19 research outputs found
Mekanisme Reaksi Asam Borat Dengan Produk Radiolisis Akibat Radiasi Sinar- Pada Temperatur 25oc
Get PDFMEKANISME REAKSI ASAM BORAT DENGAN PRODUK RADIOLISIS AKIBAT RADIASI SINAR- PADA TEMPERATUR 25OC. Telah dilakukan simulasi yang bertujuan untuk memahami mekanisme reaksi antara asam borat (H3BO3) yang ditambahkan kedalam air pendingin primer PWR dengan produk radiolisis akibat radiasi dengan sinar- pada temperatur 25oC. Simulasi dilakukan dengan menggunakan perangkat lunak ‘Facsimile' yang berbasis kinetika reaksi yang berkelanjutan. Sebagai masukan adalah set reaksi kimia yang terdiri dari 61 jenis reaksi dengan konstanta kecepatan reaksinya, nilai-G spesi radiolisis akibat radiasi sinar-, laju dosis 10 dan 104 Gy/s, konsentrasi awal oksigen yang berhubungan dengan sistem aerasi (0,25M), deaerasi dan konsentrasi asam borat hingga konsentrasi 1M. Luaran di program berupa seri Perubahan konsentrasi vs waktu iradiasi. Data luaran kemudian diolah menggunakan perangkat pembuat grafik ‘Origin'. Validasi dilakukan dengan membandingkannya dengan hasil simulasi sebelumnya. Hasil validasi menunjukkan perbedaan yang tidak signifikan, sehingga diputuskan bahwa set reaksi sekarang adalah valid. Penambahan asam borat menekan konsentrasi oksigen secara signifikan. Hubungan kenaikan logaritmik penambahan konsentrasi H3BO3 vs produk oksigen menunjukkan hubungan linear yang menurun. Dari hasil simulasi dapat dipahami bahwa penambahan H3BO3 tidak hanya mengatur reaktivitas neutron pada temperatur 25oC tetapi juga memberikan imbas positif didalam menekan konsentrasi produk oksigen yang memegang peran penting di dalam proses korosi
Aplikasi Msc Patran Untuk Penentuan Rentang Maksimum Penyangga Pipa Primer Reaktor Ap1000
Get PDFAPLIKASI MSC PATRAN UNTUK PENENTUAN RENTANG MAKSIMUM PENYANGGA PIPA PRIMER REAKTOR AP1000. Penyangga pipa digunakan antara lain untuk menjaga agar pipa tidak membebani komponen dan mencegah terjadinya lendutan yang berlebihan. Penentuan posisi penyangga pipa ditetapkan oleh beberapa faktor, seperti adanya katup, adanya belokan pipa dan jarak antara dua komponen utama reaktor yaitu tangki reaktor dan pembangkit uap.Untuk transpor panas dari tangki reaktor ke pembangkit uap digunakan pipa hotleg. Tujuan penelitian ini adalah untuk dapat menentukan batas jarak penyangga yang baik dan sudut belok pipa pada pipa primer reaktor daya AP1000 berdiameter 37,5inchi diameter luar dan 31 inchi diameter dalam. Metode analisis yang digunakan adalah metode komputasi dengan pemodelan menggunakan software MSC Patran.Hasil perhitungan menunjukkan bahwa semakin jauh jarak penyangga pipa maka besar lendutan yang terjadi makin besar.Nilai maksimal yang cukup baik dan sesuai standar ASME adalah pada jarak 5 m dengan sudut belok pipa 45 derajat.Pada jarak tersebut defleksi maksimumyang terjadi sebesar 1.76 cm dan tegangan tekuk sebesar 2.06 MPa
The Strategy to Support HTGR fuels for The 10 MW Indonesia's Experimental Power Reactor (RDE)
Get PDFThe Indonesia’s 10 MW experimental power reactor (RDE) is developed based on high temperature gas-cooled reactor (HTGR) and the program of the RDE was firstly introduced to the Agency for National Development Planning (BAPPENAS) at the beginning of 2014. The RDE program is expected to have positive impacts on community prosperity, self-reliance and sovereignty of Indonesia. The availability of RDE will be able to accelerate advanced nuclear power technology development and hence elevate Indonesia to be the nuclear champion in the ASEAN region. The RDE is expected to be operable in 2022/2023. In terms of fuel supply for the reactor, the first batch of RDE fuel will be inclusive in the RDE engineering, procurement and construction (RDE-EPC) contract for the assurance of the RDE reactor operation from 2023 to 2027. Consideration of RDE fuel plant construction is important as RDE can be the basis for the development of reactors of similar type with small-medium power (25 MWe–200/300 MWe), which are preferable for eastern part of Indonesia. To study the feasibility of the construction of RDE fuel plant, current state of the art of the R&D on HTGR fuel in some advanced countries such as European countries, the United States, South Africa and Japan will be discussed and overviewed to draw a conclusion about the prospective countries for supporting the fuel for long-term RDE operation. The strategy and roadmap for the preparation of the RDE fuel plant construction with the involvement of national stakeholders have been developed. The best possible vendor country to support HTGR fuel for long-term operation is finally accomplished. In the end, this paper can be assigned as a reference for the planning and construction of HTGR RDE fuel fabrication plant in Indonesia.
