• Title/Summary/Keyword: Light Curve

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Research on the Financial Data Fraud Detection of Chinese Listed Enterprises by Integrating Audit Opinions

  • Leiruo Zhou;Yunlong Duan;Wei Wei
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.17 no.12
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    • pp.3218-3241
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    • 2023
  • Financial fraud undermines the sustainable development of financial markets. Financial statements can be regarded as the key source of information to obtain the operating conditions of listed companies. Current research focuses more on mining financial digital data instead of looking into text data. However, text data can reveal emotional information, which is an important basis for detecting financial fraud. The audit opinion of the financial statement is especially the fair opinion of a certified public accountant on the quality of enterprise financial reports. Therefore, this research was carried out by using the data features of 4,153 listed companies' financial annual reports and audits of text opinions in the past six years, and the paper puts forward a financial fraud detection model integrating audit opinions. First, the financial data index database and audit opinion text database were built. Second, digitized audit opinions with deep learning Bert model was employed. Finally, both the extracted audit numerical characteristics and the financial numerical indicators were used as the training data of the LightGBM model. What is worth paying attention to is that the imbalanced distribution of sample labels is also one of the focuses of financial fraud research. To solve this problem, data enhancement and Focal Loss feature learning functions were used in data processing and model training respectively. The experimental results show that compared with the conventional financial fraud detection model, the performance of the proposed model is improved greatly, with Area Under the Curve (AUC) and Accuracy reaching 81.42% and 78.15%, respectively.

Understanding the Response Characteristics of X-ray Verification Film (X-선 Verification 필름의 반응 특성에 관한 연구)

  • Yeo Inhwan;Seong Jinsil;Chu Sung Sil;Kim Gwi Eon;Suh Chang Ok;Burch Sandra E.;Wang Chris K.
    • Radiation Oncology Journal
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    • v.16 no.4
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    • pp.505-515
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    • 1998
  • Purpose : This study is intended to understand the sensitometric characteristics and the emulsion properties of the commercially available CEA TVS film in comparison with the Kodak X-Omat V film. Materials and Methods : For this purpose, we have formulated an analytic expression of the characteristic curves for x-ray film exposed to mixed radiation of electrons, photons, and visible light. This mathematical expression was developed based on reaction-rate and target-hit theories. Unlike previous expressions. it relates optical density to emulsion properties such as grain size and silver bromide content We have also developed a quantity which characterizes the film response to visible light relative to that to photons and electrons. This quantity could be expressed as a function of grain area. Thus, we have developed mathematical expressions and quantities with which the emulsion properties of the films can be revealed based on the sensitometric characteristics. Demonstrating the use of this analytical study, we exposed CEA and Kodak verification films to the mixed radiation of electrons, photons, and visible light, and interpreted the experimental results accordingly. Results : We have demonstrated that: (1) the saturation density increases as the silver bromide content increases, (2) the time required to reach the threshold dose (to which the film begins to respond) when films are exposed to visible light decreases as the grain size increases, and (3) the CEA film contains more silver bromide. whereas the Kodak film contains larger grains. These findings were supported by the data provided by the manufacturers afterward. Conclusion : This study presented an analytical and experimental basis for understanding the response of X-ray film with respect to the emulsion properties.

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Analysis of Spatial and Vertical Variability of Environmental Parameters in a Greenhouse and Comparison of Carbon Dioxide Concentration in Two Different Types of Greenhouses (온실 환경요인의 공간적 및 수직적 특성 분석과 온실 종류에 따른 이산화탄소 농도 비교)

  • Jeong, Young Ae;Jang, Dong Cheol;Kwon, Jin Kyung;Kim, Dae Hyun;Choi, Eun Young
    • Journal of Bio-Environment Control
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    • v.31 no.3
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    • pp.221-229
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    • 2022
  • This study was aimed to investigate spatial and vertical characteristics of greenhouse environments according to the location of the environmental sensors, and to investigate the correlations between temperature, light intensity, and carbon dioxide (CO2) concentration according to the type of greenhouse. Temperature, relative humidity (RH), CO2, and light sensors were installed in the four-different vertical positions of the whole canopy as well as ground and roof space at the five spatial locations of the Venlo greenhouse. Also, correlations between temperature, light intensity, and CO2 concentration in Venlo and semi-closed greenhouses were analyzed using the Curve Expert Professional program. The deviations among the spatial locations were larger in the CO2 concentration than other environmental factors in the Venlo greenhouse. The average CO2 concentration ranged from 465 to 761 µmol·mol-1 with the highest value (646 µmol·mol-1) at the Middle End (4ME) close to the main pipe (50Ø) of the liquefied CO2 gas supply and lowest (436 µmol·mol-1) at the Left Middle (5LM). The deviation among the vertical positions was greater in temperature and relative humidity than other environments. The time zone with the largest deviation in average temperature was 2 p.m. with the highest temperature (26.51℃) at the Upper Air (UA) and the lowest temperature (25.62℃) at the Lower Canopy (LC). The time zone with the largest deviation in average RH was 1 p.m. with the highest RH (76.90%) at the LC and the lowest RH (71.74%) at the UA. The highest average CO2 concentration at each hour was Roof Air (RF) and Ground (GD). The coefficient of correlations between temperature, light intensity, and CO2 concentration were 0.07 for semi-closed greenhouse and 0.66 for Venlo greenhouse. All the results indicate that while the CO2 concentration in the greenhouse needs to be analyzed in the spatial locations, temperature and humidity needs to be analyzed in the vertical positions of canopy. The target CO2 fertilization concentration for the semi-closed greenhouse with low ventilation rate should be different from that of general greenhouses.

The Influence of Several Drugs Affecting $Ca^{2+}$ Influx on Frequency-tension Curve of Rat Left Atrium (쥐의 좌심방에서 세포막을 통한 $Ca^{2+}\;Flux$에 영향을 주는 약물이 자극빈도-장력 곡선에 미치는 영향)

  • Kim, Chan-Yun;Ahn, Sok-Kyun;Suh, Chang-Kook;Kang, Doo-Hee
    • The Korean Journal of Physiology
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    • v.23 no.2
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    • pp.329-337
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    • 1989
  • Cardiac muscles show stimulation frequency-dependent tension changes i.e. Bowditch phenomenon and Woodworth phenomenon, the former is an increase of tension with the increase of stimulation frequency, whereas the latter is an increase of tension with a decrease of stimulation frequency. Bowditch phenomenon is seen in the range of frequency 1.0 cps and above, and Woodworth phenomenon below the frequency 1.0 cps in the most of mammalian cardiac atrium. To throw some light on the possible mechanism of both phenomena in rat atrium, influences of drugs affecting $Ca^{2+}$ influx through the plasma membrane $(verapamil,\;La^{3+},\;norepinephrine)$ and $Ca^{2+}$ release from sarcoplasmic reticulum (SR) on frequency-tension curve were studied. The results obtained are summarized as follows: 1) At low temperature $(27.5^{\circ}C)$, both Bowditch and Woodworth phenomenon were demonstrated. But Bowditch phenomenon disappeared at the temperature above $(32.5^{\circ}C)$. 2) At $(27.5^{\circ}C)$, in the presence of verapamil, a $Ca^{2+}$ channel blocker, a time course of change in the frequency-tension was studied. It was found that Bowditch phenomenon was affected before the Woodworth phenomenon, then the former was completely disappeared. At $(32.5^{\circ}C)$, where no Bow-ditch is seen in normal atrial muscle, Bowditch phenomenon was reappeared by an administration of norepinephrine suggesting again that slow inward current of such as $Ca^{2+}$ channel is closely related to Bowditch phenomenon. 3) At $27.5^{\circ}C$, in the presence of $La^{3+}$, although tensions were decreased at all stimulation frequencies, Bowditch and Woodworth phenomenon were still demonstrated. However in the presence of both $La^{3+}$ and verapamil, Bowditch phenomena was disappeared suggesting that $La^{3+}$ is less effective in blocking $Ca^{2+}$ channel than verapamil. 4) At $27.5^{\circ}C$, in the presence of ryanodine, an inhibitor of calcium release from SR, Woodworth phenomenon was disappeared, which was consistent with previous reports of others, suggesting that $Ca^{2+}$ release from SR is closely related to Woodworth phenomenon. From the above findings, it may be concluded that Bowditch phenomenon is dependent on the magnitude of $Ca^{2+}$ influx through slow channel and Woodworth phenomenon is dependent on the amount of $Ca^{2+}$ stored in SR.

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Research on Optimizing Luminosity Factor Through Color Filter $Y_{1-X}G_X$, $Y_{1-X}P_X$ ($Y_{1-X}G_X$, $Y_{1-X}P_X$ 칼라필터를 통한 시감도 최적화 연구)

  • Kim, YongGeun;Park, Hyun-Ju
    • Journal of Korean Ophthalmic Optics Society
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    • v.14 no.1
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    • pp.47-56
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    • 2009
  • Purpose: To find optimized luminosity factor of color from light transmission filter. Methods: To make $Y_{1-x}G_{x}$, $Y_{1-x}P_{x}$ by using CR-39 compound within dipping method, mixing up Y(Yellow), G(green) and P(pink) for optimize eye sensitivity. Modeling for relative luminous efficiency(relative sensitivity) curves in Luminose transmission, it could be resolved by Multiplying sensitivity of eye within transmission rate of Lens ($P_f({\lambda}=T({\lambda}){\cdot}P({\lambda}).)$.). To evaluate Wavelength between 400~700 nm, relative luminous efficiency curve in Area and Height value is being used. Results: In color filter of $Y_{1-x}G_{x}$ position of x equals to 0.04, 0.1, 0.08, 0.12, 0.14, 0.5 at ${\beta}=S_1/S_0{\cdot}100$ each consist value of 76.1, 77.9, 80.7, 81.6, 80.2, 18.6 In color filter of $Y_{1-x}P_{x}$ position of x equals to 1.00, 0.2, 0.6, 0.8 at ${\beta}=S_1/S_0{\cdot}100$ each consist value of 74.3, 74.0, 70.5, 33.0 The result from experiment $Y_{1-x}P_{x}$ value less than $Y_{1-x}G_{x}$, from evaluating luminous efficiency curve and test was successfully optimized. Conclusions: Optimized relative luminous efficiency curve result have value of X=0.12-0.14 at $Y_{1-x}G_{x}$.

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Process design of superplastic forming/diffusion bonding by using pressure control (압력제어를 이용한 초소성 성형/확산접합의 공정설계)

  • Song, J.S.;Kang, K.Y.;Hong, S.S.;Kwon, Y.N.;Lee, J.H.;Kim, Y.H.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2007.05a
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    • pp.332-335
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    • 2007
  • The superplastic forming (SPF) has been widely used in the automotive and aerospace industry because it has great advantages to produce very light and strong components. Finite element method (FEM) is used to model the process of superplastic forming/diffusion bonding (SPF/DB), to predict the pressure-time curve and to analyze the process parameter. In this study, process design of SPF/DB is carried out a 3-sheet sandwich part. SPF/DB process with pressure control was analyzed by using finite element method. For obtaining proper shape, step-by-step pressurization is proposed. The first step of SPD/DB process is obtained by applying of pressure in patches. From the next step it applied pressure to all regions (between inner sheets, between inner and face sheets). By using the proposed pressurization scheme, deficit in part shape is found to be eliminated.

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OPTICAL MICROVARIABILITY OF BLAZARS

  • GHOSH K. K.;KIM CHULHEE;RAMSEY B. D.;SOUNDARARAJAPERUMAL S.
    • Journal of The Korean Astronomical Society
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    • v.34 no.1
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    • pp.9-15
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    • 2001
  • We present the results of optical differential photometry of five blazars [PKS0219+428 (3C66A), PKS 0235+164 (AO 0235+16), H0414+019, PKS 0851+202 (OJ 287) and QSO 1807+698 (3C 371)] that were observed on 7 nights between November 05, 1997 and December 29, 1998, using the B and the V band filters. We have detected microvariations in four blazars (3C66A, AO 0235+16, H04l4+019, and OJ 287). In addition, the light curve of AO 0235+16 has displayed a mini-flare when the brightness of this source was decreasing. Night-to-night variations have also been detected in 3C66A, H04l4+019, and OJ 287. The results of our observations are discussed in the framework of accretion disk phenomena (magnetic flares or hot spots in accretion disks) and jet phenomena (plasma instabilities in jets).

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Dyeing Properties and Antimicrobial Activity of Soybean Fiber with Gromwell Colorants (대두섬유에 대한 자초색소의 염색성 및 항균성)

  • Choi, Hee;Shin, Youn-Sook;Choi, Chang-Nam;Kim, Sang-Yool;Chung, Yong-Sik
    • The Korean Fashion and Textile Research Journal
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    • v.9 no.1
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    • pp.119-123
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    • 2007
  • Dyeing properties of soybean fabrics on gromwell colorants were studied for the effect of dyeing conditions, such as colorants concentration, temperature, time and pH on the dye uptake and effect of mordants on color change, dye uptake and various colorfastness. Antimicrobial activity of soybean fabrics dyed and sim-mordanted with gromwell colorants was examined by shake flask method. Gromwell colorants showed considerably affinity to soybean fabric and its isotherm adsorption curve was Freundlich type. Therefore, it is considered that hydrogen bonding and Van der Waals force were involved in the adsorption of gromwell colorants to soybean fabric. Soybean fabrics showed R color on Al, Cu and Sn mordant, RP color on Cr and Fe mordant, but soybean fabrics showed low dye uptake depending on mordanting treatment. Light colorfastness was increased for Cr and Fe mordants. Staphylococcus aureus reduction rates were above 90% for Cr and Cu mordanted soybean fabrics, and the others were poor. Klebsiella pneumoniae reduction rates soybean fabrics did not show reduction rate hardly.

An eBook Adoption Model Based on Smart Devices (스마트기기 기반의 전자책 수용 모형)

  • Jeon, Byeong Kug;Yoon, Mi Sun;Kim, Seung Ryeol
    • Journal of Information Technology Services
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    • v.13 no.4
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    • pp.255-273
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    • 2014
  • The widespread use of smart phones and smart pads has given rise to the use of eBook services based on these smart devices. Consequently, the size of eBook services has exploded both in the domestic as well as overseas market. However, the growth curve becomes flatter than before, and the adoption rate is still not high in Korea. Hence, this study explores the factors affecting the intention to use eBook services based on smart devices, and their relationships. Finally, we propose an eBook adoption model, which extends the Technology Adoption Model. An online survey was conducted to validate the research model. By applying Partial Least Squares, we found that there are strong relationships among perceived usefulness, perceived ease of use, perceived playfulness, social influence, and intention to use. In addition, we found that smart devices enjoyment positively affects the perceived playfulness of eBooks, and that personal innovativeness positively affects perceived ease of use. Our findings shed some light on how to design eBook services based on smart devices.

Preliminary Study on the Toxicity and Transfer of Heavy Metals and Tributyltin to Seagrass Zostera marina (잘피의 광합성에 대한 중금속 및 TBT의 독성 영향과 중금속 흡수에 대한 연구)

  • Choi, Tae-Seob;Kim, Kwang-Young;Lee, Byeong-Gweon;Lee, Jung-Suk
    • ALGAE
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    • v.20 no.2
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    • pp.157-166
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    • 2005
  • Uptake kinetics of Cd and Zn by leaves and rhizome of the seagrass Zostera marina were examined in controlled laboratory radiotracer experiments. Subsequently, acute toxicity of Cd, Cu and TBT on photosynthetic quantum yield (ΔF/Fm’ of Z. marina were determined, and the differential sensitivities of rapid light curve (RLC) to those harmful substances were also compared. All measurements on photosynthetic activity were determined by chlorophyll a fluorescence method using pulse amplitude modulation (PAM). Metal uptake by Z. marina was saturated with increasing exposure time in leaves and rhizomes. Uptake of Zn by Z. marina was faster than that of Cd. Metal uptake rates in Z. marina decreased with the increase of dissolved metal concentrations and also with the increase of biomass. The adverse effect of TBT on effective quantum yield was stronger than other pollutants. Average acute toxicity on the RLC of the seagrass exposed to TBT and two heavy metals (Cd and Cu) was going to decrease as follows: TBT > Cd > Cu. Our preliminary results in this study suggested that Z. marina potentially can be used as a biomonitor of harmful substances contamination in coastal waters.