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Book Review: Doing Ethnographic Research Online
No full textIn the field of consumer and marketing research, netnographies have become a widely accepted form of research. Our social worlds are going digital, with perhaps hundreds of millions of people interacting through various online communities and their associated cybercultures. Netnography is a form of ethnographic research adapted to the unique contingencies of computer-mediated social interaction. This book aims to provide a set of methodological guidelines, a disciplined approach to the culturally—oriented study of that technologically—mediated social interaction that occurs through the Internet and related information and communications technologies. The methods that these various fields have used to investigate these topics are still somewhat uncertain and in flux. Most of this type of work written after the term was coined uses the guidelines and techniques that have been published about the netnographic approach
Efektivitas Latihan Strokes dengan Shadow dan Audio Visual terhadap Akurasi Dropshot Bulutangkis
Get PDFDropshot is one of the trick techniques in badminton, a good dropshot direction falls behind the double line. In badminton athletes aged 11-12 years the dropshot accuracy is still not good, the shuttlecock often falls far from the net or behind the short serve line. Based on these observations, it is necessary to have a form of training to improve dropshot accuracy. This research was conducted with the aim of knowing the effectiveness of strokes training with shadows and audio visual on dropshot accuracy. This study uses a quasi-experimental method, the design used in this study is the Two Groups Pretest-Posttest Design. The research subjects consisted of 14 badminton athletes aged 11-12 years (7 athletes in group A and 7 athletes in group B). With the sampling technique using purposive sampling, data analysis in this study used the t test. The results of this study showed that group A had a significant effect of strokes training with shadow on dropshot accuracy, with an increase in dropshot accuracy of 23.09% compared to the results in group B strokes training with audio visual, the magnitude of the increase in dropshot accuracy was obtained by 16.77%. So it can be concluded that strokes training with shadow has a better effect on badminton dropshot accuracy for athletes aged 11-12 years.
Keywords: Strokes practice, Shadow, Audio Visual, Dropshot Accuracy, Badminton
Dropshot merupakan salah satu teknik tipuan pada olahraga bulutangkis, arah dropshot yang baik jatuh dibelakang garis ganda. Pada atlet bulutangkis usia 11-12 tahun akurasi dropshot masih kurang baik, shuttlecock sering jatuh jauh dari net atau di belakang garis serve pendek. Berdasarkan pengamatan tersebut perlu adanya bentuk latihan untuk meningkatkan akurasi dropshot. Penelitian ini dilakukan dengan tujuan untuk mengetahui efektivitas latihan strokes dengan shadow dan audio visual terhadap akurasi dropshot. Penelitian ini menggunakan metode eksperimen semu, desain yang digunakan dalam penelitian ini adalah Two Groups Pretest-Posttest Design. Subjek penelitian terdiri dari 14 orang atlet bulutangkis usia 11-12 tahun (7 atlet kelompok A dan 7 atlet kelompok B). Dengan Teknik pengambilan sampel menggunakan purpose sampling, analisis data dalam penelitian ini menggunakan uji t. Hasil penelitian ini menunjukan kelompok A secara signifikan ada pengaruh latihan strokes dengan shadow terhadap akurasi dropshot, dengan peningkatan akurasi dropshot sebesar 23,09% dibandingkan hasil pada kelompok B latihan strokes dengan audio visual besarnya peningkatan akurasi dropshot diperoleh sebesar 16,77%. Sehingga dapat disimpulkan bahwa latihan strokes dengan shadow memiliki pengaruh yang lebih baik pada akurasi dropshot bulutangkis untuk atlet usia 11-12 tahun.
