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OPTIMIZATION OF TRANSPORT SYSTEM IN YOGYAKARTA CITY WITH VEHICLE ROUTING PROBLEM MODEL USING ALGORITHM SEQUENTIAL INSERTION Sari, Rminugroho Ratna; Lestari, Dwi
Jurnal Penelitian Saintek Vol 19, No 1: April 2014
Publisher : Institute of Research and Community Services, Universitas Negeri Yogyakarta

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21831/jps.v19i1.2324

Abstract

The purposes of this study were to build a model for vehicle routing problem (VRP) for waste transportation in Yogyakarta, solve the model obtained using sequential insertion algorithm, then create an Excel Macro programming language to simulate the problem. Waste transportation conditions can be analogous to the VRP by adding intermediate facility at the end of the route, which in this case is the landfill (TPA). To determine waste transportation solved by sequential insertion algorithm. This algorithm is a method to obtain a travel route by updating the node that has not been assigned by inserting between the nodes that have been assigned. Based on 22 TPS simulated with Macro Excel, obtained 4 tours if given planning horizon length is 3 hours, and gained 3 tours if given planning horizon length is 4 hours.  
MODEL PELATIHAN ULANG (RETRAINING) PEKERJA PADA SUATU PERUSAHAAN BERDASARKAN PENILAIAN REKAN KERJA Lestari, Dwi
Jurnal Ilmiah AdMathEdu Vol 1, No 1 (2011): Juni
Publisher : Universitas Ahmad Dahlan

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Abstract

In this paper, its discussed about the model re-training for workers in a company. To improve the quality of workers is usually held training (training) for workers, especially new workers or junior employees. However it is also the possibility of retraining for workers who decline spirit. The condition was one of the bases in formulating a model of retraining for workers in a company. Mathematical models for retraining discussed is a model re-training for workers based on an assessment of his colleagues. This model is shaped system of differential equations. In this model there are two equilibrium points namely the trivial equilibrium point and non-trivial equilibrium point. Local stability of the trivial equilibrium point of time fulfilled the conditions of the reproductive number is essentially less than one. This means that for a long time a good worker does not need to be a master so that workers do not re-training. Numerical simulation is given by taking the value of certain parameters that describe the changes in population size of each class of a time.
ANALISIS KONDISI HIDROLOGI KAITANNYA DENGAN KUALITAS AIR DAN SOSIAL DI SUBDAS CITARUM SANGHYANG TIKORO Lestari, Dwi; Haryanti, Titik Umaiyah; Abdillah, Moch. Fery; Khomariyah, Nur Lailatul; Hisyam, Giffari Ibnu; Anggara, Bayu Putra; Utami, Arum Cahyaning; Khoiroh, Aisyah Widatul; Nurdin, Elan Artono
MAJALAH PEMBELAJARAN GEOGRAFI Vol 2 No 3 (2019): MAJALAH PEMBELAJARAN GEOGRAFI
Publisher : DEPARTMENT OF GEOGRAPHY EDUCATION, UNIVERSITY OF JEMBER

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Abstract

Tujuan dari penelitian ini ialah untuk menganalisis kondisi hidrologi kaitannya dengan kualitas air untuk dimanfaatkan oleh masyarakat di daerah Sanghyang Poek/Tikoro. Metode penelitian yang digunakan berupa penelitian deskriptif dengan observasi, dokumentasi, dan pengukuran data lapangan untuk memperoleh data. Pengukuran dilakukan dengan TDS dan pH meter serta GPS. Teknik analisis berupa analisis deskriptif. Penelitian yang dilakukan menunjukkan hasil denan nilai TDS sebesar 193 ppm, pH sebesar 8,8, suhu 30,5 0C dengan ketinggian 311 mdpl. Hasil pengukuran ini menunjukkan bahwa air masih bisa digunakan untuk kebutuhan masyarakat. Daerah ini merupakan daerah pegunungan yang tidak mengalami proses erupsi dengan topografi lahan sedikit terjal karena masih satu area dengan pegunungan Karst Rajamandala dan bekas sungai bawah tanah ditandai adanya stalagtit dan stalagmit.Sungai berada di tempat dengan karakteristik seperti ini termasuk kedalam sungai stadia dewasa. Stadia dewasa yang juga bagian tengah dari DAS digunakan untuk kawasan penyangga.  Kata kunci : Hidrologi, DAS Citarum, Kualitas Air
DESKRIPSI KOMUNIKASI MATEMATIS TERTULIS PADA PEMBELAJARAN MATEMATIKA SISWA KELAS XI SMA NEGERI DI PURWOREJO Lestari, Dwi
EKUIVALEN - Pendidikan Matematika Vol 20, No 3 (2016): EKUIVALEN
Publisher : Universitas Muhammadiyah Purworejo

