Chromatic Adaptation Transforms to Accommodate Printed Color Matching in Paper with Optical Brightening Agents (OBA)

2012 ◽  
Vol 200 ◽  
pp. 632-636
Author(s):  
Quan Hui Tian ◽  
Zhen Liu

The color reproduction is based on visual perception. The psychophysics experiments present the light source; illuminants and view background affect the results of color matching. Paper is a typical substrate for printed color matching and effects printed color greatly. Now almost all of print papers contain optical brightening agents, which changes significantly the color appearance of printed color and makes color shifting of printed color matching. This paper used CAT02 chromatic adaptation models to transform the measurements of printed color in paper with and without OBA, compared the effect of printed color matching between before and after transforming with display, present the method using chromatic adaptation transforms to improve the accurate of printed color matching.

2019 ◽  
Vol 2019 (1) ◽  
pp. 23-27
Author(s):  
Shining Ma ◽  
Peter Hanselaer ◽  
Kees Teunissen ◽  
Kevin A.G. Smet

Over the years, various chromatic adaptation transforms have been derived to fit the visual perception. However, some research demonstrated that CAT02, the most widely used chromatic adaptation transform, overestimates the degree of adaptation, especially for colored illumination. In this study, a memory color matching experiment was conducted in a real scene with the background adapting field varying in field of view, luminance and chromaticity. It showed that a larger field of view results in more complete adaptation. The results were used to test several existing chromatic adaptation models and to develop three new types of models. All of them improved the performance to some extent, especially for the illuminations with low CCT.


2014 ◽  
Vol 852 ◽  
pp. 648-652
Author(s):  
Xiao Zhou Li ◽  
Yu Liu ◽  
Jing Jing Liu ◽  
Xue Lin Li ◽  
Ai Xu

Chromatic adaptation is one of the primary causes of color appearance phenomena. It is the core foundation to develop color appearance model and the chief application. Chromatic adaptation is an important step in color reproduction process and an important physiological and psychological process. The basic principles of chromatic adaptation and chromatic adaptation transform were studied in detail based on the color appearance modeling principles. And the related viewing conditions were also studied in this paper. The research helps to make a deeper understanding to color appearance phenomena in color reproduction and to develop and to modify the color reproduction adaptation models under different viewing conditions. It plays an important role in improving the chromatic adaptation accuracy and color reproduction quality.


Author(s):  
Nazom Murio ◽  
Roseli Theis

Geometri adalah bagian matematika yang sangat dekat dari siswa, karena hampir semua objek visual yang ada di sekitar siswa adalah objek geometri, tetapi tidak semua siswa menyukai pembelajaran yang menyertakan gambar, sehingga memungkinkan siswa mengalami kesulitan dalam belajar geometri. Tujuan dari penelitian ini adalah untuk menggambarkan kesulitan belajar siswa berdasarkan karakteristik Lerner dalam menyelesaikan pertanyaan geometri. Jenis penelitian ini adalah penelitian deskriptif kualitatif. Subjek penelitian adalah siswa dengan kepribadian wali yang mengalami kesulitan belajar di kelas IX A SMP N 30 Muaro Jambi. Instrumen yang digunakan dalam penelitian ini adalah penulis sendiri, lembar tes klasifikasi kepribadian, lembar tes kesulitan belajar, dan pedoman wawancara. Hasil penelitian menunjukkan siswa dengan kepribadian wali yang mengalami kesulitan belajar, 100% mengalami kelainan persepsi visual, di mana siswa mengalami kesulitan dalam menentukan seperti apa bangun datar pada masalah tersebut. 60% mengalami kesulitan mengenali dan memahami simbol, di mana siswa melihat simbol "//" sebagai simbol untuk kesesuaian. Serta 40% mengalami kesulitan dalam bahasa dan membaca, di mana siswa kesulitan dalam memahami pertanyaan yang diberikan.   Geometry is a very close mathematical part of the student, because almost all visual objects that exist around the students are objects of geometry, but not all students like learning that includes images, thus allowing students to have difficulty in learning geometry. The purpose of this research is to describe students' learning difficulties based on Lerner's characteristic in solving the geometry question. This type of research is descriptive qualitative research. Research subjects were students with guardian personality who had difficulty studying in class IX A SMP N 30 Muaro Jambi. Instruments used in this study are the authors themselves, personality classification test sheets, learning difficulties test sheets, and interview guidelines. The results showed students with guardian personality who experienced learning difficulties, 100% experienced visual perception abnormalities, where students have difficulty in determining what kind of flat wake on the matter. 60% have difficulty recognizing and understanding symbols, where students see the symbol "//" as a symbol for conformity. As well as 40% have difficulty in language and reading, where students difficulty in understanding the given question.


