area survey
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2021 ◽  
pp. 088740342110638
Author(s):  
T. R Kochel ◽  
Seyvan Nouri ◽  
S. Yaser Samadi

The study evaluates a geographically based focused deterrence (FD) intervention, extending knowledge about FD impact beyond crime data to also examine residents’ lived experiences with gangs and gun violence via a two-wave household survey. We employ a quasi-experimental design and utilize time-series analyses, coefficient difference tests, and mixed-effects ordinal logistic regression. The results show a significant reduction in shots fired incidents in the target area relative to comparison areas. Shots fired calls for service trended downward citywide, but the magnitude was doubled in the target area. Survey data showed substantive declines in the target area on all six gang and gun violence outcomes, significantly exceeding changes experienced in comparison areas. We conclude that focusing geographically as well as on repeat offenders is an effective FD approach, and evaluating community surveys provides an improved understanding of the community impact.


2021 ◽  
Vol 2 (9) ◽  
pp. 1663-1681
Author(s):  
Dio Mega Putri ◽  
Ahmad Perwira Mulia

Salah satu fungsi manajemen zona pantai adalah untuk menjaga kestabilan pantai sehingga sangat memerlukan data monitoring zona pantai. Namun, data monitoring dan penelitian tentang kondisi zona pantai dan perubahan garis pantai masih sedikit. Pesatnya perkembangan teknologi mengakibatkan pekerjaan survei dan pemetaan zona pantai kini dapat dilakukan dengan mudah, yaitu dengan menggunakan teknologi UAV. Penelitian ini bertujuan untuk menganalisis kondisi zona pantai berdasarkan ortofoto yang diambil oleh UAV yang dikontrol dengan menggunakan GPS Geodetik di lapangan dan menguraikan tahapan pembentukan fotogrametri dengan UAV hingga menghasilkan gambar ortofoto yang terkoreksi. Metodologi yang diterapkan dalam penelitian ini terdiri dari prasurvei, survei lapangan dan pasca survei. Tahapan awal penelitian meliputi persiapan teknis dan non teknis, pengamatan area survey dan melakukan studi referensi. Tahapan survei lapangan dilakukan untuk mengumpulkan data primer berupa hasil pengukuran Ground Control Point (GCP) dan pengambilan mosaik foto udara menggunakan UAV/Drone, mengambil foto dokumentasi lapangan, serta memenuhi kebutuhan survei lainnya. Tahapan pasca survei merupakan kegiatan pengolahan data foto udara serta pengolahan foto dokumentasi. Nilai ketentuan ketelitian geometri berdasarkan kelas (CE90 dan LE90) termasuk ke dalam kelas 1. Berdasarkan hasil perhitungan selisih jarak beberapa objek di foto pada komputer dan jarak sebenarnya di lapangan, diperoleh rata-rata persentase akurasi sebesar 97%. Hal tersebut menandakan bahwa pengukuran menggunakan UAV memiliki akurasi yang tinggi. UAV merupakan alat yang ideal untuk survei dan pemetaan zona pantai serta masalah pantai lainnya.


2021 ◽  
Vol 11 (5) ◽  
pp. 61-64
Author(s):  
Amira S. Khalafalla ◽  
Yousif A. Mohammed ◽  
Adam D. Abakar ◽  
A Mergani ◽  
Amer M. Dafaalla ◽  
...  

Background: Vitamin D plays a role in critical cellular processes such as apoptosis, cell development, and division. The Fok1 polymorphism in the VRD gene is T/C resulting in larger vitamin D receptor protein with lesser expression activity. Fok1 polymorphism is thought to be linked to many diseases including diabetes mellitus, cancers, and rheumatoid arthritis. The snipe also provides effective and sensitive diagnostic and predictive tools and affected by differences in ethnicity and individuals' life style. This study reports on the frequency and distribution of Fok1 SNP among healthy Sudanese transplantation donors. Method: This cross sectional study was conduct in National Cancer Institute University of Gezira, Sudan. One hundred and forty six healthy Sudanese transplantation donors were enrolled in this study. Two ml of venous blood was collected from each participant and stored at -20 till DNA extraction. Qaigen kit was used for DNA extraction. VDR Fok1 was genotyped by CTPP-PCR with proper primers designing and PCR condition. Data was collected by structured questionnaire and analyzed by SNP Stats online tool and medical calculator. Results: According to study results theFok1 polymorphism distributed among Sudanese with percentage of 49.9% (TT + CT), frequency of SNP variants was 69.8% regarding C allele and 30.2% for T allele, while the three genotypes was 10.2% for TT, 39.7% for TC and 50.1% for CC genotype. Conclusion: The frequency of Fok1 VDR SNP was high among healthy Sudanese transplantation donors, this necessitate the conduction of wide area survey among other healthy Sudanese population. This intern will help in investigating the nature of the relation of this SNP with other different diseases. Keywords: Vitamin D, Fok1rs. 2225870, VDR SNP, Sudanese


