506 research outputs found

    Heat transfer rates for filmwise, dropwise, and superhydrophobic condensation on silicon substrates

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    Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2011.Cataloged from PDF version of thesis.Includes bibliographical references (p. 24).Condensation, a two-phase heat transfer processes, is commonly utilized in industrial systems. Condensation heat transfer can be optimized by using surfaces in which dropwise condensation (DWC) occurs, and even further optimized using superhydrophobic surfaces. For superhydrophobic condensation, a structured silicon surface with pillars 2.1 p.m tall, 200 nm in diameter, and a 400 nm pitch was tested. By removing noncondensable gases (NCG) from the system by means of a steam trap, the heat transfer rates of DWC and SHC were found to be greater than that of filmwise condensation (FWC) by a factor of 2, but indistinguishable from each other. The effect of NCG leads to a 5x reduction in heat transfer rates for both DWC and SHC. DWC heat transfer rates are as much as 50 kW/m 2 less than FWC at the same temperature difference, representing a 25% reduction. However, the SHC heat transfer rates remain above those of FWC by as much as 50 kW/m² at the same temperature difference, representing a 20% improvement. These studies suggest that SHC may be a useful passive method to improve condensation heat transfer rates in the presence of NCG. However, it remains to be seen if SHC can provide better heat transfer rates than DWC under saturated steam conditions.by Travis M. Hery.S.B

    Indigenous Forest Protection and Management by Traditional Communities in Papua, Indonesia

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    Adat is a custom or tradition that connotes discipline and has sanctions (Adat Law/Customary Law). Legal politics is meant a revival of custom, which is not tradition but traditionalism within the local context of Papuan Traditional Communities specific in Special Autonomy. It still exists Traditional Communities and its customary territory which includes indigenous forest, requires the Recognition, Protection and Management of Indigenous Forests by placing the Traditional Communities as its subject. The definition of indigenous forest is a state forest within the territory of traditional communities. Indigenous forest in the sense of state forest, does not negate the rights of traditional communities insofar as they still exist and are acknowledged to exist, so that traditional communities can conduct forest management and harvesting of forest products in accordance with local wisdom. However, in the management and utilization of indigenous forests, there are frequent conflicts, causing claims on the territory, either in groups, or individually. Conflict occurring in the forestry sector, in fact has become an obstacle indicator in the process of indigenous forest management, the conflict also resulted in legal uncertainty in business activities in the field of forestry and encourage indifference to the future of forest resources. Special autonomy of Papua in preamble states “The management and utilization of natural resources of Papua Province has not been used optimally to improve the living standard of indigenous people”. So that required protection and management of indigenous forest based on local wisdom, which ultimately can improve the welfare of traditional community of Papua. Keywords: Indigenous Forest, Legal Politic, Traditional Communit

    Peningkatan Keterampilan Sosial Melalui Penerapan Metode Pembelajaran Team Games Tournament (Tgt)

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    :The aim of this research is to know social skills improvement process of 2nd grade students of elemen-tary school Mangkubumen Kulon Number 83 Surakarta through the application of team games tournament (TGT) learning methods and to figure out to what extend the social skill improvement is. The method used in this research is an action research that refers to the models of Class Action Research of Kemmis and Mc. Taggart which includes four stages: planning, action, observation and reflection. This research consist of two cycles, each cycle consist of 6 meetings/actions. The data are analysed using quantitative and qualitative data. Quantitative data are analysed using descriptive statistics method by comparing the first and second cycle result. While the qualitative data are analysed using the data from the field notes and interviews during the research by this fol-lowing steps: data reduction, data display and data verification. The results of this research show that there is so-cial skills improvement through the application of team games tournament (TGT) learning methods, it can be proven by the average scores of social skills in the pre-action was 63.35%. And then in the first cycle it is in-creasing by 15.23% to become 78.58%. Furthermore, from the first cycle to the second cycle kinesthetic intelli-gence of children is increasing by 11.80% from 78.58% to become 90.37%. So the total increasing kinesthetic intelligence of children ranging from pre-action, the first cycle to the second cycle is 27.02%, increase from 63.35% to become 90.37%

    Distinguishing two morphologically similar species of Asteraceae using a chloroplast DNA marker

