The earth-air heat exchanger (EAHE) is an air-conditioning device utilizing a heat exchange between the air in the room and the soil. This paper purpose to determine the EAHE performance with experimentally and simulation. The simulation used are transient CFD, turbulent and 3-dimensional. The ambient air was distributed to the pipes with the different velocity of 2 m/s and 3 m/s. It was found that the earth-air heating exchanger effectiveness at air velocity 2 m/s for testing was 0.84 while for theoretical of 0.97. The coefficient of performance (COP) of EAHE increase from 1.341 to 1.761 when the increasing air velocity from 2 m/s to 3 m/s. The COP value also increases from 1.473 to 2.278 at the increasing of air velocity from 2 m/s to 3 m/s. The average of the COP value of the simulation result of the incoming air velocity was 1.99422 for velocity 3 m/s and 1.41426 for the velocity 2 m/s. For the average effectiveness of the simulation result obtained 1.00074 for the velocity of 3 m/s and 0.86100 for velocity 2 m/s.

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Kota besar di Indonesia, seperti Jakarta, Surabaya, Semarang dan Medan terancam terhadap banjir rob, khususnya di wilayah utara yang berbatasan langsung dengan perairan laut. Ratusan warga di kawasan utara Medan mengalami banjir rob akibat pasang air laut yang merendam permukiman mereka. Perlunya memetakan zona terancam banjir rob berdasarkan faktor-faktor penyebab banjir rob di wilayah Medan Utara sebagai dasar bagi pemangku kepentingan terkait dalam rangka penanganan untuk mengurangi kerugian akibat banjir rob. Faktor kerawanan terhadap banjir rob mencakup data curah hujan, drainage density, land use (tata guna lahan), jarak ke sungai, jenis tanah, elevasi, kemiringan, aspek, jarak ke muara. Analisis kuantitatif terhadap data dilakukan menggunakan Geographic Information System (GIS) dan Artificial Neural Network. Lokasi penelitian adalah Kecamatan Medan Belawan, Marelan dan Medan Labuhan Kota Medan. Hasil penelitian dengan rumus MAPE menunjukkan akurasi data train percobaan 1 sebesar 64,54137% dan data tes percobaan 1 sebesar 71,0257%. Sementara data train percobaan 2 sebesar 71,0257% dan data tes percobaan 2 sebesar 45,67167%. Akurasi data train percobaan 2 menggunakan rumus nilai eror < 1,5 sebesar  92% dan data tes percobaan 2 sebesar 68,61%.