2021 ◽  
Author(s):  
Kamil Sobolewski

Abstract An international operating company detected a leak during an annual ROV inspection of a water injection (WI) pipeline offshore Angola in the Gulf of Guinea. The pipeline owner made the decision to repair the damaged line using clamps, but there were multiple challenges involved in executing the repair. First was the depth of the pipeline, which was on the seabed across an area that ranged from 1,170 m to 1,410 m (3,839 ft – 4,626 ft). Additional challenges included potential complications for clamp installation because of the location of the pipe welds and the physical condition of the pipe, which had experienced considerable wall thinning in multiple areas. Bringing the pipeline back into safe service required repairs to the aging pipe within a scope of work that included site preparation, the installation of two 12-in clamp connectors, and inspection services following clamp placement to verify proper installation. Because there were welds in the WI pipeline, there was a risk that the clamp installation site would correspond with an area of the pipe that was welded, which would impact the ability of the clamps to fit snugly over the damaged area. Survey data were cross-referenced with the client's data to determine that the weld locations would not interfere with the installation. Coating removal was critical, so a purpose-built mechanical tool was designed to prepare the pipeline for clamp installation. The project also required finite element analysis (FEA) to confirm that the pipeline could withstand the seal load applied by the repair clamps. The project was carried out in three steps. The objective of the first step was to prepare and stabilize the seabed to ensure it could bear the weight of the clamp installation frame and the impact of the ROV working nearby. The second phase focused on preparing the repair locations for installation of the clamps, a process that included coating removal and surface cleaning to return the WI pipeline to bare metal finish in the clamp areas. The third phase was the preparation and installation of the 12-in repair clamps. This included the inspection and spot cleaning of pipeline surfaces, clamp installation, and clamp seal verification. The two clamps were successfully installed and passed pressure testing in February 2020, enabling the operator to bring the WI line back online and functioning safely at reduced pressure. This repair employed the highest-pressure clamp of this type installed to date (138 bar / 2,000 psi).


Author(s):  
H. T. Zhao ◽  
W. C. Gao ◽  
C. F. Jing ◽  
X. F. Li

Abstract. With the development of technology and geospatial equipment, more and more work, particularly covering a big area survey and mapping work, are conducted with different worker and equipment, or heterogeneous time variation. With the traditional data quality focus on the geospatial data quality itself, which is not include the work files and organization. Facing the heterogeneous characteristics of geospatial data and work organization, a full life data quality workflow was proposed to manage and control geospatial data quality. The proposed workflow is extended to include the file preparation, quality evaluation, and quality calculation phrases. It is demonstrated in one real data quality project, which include vector data, raster data and other geospatial data covering 160 thousands square kilometers and 300 work zones finished by 8 teams. The usability and reliability were validated in our work.


Author(s):  
Connor Donegan ◽  
Yongwan Chun ◽  
Daniel A. Griffith

Epidemiologists and health geographers routinely use small-area survey estimates as covariates to model areal and even individual health outcomes. American Community Survey (ACS) estimates are accompanied by standard errors (SEs), but it is not yet standard practice to use them for evaluating or modeling data reliability. ACS SEs vary systematically across regions, neighborhoods, socioeconomic characteristics, and variables. Failure to consider probable observational error may have substantial impact on the large bodies of literature relying on small-area estimates, including inferential biases and over-confidence in results. The issue is particularly salient for predictive models employed to prioritize communities for service provision or funding allocation. Leveraging the tenets of plausible reasoning and Bayes’ theorem, we propose a conceptual framework and workflow for spatial data analysis with areal survey data, including visual diagnostics and model specifications. To illustrate, we follow Krieger et al.’s (2018) call to routinely use the Index of Concentration at the Extremes (ICE) to monitor spatial inequalities in health and mortality. We construct and examine SEs for the ICE, use visual diagnostics to evaluate our observational error model for the ICE, and then estimate an ICE–mortality gradient by incorporating the latter model into our model of sex-specific, midlife (ages 55–64), all-cause United States county mortality rates. We urge researchers to consider data quality as a criterion for variable selection prior to modeling, and to incorporate data reliability information into their models whenever possible.


2021 ◽  
Vol 502 (2) ◽  
pp. 3012-3020
Author(s):  
Y Uno ◽  
H Imai ◽  
K Shinano ◽  
H-H Qiao ◽  
J R Dawson ◽  
...  