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    Synedrella nodiflora (L.) Gaertn and Calyptocarpus vialis Less are members of Asteraceae family that morphologically show high similarities. To genetically distinguish between them, a particular molecular marker should be employed. This study aims to present molecular comparison between both species using a chloroplast DNA marker, i.e. atpB – rbcL IGS. A pair of PCR universal primers was used to amplify the marker. Sequence alignment on the PCR products reveals longer S. nodiflora sequence in comparison to that of C. vialis. In addition, some transversions and transitions are also observed. This suggests that the two species exhibit considerable genetic difference despite their similar phenotypic appearanc

    Hubungan Bakat Dengan Prestasi Belajar Santri Di Tka/tpa Al Muhajirin Unit. 769 Palembang

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    Manusia mengenal “Empat Karunia Ilahi” (4 Human Endowment), atau bakat alami, yakni kesadaran diri, imajinasi, hati nurani, dan kehendak bebas. Dalam hal ini bakat merupakan interseksi dari faktor bawaan dan pengaruh lingkungan. Jadi apabila seseorang terlahir dengan suatu bakat khusus, jika dididik dan dilatih, bakat tersebut dapat berkembang dan dimanfaatkan secara optimal.          Pradigma tentang bakat sudah saatnya dirombak. Contoh konkret tersebut tak terkecuali juga melanda dunia pendidikan. Berapa persen siswa suatu sekolah punya kesempatan mengeksplorasi bakat-bakatnya. Paling-paling tak lebih dari 10 hingga 25 persen, selebihnya dipendam atau mengembangkan dengan cara sendiri yang belum tentu terarah dengan baik, hingga manfaatnya tidak terasa. Skripsi ini membahas tentang hubungan bakat dengan prestasi belajar santri di TKA/TPA Al Muhajirin Unit. 769 Palembang. Variabel dalam penelitian ini ada dua yaitu bakat (X) sebagai variabel bebas dan prestasi belajar (Y) sebagai variabel terikat. Dalam penelitian ini yang menjadi populasi adalah santri TKA/TPA Al Muhajirin Unit. 769 Al Muhajirin yang berjumlah 118 santri. Dalam pengambilan sampel ditentukan 40% dari populasi penelitian ini diambil sebanyak 46 santri dan dalam pengambilan sampel tersebut menggunakan tratifed random sample berdasarkan ciri-ciri yang telah ditetapkan peneliti. Metode pengumpulan data menggunakan analisis statistik untuk mengetahui bakat dengan prestasi belajar santri dan mencari hubungan menggunakan rumus person product moment. Hasil analisis data yaitu Hubungan bakat dengan prestasi belajar santri di TKA/TPA Al Muhajirin Unit. 769 Palembang “r”; df = N-nr = 46-2 = 44. Dengan memeriksa tabel nilai “r” product moment ternyata bahwa dengan df sebesar 44, pada taraf signifikansi 5% diperoleh rtabel = 0,297, sedangkan pada taraf signifikansi 1% diperoleh rtabel = 0,384. Maka dapat diketahui bahwa rxy lebih besar dari pada rtabel, baik pada taraf signifikansi 5% maupun pada taraf 1% atau 0,297 < 17,60> 0,384. Jadi Hipotesa Nol (Ho) ditolak. Berarti terdapat hipotesis alternatif (Ha) terbukti dapat diterima dan hipotesis nihil (Ho) ditolak artinya ada hubungan yang signifikansi antara bakat dengan prestasi belajar santri di TKA/TPA Al Muhajirin Unit. 769 Palembang

    Analisis Faktor Pendukung Kinerja Standar Pendidik terhadap Ketercapaian Indikator Sekolah Ramah Anak

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    Penelitian ini bertujuan untuk menganalisis ketercapaian indicator perolehan predikat sekolah ramah anak dilihat dari factor pendukung dari kinerja standar pendidik. Latar belakang dari penelitian ini pada perolehan status sekolah ramah anak ditingkat Nasional termasuk jenjang PAUD, salah satu dari indicator pencapaian predikat sekolah ramah anak tersebut adalah pada standar kinerja pendidik. Keberhasilan yang di peroleh TK Negeri Pembina Jebres ini dalam perolehan indicator kinerja ini menjadi daya tarik peneliti terutama pada stanadar kinerja pendidik. Metode penelitian ini mengunakan Kualitatif deskriptif yang pengumpulan datanya melalu angket, wawancara dan dokumentasi. Kesimpulan dari penelitian ini factor standar kinerja pendidik sangatlah mendukung dalam pencapain indicator sekolah ramah anak, karena guru berperan langsung sebagai yang terdepan untuk memenuhi hak anak dan perlindungan kepada anak serta pengembangan bakat minat anak
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