Penelitian ini bertujuan untuk mengetahui pengaruh kristalinitas terhadap stabilitas termal komposit termoplastis dengan pengisi silika xerogel. Polimer yang digunakan adalah polietilena glikol (PEG 4000) yang merupakan polimer termoplastis. Silika xerogel diekstraksi melalui proses alkali fusion. Silika xerogel yang didapatkan menunjukkan fasa amorf melalui X-Ray Diffraction (XRD). Silika xerogel ditambahakan ke dalam PEG 4000 dengan komposisi yang bervariasi, yaitu, 0, 5, 10, dan 20%. Penambahan silika xerogel menurunkan tingkat kristalinitas komposit karena PEG murni merupakan material semikristalin. Melalui analisis termal menggunakan Thermogravimetric Analysis (TGA), pengaruh kristalinitas komposit tampak jelas pada daerah sebelum polimer mengalami transisi leleh. Namun, pada daerah dekomposisi (T>400C), pengaruh kristalinitas pada komposit tidak ada lagi. Hasil ini sangat menarik dikarenakan massa dekomposisi akhir menunjukkan nilai yang sama dengan komposisi silika xerogel yang ditambahkan, misalnya pada penambahan 20%, massa yang tersisa setelah dekomposisi adalah 20,77982 %. Oleh karenanya, analisis kristalinitas sangat mendukung hasil analisis termal dengan TGA pada komposit. Kata kunci:deformasi kristalografi TGA silika xerogel

Passenger Car Equivalent (PCE) is a conversion factor of various types of vehicles compared to passenger cars or other light vehicles concerning their impact on traffic behavior. The PCE value used in calculating the performance of urban roads refers to  Manual Kapasitas Jalan Indonesia (MKJI 1997) as an Indonesian Highway Capacity Manual. There have been many changes in traffic behavior nowadays compared to in 1997. The calculation of the PCE MC value using the average time headway method does not match the actual conditions. Therefore, modifications are needed by calculating the vehicle dimension factors to obtain the PCE value. The result of the PCE MC calculation using the modified average time headway method shows 0.17. This value is smaller than the value of the PCE MC set by the MKJI 1997, which shows 0.25. Based on the analysis of traffic conditions for ten years, the DS value using the PCE MC according to the MKJI  1997 obtains DS>1. Meanwhile, the DS value calculated based on the corrected PCE MC has DS<1. The difference in the value of PCE MC has implications for road performance. As a result, it affects traffic maintenance management in the form of maintenance costs and decision-making.

Telah dilakukan eksperimen pada spesimen Batu Gamping untuk mengetahui sifat fisik dan mekanik. Pada percobaan ini digunakan metode non-destructive yaitu dengan menggunakan alat ultrasonik dan osiloskop. Hasilnya, alat ultrasonik dan osiloskop mampu dengan baik mengukur kecepatan gelombang P. Selain itu, penelitian ini juga meliputi pengukuran sifat fisik internal batuan seperti porositas dan densitas. Selanjutnya dilakukan perhitungan parameter-parameter mekanik Batu Gamping berdasarkan teori yang ada. Beberapa nilai parameter penting yang didapatkan antara lain Compressional Wave Modulus (M), Bulk Modulus (k), dan Shear Modulus (μ) adalah 58,72 GPa, 19,57 GPa, dan 29,36 GPa, berturut-turut.

Surabaya-Mojokerto toll road is the strategic linked of Surabaya with the cities on west area of East Java. It became a main national logistic route that also can increase the economic potential East Java. The vital aspects of the Surabaya-Mojokerto Toll Road need to be balanced with adequate services for toll road users. The purpose of this study is to improve the index value of toll road service using Customer Service Index (CSI) method. One of the main aspects that need to be considered is the satisfaction of toll road users so that the assessment of the services provided can be balanced. In this study, using a questionnaire method distributed online through the google form application. The respondents were addressed to users of the Surabaya-Mojokerto Toll Road within the last month. The questions in the questionnaire regarding to the Regulation of the Minister of Public Works and Public Housing Agency No. 16, 2014 by making several adjustments. According to the analysis results, it shows that the service level criteria for the toll road is "Satisfied" with a CSI value of 79.56. The pavement factor is the main factor that needs to be improved to increase the service value of the Surabaya-Mojokerto Toll Road.