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Abstract

Penelitian ini bertujuan untuk mendeskripsikan kemudian mengetahui kemampuan komunikasi matematis secara tertulis siswa kelas XI IPA SMA dalam pembelajaran matematika.Penelitian ini adalah penelitian kualitatif studi kasus. Subjek dalam penelitian ini adalah siswa kelas XI IPA SMA Negeri 7 Purworejo pada tahun ajaran 2015/2016. Teknik pemilihan subjek sumber data yang digunakan adalah teknik purposive sampling dan snowball sampling. Teknik pengumpulan data menggunakan observasi, tes tertulis dan dokumentasi. Teknik pemeriksaan keabsahan data menggunakan triangulasi teknik dan triangulasi teori.Berdasarkan hasil analisis data dapat disimpulkan bahwa komunikasi matematis siswa pada pembelajaran matematika secara tertulis tergolong baik karena telah memenuhi kriteria indikator komunikasi matematis tertulis. Hal ini dapat dilihat ketika siswa dapat menghubungkan benda nyata, gambar, dan diagram ke dalam ide matematika; menjelaskan ide, situasi, dan relasi matematika secara tertulis dengan benda nyata, gambar, grafik, dan aljabar; menyatakan peristiwa sehari-hari dalam bahasa atau simbol matematika serta dapat membuat konjektur, menyusun argumen, merumuskan definisi, dan generalisasi tentang permasalahan matematika.   Kata kunci: Komunikasi matematis tertulis
UJI BRINE SHRIMP LETHALITY TEST (BSLT) UMBI BAWANG TIWAI (ELEUTHERINE BULBOSA (MILL.) URB) DAN UJI TOKSISITAS AKUT FRAKSI AKTIF Lestari, Dwi; Kartika, Rudi; Marliana, Eva
Jurnal Riset Kefarmasian Indonesia Vol 1 No 1 (2019): Jurnal Riset Kefarmasian Indonesia
Publisher : APDFI (Asosiasi Pendidikan Diploma Farmasi Indonesia)

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (310.051 KB) | DOI: 10.33759/jrki.v1i1.43

Abstract

Eleutherine bulbosa (Mill.) Urb come from the Iridaceae family, this species contains secondary metabolites in the form of flavonoids and quinones. This research method includes Brine Shrimp Lethality Test (BSLT) toxicity using Artemia salina Leach larvae to determine the LC50 value. This study used experimental methods pharmacologically using a completely randomized design in the same direction pattern in the selection of test animals, 25 animals used were white mice divided into 5 groups with 5 mice per group, with 4 hours observed to find out toxic symptoms and continued observation every 24 hours to see death. Testing of BSLT results showed that ethanol extract had LC50 toxicity = 66.68 ppm (very toxic category), n-hexane fraction had LC50 toxicity = 47.64 ppm (very toxic category), chloroform fraction had LC50 toxicity = 295.1 ppm ( toxic category), and the water fraction has a toxicity of LC50 = 194.54 ppm (very toxic category). The chloroform fraction is an active fraction. Acute toxicity test LD50 value according to the calculation method of Miller Tainter Probit (187,499 mg/KgBB), the method of calculation of Thompson Weil (182,810 mg/KgBB), how to calculate Indonesian Pharmacopoeia (187,068 mg/KgBB). Based on the three calculations, the LD50 value is in the medium category (50-500 mg/kgBB).
The password agreement method based on matrix operation over Min-Plus algebra for safety of secret information sending Musthofa, Musthofa; Lestari, Dwi
Jurnal Sains Dasar Vol 3, No 1 (2014): Jurnal Sain Dasar
Publisher : Universitas Negeri Yogyakarta

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Abstract

Key agreement protocol is a method in cryptography. Key agreement protocol is used to overcome the problem of sending secret information over communication lines. A secret key, called password, is needed to secure t he information. Both parties who exchange confidential information must agree on the same key. In this method, both parties exchange mutual general parameters that everyone can see, however from the general parameters the same passwords can be formed and not publicly known. One method that has been used is applying a series of matrix multiplication operation defined over a finite field. In this study, we constructed an algorithm in the form of a key agreement protocol that can be used in the password agreement method which the level of security based on algebraic problem of matrix operation over Z- min plus algebra. Min Plus algebra over Z, that is Z È { + ¥ } with Z is the set of all integers equipped with the minimum and addition operation,  is called idempotent semiring. The results showed that the application of matrix operation over min plus algebra can be used as key agreement protocol in securing secret information.   Key words: secret information, password, Min-Plus algebra
PENGARUH KONSEP DIRI, IQ, IKLIM SEKOLAH, PERSEPSI SISWA TENTANG KOMPETENSI GURU Lestari, Dwi; Purnomo, Edy; Nurdin, Nurdin
JEE (Jurnal Edukasi Ekobis) Vol 2, No 5 (2014): JEE (jurnal Edukasi Ekobis)
Publisher : FKIP Unila

