• Journal of the Institute of Electronics Engineers of Korea SD
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• v.41 no.12
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• pp.21-26
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• 2004

In this paper, a direct method is developed to extact RF equivalent circuit of a packaged BJT without optimization. First, parasitic components of plastic package are removed from measured S-parameters using open and short package patterns. Using package do-embedded S-parameters, a direct and simple method is proposed to extract bonding wire inductance and chip pad capacitance between package lead and chip pad. The small-signal model parameters of internal BJT are next determined by Z and Y-parameter formula derived from RF equivalent circuit. The modeled S-parameters of packaged BJT agree well with measured ones, verifying the accuracy of this new extraction method.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.52 no.2
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• pp.74-79
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• 2003

The method of the analysis of the base Gummel number of the BJT(Bipolar Junction Transistor) for integrated circuits based upon the semiconductor physics is proposed and the method of calculating the doping profile of the base region using process conditions is presented. The transistor saturation current obtained from the proposed method of NPN BJT using 20V and 30V process shows an averaged relative error of 6.7% compared with the measured data and the transistor saturation current of PNP BJT shows an averaged relative error of 9.2% compared with the measured data

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.52 no.2
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• pp.67-73
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• 2003

The algorithm (or calculating the base-collector breakdown voltage of NPN BJT(Bipolar Junction Transistor) for integrated circuits is Proposed. The method for calculating the electric field using the solution of Poisson's equation is presented and the method for calculating the breakdown voltage using the integration of ionization coefficients is presented. The base-collector breakdown voltage of NPN BJT using 20V process obtained from the proposed method shows an averaged relative error of 8.0% compared with the measured data and the base-collector breakdown voltage of NPN BJT using 30V process shows an averaged relative error of 4.3% compared with the measured data

• Journal of Physiology & Pathology in Korean Medicine
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• v.19 no.1
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• pp.106-113
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• 2005

Asthma is an inflammatory disease of airways that is induced by Th2 cytokines and inhibited by Th1 cytokines. In this study we wanted to investigate the effect of SCT and BJT on eosinophilla and cytokines of BALF in a mouse model established airway inflammmation. Asthma was induced to male c57/bl6 mice. Allergen-specific antibody responses, cytokine$(IL-4,\;IL-5,\;INF-{\gamma})$, and eosinophil inflammation of the airways were investigated on the BALF and splenocyte. SCT and BJT effectively induced $INF-{\gamma}$ and inhibited IL-4, IL-5 as well as eosinophilic inflammation when SCT and BJT were administered. Total Ig E level in the BALF decreased. SCT was more effectiveness than BJT. It is considered that SCT and BJT have faborable effect on the asthma because the asthma specific series of abnormalities in respiratory system were decreased.

• Journal of IKEEE
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• v.6 no.2 s.11
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• pp.119-127
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• 2002

An algorithm for analyzing the characteristics of the power BJT using numerical analysis method is proposed. The Fermi-Dirac statistics is used to calculate the carrier concentration in highly doped region. Philips Unified mobility model, SRH model and Auger model is used to calculate the recombination current of base region. To verify the accuracy of the proposed method, the collector current of BANDIS is compared with the measured data in the condition of the base current increased from $1.0[{\mu}A]\;to\;3.5[{\mu}A]$. The collector current of BANDIS show a maximum relative error within 8.9% compared with the measured data.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.19 no.3
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• pp.93-98
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• 2005

Silicon bipolar transistors (Si-BJT) are widely used in the telecommunication system such as short range wireless control and wireless indoor voice communication system. New modeling method for the internal current source model of Si-BJT is proposed. The proposed method based on new thermal resistance extraction method and new analytical expressions for the current source parameters of Si-BJT. The proposed method can directly extract the model parameters without any optimization procedure which is adopted in the conventional modeling method. The proposed method is applied to 5 finger $0.4\times20[{\mu}m^2]$ and the model shows good prediction of the measured data in $3[\%]$ of errors proving the validity of this method.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.23 no.1
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• pp.260-269
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• 2010