Keywords: RDE, Indonesia, HTGR, fuel, strategy
Improving science achievement through teacher collaboration of effective teaching and assessment practices
No full textThesis (M.A., Education (Educational Leadership and Policy Studies))-- California State University, Sacramento, 2010.In an article published in Science Education, the author categorizes the need for science education in the ???macro-argument??? and ???micro-argument??? (Laugksch, 2000). The micro-level argument focuses on the benefits of scientific literacy to the individual. The macro-level arguments suggest that scientific knowledge of citizens is critical for nations to compete successfully in international markets. Despite the need for science literacy of all students, California is not demonstrating necessary growth as indicated by the National Assessment of Educational Progress (NAEP) science assessments. In 2005, Mississippi was the only state with fourth-grade students and eighth-grade students scoring lower on average than California (U.S. Department of Education [DOE], 2005).\ud
Statement of Purpose\ud
This study is designed to determine the best practices for raising the levels of science achievement for all students at a California public high school. Specific questions to be addressed are:\ud
1. How are public schools held accountable for the student learning of the California State Science Standards, Kindergarten through 12th grades?\ud
2. How do effective teachers use the state science standards to improve science literacy?\ud
3. How can assessments be used effectively to guide student achievement?\ud
4. Should collaborative teaching teams focus on common assessments, effective teaching practices or both?\ud
Methodology\ud
This study evaluates the rationale for science achievement and levels of achievement for K-12th grade students currently measured. Effective teaching strategies will be defined and explored in this research, with attention given to effective science teaching. Assessment practices will be studied from the literature and through comprehensive survey of teachers and students. Lastly, the effects of collaboration of teachers within Professional Learning Communities (PLCs) will be studied through the literature, through interview of science teachers at Whitney High School and a survey instrument.\ud
Conclusions and Recommendations\ud
The researcher concludes the most effective method for raising science achievement at a school site is for teachers to work collaboratively on both common assessments and effective teaching practices. This researcher provides recommendations for administrators and educators, which are relevant to the overall goal of raising student science achievement for all K-12th grade students in the State of California. The recommendations give directives for educational leaders at the State level, the local level and the site level, to effect change toward science literacy.Education (Educational Leadership and Policy Studies
Radiolysis of water at elevated temperatures—II. Irradiation with γ-rays and fast neutrons up to 250°C
No full textImproving science achievement through teacher collaboration of effective teaching and assessment practices
No full textIn an article published in Science Education, the author categorizes the need for science education in the "macro-argument" and "micro-argument" (Laugksch, 2000). The micro-level argument focuses on the benefits of scientific literacy to the individual. The macro-level arguments suggest that scientific knowledge of citizens is critical for nations to compete successfully in international markets. Despite the need for science literacy of all students, California is not demonstrating necessary growth as indicated by the National Assessment of Educational Progress (NAEP) science assessments. In 2005, Mississippi was the only state with fourth-grade students and eighth-grade students scoring lower on average than California (U.S. Department of Education [DOE], 2005). Statement of Purpose This study is designed to determine the best practices for raising the levels of science achievement for all students at a California public high school. Specific questions to be addressed are: 1. How are public schools held accountable for the student learning of the California State Science Standards, Kindergarten through 12th grades? 2. How do effective teachers use the state science standards to improve science literacy? 3. How can assessments be used effectively to guide student achievement? 