Judul: Refrigerated Portable Refrigerated Fish Storage for Small Scale Fisheries
Abstrak: Metode penyimpanan ikan dengan suhu rendah merupakan salah satu proses penanganan yang sangat dibutuhkan untuk menjaga kualitas ikan pasca penangkapan. Penggunaan es sebagai media penyimpanan juga ternyata hanya dapat bertahan dalam waktu yang singkat serta seringkali memberikan kerusakan fisik pada ikan. Hal tersebut memunculkan ide untuk dapat membuat alternatif penyimpanan ikan berpendingin di atas kapal sebagai solusi dari masalah tersebut. Tujuan dari penelitian ini adalah: (1) membuat rancangan portable mini fish box; (2) mengetahui kebutuhan daya dan performa portable mini fish box; (3) mengetahui efisiensi biaya dalam pengoperasian portable mini fish box. Hasil penelitian ini menunjukkan bahwa Mini Fish Box dapat dibangun dengan menggunakan sistem refrigerasi dengan dimensi 65x66x50 cm. Besar daya yang dibutuhkan portable mini fish box secara berturut-turut untuk kondisi tanpa beban dan beban 4 kg adalah 374,94 watt dan 651,93 watt dengan waktu yang dibutuhkan untuk mencapai suhu 5 oC adalah 34 menit pada kondisi berawan tanpa beban dengan suhu lingkugan berkisar 23-30 oC dan waktu terlama adalah 76 menit dengan kondisi terik berbeban pendinginan 4 kg dengan suhu lingkungan berada pada antara 30–36 oC. Portable mini fish box juga secara efektif dapat menghemat 90% dari biaya pendingin konvensional dengan biaya perkg ikan yang dikeluarkan hanya sebesar Rp127/kg hasil tangkapan., The method of storing fish at low temperatures is one of the handling processes that is needed to maintain the quality of fish after capture process. The use of ice as a storage medium also turns out only works in short time and often causes physical damage to fish. This gave rise to the idea of creating an alternative to refrigerated fish storage on board as a solution to this problem. The objectives of this research are: (1) to design a portable refrigerated fish storage; (2) determine the power and performance requirements of a refrigerated portable storage; (3) find out the cost efficiency in operating a refrigerated portable storage compare to traditional fish storage. The results of this study indicate that a portable storage can be built using a refrigeration system with dimensions of 65x66x50cm. The power requirements required for a refrigerated portable storage respectively for no-load and 4 kg load conditions are 374.94 watt and 651.93 watt with the time needed to reach 5 oC temperature is 34 minutes in cloudy conditions without load and the longest time is 76 minutes in hot conditions. 4 kg cooling load. The refrigerated portable storage can also effectively save 90% of the cost of conventional coolers with a per kg fish cost of only Rp127 per kg of catch.
Keyword: efisiensi biaya, kesegaran ikan, portable mini fish box, cost efficiency, fish quality

Judul: Desain alat transportasi ikan segar berpendingin untuk pedagang ikan keliling
Abstrak: Deterioration of fish quality after catching is still quite high at about 27 percent. It caused by mishandling of fish during transportation from the fish auction to consumers. The mishandling of fish caused by transportation equipment that used by traders use styrofoam box and plastic buckets. The equipment is not effective to implement cold chain system. The transportation equipment is difficult to apply on a motorcycle so upset the balance of driving. This study aims to maintain the quality of fresh fish and facilitate the transport of fish for fish traders by motorcycle. To achieve these objectives is done by designing the fish refrigerated container Design steps of fish refrigerated container in this study includes the identification of user needs, determination of design criteria, conceptual design, design analysis, drafting, manufacture process and performance test. Identification of user needs carried out by determining the physical characteristics of fish and motorcycles, determine the trading activities, transportation equipment capacity and the duration of the transport process. Specified design criteria of refrigerated container are : (1) fish refrigerated container can maintain the fish temperature below 10 °C, (2) fish refrigerated container using thermoelectric cooler, (3) fish refrigerated container can maintain the fish quality, (4) fish refrigerated container compatible with a motorcycle, (5) fish refrigerated container could assist the fish trading. Functional design of refrigerated container are to maintain the fish temperature below 10 °C, to place the equipment of trading activities and set the refrigerated container on a motorcycle. The container was designed using alumuninum plat of 0.5 mm thick with 33 mm thick of polyurethane insulation. A thermoelectric cooler equipped with a heatsink and heat pipes were used for maintaining a lower temperature in the container and the motorcycle accu were used for power supply. As for fish traders, a pair of container was set on a motorcycle using a suspending frame. Design analysis showed that cooling load of refrigerated container was 11.21 Watts/container. Its derived from transmission load through walls was 7.24 Watt and air infiltration when opening and closing cap of refrigerated container was 3.97 Watts. Stress analysis of suspending frame showed that the stress distribution on suspending frame maximum was 8 x 106 N/m2 and yield strength values was 5.5 x 107 N/m2, while the maximum displacement occurring was 0.072 mm. Several performance tests were conducted using load and without load. Performance tests using load were carried out in actual tradings. Performance tests without load was conducted to determine the temperature of the fish storage and determine the COP of refrigerated container. Performance tests were carried by trader to determine the fish temperature, fish quality after transport activity and determine acceptance traders. In this study, also conducted economic studies for fish transportation. The performance test results showed that the refrigerated container could maintain the fish temperature below 3 0C for 3.8 hours. The container temperature without load reaches 11.1 0C to 15.5 0C for 120 minutes and the COP volue of refrigerated container was 0.33. Organoleptic value of fish after transport activities ranged from 7.1 to 7.3 and TPC value ranged from
Keyword: container transportation, thermoelectric cooler, fresh fish, polyurethane, fish traders

Judul: Penentuan Nilai Eigen dan Vektor Eigen dari Matriks Tridiagonal 2-Toeplitz dengan Pendekatan Polinomial Chebyshev
Abstrak: The eigenvalues and eigenvectors of a matrix can be determined by finding its characteristic polynomials. The characteristic polynomials of a tridiagonal 2-Toeplitz matrix is shown to be closely connected to polynomials which satisfy the Chebyshev recurrence relationship. If the order of the matrix is odd, then the eigenvalues are found explicitly in terms of the Chebyshev zeros and the eigenvectors are found in terms of the polynomials satisfying the recurrence relationship. For even ordered matrices, the situation is more complicated. The problem in these cases is that although the Chebyshev recurrence formula is still applied, its initial values are not generating Chebyshev polynomials
Keyword: