Power computation for the triboelectric nanogenerator

We consider, from a mathematical perspective, the power generated by a contact-mode triboelectric nanogenerator, an energy harvesting device that has been well studied recently. We encapsulate the behaviour of the device in a differential equation, which although linear and of first order, has periodic coefficients, leading to some interesting mathematical problems. In studying these, we derive approximate forms for the mean power generated and the current waveforms, and describe a procedure for computing the Fourier coefficients for the current, enabling us to show how the power is distributed over the harmonics. Comparisons with accurate numerics validate our analysis

Routine repeat head CT may not be necessary for patients with mild TBI.

Background:Routine repeat cranial CT (RHCT) is standard of care for CT-verified traumatic brain injury (TBI). Despite mixed evidence, those with mild TBI are subject to radiation and expense from serial CT scans. Thus, we investigated the necessity and utility of RHCT for patients with mild TBI. We hypothesized that repeat head CT in these patients would not alter patient care or outcomes. Methods:We retrospectively studied patients suffering from mild TBI (Glasgow Coma Scale (GCS) score 13-15) and treated at the R Adams Cowley Shock Trauma Center from November 2014 through January 2015. The primary outcome was the need for surgical intervention. Outcomes were compared using paired Student's t-test, and stratified by injury on initial CT, GCS change, demographics, and presenting vital signs (mean ± SD). Results:Eighty-five patients met inclusion criteria with an average initial GCS score=14.6±0.57. Our center sees about 2800 patients with TBI per year, or about 230 per month. This includes patients with concussions. This sample represents about 30% of patients with TBI seen during the study period. Ten patients required operation (four based on initial CT and others for worsening GCS, headaches, large unresolving injury). There was progression of injury on repeat CT scan in only two patients that required operation, and this accompanied clinical deterioration. The mean brain Abbreviated Injury Scale (AIS) score was 4.8±0.3 for surgical patients on initial CT scan compared with 3.4±0.6 (P<0.001) for non-surgical patients. Initial CT subdural hematoma size was 1.1±0.6 cm for surgical patients compared with 0.49±0.3 cm (P=0.05) for non-surgical patients. There was no significant difference between intervention groups in terms of other intracranial injuries, demographics, vital signs, or change in GCS. Overall, 75 patients that did not require surgical intervention received RHCT. At $340 per CT,$51 000 was spent on unnecessary imaging ($367 000/year, extrapolated). Discussion:In an environment of increased scrutiny on healthcare expenditures, it is necessary to question dogma and eliminate unnecessary cost. Our data questions the use of routine repeat head CT scans in every patient with anatomic TBI and suggests that clinically stable patients with small injury can simply be followed clinically. Level of evidence:Level III

ANALISIS PERBANDINGAN TENAGA KERJA LOKAL DAN TENAGA KERJA LUAR DALAM JASA KONSTRUKSI DI MANADO (STUDI KASUS: TRANSMART)

Dalam dunia jasa konstruksi, produktivitas tenaga kerja adalah salah satu faktor penentu keberhasilan sebuah proyek pembangunan. Tingkat produktivitas tenaga kerja dapat diukur dengan meneliti besarnya tingkat LUR (Labour Utilitation Rate) masing-masing pekerja, yaitu meneliti seberapa besar tingkat efektivitas pekerja dalam bekerja. Besarnya tingkat produktivitas tenaga kerja dipengaruhi oleh banyak faktor, seperti umur, pengalaman kerja, tingkat pendidikan, kesesuaian upah, kesehatan pekerja, dan hubungan antar pekerja, Penelitian ini bertujuan untuk membandingkan tingkat produktivitas tenaga kerja lokal dan tenaga kerja dari luar daerah, serta untuk mengetahui pengaruh umur, pengalaman kerja, tingkat pendidikan, kesesuaian upah, kesehatan pekerja, dan hubungan antar pekerja, terhadap tingkat produktivitas tenaga kerja. Penelitian dilakukan pada proyek pembangunan Transmart. Penelitian dilakukan dengan cara mengamati tingkat produktivitas 30 tenaga kerja dan disertai pengisian kuesioner. Pengamatan tingkat produktivitas (LUR) dilakukan pada masing-masing pekerja. Setelah pengumpulan data, baik data produktivitas dan kuesioner, selanjutnya dilakukan proses pengolahan data dengan bantuan program komputer. Kata kunci: Jasa konstruksi, tenaga kerja, produktivitas, efektivitas, LU

Perbandingan Biaya Proyek Gedung Empat Lantai STKIP Kie Raha Ternate Dengan Metode Earned Value

Pada setiap proyek diperlukan tindakan pengendalian dari segi biaya dan waktu. Akan tetapi sebelum dilakukan tindakan pengendalian biaya dan waktu, perlu diketahui terlebih dulu kinerja proyek yang telah berlangsung. Dengan salah satu cara inilah kita mendapati perbandingan diantara dua nilai yang akan dianalisa. Salah satu cara untuk mengetahui kinerja proyek adalah metode Earned Value. Metode Earned Value memadukan unsur jadwal, biaya dan prestasi kerja. Analisa Earned Value ini akan diterapkan pada proyek Proyek Pembangunan Kantor Pusat Administrasi STKIP Kie Raha di Ternate. Kinerja proyek dianalisa berdasarkan indeks performansi biaya dan waktu. Perhitungan didasarkan pada data biaya yang dianggarkan untuk pekerjaan yang direncanakan (Planned Value), biaya yang dianggarkan untuk pekerjaan yang telah dilaksanakan (Earned Value) dan biaya yang telah dikeluarkan (Actual Cost). Hasil analisa pada minggu ke - 7 menunjukkan bahwa biaya yang dikeluarkan lebih rendah dari biaya yang dianggarkan atau waktu pelaksanaan lebih cepat dari jadwal rencana yang ditunjukkan dengan nilai CPI = 1,1079 (CPI > 1) dan SPI = 1.0424 (SPI >1). Hasil perhitungan Earned Value didapati bahwa perbandingan biaya proyek yang direncanakan dengan biaya yang dihasilkan dari perhitungan earned value ialah Rp. 693,194,966,00. Dimana dalam perencanaan biaya yang dianggarkan ialah Rp. 16,551,242,600,00. Sedangkan biaya yang didapat dari perhitungan earned value ialah Rp 15,858,047,634,0

Teaching Health Occupations for a Networked World

This paper discusses the problems with traditionally managed hierarchies and observes that networking among units is becoming more prevalent. Given the . interdependence inherent in fully networked organizations, systems thinking is introduced as a useful tool for understanding and managing change. Health Occupations Educators can use systems thinking skills to help students comprehend (a) how and why systems interrelate to help patients, (b) how to build and maintain relationships, (c) how to synthesize information across content areas, and (d) how to learn

Luminous radio-quiet sources in the W3(MAIN) cloud core

We have resolved 450 micrometer and 800 micrometer emission from the W3(Main) star forming region into three major peaks, using 8 inch - 14 inch beams with the James Clerk Maxwell Telescope on the summit of Mauna Kea. One of the submillimeter sources is identified with W3 - IRS5, a well-known candidate protostar. However, to our surprise, we find that none of the submillimeter peaks coincides with any of the prominent compact HII regions in the area. We estimate that the three submillimeter sources together contribute 30-50 percent of the total bolometric luminosity of the region, and speculate that the contribution of luminous radio-quiet sources to the total luminosity of HII region/molecular cloud complexes may be larger than is often assumed

FAKTOR-FAKTOR YANG MEMPENGARUHI PROFIT KONTRAKTOR PADA PROYEK KONSTRUKSI

Pada dasarnya pembangunan bertujuan untuk meningkatkan kesejahteraan atau kualitas hidup manusia ke arah yang lebih baik dengan cara memanfaatkan sumber daya yang tersedia di sekitar lingkungan hidupnya . Keberhasilan pembangunan pada pelaksanaan suatu proyek konstruksi dalam mencapai tujuan yang di rencanakan memerlukan sumber daya di antaranya waktu, dana, teknologi, manusia dan material. Manajemen Konstruksi menjadi salah satu penggerak pada area pembangunan. Dalam dunia manajemen konstruksi, nilai upah dari pekerja proyek merupakan salah satu faktor yang sangat penting dalam perencanaan proyek Sementara penyediaan material, peralatan dan Faktor keuangan pada sebuah proyek pembangunan jika tidak mengalami hambatan akan sangat menunjang proses pada sebuah pembangunan itu sendiri. karakteristik lapangan yang ideal akan berpengaruh pada proses pembangunan pada sebuah proyek Kata kunci : tenaga kerja, material, peralatan, karakteristik lapangan, profit kontrakto

Network Landscape from a Brownian Particle's Perspective

Given a complex biological or social network, how many clusters should it be decomposed into? We define the distance $d_{i,j}$ from node $i$ to node $j$ as the average number of steps a Brownian particle takes to reach $j$ from $i$. Node $j$ is a global attractor of $i$ if $d_{i,j}\leq d_{i,k}$ for any $k$ of the graph; it is a local attractor of $i$, if $j\in E_i$ (the set of nearest-neighbors of $i$) and $d_{i,j}\leq d_{i,l}$ for any $l\in E_i$. Based on the intuition that each node should have a high probability to be in the same community as its global (local) attractor on the global (local) scale, we present a simple method to uncover a network's community structure. This method is applied to several real networks and some discussion on its possible extensions is made.Comment: 5 pages, 4 color-figures. REVTeX 4 format. To appear in PR

Speech and communication in Parkinson’s disease: a cross-sectional exploratory study in the UK

Objective: To assess associations between cognitive status, intelligibility, acoustics and functional communication in PD. Design: Cross-sectional exploratory study of functional communication, including a within-participants experimental design for listener assessment. Setting: A major academic medical centre in the East of England, UK. Participants: Questionnaire data were assessed for 45 people with Parkinson’s disease (PD), who had self-reported speech or communication difficulties and did not have clinical dementia. Acoustic and listener analyses were conducted on read and conversational speech for 20 people with PD and 20 familiar conversation partner controls without speech, language or cognitive difficulties. Main outcome measures: Functional communication assessed by the Communicative Participation Item Bank (CPIB) and Communicative Effectiveness Survey (CES). Results: People with PD had lower intelligibility than controls for both the read (mean difference 13.7%, p=0.009) and conversational (mean difference 16.2%, p=0.04) sentences. Intensity and pause were statistically significant predictors of intelligibility in read sentences. Listeners were less accurate identifying the intended emotion in the speech of people with PD (14.8% point difference across conditions, p=0.02) and this was associated with worse speaker cognitive status (16.7% point difference, p=0.04). Cognitive status was a significant predictor of functional communication using CPIB (F=8.99, p=0.005, η2 = 0.15) but not CES. Intelligibility in conversation sentences was a statistically significant predictor of CPIB (F=4.96, p=0.04, η2 = 0.19) and CES (F=13.65, p=0.002, η2 = 0.43). Read sentence intelligibility was not a significant predictor of either outcome. Conclusions: Cognitive status was an important predictor of functional communication—the role of intelligibility was modest and limited to conversational and not read speech. Our results highlight the importance of focusing on functional communication as well as physical speech impairment in speech and language therapy (SLT) for PD. Our results could inform future trials of SLT techniques for PD