctly across the United States in three montane regions (California, southern Rocky Mountains, southern Appalachia). Phylogenetic resolution of species relationships in Hypochilus has been challenging, and conserved morphology coupled with extreme genetic divergence has led to uncertain species limits in some complexes. Here, Hypochilus interspecies relationships have been reconstructed and cryptic speciation more critically evaluated using a combination of ultraconserved elements, mitochondrial CO1 by-catch, and morphology. Phylogenomic data strongly support the monophyly of regional clades and support a ((California, Appalachia), southern Rocky Mountains) topology. In Appalachia, five species are resolved as four lineages (H. thorelli Marx, 1888 and H. coylei Platnick, 1987 are clearly sister taxa), but the interrelationships of these four lineages remain unresolved. The Appalachian species H. pococki Platnick, 1987 is recovered as monophyletic but is highly genetically structured at the nuclear level. While algorithmic analyses of nuclear data indicate many species (e.g., all H. pococki populations as species), male morphology instead reveals striking stasis. Within the California clade, nuclear and mitochondrial lineages of H. petrunkevitchi Gertsch, 1958 correspond directly to drainage basins of the southern Sierra Nevada, with H. bernardino Catley, 1994 nested within H. petrunkevitchi and sister to the southernmost basin populations. Combining nuclear, mitochondrial, geographical, and morphological evidence a new species from the Tule River and Cedar Creek drainages is described, Hypochilus xomotesp. nov. We also emphasize the conservation issues that face several microendemic, habitat-specialized species in this remarkable genus.
Choix officiels et choix réels dans les politiques linguistiques israéliennes
Authors: Bourgeois-Gironde Sacha
Published: February 2022

L’arabe a perdu son statut de langue officielle en Israël en juillet 2018. C’est l’occasion de s’interroger sur les rapports, complexes, entre le statut officiel d’une langue, la réalité des politiques linguistiques – en particulier dans la sphère éducative – et les pratiques et attentes effectives des locuteurs. Dans le cas qui nous intéresse, la perte du statut de langue officielle ne change pas la situation, déjà ambiguë, dans laquelle se trouvait l’arabe depuis le mandat britannique ; ce qui peut expliquer le peu de mobilisation des premiers intéressés – les arabes israéliens – en opposition à cette perte symbolique de statut. Car, dans les faits, la vitalité de l’arabe israélien dépend de deux facteurs : un bilinguisme asymétrique généralisé (au sens où la population arabe parle hébreu dans une proportion et à un niveau de compétence bien plus élevé que la population juive israélienne ne parle arabe), et des efforts privés non négligeables, en marge du système éducatif, pour favoriser une éducation bilingue réellement symétrique. Dans un pays aussi segmenté, idéologiquement et linguistiquement, qu’Israël, il est intéressant de constater que la vitalité des langues (au-delà de l’hébreu restauré et privilégié depuis les débuts de l’État d’Israël, et de l’arabe, non favorisé mais largement vivant) déborde largement les cadres officiels.
Prononciation du coréen langue étrangère par des apprenants français dans l’enseignement supérieur
Authors: Kang Shin-Tae , Lee Kyung
Published: February 2022

Cette étude a pour but d’évaluer la prononciation du coréen langue étrangère par des apprenants français en contexte universitaire et de proposer des préconisations d’amélioration de l’enseignement de cette langue. Le test de prononciation mené sur 143 étudiants de licence a permis une collecte de données constituée d’enregistrements représentatifs des difficultés phonologiques du coréen. Il est apparu des lacunes de prononciation sur les consonnes et sur sept règles phonologiques majeures qu’ils semblent nécessaires de combler.
Injonction à l’intuitivité et disparition des textes dans l’exposition
Authors: de Bideran Jessica
Published: February 2022

La miniaturisation des outils numériques et l’augmentation de leurs capacités de stockage permettent désormais aux commissaires et responsables d’exposition de multiplier les contenus textuels et audiovisuels en les mettant à disposition dans ces appareils qui équipent le visiteur. Si l’augmentation informationnelle permise par ces équipements a déjà fait l’objet de commentaires, nous souhaitons poursuivre ces réflexions en les resituant dans l’idéologie de l’écriture multimédia, qui repose notamment sur la plénitude des contenus et une infinie possibilité d’accès. À partir d’un terrain particulier, nous nous interrogerons sur cette injonction à l’intuitivité du dialogue homme-machine qu’il nous semble pertinent de confronter au ressenti des publics.
Nouvelles figures de l’artiste et injonction à la professionnalisation. Les institutions culturelles à l’heure des dispositifs de formation intégrés : le cas de l’Académie de la Comédie-Française
Authors: Errecart Amaia , Fache Philippe
Published: February 2022

Institution emblématique du patrimoine théâtral français, la Comédie-Française est aujourd’hui amenée à s’inscrire dans un contexte de professionnalisation croissante des activités artistiques et culturelles, comme en témoigne la création en 2009 de l’Académie, dispositif de formation intégrée, alternant pratique théâtrale et formation à vocation professionnalisante. Mobilisant un corpus d’entretiens qualitatifs réalisés auprès des anciens académiciens, nous interrogeons les formes d’injonction à l’œuvre à un double niveau : celui de l’institution comme des professionnels-acteurs. Nous nous intéresserons tout particulièrement à la question de son appropriation, à la fois par l’institution Comédie-Française et par les Académiciens eux-mêmes, à l’évolution des représentations liées à la figure de l’artiste et aux mutations des identités professionnelles induites.