Luthfi Pratama
Physical Chemistry Laboratory, Chemistry Department, Faculty of Mathematics and Natural Sciences, Universitas Gadjah Mada, Sekip Utara, Yogyakarta 55281

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ANALISIS PEMBENTUKAN PORTOFOLIO SAHAM OPTIMAL MENGGUNAKAN METODE SINGLE INDEX MODEL (Studi Empiris pada Saham Indeks LQ 45 di Bursa Efek Indonesia) Pratama, Luthfi
JURNAL ILMU MANAJEMEN Vol 16, No 1 (2019)
Publisher : Universitas Negeri Yogyakarta

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (448.634 KB) | DOI: 10.21831/jim.v16i1.25064

Abstract

Penelitian ini bertujuan untuk mengetahui komposisi portofolio optimal saham,  besarnya proporsi dana serta return dan risiko pada masing-masing saham tersebut menggunakan metode Single Index Model. Populasi dalam penelitian ini adalah seluruh saham yang termasuk dalam indeks LQ-45 yang terdaftar di Bursa Efek Indonesia Periode Agustus 2016 - Agustus 2018. Sampel penelitian ditentukan menggunakan metode purposive sampling dengan kriteria saham perusahaan terdaftar secara konsisten dalam indeks LQ-45 selama periode Agustus 2016 - Agustus 2018. Hasil penelitian menunjukkan bahwa: (1) terdapat tujuh saham yang termasuk dalam portofolio saham optimal menurut Single Index Model yaitu INCO (Vale Indonesia Tbk.), SRIL (Sri Rejeki Isman Tbk.), BBRI (Bank Rakyat Indonesia (Persero) Tbk.), BMRI (Bank Mandiri (Persero) Tbk.), BBNI (Bank Negara Indonesia (Persero) Tbk.), BBTN (Bank Tabungan Negara (Persero) Tbk.), dan GGRM (Gudang Garam Tbk.). (2) Besarnya proporsi dana yang layak diinvestasikan pada saham tersebut adalah INCO sebesar 14,56%, SRIL sebesar 11,11%, BBRI sebesar 22,01%, BMRI sebesar 19,05%, BBNI sebesar 15,08%, BBTN sebesar 7,63%, dan GGRM sebesar 10,53%. (3) Return dari portofolio saham optimal yang telah terbentuk adalah sebesar 1,50% per bulan, sedangkan risiko yang harus ditanggung investor dari portofolio saham optimal tersebut sebesar 0,85%.
EFFECT OF TEMPERATURE AND SPEED OF STIRRER TO BIODIESEL CONVERSION FROM COCONUT OIL WITH THE USE OF PALM EMPTY FRUIT BUNCHES AS A HETEROGENEOUS CATALYST Pratama, Luthfi; Yoeswono, Yoeswono; Triyono, Triyono; Tahir, Iqmal
Indonesian Journal of Chemistry Vol 9, No 1 (2009)
Publisher : Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (779.06 KB) | DOI: 10.22146/ijc.21562

Abstract

Biodiesel synthesis by transesterification reaction of coconut oil with methanol by using ash of palm empty fruit bunches (EFB) as base catalyst has been conducted. Sample of ash was prepared through heating, screening, reashing, and finally determining of potassium content. Sample of coconut oil was analyzed by GC-MS. A certain amount of ash was extracted in methanol with mixing for about 1 h at room temperature and a result was used for reaction of transesterification. The studied variables were effect of temperature and speed of stirrer. The composition of the methyl esters (biodiesel) was analyzed using GC-MS and 1H NMR, whereas characters of biodiesel were analyzed using ASTM methods. The results showed that potassium content in ash of EFB could be extracted by methanol and it could be used as base catalyst in the biodiesel synthesis. The value increasing of both variables enhanced the biodiesel conversion. The properties of biodiesel were relatively conformed to specification of biodiesel.   Keywords: biodiesel, coconut oil, base catalyst, temperature, stirring
PENGARUH DOSIS VAKSIN NEWCASTLE DISEASE INAKTIF PADA ITIK BETINA TERHADAP JUMLAH SEL DARAH PUTIH DAN TITER ANTIBODI Pratama, Luthfi; Santosa, Purnama Edy; ., Siswanto
JURNAL ILMIAH PETERNAKAN TERPADU Vol 4, No 3 (2016)
Publisher : DEPARTMENT OF ANIMAL HUSBANDRY, FACULTY OF AGRICULTURE, UNIVERSITY OF LAMPUNG

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (211.68 KB) | DOI: 10.23960/jipt.v4i3.p%p

Abstract

This study are determines to: 1) the effect of ND vaccine dose to the number of white blood cells produced in the female ducks; 2) the effect of ND vaccine doses to the amount of antibody titers produced in the female ducks. This research was conducted in December 2015 until January 2016, located in the Sabah Balau, District of Tanjung Bintang, South Lampung regency. Analysis of white blood cells (WBC) conducted in the Central Veterinary of Lampung, while the number of antibody titer was conducted in PT. Vaksindo, Jakarta. The experimental design used in this study is completely randomized design with three replications and 6 treatments (P0: injected 0.5 ml of distilled water, P1: 0.1 ml of ND inactivated vaccine doses, P2: 0.2 ml of ND inactivated vaccine doses, P3: 0.3 ml of ND inactivated vaccine doses, P4: 0.4 ml of ND inactivated vaccine doses, P5: 0.5 ml of ND inactivated vaccine doses). The treatment given to 5 days old female ducks with inactivated ND vaccine.  White blood cells are tested by using the WBC test while antibody titers were tested by using the HI test.  The data result were analyzed by ANOVA at 5% significance level and will be continued by Least Significant Difference (LSD) in white blood cells because the value of analysis of variance showed tangible results. The results of this study showed that giving of inactivated ND vaccine doses significantly (P <0.05) to the number of white blood cells, but did not significantly affect (P> 0.05) titer of antibodies. Keywords: Antibody Titer, Female Ducks, Inactivated ND Vaccine, White Blood Cells