Judul: Public loss value estimation caused by  traffic jam  (case:  simpang  pasar  parung,  kabupaten  Bogor)
Abstrak: Jumlah kendaraan bermotor yang terus meningkat dan perilaku pelanggaran aturan fungsi jalan yang dilakukan supir angkutan kota dan pedagang kaki lima (PKL) menyebabkan kemacetan lalu lintas di Parung. Kemacetan sebenarnya memberikan kerugian yang berdampak pada kondisi sosial, ekonomi, dan lingkungan bagi supir angkutan kota dan PKL. Penelitian ini menggunakan analisis deskriptif kualititatif dan kuantitatif, loss of earning, Contingent Valuation Method (CVM), dan regresi linear berganda. Metode pengambilan sample menggunakan purposive sampling. Berdasarkan hasil penelitian, kemacetan di Parung mengakibatkan supir angkutan kota dan PKL merasakan waktu terkuras, stres, penghasilan hilang, dan terganggunya kondisi lingkungan (polusi udara, suara, dan lingkungan). Pemborosan bensin hanya dirasakan oleh supir angkutan kota. Total kerugian ekonomi akibat kemacetan di Parung per hari yaitu sebesar Rp 154.126.360,00, per bulan sebesar Rp 4.623.790.790,00, dan per tahun sebesar Rp 55.485.489.478,70. Penggunaan metode CVM menghasilkan nilai rata-rata WTP yang diekspresikan responden, untuk supir angkutan kota sebesar Rp 4.881,00 per hari dan sebesar Rp 5.096,16 per hari untuk PKL., he increasing number of motor vehicles and indiscipline behaviour which are done by public transport drivers and street vendors (PKL) causes a traffic jam in Parung. Traffic jam actually give some losses for social, economic, and environment condition of public transport drivers and PKL. This research uses qualitative descriptive and quantitative analysis, loss of earning method, Contingent Valuation Method (CVM), and multiple linear regression. Samples took by purposive sampling. Based on research results, traffic jam in Parung made public transport drivers and PKL times wasted, stressed, loss of earning, and disruption of environmental (air, noise, and environmental pollution). Wasted BBM only experienced by public transport drivers. Total loss economics causes traffic jam in Parung is IDR154,126,360.00 per day, IDR4,623,790,790.00 per month, and IDR55,485,489,478.70 per year. The uses of CVM method results WTP average value which is expressed by respondents, with amount IDR4,881.00 per day for public transport drivers and IDR5,096.00 per day for PKL.
Keyword: Kemacetan, kerugian, sosial-ekonomi-lingkungan, willingness to pay  (WTP)

Judul: Estimating the Value of Road User Losses due to  Traffic Congestion on Dramaga Highway, Bogor Regency
Abstrak: Jalan Raya Dramaga merupakan salah satu jalur yang memiliki intensitas kemacetan yang tinggi di wilayah Bogor. Kemacetan di Jalan Raya Dramaga berpotensi berdampak pada aspek sosial, ekonomi, dan lingkungan bagi pengguna jalan dan wilayah sekitar. Solusi pemecahan kemacetan di Jalan Raya Dramaga menjadi penting untuk segera dilakukan. Penelitian ini bertujuan untuk menganalisis dampak sosial, ekonomi, dan lingkungan yang dirasakan oleh pengguna jalan akibat kemacetan lalu lintas di Jalan Raya Dramaga, menghitung besarnya pengeluaran BBM pengguna jalan akibat kemacetan di Jalan Raya Dramaga, serta menghitung besarnya penghasilan yang hilang bagi pengguna jalan akibat kemacetan di Jalan Raya Dramaga. Metode analisis yang digunakan dalam penelitian ini, yaitu analisis deskriptif kualitatif dan kuantitatif, perhitungan rata rata, serta penghasilan hilang (loss of earning). Hasil penelitian menunjukkan, dari sisi sosial kemacetan di Jalan Raya Dramaga memberikan dampak negatif bagi pengguna jalan, yaitu terganggunya interaksi sosial dan produktivitas, terbuangnya waktu kerja, menimbulkan stres, serta peningkatan emosi. Dari sisi ekonomi, kemacetan di Jalan Raya Dramaga menyebabkan terjadinya kerugian inefisiensi bahan bakar sebesar Rp6.693.376.320 per tahun dan menyebabkan penghasilan yang hilang sebesar Rp41.128.889 per tahun, selain itu pengguna jalan secara umum mengalami penurunan waktu kerja. Dari sisi lingkungan, kemacetan di Jalan Raya Dramaga dinilai menimbulkan polusi lingkungan, polusi udara (udara kotor), polusi suara (kebisingan), peningkatan suhu, dan masalah kebersihan lingkungan., Jalan Raya Dramaga was one of the routes that experienced high traffic congestion in the Bogor area. The congestion on Jalan Raya Dramaga had the potential to impact social, economic, and environmental aspects for road users and the surrounding area. Finding a solution to the traffic congestion on Jalan Raya Dramaga became crucial and needed immediate attention. This research aimed to analyze the social, economic, and environmental impacts experienced by road users due to traffic congestion on Jalan Raya Dramaga, calculate the amount of fuel expenses incurred by road users due to congestion on Jalan Raya Dramaga, and determine the extent of income loss for road users due to congestion on Jalan Raya Dramaga. The research utilized qualitative and quantitative descriptive analysis methods, average calculations, as well as loss of earning calculations. The research findings revealed that from a social perspective, traffic congestion on Jalan Raya Dramaga had negative impacts on road users, disrupting social interactions and productivity, wasting work time, causing stress, and escalating emotions. Economically, the congestion on Jalan Raya Dramaga led to fuel inefficiency losses amounting to IDR 6.693.376.320 per year and resulted in an income loss of IDR 41.128.889 per year, in addition to a general decrease in work hours for road users. From an environmental standpoint, traffic congestion on Jalan Raya Dramaga was considered to contribute to environmental pollution, air pollution (dirty air), noise pollution (noise), temperature rise, and environmental cleanliness issues.
Keyword: Dampak sosial-ekonomi-lingkungan, Kemacetan, Loss of Earning, Perhitungan rata-rata kerugian

Judul: Hydroxyapatite-Chitosan Composite Coating on Stainless Steel 316 to Improve Corrosion Resistance
Abstrak: Metals that were used in bone implantation should have good corrosion resistance that were not easily corroded when implanted into the body. Metal corrosion resistance of stainless steel 316 can be enhanced through the metal coating by hydroxyapatite-chitosan composite with composition ratio of hydroxyapatite (gram) and chitosan 3% (mL) 0.2:0, 0.2:0.1, 0.2:0.5, 0.2:1.0, and 0.2:1.5. Besides improving the corrosion resistance of metal, the presence of chitosan also maintain the position of hydroxyapatite on metal surfaces. Corrosion resistance increases with increasing amount of chitosan added and the best composition of hydroxyapatite-chitosan composite was 0.2:1.0.
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