Background : Bojungikgitang(BJT) and Banhabaekchulchonmatang(BBT) are known to treat the tinnitus patients, which were registered Korean National Health Insurance coverage lists. Objective : Few studies have evaluated economic benefits of both herbal medicines. This research is to investigate the cost-effectiveness of Bojungikgitang(BJT) and Banhabaekchulchonmatang(BBT) in chronic tinnitus patients over nineteen years old. Method : We built the decision tree model of chronic tinnitus and executed the deterministic analysis and threshold sensitivity analysis based on randomized clinical trial. Effectiveness was measured in quality-adjusted life-years(QALYs), and costs were in 2009 KRW(South Korean Currency). The perspective is societal, time horizon is 10 weeks, and Korean willingness to pay threshold is assumed to 20,000,000KRW. Results : In the base case analysis, BJT treatment resulted is better outcomes as low cost, so BJT is dominant medicine and BBT is dominated. But both cost per QALYs (BJT is 3,120,339KWN per QALY, BBT is 3,505,780KWN per QALY) are lower than the threshold, that could be covered by Korean National Health Insurance(KNHI). Conclusion : This study results showed that BJT was more cost-effective than BBT treating tinnitus patients for 10 weeks, and the cost per QALYs of both alternatives were lower than Korean national threshold.

• Journal of Radiation Protection and Research
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• v.40 no.2
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• pp.110-117
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• 2015

Recently, Due to the increased industry using radiation inspection equipment in the semiconductor, this demand of technology research is increasing. Although semiconductor inspection equipment is using low energy X-ray from 40 keV to 120 keV, Studies of radiation damage about the low energy X-ray are lacking circumstance in our country. Therefore, It is study that BJT (bipolar junction transistor) of one type of semiconductor elements are received radiation damage by low energy X-ray. BJT were used to the NXP semiconductor company's BC817-25 (NPN type), and Used the X-ray generator for the irradiation. Radiation damage of BJT was evaluated that confirm to analyse change of collector-emitter voltage of before and after X-ray irradiation when current gain fixed to 10. X-ray generator of tube voltage was setting 40 kVp, 60 kVp, 80 kVp, 100 kVp, 120 kVp and irradiation time was setting 180s, 360s, 540s into 180s intervals. As the result, We confirmed radiation damage in BJT by low energy X-ray under 120 keV energy, and Especially the biggest radiation damage was appeared at the 80 kVp. It is expected that ELDRS (enhanced low dose rate sensitivity) phenomenon occurs on the basis of 80 kVp. This studies expect to contribute effective dose administration of semiconductor inspection equipment using low energy X-ray, Also Research and Development of X-ray filter.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.40 no.6
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• pp.16-23
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• 2003

In this paper, we propose an efficient bias circuit of discrete BJT component for hearing aid. The collector feedback bias circuit, widely used for the hearing aid, has a resistor for negative feedback. As the resistor affects AC and DC simultaneously, it is quite difficult to adjust amplifier gain without changing DC bias point. The previous bias circuit also has weak point to be oscillated by the positive feedback of power noise if gain of hearing aid is high. In the proposed circuit, we can reduce the two weak points of the previous circuit by adding a resistor to the collector feedback bias circuit between base and power supply which is $\beta$ times target than the collector resistor. Thus. we can change amplifier gain without changing DC bias point, and reduce power noise gain about 18.5% compare to that of tile previous circuit in the simulation.

• Proceedings of the IEEK Conference
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• 2003.07b
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• pp.763-766
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• 2003

A direct parameter extraction method using several two-port parameter equations derived in cutoff and active bias modes has been studied to obtain an accurate Gummel-Poon BJT model. First, dc model parameters were extracted from slopes and y-axis intercepts of I-V curve and Gummel plot. The pad capacitances and junction capacitance parameters were determined by using measured S-parameter sets in the cutoff bias. The resistance and transit time parameters were extracted by using measured S-parameter sets in the active bias.