2019 ◽  
Vol 2019 (1) ◽  
pp. 320-325 ◽  
Author(s):  
Wenyu Bao ◽  
Minchen Wei

Great efforts have been made to develop color appearance models to predict color appearance of stimuli under various viewing conditions. CIECAM02, the most widely used color appearance model, and many other color appearance models were all developed based on corresponding color datasets, including LUTCHI data. Though the effect of adapting light level on color appearance, which is known as "Hunt Effect", is well known, most of the corresponding color datasets were collected within a limited range of light levels (i.e., below 700 cd/m2), which was much lower than that under daylight. A recent study investigating color preference of an artwork under various light levels from 20 to 15000 lx suggested that the existing color appearance models may not accurately characterize the color appearance of stimuli under extremely high light levels, based on the assumption that the same preference judgements were due to the same color appearance. This article reports a psychophysical study, which was designed to directly collect corresponding colors under two light levels— 100 and 3000 cd/m2 (i.e., ≈ 314 and 9420 lx). Human observers completed haploscopic color matching for four color stimuli (i.e., red, green, blue, and yellow) under the two light levels at 2700 or 6500 K. Though the Hunt Effect was supported by the results, CIECAM02 was found to have large errors under the extremely high light levels, especially when the CCT was low.


2019 ◽  
Vol 2019 (1) ◽  
pp. 237-242
Author(s):  
Siyuan Chen ◽  
Minchen Wei

Color appearance models have been extensively studied for characterizing and predicting the perceived color appearance of physical color stimuli under different viewing conditions. These stimuli are either surface colors reflecting illumination or self-luminous emitting radiations. With the rapid development of augmented reality (AR) and mixed reality (MR), it is critically important to understand how the color appearance of the objects that are produced by AR and MR are perceived, especially when these objects are overlaid on the real world. In this study, nine lighting conditions, with different correlated color temperature (CCT) levels and light levels, were created in a real-world environment. Under each lighting condition, human observers adjusted the color appearance of a virtual stimulus, which was overlaid on a real-world luminous environment, until it appeared the whitest. It was found that the CCT and light level of the real-world environment significantly affected the color appearance of the white stimulus, especially when the light level was high. Moreover, a lower degree of chromatic adaptation was found for viewing the virtual stimulus that was overlaid on the real world.


Healthcare ◽  
2021 ◽  
Vol 9 (3) ◽  
pp. 312
Author(s):  
Marijana Sinđić ◽  
Draženka Mačak ◽  
Nikola Todorović ◽  
Bianka Purda ◽  
Maja Batez

Integrated neuromuscular training (INT) showed benefits for improving fundamental movement skills (FMS). However, the INT health-related fitness (HRF) effects are lacking. The current study aimed to determine the effects of INT implemented during physical education (PE) in a primary school in the Republic of Serbia on HRF in female children. The sample consisted of 72 healthy girls who were divided into the intervention (EG: n = 37; mean ± SD: age = 8.17 ± 0.31) and control (CG: n = 35; age = 8.11 ± 0.31) groups. The EG and CG performed the INT program and traditional PE activities two times per week within the first ~15 min of PE class, respectively. The Fitnessgram battery tests assessed the HRF (body composition, cardiorespiratory endurance, muscular fitness, and flexibility) before and after the program. After eight weeks, the EG significantly reduced all fat measures, while the CG decreased only triceps skinfold but to a smaller extent (F = 5.92, p < 0.02, ŋ2 = 0.09). Both groups significantly improved the performance of almost all muscular fitness tests (curl-ups, trunk lift, push-ups); however, the EG increased the push-ups more than the CG (F = 9.01, p < 0.01, ŋ2 = 0.14). The EG additionally improved the modified pull-ups (F = 14.09, p < 0.01, ŋ2 = 0.19) and flexed arm hang (F = 28.82, p < 0.01, ŋ2 = 0.33) tests. The flexibility and cardiorespiratory endurance of both groups did not significantly change after eight weeks. This approach of exercise showed positive acceptance and relatively good results after only eight weeks.


