• Title/Summary/Keyword: Koc

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REMARKS ON GENERALIZED JORDAN (α, β)*-DERIVATIONS OF SEMIPRIME RINGS WITH INVOLUTION

  • Hongan, Motoshi;Rehman, Nadeem ur
    • Communications of the Korean Mathematical Society
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    • v.33 no.1
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    • pp.73-83
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    • 2018
  • Let R be an associative ring with involution * and ${\alpha},{\beta}:R{\rightarrow}R$ ring homomorphisms. An additive mapping $d:R{\rightarrow}R$ is called an $({\alpha},{\beta})^*$-derivation of R if $d(xy)=d(x){\alpha}(y^*)+{\beta}(x)d(y)$ is fulfilled for any $x,y{\in}R$, and an additive mapping $F:R{\rightarrow}R$ is called a generalized $({\alpha},{\beta})^*$-derivation of R associated with an $({\alpha},{\beta})^*$-derivation d if $F(xy)=F(x){\alpha}(y^*)+{\beta}(x)d(y)$ is fulfilled for all $x,y{\in}R$. In this note, we intend to generalize a theorem of Vukman [12], and a theorem of Daif and El-Sayiad [6], moreover, we generalize a theorem of Ali et al. [4] and a theorem of Huang and Koc [9] related to generalized Jordan triple $({\alpha},{\beta})^*$-derivations.

ON PSEUDO 2-PRIME IDEALS AND ALMOST VALUATION DOMAINS

  • Koc, Suat
    • Bulletin of the Korean Mathematical Society
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    • v.58 no.4
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    • pp.897-908
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    • 2021
  • In this paper, we introduce the notion of pseudo 2-prime ideals in commutative rings. Let R be a commutative ring with a nonzero identity. A proper ideal P of R is said to be a pseudo 2-prime ideal if whenever xy ∈ P for some x, y ∈ R, then x2n ∈ Pn or y2n ∈ Pn for some n ∈ ℕ. Various examples and properties of pseudo 2-prime ideals are given. We also characterize pseudo 2-prime ideals of PID's and von Neumann regular rings. Finally, we use pseudo 2-prime ideals to characterize almost valuation domains (AV-domains).

Study on Pesticide Runoff from Soil Surface-III - Runoff of Pesticides by Simulated Rainfall in the Laboratory - (농약의 토양 표면유출에 관한 연구-III - 실내에서 인공강우에 의한 농약의 유출특성 -)

  • Yeom, Dong-Hyuk;Kim, Jeong-Han;Lee, Sung-Kyu;Kim, Yong-Hwa;Park, Chang-Kyu;Kim, Kyun
    • Applied Biological Chemistry
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    • v.40 no.4
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    • pp.334-341
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    • 1997
  • In the laboratory experiment, concentration and rate of runoff of 7 pesticides were measured under the simulated rainfall. Total runoff rate of metolachlor, alachlor, chlorothalonil, chlorpyrifos, EPN, phorate and captafol were 57.0, 14.2, 13.2, 7.9, 7.2, 7.1 and 2.8%, respectively, and the average runoff concentrations were 940, 399, 55, 7.0, 9.3, 151 and 7.0 ppb, respectively. Significant relationship was observed between the runoff rate and water solubility in the laboratory experiment(r=0.923). Even though not very high, relatively significant results were obtained in other experimental conditions. Based on the results, runoff rate prediction$[Y=0.2812{\times}10exp(0.261logWS-0.366)+0.3594{\times}10exp(-0.545logKoc+1.747)+0.3594{\times}10exp(-0.362log\;Kow+1.105]$ and conversion equations were calculated to investigate the possibility of estimating runoff rate in the field by natural rain. Calculated runoff rate by conversion equation was similar to experimental result with captafol in the field while 6 times higher result was obtained by the prediction equation. Therefore, those prediction and conversion equations derived from the laboratory experiment data and physicochemical properties of the pesticides could be used for the prediction of field runoff rate of pesticides by natural rainfall.