Kata kunci: Latihan strokes, Shadow, Audio Visual, Akurasi Dropshot, Bulutangki
Studi Kelayakan Perlindungan Pesisir Berkelanjutan melalui Integrasi Pemecah Gelombang Bambu dan Budidaya Kerang Hijau
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One pressing issue posing a significant threat to the coastal ecosystem is abrasion. Therefore, it is imperative to implement an effective and stable coastal protection structure using readily available and cost-effective materials combined with green mussel cultivation to bolster economic benefits for the community. The methodology employed in this study encompasses the integration and analysis of secondary data and the collection of archival information. The findings indicate that the ecological conditions of the waters in Bedono Village, Sayung District at Demak Regency meet the necessary criteria for green mussel cultivation. Bamboo with a minimum length of 7.5 meters and a planting depth of 2 meters is utilized. Financially, this approach proves to be quite advantageous, yielding a Net Present Value (NPV) of Rp1,202,383 for the stake method of green mussel cultivation. The Net Benefit-Cost Ratio (Net B/C) for the stake method of green mussel cultivation is 1.20. Based on the NPV and Net B/C feasibility criteria, the stake method of green mussel cultivation is considered viable. This structural concept is evaluated as adhering to ecological principles across all its components.
Keywords: Abrasion, breakwater, green mussel, natural coastal protectionSalah satu permasalahan yang cukup berat dan mengancam ekosistem di wilayah pesisir adalah abrasi. Untuk itu diperlukan struktur pelindung pantai yang efektif dan stabil dengan material yang mudah dan murah dengan kombinasi sebagai budidaya kerang hijau untuk menambah nilai ekonomi untuk masyarakat. Metode yang digunakan dalam penelitian ini yakni dengan mengombinasikan dan menganalisis data sekunder serta pengumpulan data arsip. Didapatkan hasil bahwa kondisi ekologis perairan Desa Bedono, Kecamatan Sayung, Kabupaten Demak memenuhi syarat untuk dapat digunakan sebagai lokasi budidaya kerang hijau. Bambu digunakan dengan panjang minimal 7.5 meter dan kedalaman pemancangan 2 meter. Dari sisi kelayakan finansial cukup menguntungkan dengan nilai NPV pada usaha budidaya kerang hijau metode tancap sebesar Rp1,202,383. Nilai Net B/C pada usaha budidaya kerang hijau metode tancap sebesar 1.20. Berdasarkan kriteria kelayakan NPV dan Net B/C, usaha budidaya kerang hijau dengan metode tancap layak dijalankan. Konsep struktur ini dianggap memenuhi prinsip ekologi berdasarkan assessment pada setiap komponennya.
Kata-kata Kunci: Abrasi, pemecah gelombang, kerang hijau, pelindung pantai natura
Commuter Travelers Perception of Toll Roads During the Ramp Up Period in Indonesia
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Studies on the travelers’ perceptions to toll roads during the ramp-up period are still rare, whereas they are important to assess toll road investment. The paper aims to establish a first approach in modeling the perceptions of individual commuter travelers during the learning process and adaptation to newly operating toll roads. Particularly, efforts to identify the attitudes and behaviors of individual commuter travelers towards interurban toll roads that connect between developing agglomeration areas. The data is collected through revealed and stated preference surveys using a snowball sampling technique with social media applications. Then we develop a binary logit model to explore commuter travelers’ perceptions to toll road during ramp-up period, and the results indicate that when doing commuter travel activities prefer to use the toll road, with the attributes that most influence on decision making respectively, travel time, travel costs, toll gate distance, travel distance, traveler's age, scenic beauty and the frequency of using toll roads. The paper also showed that the positive preference of toll roads during the ramp-up period is not always related to traffic congestion such as in dense urban areas, the presence of sightseeing traffic is very potential.
