Judul: Faktor-Faktor Sosial Ekonomi yang Mempengaruhi Fertilitas Perempuan dengan Lama Perkawinan di Bawah 10 Tahun di Provinsi Jawa Barat
Abstrak: The high rate of population growth is the main problem faced by the development of developing countries, including Indonesia. Population explosion occurred mainly due to a decreased level of mortality (death) while the population fertility rates can not be well controlled. The purpose of this study was to determine the socio economics factors that affect fertility (births) in the Province of West Java. Information factors can be used as one tool in population control considerations. This study used the data of National Socio economic Survey of West Java Province in 2011. Response variable in this study is the number of biological children born alive, whisch is continuous, so that the proper analysis is a regression tree with CART algorithm. Regression tree in urban produce 6 end nodes with the most effective explanatory variable is the contraception status, husband’s education, expenditure per capita per month, and the use of toilet. Regression tree in rural produce 5 end nodes with the most effective explanatory variable is the status of the use of family planning, expenditure per capita per month, and the use of toilet.
Keyword: regression tree, fertility, CART

Judul: Analisis Regresi Dalam Menentukan Faktor-Faktor Yang Mempengaruhi Fertilitas di Indonesia
Abstrak: Penelitian ini bertujuan untuk mempelajari keterkaitan tingkat fettilitas dengan tingkat pendidikan, mortalitas anak, umur kawin pertama, jumlah akseptor, faktor lingkungan dan pendapatan dengan menggunakan model regresi. Data yang digunakan berupa data setiap propinsi yang berasal dari SENSUS PENDUDUK 1980 dan PENGHITUNGAN PENDAPAT- AN REGIONAL. Pola hubungan antar peubah dilakukan dengan analisis regresi, sedangkan pemeriksaan korelasi spasial menggunakan statistik Join Count. Model regresi yang diperoleh menunjukkan adanya hubungan antara tingkat fertilitas dengan mortalitas anak dan hasil analisis sisaan menunjukkan adanya korelasi spasial antar propinsi yang berdekatan. Dengan mengidentifikasi propinsi Sumatera Utara, Nusa Tenggara Barat, Sulawesi Utara dan Irian Jaya sebagai data pencilan dan menyisihkan ke empat daerah tersebut., diperoleh model regresi : Fertilitas = 3,70 + 4,01 mortalitas anak + 1,97 umur kawin pertama 3,14 akseptor. Model regresi ini memiliki koefisien diterminasi, R sebe- sar 0.789 dan berhasil meniadakan korelasi spasial antar propinsi yang berdekatan. Tingginya mortalitas anak, meningkatkan fertilitas sedang jumlah akseptor yang menaik, menurunkan fertilitas. Pengaruh positif umur kawin pertama terhadap fertilitas, disebabkan oleh banyaknya wanita yang memulai masa repro- duksi pada usia muda di setiap propinsi dengan kisaran umur antara 15 sampai 19 tahun. Adanya korelasi spasial pada sisaan regresi model yang pertama disamping disebabkan oleh hubungan propinsi yang berdekatan, kemungkinan juga karena adanya data pencilan pada beberapa daerah. Penelitian ini masih mengandung kelemahan, salah satunya adalah karena faktor lamanya kawin belum diperhi- tungkan. Untuk penelitian lebih lanjut, disarankan menambah peubah lamanya kawin di dalam model regresi tersebut.
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Judul: Characterizations of low alloy steel sae 4422  plated with chromic acid (Cro3)
Abstrak: Characterizations of low alloy steel SAE 4422 plated with chromic acid (CrOrO3) was use Optical Microscopy (OM), Scanning Electron Microscopy (SEM), X-Ray Diffraction (XRD), RD),Energy Dispersive Analysis of X-Ray (EDAX), Hardness Test and Roughness Test. Microstructures analysis exhibits cracks and grain boundaries microcracks as a characteristics of chrome metal found at plating metal. Perlite and Ferrite as grains of steel found at base metal with grain boundaries around it. Phase analysis of plating metal appropriate to chrome metal with lattice constant (a) is 2.559 Å and phase analysis of base metal appropriate to iron ferrite with lattice constant (a) is 3.318 Å. Both plating and base metal have cubic system. Chemical analysis of plating metal at surface section exhibits that cracks area have highest value of carbon element compare with grains and grains boundaries area. While chemical analysis of base metal at cross section exhibits that perlite have highest value of carbon element compare with ferrite and grain boundaries. The hardness value of plating metal at surface section and cross section are 753 and 637 VHN. While, the hardness value of base metal and interface area at cross section are 205 and 373 VHN. The roughness value at measurement points of chrome surface for as received sample are 0.445 μm. Observation used Optical Microscopy and Scanning Electron Microscopy exhibits surface irregularities combine to form surface texture of plating metal at surface section.
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