DAFTAR PUSTAKA
Herjanto, Eddy. (2006) Manajemen Operasi Edisi Ketiga. Jakarta : PT. Gramedia Widiasarana Indonesia Rangkuti, Freddy. (2007) Manajemen Persediaan. Jakarta: PT RAJAGRAFINDO PERSADA Kusuma, Hendra. (2009) Manajemen Produksi Perencanaan & Pengendalian Produksi. Yogyakarta : ANDI Gaspers, Vincent. (2012) Production Planning and Inventory Control. Jakarta : Gramedia Pustaka Utama. Heizer, Jay. & Render, Barry Render. (2005) Manajemen Operasi Edisi Ketujuh Buku 2. Jakarta : Salemba Empat Haming, Murdifin. & Mahfud Nurnajamuddin. (2007) Manajemen Produksi Modern (Operasi Manufaktur dan Jasa). Jakarta : Bumi Aksara Sugiyono (2009) Metode Penelitian administrasi. Bandung : CV Alfabeta
Jurnal dan Skripsi : Sagbansua, Lutfu & M. Nurettin Alalabay. (2010). An MRP Model for Supply Chains. (School of Economics and Administrative Sciences, Turki) Oladokun, V.O & O.A Olaitan. (2012). Development of a Materials Requirements Planning (MRP) Software. (University of Ibadan, Nigeria) E.D, Dinesh & Arun A.P, Pranav R. (2014). Material Requirement Planning for Automobile Service Plant. (Kumaraguru College of Technology, India) Limbong, Inggried & H. Tarore, J. Tjakra, D. R. O. Walangitan. (2013). Manajemen Pengadaan Material Bangunan Dengan Menggunakan Metode MRP (Material Requirement Planning) Studi Kasus: Revitalisasi Gedung Kantor BPS Propinsi Sulawesi Utara. (Universitas Sam Ratulangi, Manado)
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Surianto, Agus. (2013). Penerapan Metode Material Requirement Planning (MRP) di PT. Bokormas Mojokerto. (Universitas Brawijaya, Malang) Ruhul Ummiroh, Isnaini. (2013). Analisis Penerapan Material Requirement Planning (MRP) Pada Pennyellow Furniture. (Universitas Jember, Jember) Dian Wijaya, Dilzar. (2006). Analisis Pengendalian Persediaan Bahan Baku Susu Kental Manis Pada PT. Indomilk. (Institut Pertanian Bogor, Bogor) Taryana, Nanang. (2008). Analisis Pengendalian persediaan Bahan Baku Pada Produk Sepatu Dengan Pendekatan Teknik Lot Sizing Dalam Mendukung Sistem MRP(Studi Kasus di PT. Sepatu Mas Idaman, Bogor). (Institut Pertanian Bogor, Bogor) Amalia, Alona. (2013). Analisa Pengendalian Persediaan Bahan Baku MCSET AD1 12.5 kV dengan Menggunakan Metode Forecast dan Material Requirement Planning di PT. Schneider Indonesia. (Universitas Mercu Buana, Jakarta) Irawan, Andy. (2014). Usulan Perencanaan Persediaan Bahan Baku Tinta Sakata dengan Menggunakan Metode Material Requirement Planning (MRP). (Universitas Mercu Buana, Jakarta) Agung S, Akbar. (2009). Penerapan Metode Single Moving Average dan Exponential Smothing Dalam Peramalan Permintaan Produk Meubel Jenis Coffe Table pada Java Furniture Klaten . (Universitas Sebelas Maret, Surakarta)
Website: http://bisnis.liputan6.com/read/2191512/2-perusahaan-telekomunikasi-merugi-garagara-penguatan-dolar-as ( diakses pada 10 Desember 2015) https://indosatooredoo.com/id/about-indosat/company-profile/history ( diakses pada 28 November 2015) http://taufiqurrachman.weblog.esaunggul.ac.id/wpcontent/uploads/sites/968/2013/10/EMA302-4-Peramalan-Forecasting-2-Exe.pdf ( diakses
pada 29 Maret 2016)
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LAMPIRAN Lampiran 1 : Perhitungan Peramalan
Bulan Januari Febuari Maret April Mei Juni Juli Agustus September Oktober November Desember Total
Produksi Aktual (A) 15,491,435 8,115,495 14,100,053 14,240,846 9,249,529 25,558,159 5,933,333 9,691,006 10,293,913 13,286,418 11,162,021 17,532,579 154,654,788
A. Perhitungan Peramalan Model Pemulusan Exponensial (Exponential Smoothing) dengan α = 0.1 = 15,491,435+ 0.1 (8,115,495 - 15,491,435)
F Januari ’15
= 14,753,841 F Febuari ’15
= 14,753,841 + 0.1 (15,491,435 - 14,753,841 ) = 14,827,600.5 = 14,827,601
F Maret ’15
= 14,827,601+ 0.1 (8,115,495 - 14,827,601) = 14,156,390.4 = 14,156,390
dan seterusnya.
