Transmisi Gelombang Pada Breakwater Tenggelam

. Beach damages in the form of beach erosion, has been made problems in many countries. For solving the problem, the experts have been developed many kinds of structure, as revetment, grion and detached breakwater. Although a part of the structure succeed to restrain the beach erosion, but generally it is not friendly environmental, especially from the tourism view. This paper try to develop friendly environmental beach protection, by taking the coral characteristic, in the form of submerged breakwater. The analysis is focused in the capability of the submerged breakwater in reducing the incident waves, which be approahed by the relation of wave steepness Hi/gT2 versus transmission coefficient Ct = Ht /Hi , for certain b/L and d/h. The result is wave transmission figures, which show that the bigger value of b/L or d/h the smaller value of Ct

HUBUNGAN KELIMPAHAN SPESIES LARVA IKAN DENGAN PARAMETER KUALITAS PERAIRAN DI DANAU RANAU, SUMATERA SELATAN

This research conducted due to lack of information about fish larvae in Ranau Lake, South Sumatera. This information is quite essential to explore because this can be used as a scientific basis for policy formation in this area. The objectives of this research are to analyze the correlation between fish larvae abundance to physicochemical parameters in Ranau Lake waters. Sampling was carried out at six stations (Muara Silabung, Dermaga, Way Maisin, Pemandian Air Panas, Lumbok, and Talang Teluk). Physico-chemical parameters measured directly in the field are temperature, pH, depth, brightness, CO2, O2, hardness, electrical conductivity, total alkalinity, and turbidity; while the chemical parameters measured in the laboratory are COD, NO2, NO3, NH3, and PO4. Larvae species identified through DNA sequence. Principal Component Analysis (PCA) was used to measure the relationship between fish larvae abundance to the water parameters. Results show that generally there were forty-two fish larvae from nine species. The dominant species was Oreochromis niloticus. The results of the Principal Component Analysis show that the highest abundance of fish larvae was in water with the highest level of turbidity and dissolved oxygen, whereas the lowest abundance was in water with the highest level nitrate and depth.   Belum ada informasi tentang kelimpahan larva ikan diperairan Danau Ranau Sumatera Selatan melatarbelakangi penelitian ini. Informasi ini sangat penting untuk diketahui karena dapat dijadikan acuan dalam pengelolaan perikanan di wilayah ini. Penelitian bertujuan untuk menganalisis hubungan kelimpahan larva ikan dengan parameter fisika-kimia di perairan Danau Ranau. Pengambilan sampel dilakukan di enam stasiun (Muara Silabung, Dermaga, Way Maissin, Pemandian Air Panas, Lumbok dan Talang Teluk). Parameter fisika-kimia perairan yang diukur langsung di lapangan adalah suhu, pH, kedalaman, kecerahan, CO2, O2, kesadahan, daya hantar listrik, total alkalinitas, dan turbiditas; sedangkan parameter kimia yang diukur di laboratorim adalah COD, NO2, NO3, NH3, dan PO4. Spesies larva ikan diidentifikasi dengan sekuen DNA. Analisis Komponen Utama dilakukan untuk mengetahui hubungan antara kelimpahan larva ikan dengan parameter fisika-kimia perairan. Hasil penelitian menunjukkan secara keseluruhan ada 42 larva ikan yang berasal dari 9 spesies. Spesies yang paling dominan adalah Oreochromis niloticus. Hasil Analisis Komponen Utama menunjukkan bahwa kelimpahan larva ikan tertinggi (102,9 individu/100m3) berada pada stasiun pengamatan yang memiliki turbiditas dan oksigen terlarut tertinggi, sedangkan kelimpahan larva ikan terendah (10,83 individu/100m3) berada pada stasiun pengamatan yang memiliki kadar nitrat dan kedalaman tertinggi

Finite element analysis of composite cylinder with centre cutout under axial load and internal pressure