Keywords: Route choice behavior, binary logit model, toll road, ramp-up period
Abstrak
Studi mengenai persepsi masyarakat terhadap jalan tol selama periode ramp-up masih jarang dilakukan, hal ini penting untuk menilai kelayakan investasinya. Makalah ini bertujuan untuk menetapkan pendekatan pertama dalam memodelkan persepsi individu pelaku perjalanan komuter selama periode tersebut sebagai proses belajar dan beradaptasi terhadap jalan tol yang baru beroperasi. Khususnya, upaya untuk mengidentifikasi sikap dan perilaku individu pelaku perjalanan terhadap jalan tol antar kota penghubung kawasan aglomerasi yang sedang berkembang. Pengumpulan data dilakukan melalui survei revealed dan stated preference dengan teknik bola salju (snowball sampling) yang menggunakan media sosial. Kemudian kami mengembangkan model logit-biner untuk mengeksplorasi persepsi penumpang komuter terhadap jalan tol pada periode ramp-up dan hasilnya menunjukkan bahwa ketika melakukan aktivitas perjalanan, pelaku perjalanan komuter lebih memilih menggunakan jalan tol dengan atribut yang paling berpengaruh terhadap pengambilan keputusan masing-masing adalah, waktu tempuh, biaya perjalanan, jarak gerbang tol, jarak tempuh, umur penumpang, keindahan pemandangan dan frekuensi penggunaan jalan tol. Makalah ini juga menunjukkan bahwa preferensi positif terhadap jalan tol pada periode ramp-up tidak selalu terkait dengan kemacetan lalu lintas seperti di wilayah perkotaan yang padat, keberadaan lalu lintas tamasya sangat potensial mempengaruhi.
Kata-kata kunci: Perilaku pemilihan rute, model logit-biner, jalan tol, periode ramp-u
Measuring Spatializing Inequalities of Transport Accessibility and Urban Development Patterns: Focus on Megacity Urbanization, Thailand
Get PDFThe metropolis of Bangkok is characterized as a primate city because of its role as the capital of Thailand. Its suburbanization spreads to five surrounding provinces. Compared to other provinces in Thailand, it has highly concentrated urban development, without disparity between urban and rural areas. Furthermore, the travel volume in Bangkok and its surrounding areas is the highest in the country, with the majority related to private vehicle usage. This is why Bangkok is ranked as the world’s most congested city. To solve this problem and sustain the urbanization of the capital, it is necessary to understand the urban development patterns in Bangkok and their associated factors in measuring the accessibility of transportation. This research applied factor analysis and cluster analysis to characterize the different district contexts of the Bangkok Metropolitan Region, by selecting the Bangkok Metropolitan Administration (BMA) as the capital city area and Pathum Thani Province as a suburbanized area. Consequently, their transport accessibility could be represented by the level of accessibility in terms of the inequalities in the existing transportation system. Furthermore, by clustering the districts according to their economic and social factors, the causes of these inequalities could be identified by spatializing and geographically highlighting them. These findings should be integrated into the urban planning and development policies to overcome urban development challenges and create a city with more accessible and affordable public transport opportunities
Study of A Delayed SIVA Within-Host Model of Dengue Virus Transmission
Get PDFDuring the process of immune response to the infection caused by dengue virus, antibodies are generated by plasma cells which are produced by B-cells. In some cases, it is observed that there is a delay in the production of plasma cells from B-cells which causes a delay in the immune response. We propose a SIVA within-host model of the virus transmission with delayed immune response to articulate the dynamics of the cell and virus population. The stability analysis of different equilibrium states is also studied. The basic reproduction number (BRN) of the model is computed using next generation matrix (NGM) method. The local stability analysis is discussed using the method of linearisation. The stability conditions of the equilibrium states are validated using the Li´enard - Chipart criterion. Hopf bifurcation analysis is carried out as the system has time lag in the immune response. Three equilibrium states, namely, virus free equilibrium state, endemic equilibrium state with and without immune response, have been observed. It has been found that the virus free equilibrium state is locally asymptotically stable if BRN is less than or equal to 1. Additionally, the conditions for the stability of the endemic equilibrium points are derived and elaborated. Numerical simulations for different values of time delay parameter τ are presented and illustrated using graphs. A Hopf bifurcation is observed if the delay parameter τ crosses a threshold value and then the system becomes unstable with periodic solution. To determine the relative importance of the model parameters to the virus transmission and prevalence, sensitivity analysis of the parameters is illustrated using graphs. Due to the time lag in the immune response, an increase in the virus growth is observed in large quantity. As a result, the infection spreads more quickly within the host
Analisis Dinamik Lebah Tanpa Sengat (Trigona sp.)