4. Should collaborative teaching teams focus on common assessments, effective teaching practices or both? Methodology This study evaluates the rationale for science achievement and levels of achievement for K-12th grade students currently measured. Effective teaching strategies will be defined and explored in this research, with attention given to effective science teaching. Assessment practices will be studied from the literature and through comprehensive survey of teachers and students. Lastly, the effects of collaboration of teachers within Professional Learning Communities (PLCs) will be studied through the literature, through interview of science teachers at Whitney High School and a survey instrument. Conclusions and Recommendations The researcher concludes the most effective method for raising science achievement at a school site is for teachers to work collaboratively on both common assessments and effective teaching practices. This researcher provides recommendations for administrators and educators, which are relevant to the overall goal of raising student science achievement for all K-12th grade students in the State of California. The recommendations give directives for educational leaders at the State level, the local level and the site level, to effect change toward science literacy
Pemilihan Teknologi Desalinasi Nuklir di Provinsi Kalimantan Timur
Get PDFPEMILIHAN TEKNOLOGI DESALINASI NUKLIR DI PROVINSI KALIMANTAN TIMUR. Saat ini, kebutuhan listrik di Kalimantan Timur (Kaltim) meningkat dengan kecepatan 12% per tahun. Karena pasokan listrik yang dihasilkan PT. PLN meningkat 8,5% per tahun, maka mengakibatkan terjadinya krisis listrik di daerah tersebut. PLTN (Pembangkit Listrik Tenaga Nuklir) dapat merupakan salah satu alternatif untuk mengatasi masalah tersebut. Demikian pula halnya dengan ketersediaan air bersih, pasokannya juga lebih sedikit dari pada kebutuhan. Sehingga memerlukan suatu upaya yang serius. Desalinasi nuklir adalah suatu proses memisahkan garam terlarut dari air laut atau air payau, yang dikopel dengan PLTN untuk memproduksi air bersih. Ada beberapa jenis teknologi desalinasi yang umum digunakan di dunia, diantaranya MSF (Multi-Stage Flash Distillation), MED (Multi-Effect Distillation) and RO (Reverse Osmosis). Makalah ini menyajikan hasil studi suatu pemilihan teknologi desalinasi untuk memperoleh solusi yang optimal. Pemilihan dilakukan berdasarkan pada pertimbangan 13 parameter penting yang diperkirakan sangat berpengaruh dalam menentukan pemilihan teknologi desalinasi nuklir dengan faktor pembobotan yang mempunyai kisaran 1 sampai 4. Teknologi yang dipilih adalah yang mempunyai nilai bobot paling tinggi. Hasil studi memperlihatkan bahwa MED mempunyai nilai bobot yang paling tinggi yaitu 39, diikuti nilai bobot 36 untuk RO dan 33 untuk MSF. Karena diperlukan air dengan kualitas sekitar 1 ppm untuk memasok PLTN dan untuk memasok kebutuhan masyarakat diperlukan air dengan kualitas dibawah 1000 ppm maka sistem hibrid MED-RO merupakan pilihan optimum untuk memproduksi air bersih
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Concurrent Validity of the Wide Range Assessment of Memory and Learning and the Woodcock-Johnson Tests of Cognitive Ability-Revised with a Neurologically Compromised Pediatric Population
Get PDFThe Wide Range Assessment of Memory and Learning (WRAML) is a relatively new instrument used in the assessment of memory in children. The purpose of this study was to examine the validity of the WRAML by comparing the performance of children on both the WRAML and the Woodcock-Johnson Tests of Cognitive Ability- Revised (WJTCA-R). Subjects for the study were children in treatment for a brain tumor at a regional children's medical center. Fifty children participated in the study ranging from ages 6 to 17. A multiple regression analysis was conducted to determine which of four selected clusters from the WJTCA-R would have the highest correlation with the Verbal Memory Index (VERI) from the WRAML. The Short-Term Memory (GSM) cluster had the highest correlation ( r = .82) as predicted. A Pearson's product-moment correlational analysis was conducted between the Visual Processing (GV) cluster from the WJTCA-R and the Visual Memory Index (VISI) from the WRAML. GV was found to have a high positive correlation ( r = .63) with VISI. A similar analysis was conducted between the Long-Term Retrieval (GLR) cluster from the WJTCA-R and the Learning Index (LRNI) from the WRAML. GLR was found to have a high positive correlation ( r = .81) with LRNI. Finally, a correlational analysis was conducted between the Broad Cognitive Ability (BCA) scale from the WJTCA-R and the General Memory Index (GENI) from the WRAML. A high positive correlation ( r = .87) was found between these most global measures from the two batteries. The observed correlation between BCA and GENI was much higher than anticipated. The author concluded that neurological impairment had affected subject memory and intellectual functioning in similar ways. The results do not generalize to children who have not had similar decrements in cognitive functioning. Future research should establish a baseline correlation between the two instruments with a non-impaired population