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Adsorption Pattern of the Herbicide, Bentazon and Its Metabolites on Soil (제초제 Bentazon과 그 대사산물들의 토양 중 흡착양상)

  • Kim, Jong-Soo;Kim, Jang-Eok
    • Korean Journal of Environmental Agriculture
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    • v.28 no.3
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    • pp.274-280
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    • 2009
  • In order to elucidate the adsorption mechanism of the herbicide, bentazon and its metabolites on soil, their adsorption patterns on soil and six adsorbents were investigated with Freundlich, Langmuir and linear isotherm. Freundlich constants ($K_f$) and maximum adsorption amount($Q^0$) of bentazon on soil was 0.55 and 3.97. Kd and Koc values of it were 0.18 and 18. The all of metabolites used except deisopropylbentazon amounts sorbed on the soil were much higher than bentazon. The most of 8-hydroxybentazon was adsorbed on soil showing $K_f$ = 316.6, $Q^0$ = 3,488, Kd = 29.7 and Koc = 2,970. Bentazon, deisopropylbentazon and 8-hydroxybentazon were shown high affinity to anion exchange regardless of pH and $NH_2$ in low pH range. Reversed phase $C_{18}$ resulted in 100% retention of N-methylbentazon regardless of pH and other metabolites were retained below 40%. The AIBA was strongly adsorbed in silica gel, COOH and cation exchange phase but poor retention was on anion exchange sorbent. 2-Aminobenzoic acid showed an amphipathic nature which had high affinity for COOH and cation exchange phase at pH 7.0 as well as $NH_2$ and anion exchange sorbent at pH 3.0.

Thoracic Re-irradiation for Locally Recurrent Lung Cancer

  • Aktan, Meryem;Kanyilmaz, Gul;Koc, Mehmet;Aras, Serhat
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.11
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    • pp.5041-5045
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    • 2016
  • Background: Patients with recurrent or progressive lung cancer experience a significant symptom burden, negatively affecting quality of life and reducing life expectancy. Thoracic re-irradiation can be used for palliative treatment to relieve symptoms or as a curative treatment. Methods: Using patient charts, we identified and reviewed 28 cases that had received palliative thoracic re-irradiation for recurrent lung cancer. Results: Before re-irradiation, 32% of patients had stage III non-small cell lung cancer and six had small cell lung cancer. The median interval between treatments was 18.7 months. Median follow-up was 31.2 months from the initial radiotherapy and 5 months after re-irradiation. A better performance status before re-irradiation (<80 vs >80, p=0.09) and a lower overlap 90% isodose (<70 vs >70, p=0.09) showed trends toward improved survival. Grade 1-2 toxicity from re-irradiation was recorded in 12/28 patients, and no grade 3 or 4 acute toxicity was encountered. Conclusion: The role of palliative treatment in survival is not clear but it can provide symptomatic relief in patients, with no high grade toxicity. Further studies with greater patient numbers and longer follow-up times should facilitate determination of the role of this treatment in toxicity and effects on survival.

A Study on the Characteristics of Windmill Type Ultrasonic Motor (풍차형 초음파 모터의 특성 연구)

  • Lee, Jae-Hyung;Park, Tae-Gone
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2003.07b
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    • pp.636-640
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    • 2003
  • As industrial technology was developed, necessity for small size motor was increased on various fields such as medical treatment and robotics. The motor should be simple structure, and it has easy process of manufacture to overcome the limit of miniaturization. So, "the windmill type ultrasonic motor" is enough to satisfy these conditions. In this paper, windmill type ultrasonic motor which was proposed by B.Koc and K.Uchino, was analyzed and fabricated with modified endcap shape. Displacements of arms of the proposed endcap were compared with the previous endcap, using the finite element analysis program (ANSYS). Better rotational characteristics was expected in proposed model as result of FEA. Experimentally, rotary motors of 3.5 [cm] diameter were fabricated, and the speed and torque of the motor were measured. As a result, speed and torque were changed in proportion to the electrical input voltages. And low efficiency which was different from an expectation was obtained in this motor. So, various problems should be improved for practical use.

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Image Restoration by Lifting-Based Wavelet Domain E-Median Filter

  • Koc, Sema;Ercelebi, Ergun
    • ETRI Journal
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    • v.28 no.1
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    • pp.51-58
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    • 2006
  • In this paper, we propose a method of applying a lifting-based wavelet domain e-median filter (LBWDEMF) for image restoration. LBWDEMF helps in reducing the number of computations. An e-median filter is a type of modified median filter that processes each pixel of the output of a standard median filter in a binary manner, keeping the output of the median filter unchanged or replacing it with the original pixel value. Binary decision-making is controlled by comparing the absolute difference of the median filter output and the original image to a preset threshold. In addition, the advantage of LBWDEMF is that probabilities of encountering root images are spread over sub-band images, and therefore the e-median filter is unlikely to encounter root images at an early stage of iterations and generates a better result as iteration increases. The proposed method transforms an image into the wavelet domain using lifting-based wavelet filters, then applies an e-median filter in the wavelet domain, transforms the result into the spatial domain, and finally goes through one spatial domain e-median filter to produce the final restored image. Moreover, in order to validate the effectiveness of the proposed method we compare the result obtained using the proposed method to those using a spatial domain median filter (SDMF), spatial domain e-median filter (SDEMF), and wavelet thresholding method. Experimental results show that the proposed method is superior to SDMF, SDEMF, and wavelet thresholding in terms of image restoration.

