Judul: Water Level Review in Ciawi Dry Dam Planning in Bogor Regency West Java
Abstrak: Bendungan Ciawi dikategorikan sebagai bendungan kering karena tidak adanya area permanen untuk menahan air. Tujuan penelitian ini adalah menentukan debit banjir serta elevasi muka air banjir Sungai Ciliwung yang direncanakan dan menguji kesesuaiannya dengan elevasi puncak Bendung Ciawi. Curah hujan harian maksimum diperoleh menggunakan metode Log Pearson dan debit banjir rencana dianalisis menggunakan metode Haspers. Data curah hujan harian maksimum periode ulang seribu tahun sebesar 336 mm. Nilai D kritis uji Kolmogorov-Smirnov sebesar 0.248 lebih kecil daripada nilai D maksimumnya sebesar 0.09, sehingga data tersebut dapat diterima. Data debit banjir rencana periode ulang seribu tahun dihasilkan sebesar 411.91 m³/detik. Pendugaan profil menggunakan program HEC-RAS menghasilkan elevasi muka air banjir Sungai Ciliwung 532.76 mdpl. Elevasi puncak bendung 551 mdpl, dengan elevasi muka air banjir untuk debit kala ulang 1000 tahun 545.95 mdpl dan tinggi jagaan sebesar 1.66 m, sesuai dengan elevasi muka air banjir Sungai Ciliwung., The Ciawi Dam is categorized as a dry dam because there is no permanent area to keep water. The purpose of this study were to determine the Ciliwung River flood discharge and flood water level plan planned and to analyze the correlation with the Ciawi Dam peak elevation. The maximum daily rainfall was obtained using the Pearson Log method and the design flood discharge was analyzed using the Haspers method. The maximum daily ranfall data for a thousand year return period was 336 mm. The critical D value of the Kolmogorov-Smirnov test of 0.248 was smaller than the maximum D value of 0.09, so the data can be used. The planned flood discharge for a thousand year return period was 411.91 m³/s. The profile prediction using the HEC-RAS program resulted in the elevation of the Ciliwung river flood water level was 532.76 masl. The dam's peak elevation of 551 masl, with the elevation of the flood water level of a thousand year return period of 545.95 masl and the freeboard height of 1.66 m, were suitable with flood water level of Ciliwung River.
Keyword: bendungan Ciawi, curah hujan, debit banjir, muka air, Sungai Ciliwung, bendungan Ciawi, curah hujan, Sungai Ciliwung, debit banjir, muka air

Judul: Planned Flood Discharge Analysis and Efforts to Reduce Runoff in Ciherang Sub-watershed, Cisadane Watershed
Abstrak: Sub-DAS Ciherang memiliki tutupan lahan yang didominasi oleh sawah dan perkebunan yaitu sebesar 539.2 ha dan 464.18 ha serta curah hujan bulanan yang tinggi pada bulan November sampai dengan Maret. Penelitian ini bertujuan untuk melakukan analisis curah hujan rencana pada Sub-DAS Ciherang, menganalisis debit banjir rencana dan besarnya limpasan, serta menganalisis upaya-upaya apa saja yang dapat dilakukan untuk mencegah terjadinya banjir. Pengukuran debit puncak dan limpasan dilakukan dengan analisis hidrologi dimana dalam pengukuran curah hujan rencana digunakan metode Log-Pearson III dan dalam pengukuran debit puncak digunakan metode hidrograf satuan sintesis Nakayasu. Sub-DAS Ciherang memiliki rata-rata curah hujan harian maksimum sebesar 103.18 mm/tahun dengan curah hujan rencana yang dihitung berdasarkan metode Log-Pearson III dengan periode ulang 2, 5, 10, 25, 50, dan 100 tahun sebesar 93.33, 124.11, 148.17, 182.99, 212.44, dan 245.02 mm. Sub-DAS Ciherang memiliki debit puncak dengan periode ulang yang sama yaitu sebesar 41.38, 55.03, 65.69, 81.13, 94.19, dan 108.63 m3/detik. Besarnya rasio DRO (direct runoff) dengan curah hujan pada 2 kejadian hujan sebesar 16.8% dan 19.3%. Besarnya DRO tersebut menyebabkan ancaman banjir pada daerah hilir cukup besar sehingga diperlukan upaya untuk mencegah terjadinya banjir. Upaya-upaya pencegahan banjir dapat dilakukan dengan konservasi tanah dan air yang dapat dibagi menjadi tiga metode, yaitu secara mekanik, vegetatif, dan kimiawi. Kata kunci : analisis hidrologi, , debit puncak, limpasan, pencegahan banjir, The Ciherang sub-watershed has land cover which is dominated by rice fields and plantations, namely 539.2 ha and 464.18 ha as well as high monthly rainfall from November to March. This study aims to analyze the planned rainfall in the Ciherang sub-watershed, analyze the planned flood discharge and runoff size, and analyze the efforts that can be made to prevent flooding. Measurement of peak discharge and runoff is carried out by hydrological analysis where the Log- Pearson III method is used in the planned rainfall measurement and the hydrograph method of the Nakayasu synthesis unit is used in the measurement of peak discharge. The Ciherang sub-watershed has a maximum daily average rainfall of 103.18 mm / year with a planned rainfall calculated based on the Log- Pearson III method with a return period of 2, 5, 10, 25, 50, and 100 years of 93.33, 124.11, 148.17, 182.99, 212.44, and 245.02 mm. The Ciherang sub-watershed has a peak discharge with the same return period, namely 41.38, 55.03, 65.69, 81.13, 94.19, and 108.63 m3/s. The magnitude of the DRO (direct runoff) ratio with rainfall in 2 rain events is 16.8% and 19.3%. The amount of DRO threatens the threat of flooding in the downstream area which is quite large so that efforts are needed to prevent flooding. Flood prevention efforts can be carried out by conserving soil and water which can be divided into three methods, namely mechanical, vegetative, and chemical. Keywords: flood preventing, hidrology analysis, peak discharge, runoff
Keyword: flood preventing, hidrology analysis, peak discharge, runoff

Judul: Penapisan Inhibitor Tirosinase pada Empat Spesies Famili Asteraceae Chrysantemum morifolium R, Gerbera jamesonii A, Dahlia rosea Cav, dan Tagetes erecta.
Abstrak: The research was conducted to screen the potency of tyrosinase inhibitor from 4 species of Asteraceae family. The screening was performed on the leaves and flowers of Chrysantemum morifolium R, Gerbera jamesonii A, Dahlia rosea Cav, and Tagetes erecta. The samples were dried and then extracted with nhexane, ethyl acetate, and methanol. The inhibition activity was tested by a microplate reader spectrophotometer in 492 nm. The ethyl acetate extract of D. rosea Cav flower was the most potent tyrosinase inhibitor (IC50 for monophenolase 18.42 μg/mL and for diphenolase 687.79 μg/mL) compared with the other Asteraceae species. The most active essential oils as inhibitor of tyrosinase was obtained from T. erecta flower (IC50 for monophenolase 1882.62 μg/mL and for diphenolase 1884.33 μg/mL). Positive control used was kojic acid with IC50 value of 11.02 μg/mL for monophenolase and 84.19 μg/mL for diphenolase. Fractionation of the extract by preparative thin layer chromatography with chloroform as mobile phase gave 12 fractions. The most active fraction had IC50 of 5.55 μg/mL for monophenolase and 109.96 μg/mL for diphenolase, and was identified as flavonoid.
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