In Indonesia, there are many farmers as a livelihood because of fertile soil for agriculture and the demand for food. Production planning is the important part of managing cost spent by the company. In production planning, there are many constraints which have to be satisfied such as the number of productions, the number of workers, and the number of inventory. In previous research, constrained optimizations have been solved by exact method or heuristic method. In this research, production planning optimization will be solved by Firefly Algorithm (FA). FA works as a behavior of Firefly. One of firefly behavior used is less bright firefly will move toward brighter firefly. The simulation results show that FA method can find an approaching optimal solution of production planning like production cost, worker cost, and inventory holding cost satisfying the constraints of the number of productions, workers, and inventory.

Abstract. Since come the rice thresher (combi) machine effective than the manual process, the rice milling industries such us UD Lancar,  only receiving the grain which produced from it so the supplay of rice is decreasing so resulting in the risk of loss for themselves. The forecasting activity in here used for to assist UD Lancar  in estimating the demand for rice in the next period, so can anticipate looking for other grain supplier for to fulfill the demand of market. The data will be analyzed using the Double Exponential Smoothing Holt and ARIMA method. The result of the data processing is show the Double exponential smoothing holt method has MSE error value of 413.445.841,75,while in the ARIMA (2,1,1) method has MSE value was 64.826.353,94404. The Arima (2,1,1) method is better than the double exponential smoothing Holt method because it has a smaller MSE value, so it can be used in the forecasting.   Keywords: Forecasting, Double Exponential Smoothing Holt, ARIMA.   Abstrak. Sejak adanya mesin perontok padi (combi) yang memiliki tingkat efektifitas lebih baik dibandingkan proses manual,  para pemilik industri penggilingan padi seperti UD Lancar kini hanya menerima gabah hasil proses mesin combi yang mengakibatkan persediaan beras mengalami penurunan sehingga dapat mengakibatkan permintaan konsumen tidak terpenuhi dan berujung pada resiko kerugian. Kegiatan peramalan ini bertujuan untuk memperkirakan permintaan beras UD Lancar pada periode selanjutnya, sehingga UD Lancar dapat mengantisipasi dengan cara mencari pemasok gabah lain untuk memenuhi permintaan pasar. Analisis data menggunakan metode Double Exponential Smoothing Holt dan ARIMA. Berdasarkan hasil analisis, pada metode Double Exponential Smoothing Holt memiliki nilai kesalahan MSE sebesar 413.445.841,75, sedangkan metode ARIMA (2,1,1) memiliki nilai kesalahan MSE sebesar 64.826.353,94404. Metode ARIMA (2,1,1) memiliki nilai kesalahan MSE lebih kecil dibandingkan metode Double Exponential Smoothing Holt, sehingga dapat digunakan dalam proses peramalan.   Kata Kunci: Peramalan, Double Exponential Smoothing Holt, ARIMA.

Kesehatan lingkungan menurut WHO (World Health Organization) adalah suatu keseimbangan ekologi yang harus ada antara manusia dan lingkungan agar dapat menjamin keadaan sehat dari manusia. Dengan demikian, lingkungan yang bersih sangat berpengaruh pada kesehatan masyarakat baik jasmani maupun rohani. Indikator lingkungan bersih dapat dilihat dari persentase keluarga yang mempunyai akses air bersih baik dari PDAM (Perusahaan Daerah Air Minum), sumur atau dari sumber lainnya. Desa Keting merupakan salah satu desa di Kecamatan Sekaran Kabupaten Lamongan. Desa Keting terdiri dari dua dusun, yaitu Dusun Keting dan Dusun Kedalon yang keduanya dilaui oleh sungai yang cukup besar yaitu bengawan solo. Berdasarkan indikator lingkungan bersih diatas, Desa keting memenuhi beberapa poin diantaranya sumber air bersih yang memadai ditandai dengan banyak masyarakat yang mempunyai sumur pribadi. Kegiatan pengabdian ini terfokus pada aksi bersih lingkungan masyarakat Desa Keting yang bertujuan untuk menciptakan lingkungan Desa Keting yang bersih dan sehat. Kegiatan diawali dengan sosialisasi pengenai bahaya buang sampah dan limbah di sungai, aksi bersih sungai, aksi bersih jalan desa, aksi bersih masjid, aksi bersih makam, dan pengadaan tong sampah di pinggir jalan serta tempat umum.

Peat soil is an organic soil with very low carrying capacity and high compressibility. The condition is less profitable for civil engineers in building a civil foundation foundation. One method of peat soil improvement can be done with astabilization method that more environment-friendly and cheaper than other methods. Laboratory based peat stabilization studies to increase carrying capacity, reduce compression and improve peat soil physical properties have been conducted in Indonesia. The results of laboratory studies shown in the graph are still limited by time and content of the mixture. Therefore, further research is needed on the mathematical model toward the physical properties of peat soil stabilization. In this research will be formulated mathematical model of water content on the physical properties of peat soil stabilization. The model is derived from the fluid equation through porous media based on the principle of continum and controlvolume. The model is then resolved numerically by different method until MacCormack scheme with two steps are predictor step using forward difference and correctorstep using backward difference. The MacCormack scheme has the advantage of solving fluid flow equations and continuity. The model is then simulated and validated by comparing the simulation results with the real system. From the simulation results obtained the water content gradually decreased, the decrease is almost close to zero. In addition, it can be seen the difference in decrease in moisture content at each test point although in small quantities.

Keting village, Kedalon hamlet is a village that still has a lot of rice fields and livestock. However, many people are still not using animal manure (livestock) to be used as fertilizer in the rice fields. In this case, the community still uses chemical fertilizers and allows the manure from the farm to be wasted for nothing. The purpose of this community service is to manage goat manure into solid organic fertilizer or manure to replace chemical fertilizers in Kedalon Hamlet. The method used in this activity is socialization and the practice of making fertilizer. The results of the service are products in the form of solid organic fertilizers derived from goat manure, so that comunity can use these fertilizers to replace chemical fertilizers.