64 http://digilib.mercubuana.ac.id/
65
B. Perhitungan Peramalan Model Pemulusan Exponensial (Exponential Smoothing) dengan α = 0.5 F Januari ’15
= 15,491,435+ 0.5 (8,115,495 - 15,491,435) = 11,803,465 = 11,803,465 + 0.5 (15,491,435 - 11,803,465 )
F Febuari ’15
= 13,647,450 F Maret ’15
= 13,647,450 + 0.5 (8,115,495 - 13,647,450 ) = 10,881,472.5 = 10,881,473
dan seterusnya. C. Perhitungan Peramalan Model Pemulusan Exponensial (Exponential Smoothing) dengan α = 0.9 F Januari ’15
= 15,491,435+ 0.9 (8,115,495 - 15,491,435) = 8,853,089
F Febuari ’15
= 8,853,089 + 0.9 (15,491,435 - 8,853,089 ) = 14,827,600.5 = 14,827,601
F Maret ’15
= 14,827,601 + 0.9 (8,115,495 - 14,827,601 ) = 8,786,705.6 = 8,786,706
dan seterusnya.
http://digilib.mercubuana.ac.id/
66
D. Perhitungan Peramalan Produksi Tahun 2016 F Januari ’16
= 15,491,435+ 0.1 (8,115,495 - 15,491,435) = 14,753,841
F Febuari ’16
= 14,753,841 + 0.1 (15,491,435 - 14,753,841 ) = 14,827,600.5 = 14,827,601
F Maret ’16
= 14,827,601+ 0.1 (8,115,495 - 14,827,601) = 14,156,390.4 = 14,156,390
dan seterusnya. E. Perhitungan Peramalan Produksi Tahun 2017 F Januari ’17
= 14,753,841+ 0.1 (14,827,601 - 14,753,841) = 14,761,217 = 14,761,217 + 0.1 (14,753,841 - 14,761,217 )
F Febuari ’17
= 14,760,479.5 = 14,760,480 F Maret ’17
= 14,760,480+ 0.1 (14,827,601 - 14,760,480) = 14,767,192.1 = 14,767,192
dan seterusnya.
