In survival analysis to determine the relationship between variables is used a regression model, one of which uses the semiparametric regression model. The semiparametric regression model is a model that does not require assumptions or information on survival data distribution. That way, this model is more flexible in its use. In this study, the semiparametric regression model used the Cox Proportional Hazard (Cox PH) regression model. Estimation of Cox PH regression parameters can be done without determining the function baseline hazard. The purpose of this study is to determine the factors that influence the duration of student studies. If there are many students whose studies have not been on time, it shows that there is a lack of professionalism in the academic field of the educator. Thus, the community will assess the low quality of the university, resulting in a decrease in the number of students who want to study at the university. The samples in this study were students of class 2014 Universitas Islam Darul Ulum Lamongan. The variables have used the length of study for students, gender, GPA, school origin, organization, and work. Based on the results of the assumption Proportional Hazard (PH) conducted, all independent variables have fulfilled these assumptions, so that these variables can be used in Cox PH regression. After parameter estimation by Cox PH regression, the GPA and organizational factors significantly influence the duration of student study. Students with high GPA and participating in organizations more quickly complete their studies.

Nowadays, the demands of flight service are very high so that flight industry should minimize operational cost such as crew cost. Crew cost depends on pairings from flight schedule. Optimization model of this problem is selecting optimal pairings covering all flight numbers in the goal programming model as multiobjective programming. In this research, goal programming on optimal pairings selection will be applied by heuristic method like Bat Algorithm (BA). BA is optimization method inspired from behavior of bats like they use sonar called echolocation to detect prey, avoid obstacles, and locate their roosting crevices in the dark. BA can be applied on constrained optimization. Simulations are applied by generating the set of pairings and selection using BA. The advantages of BA are there are a local solution around the selected best solution based on pulse rates and loudness. In the optimal pairings selection model, there are three objectives which will be minimized based on order of importance. The simulation results show that Bat Algorithm can be used in goal programming model and it can select optimal pairings in approaching with the number of pairing consisting of two flight numbers is 4 pairings, the number of pairing consisting of three flight numbers is 0 pairing, the number of pairing consisting of four flight numbers is 49 pairings, the number of pairing consisting of five flight numbers is 7 pairings and the number of pairing consisting of six flight numbers is 8 pairings.

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.

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.