No full textTrigona sp. is a stingless bee species that is widely distributed in tropical countries. It has castes in thecolony, i.e. queen, worker, and male bee. Despite its size, Trigona sp. can produce high-quality commoditiessuch as honey, propolis, and bee pollen. However, it is a vulnerable species since it’s pretty easy to be predatedby several predators and has a relatively short lifespan. In addition, there are still few mathematical studiesthat discuss the population dynamics of Trigona sp. Thus, in this study, we construct a mathematical modelof the Trigona sp. population in the form of a dynamical system. The model is a nine-dimensional non-lineardifferential equation that is constructed based on the stages in the bee population, namely the stages of eggs,larvae, and adult bees from each colony except the queen colony. Coexistence analysis, stability of equilibria, and also the death parameter sensitivity analysis are carried out in two scenarios. The first scenario is a situation where none of the workers die so that the food supply at the larval stage is sufficient. Meanwhile, the second scenario is a more common situation where some worker bees die from exhaustion resulting in an insufficient food supply for the larvae stage. Stable coexistence of all sub-structures and structural dependence on the foraging behavior of the workers are shown. All the results will be presented in numerical simulation. From the results of the coexistence and stability analysis, bee farmers can maintain food availability by increasing the number of workers in a colony, or providing food sources with high contains nectar and propolis at a relatively close distance to reduce the death of worker bees.Trigona sp. merupakan spesies lebah tanpa sengat yang tersebar luas di negara-negara tropis. Spesies ini memiliki kasta dalam koloni, yaitu ratu, pekerja, dan lebah jantan. Terlepas dari ukurannya, Trigona sp. dapat menghasilkan komoditas berkualitas tinggi seperti madu, propolis, dan bee pollen. Namun, spesies ini rentan karena cukup mudah dimangsa oleh beberapa predator dan memiliki umur yang relatif singkat. Selain itu, masih sedikit kajian matematis yang membahas tentang dinamika populasi Trigona sp. Dengan demikian, dalam penelitian ini, kami mengkonstruksi model matematika dari populasi Trigona sp. dalam bentuk sistem dinamik. Model tersebut merupakan persamaan diferensial nonlinier berdimensi sembilan yang dikonstruksi berdasarkan tahapan dalam populasi lebah yaitu tahapan telur, larva, dan lebah dewasa dari setiap koloni kecuali koloni ratu. Analisis koeksistensi, stabilitas kesetimbangan, dan juga analisis sensitivitas parameter kematian dilakukan dalam dua skenario. Skenario pertama adalah situasi dimana tidak ada pekerja yang mati sehingga persediaan makanan pada tahap larva tercukupi. Sementara itu, skenario kedua adalah situasi yang lebih umum di mana beberapa lebah pekerja mati karena kelelahan sehingga pasokan makanan untuk tahap larva tidak mencukupi. Kemudian, akan ditunjukkan koeksistensi yang stabil dari semua sub-struktur dan ketergantungan struktural pada perilaku mencari makan oleh para pekerja. Semua hasil akan disajikan dalam simulasi numerik. Dari hasil analisis koeksistensi dan stabilitas, peternak lebah dapat menjaga ketersediaan makanan dengan menambah jumlah pekerja dalam satu koloni, atau menyediakan sumber makanan dengan kandungan nektar dan propolis yang tinggi pada jarak yang relatif dekat untuk mengurangi kematian lebah pekerja
Emerging Technologies in the Development of Metallic and Bimetallic Nanoparticles in the Last Decade: A Scientometric Analysis