Results from Finite Element (FE) study on the response of composite cylinder shells with cutouts and subjected to internal pressure and axial compression are presented. The objective of the study is to improving the buckling load by applying the internal pressure whilst the compression load is applied. The effect of localized stress concentration distributed around the cutout region also being examined. The numerical results are obtained using ABAQUS finite element code software package. The composite cylinder shells were tested in two conditions which are a combination of axial compression load with internal pressure and a single axial compression load. The effects of varying internal pressure and cutout size on the pre-buckling, buckling, and post-buckling responses of the shell are demonstrated. Reasonable results comparison was obtained by reviewing previous literature. Results indicated that the load distribution and displacement of the cutout significantly influence the structural response of the shell. The results also indicate that the stress distributions can be affected by the size of the cutout under axial compression load

Development of Building Heat Detection System: An Improvement Study

ABSTRACT- The increment of the numbers for accidents due to building safety system errors has created a serious disaster over the year. Due to that reason, this paper presents the entitled Building Heat Detection System (BHD System) by the objectives to develop the proper circuit in order to secure the detection device during the building fire attack. A BHD system, also known as fire protection system consists of heat sensing and monitoring system. The sensors detect extreme heat in an area or zone; the control unit processes the signals and sets off evacuation alarms to alert building occupants. This study focused on the design and fabrication of the system prototype to demonstrate the operation of a BHD system in case of fire accidents. Hose reel indicator is included to display the exact location in a building to aid in firefighting. On top of that, exit indicators were added to show the available exits should fire breaks out in a building. This study is hoped to help the system engineers to improve and secure their building safety system in the future

Wildlife Species as Potential Sources of Human Exposure to Parasitic Pathogens in Accra, Ghana

Handling and consumption of wildlife species pose risks of exposure to the infective stages of parasitic pathogens and disease transmission. This study assessed protozoan and helminth infections in some wildlife species commonly consumed as meat in Accra, Ghana. Using Zinc Sulphate centrifugal flotation and microscopic techniques, seven protozoan species (Entamoeba sp., Giardia sp., Iodamoeba sp., Cryptosporidium sp., Balantidium sp., Endolimax sp. and Eimeria sp.) and 11 genera of intestinal helminths including Haemonchus, Trichostrongylus, Ascaris, Monieza, Schistosoma and Trichuris were identified. Kruskal-Wallis tests showed significant difference in intensity of protozoan [χ2(3) = 11.59; p = 0.009] and helminth [χ2(3) = 31.41; p < 0.0001] infections among the four groups of wildlife species. For protozoans, the differences were observed between the mean cyst and oocyst (Cryptosporidium sp.) intensities of Maxwell’s Duiker and Bushbuck (U = 5, p = 0.006) as well as Grasscutter and Bushbuck (U = 3, p = 0.004). However, the differences in mean helminth egg intensities were observed between Grasscutter and Maxwell’s Duiker (U = 6, p < 0.0001), Grasscutter and Bushbuck (U = 16, p < 0.0001) as well as Grasscutter and Royal Antelope (U = 4, p < 0.0001). The results highlight the need for awareness of the risks of parasitic diseases as a prerequisite for their effective prevention

Initial Screening of Fast-growing Tree Species Being Tolerant of Dry Tropical Peatlands in Central Kalimantan, Indonesia

An investigation of the recruit, survivorship and growth of naturally regenerating tree species on canal bank was conducted to select tree species which are suitable for preceding planting in drained and burnt peat swamp lands in Central Kalimantan, Indonesia. Top of the canal bank were open, with greater soil moisture deficit and higher soil temperatures than on the next intact forest floor. The abundant trees were asam-asam (Ploiarium alternifolium),garunggang (Cratoxylon arborescens) and tumih (Combretocarpus rotundatus). New regeneration of these trees on the canal bank was confirmed during this investigation and mortality was very low. These results indicated that P. alternifolium,C. arborescens and C. rotundatuswere tolerant of intensive radiation, soil drought and high soil temperatures during germination. The annual height increments were 189-232 cm y-1 (P. alternifolium),118-289 cm y-1 (C. arborescens)and 27-255 cm y-1 (C. rotundatus); thus, these three species could be classified as fast-growing with tolerance to open and dry conditions. Such characteristics were important to avoid competition with herbs, ferns,and/ or climbers. The results·suggest that P.alternifolium,C. arborescens and C. rotundatusare suitable for preceding planting for the rehabilitation of the disturbed peat swamp forests of Central Kalimantan