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Turkish Social Attitudes towards to Cancer Prevention: a Health Belief Model Study

  • Tasci-Duran, Emel;Koc, Sukran;Korkmaz, Medet
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.18
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    • pp.7935-7940
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    • 2014
  • This research was planned to reveal society's attitude towards cancer and early diagnosis using the health belief model. This study was planned as descriptive research in Isparta. A random sample of n=256 individuals of both genders was recruited at the largest shopping center. As a means of collection tool, a survey consisted of two forms, the first designed for sociodemographic information and the second covering 29 questions suitable for the content of Health Belief Model. Of the participants, 66.8% were female and 33.2% were male, and the average age was $33.3{\pm}11.0$ years. Some 46.1% partly thought that they may develop cancer, and 49.6% were afraid of this possibility. As many as 50% indicated that cancer is an issue that comes from Allah. A significant difference was found between not going for control unless feeling bad, and blood analysis for cancer screening (${\chi}^2=3.780$ p= 0.03). It was seen that in an area with a high rate of cancer, people's awareness of cancer prevention and early diagnosis and attitudes towards these are insufficient.

Histological analysis of acute toxicity of 2,4-diclorophenoxy acetic acid in ovary of zebrafish

  • Koc, Nazan Deniz;Akbulut, Cansu
    • Animal cells and systems
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    • v.16 no.5
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    • pp.400-407
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    • 2012
  • Plant growth regulators are the chemicals that are found in plants and produced synthetically. In agricultural applications, plant hormones are used in minor quantities for fixing the problems. In our research, we studied the effects of 2,4 diclorophenoxyacetic acid (2,4D), which is an auxin used in agricultural applications. Auxins are the group that are used most popularly in plant growth regulators. In our study, different doses of 2,4 diclorophenoxyacetic acid are given to zebrafish, and ovarium tissues are observed histomorphologically. We generated one control and three experiment groups from the stock solution. The experiment was carried out in 20 liter capacity complete glass aquarium at $24{\pm}1^{\circ}C$ water temperature. After five days of application, fishes were dissected. Histomorphological changes of the ovarium were investigated under a light microscope. A decrease in the number of oocytes in zebrafish ovarium was observed when compared with the control group. Many deformed and underdeveloped oocytes were detected. An increase in the number of atretic oocytes was observed. It was deduced that acute doses of 2,4 diclorophenoxyacetic acid decelerates oogenesis in fishes.

High Transmission Rate of Germline Chimerism Using Cultured Primordial Germ Cells in Chickens.

  • Song, Gwon-Hwa;Park, Tae-Sub;Kim, Duk-Kyung;Kim, Jin-Nam;Lee, Young-Mok;Kim, Ki-Dong;Han, Jae-Yong
    • Proceedings of the Korea Society of Poultry Science Conference
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    • 2000.11a
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    • pp.88-90
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    • 2000
  • Although primordial germ cells(PGCs) have been used in the production of germline chimera, efficiency has not been satisfactory. The Present study was conducted to improve efficiency of germline chimera production using the cultured gonadal PGCs(gPGCs). Germline chimeric chickens were produced by transfer of cultured gonadal primordial germ cells from Korean Ogol Chicken (KOC) to White Leghorn (5.5-day-old) and cultured in vitro for 10 days. Approximately 200 gPGCs (2-day-old) recipient embryos from which blood had been withdrawn via the dorsal aorta prior to the injection. Recipient embryos were incubated until hatching. Germline chimerism of the chickens reaching maturity was examined by mating them with Korean Ogol Chicken. Donor-derived offspring were identified as germline chimeric chickens based on their feather color. The frequency of germline transmission of donor PGCs ranged 1.9∼60.7%. There was no difference between both sexes. Therefore, it can be concluded that efficiency of germline chimerism can be improved via using cultured gPGCs.

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