Get PDFThe development of nanotechnology and nanomaterials has had an upward surge in recent years, not only because of the type of technology but also because of the unique properties and characteristics of nanomaterials. This growth motivated us to make an analysis of emerging technologies in the development of metallic, bimetallic, and metal-oxide nanoparticles covering a period of ten years, which have had a high impact on the development of different products applied to biomedicine, electronics, agriculture, energy, plastics, etc. This research found more than one and a half million scientific papers under the keyword ‘nanotechnology’ in the Scopus database. This article reports a scientometric analysis where aspects such as articles with the highest number of citations, countries with the highest production, representative institutions in the field, authors and the relation of citations, correlations between them, keyword analysis, as well as the most studied topics in this field were investigated. On the other hand, the number of patents produced was reviewed in a general way. The databases Scopus, Journal Citation Report, VOSviewer, and other computer tools were used for the analysis. The results showed the United States (17.3%) and China (15.3%) as the countries with the greatest impact on studying metallic and bimetallic nanoparticles, with a high correlation between different countries. It is worth highlighting the participation of India with 10.1% and more than twice as many scientific papers as Germany; in the case of patents, the United States and China accounted for 55.3% of the total patents
Pengaruh Penambahan Nano Silika terhadap Volumetrik dengan Metode Pemadatan Marshall dan Superpave pada Campuran Beraspal Ac-Wc
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Nanotechnology is an engineering technology on materials into atomic or molecular sizes. One of the unique properties of nanomaterials is that have a large surface fraction and high surface performance. This study aims to determine the effect of the addition of nanomaterials on hot mix asphalt (AC-WC). The nano material used is silica from Bangka Belitung quartz sand which is processed into nano silica by Balai Besar Keramik Bandung. The asphalt used in the mixture is asphalt pen 60/70 produced by Pertamina. Nano silica is used as a filler substitution so that is can reduce the asphalt content which could be seen from the optimum asphalt content value with mixed variations of 1%, 2%, 3% nano silica when compared to conventional asphalt mixtures. In addition, using different compactor has an effect on nano silika mixture asphalt density. It can be seen that density value from superpave gyratori compactor (SGC) is lower than marshall compactor. In addition, the difference in the compaction method also affects the number of void in mixture and specimen height.
Keyword: Asphalt mixture, asphalt content, filler, nanosilica.Abstrak
Nano teknologi merupakan suatu teknologi rekayasa pada material kedalam ukuran atom atau molekul. Salah satu sifat unik dari nano material yaitu memiliki fraksi permukaan yang cukup besar dan kinerja permukaan yang cukup tinggi. Penelitian ini bertujuan untuk mengetahui pengaruh dari penambahan nano material pada campuran aspal panas lapis aus (AC-WC). Material nano yang digunakan pada penelitian ini adalah material silika yang berasal dari pasir kuarsa Bangka Belitung yang kemudian diproses menjadi nano silika oleh Balai Besar Keramik Bandung.Aspal yang digunakan pada campuran adalah aspal pen 60/70 produksi Pertamina. Penggunaan material nano silika sebagai subtitusi filler dapat mengurangi penggunaan kadar aspal yang mana dapat dilihat dari nilai kadar aspal optimum yang dihasilkan pada campuran dengan variasi 1%, 2%, 3% nano silika jika dibandingkan campuran beraspal konvensional. Selain itu, penggunaan alat pemadat yang berbeda memberikan pengaruh terhadap kepadatan yang dihasilkan pada campuran dengan penambahan nano silika. Hal tersebut terlihat bahwa kepadatan yang dihasilkan oleh alat pemadat superpave gyratory compactor (SGC) menghasilkan kepadatan yang lebih kecil dibandingkan dengan alat pemadat marshall. Selain itu, perbedaan metode pemadatan juga turut mempengaruhi jumlah rongga yang terdapat didalam campuran beraspal dan juga tinggi yang dihasilkan pada benda uji.
Kata-kata Kunci: Campuran aspal, filler, kadar aspal, nanosilika