2021 ◽  
Vol 13 (15) ◽  
pp. 8316
Author(s):  
Camelia Mirela Baba ◽  
Constantin Duguleană ◽  
Marius Sorin Dincă ◽  
Liliana Duguleană ◽  
Gheorghița Dincă

The Covid-19 induced economic crisis has significantly affected almost all businesses from nearly every sector, causing severe financial problems, lack of cash assets, and decrease of revenues. In this context, the economic entities were forced to look for adjustment and rescue solutions of their activities. One possible solution for the recovery and reorganization of economic entities’ activities is demerger. This paper evaluates the impact of demerger upon the sustainable development of economic entities in terms of economic efficiency and financial performances. To achieve this goal, a statistical analysis of profitability ratios before and after the demerger, as well as a structural analysis of 268 demerger projects for the April 2012–April 2021 period, were performed. The results attest there are no significant differences between the ex-ante and ex-post financial performances. However, demerger seems to have a positive effect upon analyzed companies helping them to overcome economic hardships, rethink their business strategies, and continue their activity in the medium and long-term time horizon.


2015 ◽  
Vol 29 (5) ◽  
pp. 397-404 ◽  
Author(s):  
Jon Cornwall ◽  
Jodyanne Kirkwood ◽  
Gavin J. Clark ◽  
Stephen Silvey ◽  
Ruth D. Appleby ◽  
...  

The SEED (Student Enterprise Experience in Dunedin) programme was developed as a four-week, intensive entrepreneurial ‘boot camp’ to provide a small group of participants with a highly experiential business course. Using pre-course and post-course surveys, the authors measured the entrepreneurial ability, knowledge and intentions of the sixteen SEED participants to determine whether the programme was successful as an educational format. The results showed that perceived entrepreneurial ability and knowledge significantly improved, while intent increased but not significantly. Almost all participants intended to start a business both before and after the course, while twice as many (six) indicated that they would undertake further formal study in entrepreneurship after the course compared to before. The data suggest that SEED is filling a niche in entrepreneurial development and support for budding entrepreneurs, with the course also facilitating local business development.


Cephalalgia ◽  
2006 ◽  
Vol 26 (10) ◽  
pp. 1192-1198 ◽  
Author(s):  
P Zeeberg ◽  
J Olesen ◽  
R Jensen

It is generally accepted that ongoing medication overuse nullifies the effect of prophylactic treatment, although few data support this contention. We set out to describe the treatment outcome in patients withdrawn from medication overuse and relate any improvement to a renewed effect of prophylaxis. For patients with probable medication-overuse headache (pMOH), treated and dismissed from the Danish Headache Centre in 2002 and 2003, we assed, from prospective headache diaries, the headache frequency before and after withdrawal of offending drugs and compared these frequencies with the headache frequency at dismissal. Among 1326 patients, 337 had pMOH. Eligible were 175, mean age 49 years, male/female ratio 1: 2.7. Overall, there was a 46% decrease in headache frequency from the first visit to dismissal ( P < 0.0001). Patients with no improvement 2 months after complete drug withdrawal ( N = 88) subsequently responded to pharmacological and/or non-pharmacological prophylaxis with a 26% decrease in headache frequency as measured from the end of withdrawal to dismissal ( P < 0.0001). At dismissal, 47% were on prophylaxis. Former non-responders to medical prophylaxis had a 49% decrease in headache frequency from first visit to dismissal ( P < 0.0001), whereas those who had never received prophylaxis had a 56% reduction ( P < 0.0001). This difference was not statistically significant ( P = 0.22). Almost all MOH patients benefit from drug withdrawal, either just from the withdrawal or by transformation from therapeutic non-responsiveness to responsiveness. According to the International Classification of Headache Disorders, 2nd edn, the MOH diagnosis requires improvement after drug withdrawal. Our data suggest that these diagnostic criteria are too strict.


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