http://digilib.mercubuana.ac.id/
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Lampiran 2 : Perhitungan MAD
Peramalan Peramalan Peramalan Produksi Dibulatkan Dibulatkan Dibulatkan Aktual (A) dengan α = dengan α = dengan α = 0.1 0.5 0.9 Januari 15,491,435 14,753,841 11,803,465 8,853,089 Febuari 8,115,495 14,827,601 13,647,450 14,827,601 Maret 14,100,053 14,156,390 10,881,473 8,786,706 April 14,240,846 14,150,756 12,490,763 13,568,718 Mei 9,249,529 14,159,765 13,365,805 14,173,634 Juni 25,558,159 13,668,742 11,307,667 9,741,940 Juli 5,933,333 14,857,684 18,432,913 23,976,537 Agustus 9,691,006 13,965,248 12,183,123 7,737,653 September 10,293,913 13,537,824 10,937,064 9,495,670 Oktober 13,286,418 13,213,433 10,615,489 10,214,089 November 11,162,021 13,220,732 11,950,953 12,979,185 Desember 17,532,579 13,014,861 11,556,487 11,343,738 154,654,788 Periode (2015)
At-Ft (α = At-Ft (α = 0.1) 0.5)
At-Ft (α = |At-Ft| (α |At-Ft| (α |At-Ft| (α 0.9) = 0.1) = 0.5) = 0.9)
737,594 3,687,970 6,638,346 737,594 3,687,970 6,638,346 -6,712,105 -5,531,955 -6,712,105 6,712,105 5,531,955 6,712,105 -56,337 3,218,580 5,313,347 56,337 3,218,580 5,313,347 90,090 1,750,084 672,128 90,090 1,750,084 672,128 -4,910,236 -4,116,275 -4,924,104 4,910,236 4,116,275 4,924,104 11,889,417 14,250,492 15,816,219 11,889,417 14,250,492 15,816,219 -8,924,351 -12,499,580 -18,043,204 8,924,351 12,499,580 18,043,204 -4,274,243 -2,492,117 1,953,352 4,274,243 2,492,117 1,953,352 -3,243,911 -643,151 798,243 3,243,911 643,151 798,243 72,985 2,670,929 3,072,329 72,985 2,670,929 3,072,329 -2,058,710 -788,932 -1,817,164 2,058,710 788,932 1,817,164 4,517,718 5,976,091 6,188,841 4,517,718 5,976,091 6,188,841 ∑ Absolute Devition 47,487,698 57,626,158 71,949,384 MAD (n = 12) 3,957,308 4,802,180 5,995,782
http://digilib.mercubuana.ac.id/
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Lampiran 3 : Perhitungan MSE
Periode (2015)
Produksi Aktual (A)
Januari Febuari Maret April Mei Juni Juli Agustus September Oktober November Desember
15,491,435 8,115,495 14,100,053 14,240,846 9,249,529 25,558,159 5,933,333 9,691,006 10,293,913 13,286,418 11,162,021 17,532,579 154,654,788
Peramalan Peramalan Peramalan Dibulatkan Dibulatkan Dibulatkan At-Ft (α = At-Ft (α = At-Ft (α = dengan α = dengan α = dengan α = 0.1) 0.5) 0.9) 0.1 0.5 0.9 14,753,841 11,803,465 8,853,089 737,594 3,687,970 6,638,346 14,827,601 13,647,450 14,827,601 -6,712,105 -5,531,955 -6,712,105 14,156,390 10,881,473 8,786,706 -56,337 3,218,580 5,313,347 14,150,756 12,490,763 13,568,718 90,090 1,750,084 672,128 14,159,765 13,365,805 14,173,634 -4,910,236 -4,116,275 -4,924,104 13,668,742 11,307,667 9,741,940 11,889,417 14,250,492 15,816,219 14,857,684 18,432,913 23,976,537 -8,924,351 -12,499,580 -18,043,204 13,965,248 12,183,123 7,737,653 -4,274,243 -2,492,117 1,953,352 13,537,824 10,937,064 9,495,670 -3,243,911 -643,151 798,243 13,213,433 10,615,489 10,214,089 72,985 2,670,929 3,072,329 13,220,732 11,950,953 12,979,185 -2,058,710 -788,932 -1,817,164 13,014,861 11,556,487 11,343,738 4,517,718 5,976,091 6,188,841 ∑ Square Error MSE ( n = 12 )