ABSTRACT We have modelled the 3D distribution of OH/IR stars in the Galactic plane, traced by 1612 MHz OH maser sources with classic double horned spectral profiles. We statistically analysed over 700 maser sources detected by the HI/OH/Recombination line survey of the Milky Way (THOR) and the Australia Telescope Compact Array interferometric follow-up observations of the Southern Parkes Large-Area Survey in Hydroxyl (SPLASH). With a simple model constructed from a classical density distribution of stars and luminosity functions of OH maser sources in the Galaxy, we estimate the scale height, or the half thickness of the OH/IR star distribution along the Galactic disc to be 90–290 pc. The simple model also implies that there are ∼4000 OH/IR stars hosting 1612 MHz OH masers along the Galactic Plane. Therefore, next generation telescopes such as the Australian Square Kilometre Array Pathfinder (ASKAP) and SKA Phase 1 will detect about 80 per cent of such OH/IR stars in the Galaxy at a 10 mJy detection limit. Comparing the data of previously detected circumstellar 1612 MHz OH maser sources with those of THOR and SPLASH, the maser source lifetime is estimated to be ∼300 yr. This is likely a lower limit, since non-detections of masers in some cases could be affected by the flux variation of the maser source.


2021 ◽  
Vol 7 (7) ◽  
pp. 51-60
Author(s):  
Nikolay A. SOKOLOV ◽  
◽  
Andrey V. RYCHKOV ◽  
Grigori N. SHCHERBAKOV ◽  
Igor A. EFREMOV ◽  
...  

The advantages of using autonomous underwater vehicles in searching for ferromagnetic objects based on recording of spatially distributed magnetic anomalies are considered. The development lines of multichannel magnetometric search tools are shown. The potential capabilities of multichannel magnetometric systems for identifying search objects are revealed. Processing the survey results and drawing up a map of magnetic anomalies will make it possible to identify structures the geomagnetic properties of which differ essentially from the natural magnetic background. The use of such technique opens the possibility to achieve a significantly fuller information content and better reliability of the water area survey results and reveal visually undistinguished objects that have their own magnetic field. Based on the electromagnetic field and magnetostatics theory, a method for calculating the parameters and performance efficiency of the multichannel magnetometric system for autonomous underwater vehicles has been developed. The method is designed to evaluate the parameters of and capabilities for detecting ferromagnetic objects and to make a preliminary assessment of the search efficiency. The results obtained from computer simulation of the multichannel magnetometric system signals have confirmed the possibility of drawing up a map of magnetic anomalies to assess the occurrence depth and location of the search object in the ground. The shape of the search object magnetograms depends not only on the object type, but also on its orientation relative to the surface. By applying this dependence, it is possible to recognize search objects, determine their orientation and occurrence depth.


2020 ◽  
Vol 644 ◽  
pp. A160
Author(s):  
W.-J. Kim ◽  
F. Wyrowski ◽  
J. S. Urquhart ◽  
J. P. Pérez-Beaupuits ◽  
T. Pillai ◽  
...  

Aims. We study ten molecular transitions obtained from an unbiased 3 mm molecular line survey using the IRAM 30 m telescope toward 409 compact dust clumps identified by the APEX Telescope Large Area Survey of the Galaxy (ATLASGAL) to better understand the photodissociation regions (PDRs) associated with these clumps. The main goal of this study is to investigate whether the abundances of the selected molecules show any variations resulting from the PDR chemistry in different clump environments. Methods. We selected HCO, HOC+, C2H, c-C3H2, CN, H13CN, HC15N, and HN13C as PDR tracers, and H13CO+ and C18O as dense gas tracers. By using estimated optical depths of C2H and H13CN and assuming optically thin emission for other molecular transitions, we derived the column densities of those molecules and their abundances. To assess the influence of the presence and strength of ultra-violet radiation, we compare abundances of three groups of the clumps: HII regions, infrared bright non-HII regions, and infrared dark non-HII regions. Results. We detected C18O, H13CO+, C2H, c-C3H2, CN, and HN13C toward most of the observed dust clumps (detection rate >94%), and H13CN is also detected with a detection rate of 75%. On the other hand, HCO and HC15N show detection rates of 32 and 39%, respectively, toward the clumps, which are mostly associated with HII region sources: detection rates of HCO and HC15N toward the HII regions are 66 and 79%. We find that the abundances of HCO, CN, C2H, and c-C3H2 decrease as the H2 column density increases, indicating high visual extinction, while those of high-density tracers (i.e., H13CO+ and HC15N) are constant. In addition, N(HCO)/N(H13CO+) ratios significantly decrease as H2 column density increases, and, in particular, 82 clumps have X(HCO) ≳ 10−10 and N(HCO)/N(H13CO+) ≳ 1, which are indications of far-ultraviolet (FUV) chemistry. This suggests the observed HCO abundances are likely associated with FUV radiation illuminating the PDRs. We also find that high N(c-C3H2)/N(C2H) ratios found for HII regions that have high HCO abundances (≳10−10) are associated with more evolved clumps with high Lbol/Mclump. This trend might be associated with grain-surface processes, which determine the initial abundances of these molecules, and time-dependent effects in the clumps corresponding to the envelopes around dense PDRs and HII regions. In addition, some fraction of the measured abundances of the small hydrocarbons of the HII sources may be the result of the photodissociation of PAH molecules.


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