Noise reduction studies for the Cessna model 337 (0-2) airplane

A study was undertaken to determine the noise reduction potential of the 0-2 airplane in order to reduce its aural detection distance. Static and flyover noise measurements were made to document the noise signature of the unmodified airplane. The results show that significant reductions in aural detection distance can be achieved by the combination of propeller geometry changes and the addition of engine exhaust mufflers. The best results were estimated for the aircraft equipped with a six-blade propeller operating at 3/4 engine speed in combination with a 3.49 cubic foot exhaust muffler installed on each engine. Detection distance for the modified aircraft is estimated to be reduced from about 4-1/4 miles to about 1-1/2 miles when the aircraft is operating at an altitude of 1,000 ft over grassy terrain. Reducing the altitude to 300 ft over a leafy jungle ground cover should reduce the aural detection distance to 0.9 miles. Reduced aural detection distances were also indicated for a modification utilizing a direct-drive six-blade propeller of reduced radius along with smaller exhaust mufflers

The nuclear scissors mode within two approaches (Wigner function moments versus RPA)

Two complementary methods to describe the collective motion, RPA and Wigner function moments method, are compared on an example of a simple model - harmonic oscillator with quadrupole-quadrupole residual interaction. It is shown that they give identical formulae for eigenfrequencies and transition probabilities of all collective excitations of the model including the scissors mode, which here is the subject of our special attention. The exact relation between the variables of the two methods and the respective dynamical equations is established. The normalization factor of the "synthetic" scissors state and its overlap with physical states are calculated analytically. The orthogonality of the spurious state to all physical states is proved rigorously.Comment: 39 page

Integrating biofortified crops into community development programs

Extensive research has demonstrated the effectiveness and acceptability of biofortification. There is now a need to establish effective, sustainable delivery systems for biofortified crops in countries with a high burden of micronutrient malnutrition. This requires country-level partnerships between national governments, non-governmental organizations (NGOs), the private sector and research institutions. World Vision (WV) is an international NGO with experience integrating biofortified crops as an agriculture-for-nutrition intervention within rural development projects, most extensively in Mozambique, Burundi, and Uganda. In WV’s experience, successful integration and uptake of biofortified crops within broader community development programs is reliant on key elements of both the enabling environment and the program design. The optimal mix and intensity of interventions is not yet known; implementation science research is needed to enhance understanding of the critical elements of successful adoption, intensification, scale-up and sustainability of biofortified crops, and the human, technical and financial resources required to achieve this and to contribute to the sustainable reduction of micronutrient malnutrition.Keywords: nutrition, agriculture, biofortification, integration, multi-sectoral, nutrition-sensitive, nutrition policy, micronutrients, diet diversificatio

The Effects of Sulfur and Micronutrients on Sunflower

The objective of the study reviewed was to determine the effect of sulfur zinc iron, copper, manganese, and boron on sunflower grown under field conditions. In times when farmers are struggling to maintain profitability, the proper management of macronutrients and micronutrients may mean the difference between profit and loss

Noise characteristics of the O-1 airplane and some approaches to noise reduction

A brief study of the O-1A airplane to determine possible means for reducing the aircraft aural detection distance was conducted. This effort involved measuring the noise signature of the basic airplane, devising methods to attenuate the noise, and then estimating the effect of several selected modifications on the aural detection distance of the aircraft. A relatively simple modification utilizing a 6.5 ft diameter, six-blade propeller and including a muffler having a volume of 0.725 cu ft is indicated to reduce the aural detection distance of the O-1 aircraft from about 6 miles at an altitude of 1,000 ft and 2 to 3 miles at an altitude of 300 ft to approximately half these values. The flyover noise data suggest that routing the exhaust stacks up and over the wing would provide immediate noise reduction of about 5 dB with an attendant reduction in detection distance. Furthermore, all these studies confirm the work of other investigators that the 1/3 octave band (center frequency=125 cps) is the most critical in reducing aural detection distance

Noise reduction studies for the U-10 airplane

A study was undertaken by the NASA Langley Research Center to determine the noise reduction potential of the U-10 airplane in order to reduce its aural detection distance. Static and flyover noise measurements were made to document the basic airplane noise signature. Two modifications to the airplane configuration are suggested as having the best potential for substantially reducing aural detection distance with small penalty to airplane performance or stability and control. These modifications include changing the present 3-blade propeller to a 5-blade propeller, changing the propeller diameter, and changing the propeller gear ratio, along with the use of an engine exhaust muffler. The aural detection distance corresponding to normal cruising flight at an altitude of 1,000 ft over grassy terrain is reduced from 28,000 ft (5.3 miles) to about 50 percent of that value for modification 1, and to about 25 percent for modification 2. For the aircraft operating at an altitude of 300 ft, the analysis indicates that relatively straightforward modifications could reduce the aural detection distance to approximately 0.9 mile. Operation of the aircraft at greatly reduced engine speed (1650 rpm) with a 1.3-cu-ft muffler provides aural detection distances slightly lower than modification 1

The effect of operations on the ground noise footprints associated with a large multibladed, nonbanging helicopter

In order to expand the data base of helicopter external noise characteristics, a flyover noise measurement program was conducted utilizing the NASA Civil Helicopter Research Aircraft. The remotely operated multiple array acoustics range (ROMAAR) and a 2560-m linear microphone array were utilized for the purpose of documenting the noise characteristics of the test helicopter during flyby and landing operations. By utilizing both ROMAAR concept and the linear array, the data necessary to plot the ground noise footprints and noise radiation patterns were obtained. Examples of the measured noise signature of the test helicopter, the ground noise footprint or contours, and the directivity patterns measured during level flyby and landing operations of a large, multibladed, nonbanging helicopter, the CH-53, are presented

