Judul: Influences of work values on environment at the airport: a case study in five airports in Indonesia
Abstrak: This study was conducted at five airports managed by PT Angkasa Pura I, as follows: Juanda Airport, Surabaya; Hasanuddin Airport, Makassar; Pattimura airport, Ambon; Ngurah Rai Airport, Denpasar; and Sepinggan Airport, Balikpapan. This study aims to identify the value that affect the working conditions of the airport environment, analyzing the influence of each work's value to the quality of the airport environment, identify the needs of stakeholders in improving the performance of airports in the future and formulate implementation strategy needs to be done to improve the environmental performance of the airports. The results of the analysis of stakeholder needs against environmental quality inside and outside the company show that the requirement is: (1) improving the performance of efficient service, clear, precise, and easy airport service users; (2) increase the professionalism of officers who work efficiently, workers spread across several important points, and create familiarity between officers with airport service users, as well as the atmosphere of a friendly waitress from officers; (3) dissemination of clear and strict rules for employees and users services and for law enforcement officers and service users; and (4) improvement of facilities. The results of a prospective analysis found five key factors, namely leadership, cleanliness, care customs, modesty, and tidiness. Based on these five key factors, then the implementation strategy that can be done by PT Angkasa Pura I to improve the quality of the firm is: (1) working with the leadership; (2) always pay attention to neatness, both in appearance and in work; (3) always pay attention to cleanliness; (4) be simple, reasonable, not excessive in employment; and (5) caring for customs or the culture around an enterprise environment.
Keyword: environment, PT Angkasa Pura I, work values, Indonesia

Judul: The Assessment of Trees Environmental Services at Yogyakarta International Airport Kulon Progo
Abstrak: Pembangunan instrastruktur perkotaan memiliki dampak negatif berupa peningkatan konsentrasi polutan di udara. Bandara Internasional Yogyakarta memiliki ruang terbuka hijau yang ditanami pepohonan yang keberadaannya menunjang kegiatan operasional di bandara tersebut. Pohon berkontribusi dalam upaya mereduksi polutan di udara melalui penjerapan dan penyerapan. Peran pohon sebagai cadangan karbon di daratan dapat mengurangi emisi gas rumah kaca di atmosfer. Kontribusi ekologi yang diberikan pohon dapat dinilai dan dibandingkan dengan kondisi di masa mendatang sehingga penelitian ini diperlukan. Tujuan dari penelitian ini adalah menganalisis kemampuan pohon dalam menjerap/menyerap polutan dan menyimpan karbon dan memperkirakan nilai jasa lingkungan yang akan dikontribusikan oleh tata hijau pohon di Bandara Internasional Yogyakarta berdasarkan rencana penanaman yang ada. Metode yang digunakan yaitu pemodelan dengan menggunakan perangkat lunak CITYGreen 5.2 untuk mengetahui manfaat reduksi polutan di udara dan kapasitas cadangan karbon, nilai ekonomi, serta simulasi pertumbuhan pohon dalam 50 tahun mendatang. Penelitian ini menunjukkan hasil bahwa dalam 50 tahun ke depan terdapat peningkatan kemampuan pohon dalam mereduksi polutan (O3, SO2, NO2, PM10, dan CO) dan peningkatan kapasitas penyerapan karbon. Selain itu, diprediksikan bahwa keberadaan pohon hingga 50 tahun ke depan masih mampu untuk mengatasi emisi CO yang berasal dari pembakaran pesawat udara., Urban infrastructure development has a negative impact in the form of increasing concentrations of pollutants in the air. Yogyakarta International Airport has green open spaces planted with trees that support operational activities at the airport. Trees contribute to efforts to reduce pollutants in the air through absorption. The role of trees as carbon stocks on land can reduce greenhouse gas emissions in the atmosphere. The ecological contribution provided by trees can be assessed and compared with future conditions so this research is needed. The purpose of this research is to analyze the ability of trees to absorb pollutants and store carbon and to estimate the value of environmental services that will be contributed by trees at Yogyakarta International Airport based on existing planting plans. The method used is modeling using CITYGreen 5.2 software to determine the benefits of reducing air pollutants and carbon storage capacity, economic value, and modeling tree growth in the next 50 years. This study shows that in the next 50 years there will be an increase in the ability of trees to reduce pollutants (O3, SO2, NO2, PM10, and CO) and increase their carbon absorption capacity. In addition, it is predicted that the existence of trees for the next 50 years will still be able to overcome CO emissions from burning airplanes
Keyword: air pollution, carbon storage, CITYGreen, environmental service, tree

Judul: Cycle Hamilton pada Graf Lengkap, Graf Regular, dan Graf 2-Connected 4-Regular Berorder Kurang dari Sepuluh
Abstrak: Suatu graf disebut graf Hamilton apabila graf tersebut memuat cycle Hamilton, yaitu cycle yang melewati setiap vertex tepat satu kali. Menentukan keberadaan cycle Hamilton pada suatu graf dapat menggunakan syarat cukup yang berupa teorema-teorema yang telah diperkenalkan sejak tahun 1950-an. Beberapa syarat cukup yang dibahas dalam karya ilmiah ini adalah syarat cukup yang berhubungan dengan graf lengkap dan graf regular. Suatu graf lengkap berorder 𝑛������ ≥ 3 dan graf r-regular berorder 𝑛������ ≤ 2𝑟������ + 1 merupakan graf Hamilton, Karena kedua graf tersebut memuat cycle Hamilton. Selanjutnya, syarat cukup tersebut digunakan untuk menentukan keberadaan cycle Hamilton pada graf 2-connected 4- regular berorder kurang dari 10.
Keyword: graf Hamilton, graf regular, graf lengkap, graf 2-connected 4-regular