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Abstract

The goal of this research is to know the effect of self-concept, Intelligence Quotient (IQ), school climate, and student perceptions of teacher competence on economic learning outcomes. The method used is descriptive method of verification. Data collecting technique that is using by questionnaires and documentation. Testing hypotheses is using regression analysis techniques. Based on the results obtained findings (1) There is the influence of self-concept on learning outcomes of the economy; (2) There is an effect on learning outcomes IQ economy; (3) There is an influence of school climate on learning outcomes of the economy; (4) There is an influence of students perceptions of teacher competence on economic learning outcomes; and (5) There is an influence of self-concept, IQ, school climate, and student perceptions of teacher competence on economic learning outcomes.  Penelitian ini bertujuan untuk mengetahui pengaruh konsep diri, Intelligence Quotient (IQ), iklim sekolah, dan persepsi siswa tentang kompetensi guru terhadap hasil belajar ekonomi. Metode yang digunakan adalah metode deskriptif verifikatif. Teknik pengambilan data yaitu dengan angket dan dokumentasi. Pengujian hipotesis menggunakan teknik analisis regresi. Berdasarkan hasil penelitian diperoleh temuan (1) Ada pengaruh konsep diri terhadap hasil belajar ekonomi; (2) Ada pengaruh IQ terhadap hasil belajar ekonomi; (3) Ada pengaruh iklim sekolah terhadap hasil belajar ekonomi; (4) Ada pengaruh persepsi siswa tentang kompetensi guru terhadap hasil belajar ekonomi; dan (5) Ada pengaruh konsep diri, IQ, iklim sekolah, dan persepsi siswa tentang kompetensi guru terhadap hasil belajar ekonomi. Kata kunci: hasil belajar, iklim sekolah, IQ, konsep diri, persepsi siswa tentang kompetensi guru.
Rancang Bangun Mesin Pemarut Dan Pemeras Santan Kelapa Portable Model Kontinyu Lestari, Dwi; Susilo, Bambang; Yulianingsih, Rini
Jurnal Keteknikan Pertanian Tropis dan Biosistem Vol 2, No 2 (2014)
Publisher : Universitas Brawijaya

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Abstract

Penelitian ini bertujuan untuk membuat rancang bangun pemarut dan pemeras santan kelapa portable model continue bertenaga gerak motor listrik, mengetahui sistem kerja dengan uji coba dan identifikasi tingkat kegagalan perancangan serta menghitung tingkat efisiensi dengan perbandingan metode manual. Metode Penelitian yang digunakan dalam penelitian rancang bangun mesin pemarut dan pemeras santan kelapa portable model continue ini adalah metode empirik, yaitu pengambilan data dari sumber studi pustaka lalu mengaplikasikanya dalam satu permodelan dimensi dengan perencanaan dan perhitungan yang diwujudkan dalam satu bentuk nyata berupa mesin pemarut dan pemeras santan kelapa portable model continue tersebut. Untuk mengetahui besar kapasitas mesin dibutuhkan pengulangan beberapa kali dengan pengambilan waktu 5 menit, 10 menit, 15 menit, 20 menit, 25 menit, 30 menit sampai 60 menit. Hasil penelitian dibedakan menjadi dua sesuai parameter penelitian, yaitu santan dan ampas. Rancangan mengalami beberapa kali perubahan design dan ukuran komponenya, hal ini untuk mendapatkan hasil yang mendekati sempurna. Hasil pengujian tertinggi terjadi pada waktu 10 menit yaitu, santan 110 gr, dan ampas 220 gr. sedangkan pada pengujian mulai 25 menit hingga 60 menit tidak menghasilkan santan. Hal ini dikarenakan mesin mengalami eror.
PENGARUH PENAMBAHAN SARGASSUM SP. DAN INOSITOL DALAM PAKAN TERHADAP PERTUMBUHAN DAN DAYA TAHAN JUVENIL IKAN GURAMI (OSPHRONEMUS GOURAMY LAC.) Lestari, Dwi; Widiastuti, E. L.; Nurcahyani, N.; Susanto, G. N.
Jurnal Natur Indonesia Vol 16, No 2 (2016)
Publisher : Lembaga Penelitian dan Pengabdian kepada Masyarakat Universitas Riau

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (96.86 KB) | DOI: 10.31258/jnat.16.2.72-78