(At-Ft ^2) (α = 0.1)
At-Ft ^2 (α = 0.5)
At-Ft ^2 (α = 0.9)
544,044,908,836 45,052,358,900,709 3,173,875,597 8,116,200,172 24,110,418,946,634 141,358,240,745,967 79,644,034,400,571 18,269,153,041,551 10,522,957,803,167 5,326,825,873 4,238,288,525,570 20,409,778,067,387 344,165,892,242,033 28,680,491,020,169
13,601,122,720,900 30,602,526,122,025 10,359,258,503,832 3,062,792,256,972 16,943,722,757,018 203,076,522,954,589 156,239,502,363,827 6,210,649,353,443 413,643,108,309 7,133,864,068,451 622,414,143,166 35,713,669,135,484 483,979,687,488,014 40,331,640,624,001
44,067,637,615,716 45,052,358,900,709 28,231,658,042,680 451,756,204,318 24,246,803,043,039 250,152,792,033,413 325,557,216,824,379 3,815,584,749,704 637,191,916,219 9,439,206,724,400 3,302,085,292,978 38,301,755,300,022 773,256,046,647,576 64,438,003,887,298
http://digilib.mercubuana.ac.id/
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Lampiran 4 : Perhitungan MAPE
Peramalan Peramalan Peramalan Absolute Absolute Absolute Periode Produksi Dibulatka Dibulatka Dibulatka At-Ft (α = At-Ft (α = At-Ft (α = |At-Ft| (α |At-Ft| (α |At-Ft| (α Percentage Percenta Percenta (2015) Aktual (A) n dengan n dengan n dengan 0.1) 0.5) 0.9) = 0.1) = 0.5) = 0.9) Error (α = ge Error ge Error α = 0.1 α = 0.5 α = 0.9 0.1) (α = 0.5) (α = 0.9) Januari Febuari Maret April Mei Juni Juli Agustus September Oktober November Desember
15,491,435 14,753,841 11,803,465 8,853,089 737,594 3,687,970 6,638,346 737,594 3,687,970 6,638,346 8,115,495 14,827,601 13,647,450 14,827,601 -6,712,105 -5,531,955 -6,712,105 6,712,105 5,531,955 6,712,105 14,100,053 14,156,390 10,881,473 8,786,706 -56,337 3,218,580 5,313,347 56,337 3,218,580 5,313,347 14,240,846 14,150,756 12,490,763 13,568,718 90,090 1,750,084 672,128 90,090 1,750,084 672,128 9,249,529 14,159,765 13,365,805 14,173,634 -4,910,236 -4,116,275 -4,924,104 4,910,236 4,116,275 4,924,104 25,558,159 13,668,742 11,307,667 9,741,940 11,889,417 14,250,492 15,816,219 11,889,417 14,250,492 15,816,219 5,933,333 14,857,684 18,432,913 23,976,537 -8,924,351 -12,499,580 -18,043,204 8,924,351 12,499,580 18,043,204 9,691,006 13,965,248 12,183,123 7,737,653 -4,274,243 -2,492,117 1,953,352 4,274,243 2,492,117 1,953,352 10,293,913 13,537,824 10,937,064 9,495,670 -3,243,911 -643,151 798,243 3,243,911 643,151 798,243 13,286,418 13,213,433 10,615,489 10,214,089 72,985 2,670,929 3,072,329 72,985 2,670,929 3,072,329 11,162,021 13,220,732 11,950,953 12,979,185 -2,058,710 -788,932 -1,817,164 2,058,710 788,932 1,817,164 17,532,579 13,014,861 11,556,487 11,343,738 4,517,718 5,976,091 6,188,841 4,517,718 5,976,091 6,188,841 154,654,788 ∑ Absolute Percentage Error MAPE ( n = 12 )
http://digilib.mercubuana.ac.id/