Dampak KUPS terhadap Kinerja UKM Peternak Sapi Studi Kasus di Lembang, Jawa Barat

Dalam rangka pemberdayaan Usaha Kecil Menengah (UKM), penciptaan lapangan kerja, dan penanggulangan kemiskinan, pemerintah menerbitkan Paket Kebijakan yang bertujuan meningkatkan Sektor Riil dan memberdayakan UKM. Kebijakan pengembangan dan pemberdayaan UKM salah satunya adalah peningkatan akses pada sumber pembiayaan. Salah satu sektor UKM adalah USAha pembibitan sapi yang menghasilkan daging dan susu sapi.Untuk mewujudkan swasembada dalam pengadaan daging dan susu sapi, Kementerian Pertanian menerbitkan PERATURAN MENTERI PERTANIAN NOMOR : 40/Permentan/PD.400/9/2009, tentang PEDOMAN PELAKSANAAN KREDIT USAHA PEMBIBITAN SAPI. Kemudian dilanjutkan dengan keputusan Menteri Keuangan pada tahun yang sama yang menetapkan besarnya bunga pinjaman 5% untuk KUPS tersebut. Sebagai langkah implementasinya telah ditunjukan juga sebanyak 11 bank pemerintah sebagai pelaksana, yaitu Bank BRI, Bank BNI, Bank Bukopin, Bank Mandiri, Bank BPD Sumut, Bank BPD Sumbar, Bank BPD Jateng, Bank BPD DIY, Bank BPD Jatim, Bank BPD Bali, dan Bank BPD NTB.Penelitian ini bertujuan untuk mendapatkan pemahaman yang lengkap mengenai implementasi KUPS, serta dampak KUPS terhadap kinerja peternak sapi. Untuk itu dilakukan tahap eksplorasi penyaluran dan penggunaan KUPS di pelaku peternak sapi. Penyaluran KUPS akan menyangkut mekanisme dan prosedurnya, sedangan penggunaan KUPS menyangkut aspek manfaat terhadap pengembangan USAhanya.Pemahaman yang lebih mendalam dilakukan melalui tahap eksplanatori, yaitu eksplorasi kriteria/faktor keberhasilan/kegalan implementasi KUPS, penjelasan tentang pengaruh KUPS terhadap kinerja dan pengembangan USAhanya.Kajian ditingkat kebijakan. Program pengembangan perbibitan merupakan suatu hal yang harus segera ditangani oleh pemerintah dalam mendukung program PSDSK. Program reguler untuk mendukung PSDSK tahun 2014 melalui pengembangan USAha pembibitan yang telah difasilitasi oleh pemerintah antara lain program skim Kredit Usaha Pembibitan Sapi (KUPS) dan Aksi Perbibitan dan APBNP. Hal ini bertujuan untuk menjadikan kelompok peternak mandiri serta dapat memanfaatkan sumber pendanaan dan pelayanan dalam upaya peningkatan skala USAha, pengetahuan dan keterampilan teknologi pembibitan.Kajian ditingkat organisasi. KPSBU Lembang ( Koperasi Peternak Sapi Bandung Utara ), adalah koperasi primer tunggal USAha di kecamatan Lembang yang merupakan suatu wadah bagi para petani peternak sapi perah dengan wilayah kerja Koperasi Peternak Sapi Bandung Utara. Program KUPS yang dibuat oleh pemerintah sebagai salah satu dukungan pemerintah dalam memajukan peternak sapi di Jawa Barat belum bisa menerapkan secara maksimal. Dimana sosialisasi sama sekali tidak dilakukan.Kajian ditingkat operasional. Peternak sapi dilingkungan KPSBU pada umumnya tidak mengakses KUPS. Kendala yang umum adalah kurangnya sosialisasi dari Pemerintah ataupun dari pihak bank penyelenggara

33.8 GHz CCS Survey of Molecular Cores in Dark Clouds

We have conducted a survey of the CCS $J_N = 3_2-2_1$ line toward 11 dark clouds and star-forming regions at 30 arcsec spatial resolution and 0.054 km/s velocity resolution. CCS was only detected in quiescent clouds, not in active star-forming regions. The CCS distribution shows remarkable clumpy structure, and 25 clumps are identified in 7 clouds. Seven clumps with extremely narrow nonthermal linewidths < 0.1 km/s are among the most quiescent clumps ever found. The CCS clumps tend to exist around the higher density regions traced by NH_3 emission or submillimeter continuum sources, and the distribution is not spherically symmetric. Variation of the CCS abundance was suggested as an indicator of the evolutionary status of star formation. However, we can only find a weak correlation between N(CCS) and $n_{H_2,vir}$. The velocity distributions of CCS clouds reveal that a systematic velocity pattern generally exists. The most striking feature in our data is a ring structure in the position-velocity diagram of L1544 with an well-resolved inner hole of 0.04 pc x 0.13 km/s and an outer boundary of 0.16 pc x 0.55 km/s. This position-velocity structure clearly indicates an edge-on disk or ring geometry, and it can be interpreted as a collapsing disk with an infall velocity $\gtrsim$ 0.1 km/s and a rotational velocity less than our velocity resolution. Nonthermal linewidth distribution is generally coherent in CCS clouds, which could be evidence for the termination of Larson's Law at small scales, $\sim$ 0.1 pc.Comment: 21 pages, 25 ostscript figures, accepted for publication in the Supplement Series of the Astrophysical Journal (May 2000