Abstract

Gourami (Osphronemus gouramy Lac.) as one of the freshwater fishes, are easily to be cultured but slow in growth rate. One of the ways to enhance their growth rate is by feeding them with high nutritious food. Sargassum sp. and inositol are known compound able to stimulate the growth of some fishes. The study was conducted to determine the effect of Sargassum sp and inositol on commercial feed to the growth rate and survival of juvenile gouramy. The study was conducted from January to April 2015 in Aquatic Laboratory of Biology Department - University of Lampung. Completely randomized designed was used with 4 treatment groups and 5 replications. Anova and Tukey at 5% levels were applied to this study. The result indicated that addition of inositol and Sargassum sp on commercial food significantly affected the gourami growth parameters such as the body weight, body length, body width as well as juvenile gouramy spesific growth rate and their survival rate.
MODEL PERTUMBUHAN POPULASI BERDASARKAN KELOMPOK UMUR Lestari, Dwi
Pythagoras: Jurnal Pendidikan Matematika Vol 5, No 1: Juni 2009
Publisher : Department of Mathematics Education, Faculty of Mathematics and Natural Sciences, UNY

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21831/pg.v5i1.560

Abstract

Penelitian matematika dalam bidang demografi dan ekologi sangatlah penting. Salah satu penelitian di bidang tersebut adalah tentang pertumbuhan populasi. Paper ini akan membahas tentang model pertumbuhan populasi berdasarkan kelompok umur. Model populasi berdasar kelompok umur merupakan model untuk memprediksi jumlah populasi di waktu yang akan datang berdasarkan kelompok umur. Model ini berbentuk kontinu atas waktu dan diskret atas kelompok umur. Model ini dikembangkan dari model pertumbuhan populasi berdasarkan kelompok umur dengan ukuran waktu diskret dan ukuran umur diskret. Dalam hal ini akan dibahas model kontinu atas waktu dan diskret atas umur sehingga diperoleh model berupa sistem persamaan diferensial serta model dapat dituliskan dalam bentuk matriks. Perubahan populasi yang meliputi increasing, decreasing, dan asyimptoticaly stationary dapat dilihat dari nilai eigen dari matriks yang terbentuk. Selain itu dapat dilihat stable age structure nya. Kata kunci : model populasi, kelompok umur (age-structured), stable age structure.
Co-Authors ., Murwati Abdillah, Moch. Fery Adi Widarma, Adi Agung Yulianto Albertus Djoko Lesmono, Albertus Djoko Anggara, Bayu Putra Anik Nuryati, Anik Arta Farmawati Asih Rohmani, Asih Atmini Dhoruri Bambang Susilo Burhan Barid, Burhan Dian Kresnadipayana, Dian Donny Fransiskus Manalu, Donny Fransiskus E. L. Widiastuti, E. L. Edy Purnomo Eka Siswanto Syamsul, Eka Siswanto Elin Yulinah Sukandar Eminugroho Ratna Sari Endah Retnowati, Endah Eva Marliana, Eva Fitriana Yuli S, Fitriana Gusmelia Testiana, Gusmelia Haryanti, Titik Umaiyah Heliani, Leni Sophia Hisyam, Giffari Ibnu Hisyam, Giffari Ibnu I Wayan Suardana Ikhsan, Fahrudi Ahwan Isnaini, Een Lujainatul Isnaini, Fatimah Noor Istiqomah, Nusaibah Al Jumnahdi, Muhammad Karina, Yunia Dwi Kartikaningdyah, Ely Kartikasari, Ratih Indah Ketut Sukiyono Khoiroh, Aisyah Widatul Khomariyah, Nur Lailatul Komang Januartha Putra Pinatih Krahayon, Metri Utami Kurnianto, Fahmi Arif Lily Arsanti Lestari Marianne Marianne Marlina, Eva Maryani Maryani Mila Karmila Mohammad Muktiali Muniroh Munawar Musthofa Musthofa N. Nurcahyani, N. Neng Fisheri Kurniati Novidariyanti, Evira Nugroho, Krishna Fitranto Nurdin Nurdin Nurdin, Elan Artono Nurrohmat Widjajanti, Nurrohmat Parseno Parseno Pratama, Cecep Pratiwi, Inti Nur Tirta Putri Kusumawati Priyono Redy Badrudin, Redy Rini Yulianingsih Riza Agustiani, Riza Rminugroho Ratna Sari Rosnani Nasution Rozaq, Dimas Abdur Rudi Kartika, Rudi Safitri, Hana Ika Sahid Sahid Sanyoto, Nugroho Tri Sanyoto, Nugroho Tri Sari, Rizki Iman Setyaningtyas, Eunice Widyanti Siallagan, Dorsinta Siti Heldyana, Siti Siti Nuryani, Siti Sri Haryani Sudarmin Sudarmin Sugiyono Sugiyono Surakhman, Surakhman Surakhman, Surakhman Susanto, G. N. Triyanto, Lilik Turtiantoro . Ulinnuha, Hilmiyati Utami, Arum Cahyaning Wahida, Iqni’a Fajril Wiryatun Lestariana, Wiryatun Yulaikhah Yulaikhah