4.761 23.807 42.852 82.707 68.165 82.707 0.400 22.827 37.683 0.633 12.289 4.720 53.086 44.503 53.236 46.519 55.757 61.883 150.410 210.667 304.099 44.105 25.716 20.156 31.513 6.248 7.755 0.549 20.103 23.124 18.444 7.068 16.280 25.768 34.086 35.299 458.895 531.235 689.794 38.241 44.270 57.483
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Lampiran 5 : Perhitungan Tracking Signal
Peramalan Produksi Dibulatkan Periode Aktual (A) dengan α = 0.1 Januari 15,491,435 14,753,841 Febuari 8,115,495 14,827,601 Maret 14,100,053 14,156,390 April 14,240,846 14,150,756 Mei 9,249,529 14,159,765 Juni 25,558,159 13,668,742 Juli 5,933,333 14,857,684 Agustus 9,691,006 13,965,248 September 10,293,913 13,537,824 Oktober 13,286,418 13,213,433 November 11,162,021 13,220,732 Desember 17,532,579 13,014,861 154,654,788 167,526,877
At-Ft (α = 0.1)
RSFE
737,594 -6,712,105 -56,337 90,090 -4,910,236 11,889,417 -8,924,351 -4,274,243 -3,243,911 72,985 -2,058,710 4,517,718
737,594 -5,974,511 -6,030,849 -5,940,759 -10,850,995 1,038,422 -7,885,928 -12,160,171 -15,404,082 -15,331,097 -17,389,807 -12,872,089
|At-Ft| (α MAD (t) = 0.1) 737,594 6,712,105 56,337 90,090 4,910,236 11,889,417 8,924,350 4,274,242 3,243,911 72,985 2,058,710 4,517,719
61,466 559,342 4,695 7,507 409,186 990,785 743,696 356,187 270,326 6,082 171,559 376,477
http://digilib.mercubuana.ac.id/
MAD 61,466 620,808 625,503 633,011 1,042,197 2,032,982 2,776,677 3,132,864 3,403,190 3,409,272 3,580,832 3,957,308
Tracking Signal Tracking Signal (t) 12.000 -9.624 -9.642 -9.385 -10.412 0.511 -2.840 -3.881 -4.526 -4.497 -4.856 -3.253
0.186 -1.696 -0.014 0.023 -1.241 3.004 -2.255 -1.080 -0.820 0.018 -0.520 1.142 -3.253
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Lampiran 6 : Perhitungan EOQ
Diketahui : Kebutuhan tahun 2017
(D)
= 174,615,035
Biaya pemesanan/setup
(S)
= Rp. 30,000,- perpesanan
Biaya penyimpanan
(H)
= Rp. 26,- pertahun perunit
EOQ : 2𝐷𝑆 𝑄= √ − 𝐻 2 x 174,615,035 x 30,000 √ 𝑄= − 26 2 x 174,615,035 x 30,000 𝑄= √ − 26 𝑄 = 634,789.55 𝑄 = 634,790
Frekuensi Pemesanan : 𝐹=
𝐷 𝑄
𝐹=
174,615,035 634,790
𝐹 = 275.075 𝐹 = 276
http://digilib.mercubuana.ac.id/
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Detail Pemesanan : Bulan Desember Januari Febuari Maret April Mei Juni Juli Agustus September Oktober November Desember
Kebutuhan kotor
14,761,217 14,760,480 14,767,192 14,706,112 14,650,576 14,601,495 14,508,220 14,543,166 14,485,374 14,390,619 14,272,901 14,167,684
Proyeksi persediaan ditangan 15,234,960 473,743 313,433 146,411 40,469 624,853 623,528 80,688 137,692 252,488 462,039 154,518
Kebutuhan Bersih
0 14,286,737 14,453,759 14,559,701 14,610,107 13,976,642 13,884,692 14,462,478 14,347,682 14,138,131 13,810,862 14,013,166
frekuensi pemesanan
Total pemesanan tiap bulan
24 23 23 23 24 23 22 23 23 23 22 23
15,234,960 14,600,170 14,600,170 14,600,170 15,234,960 14,600,170 13,965,380 14,600,170 14,600,170 14,600,170 13,965,380 14,600,170
276
http://digilib.mercubuana.ac.id/
