Judul: Tata Niaga dan Pendugaan Volume Perdagangan Ilegal Trenggiling (Manis javanica Desmarest 1822)
Abstrak: Perburuan dan perdagangan ilegal trenggiling menyebabkan penurunan populasi trenggiling di alam dan menyebabkan negara mengalami kerugian secara ekologi dan ekonomi. Penelitian ini bertujuan untuk mengidentifikasi alur tata niaga, karakteristik pelaku, serta menduga volume dan nilai perdagangan ilegal trenggiling. Metode yang digunakan yaitu wawancara dengan staf BKSDA Jawa tengah dan BKSDA Yogyakarta, dan studi literatur. Data yang digunakan yaitu data operasi perdagangan satwa liar ilegal tahun 2015-2020 dari Ditjen GAKKUM-KLHK, GAKKUM Sumatera, BKSDA Yogyakarta, BKSDA Jawa Tengah, dan penelusuran dokumen melalui SIPP MA. Data dianalisis menggunakan deskriptif kualitatif dan kuantitatif. Hasil penelitian mengidentifikasi 5 jenis alur tata niaga ilegal yang didominasi oleh jenis alur restricted access 49% dan multiple barriers to market 25%. Alur tata niaga melibatkan warga lokal, bersifat tertutup dan kompleks. Pelaku merupakan usia produktif dan didominasi oleh laki-laki. Pemburu cenderung memiliki mata pencaharian sebagai buruh dan perantara sebagai pedagang. Bagian yang dijual dari trenggiling yaitu trenggiling utuh, sisik dan dagingnya dengan volume perdagangan ilegal trenggiling periode 2015-2020 sejumlah 4100 ekor dan nilai perdagangannya sebesar Rp6.032.202.989,00., Poaching and illegal trade in sunda pangolins cause a decline in population in the wild and detrimental to the country ecologically and economically. This study aims to identify the flow of commerce system, perpetrator’s characteristics, and to estimate the volume and value of illegal trade pangolins. The method used was an interview with the staff of BKSDA Central Java, BKSDA Yogyakarta, and literature studies. Used are data on illegal wildlife trade operations in 2015-2020 from the Directorate General of GAKKUM-KLHK, GAKKUM Sumatra, BKSDA Yogyakarta, BKSDA Central Java, document search through SIPP MA. Data analysis using qualitative and quantitative descriptive. There were 5 types of illegal pangolin commerce systems which were dominated by 49% restricted access and 25% multiple barriers to market. The flow of commerce system involves residents, is closed and complex. Perpetrators are productive age, dominated by men. Hunters tend to have a livelihood as laborers and intermediaries as traders. The parts that are sold from pangolins are whole pangolins, scales, and meat. The illegal trade volume of pangolins for the 2015-2020 period was 4100 animals and illegal trade value was IDR 6.032.202.989.
Keyword: tata niaga, trenggiling, volume perdagangan, commerce system, sunda pangolin, trading volume

Judul: Trade System and Estimated Illegal Trading Volume of Orangutan (Pongo pygmaeus)
Abstrak: Perdagangan ilegal satwa liar membutuhkan perhatian khusus karena berdampak pada penurunan populasi, kehilangan sumber daya, dan kerugian negara. Orangutan merupakan satwa dilindungi yang diperdagangkan secara ilegal di Indonesia. Penelitian ini bertujuan untuk mengidentifikasi alur tata niaga, karakteristik pelaku, serta menduga volume dan nilai perdagangan ilegal orangutan. Metode yang digunakan yaitu wawancara kepada kepala resort Bangka Belitung BKSDA Sumatera Selatan, manajer PPS Alobi, Ditjen Gakkum LHK, dan studi literatur. Data yang digunakan yaitu data perdagangan ilegal orangutan pada kurun waktu 2015-2020 yang diperoleh dari Ditjen Gakkum LHK dan penelusuran data kasus Mahkamah Agung. Data dianalisis menggunakan deskriptif kualitatif dan kuantitatif. Hasil penelitian menemukan tiga alur tata niaga yang didominasi oleh redundant channels sebesar 75%. Pelaku terdiri dari pemburu, perantara, dan konsumen yang didominasi oleh laki-laki dengan usia produktif kerja. Pekerjaan pemburu dan perantara didominasi oleh petani dan pedagang dengan didominasi motivasi ekonomi. Volume perdagangan ilegal orangutan periode 2015-2020 sebanyak 15 individu dengan nilai perdagangan mencapai Rp435.000.000,00., Illegal wildlife trade requires special attention because it has an impact on population decline, loss of resources, and detrimental to the country. Orangutans are protected animals that are illegally traded in Indonesia. This study aims to identify the flow of the trade system, perpetrator’s characteristics, and to estimate the volume and value of the illegal trade in orangutans. The method used was an interviews with the head of resort Bangka Belitung BKSDA Sumatra Selatan, PPS Alobi manager, Ditjen Gakkum LHK, and literature studies. Data used is data on the illegal trade in orangutans in the 2015-2020 period that obtained from Ditjen Gakkum LHK and the investigation of Mahkamah Agung case data. Data were analyzed using qualitative and quantitative descriptive. The results of the study found that are three channels of commerce which were dominated by redundant channels about (75%). The perpetrators consist of hunters, intermediaries, and consumers who are dominated by men of working productive age. The jobs of hunters and intermediares are dominated by farmers and traders with a predominantly economic motivation. Volume of illegal trade in orangutans for the 2015-2020 period was 15 individuals with a trade value was IDR435,000,000,00.
Keyword: illegal, orangutan, trade, Illegal, orangutan, trade

Judul: Hamiltonian formulation for linear waves motion in two layers fluid
Abstrak: The surface wave could be considered as a wave that separates two fluids, namely water and air. Based on this assumption, it is introduced the interfacial wave, a wave between two layers of fluid with different density. The formulation of interfacial waves motion begins with deriving the base equation of irrotational ideal fluid. Furthermore, according to irrotational fluid assumption, the base equation can be stated in velocity potential. In this derivation, the fluids domain is assumed to be restricted by rigid lid boundary conditions, both at the upper and lower limit. Therefore, the interfacial waves motion can be explained in a hamiltonian formulation. In the hamiltonian formulation, total energy is defined as the sum of kinetic and potential energy. The hamiltonian system is obtained from reduction of kinetic energy by using the Dirichlet Neumann Operator. The resulted kinetic energy equation is nonlinear. Therefore, this form is linearized by first part of the Taylor expansion. This linearization gives a dispersion relation of linear wave. Based on this dispersion relation, the phase speed of the linear wave depends on the density ratio of the two layers fluid.
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