Characterizing Higgs portal dark matter models at the ILC

Kamon, Teruki,Ko, P.,Li, Jinmian Springer-Verlag 2017 European Physical Journal C Vol.77 No.9

<P>We study the dark matter (DM) discovery prospect and its spin discrimination in the theoretical framework of gauge invariant and renormalizable Higgs portal DM models at the ILC with root s = 500 GeV. In such models, the DM pair is produced in association with a Z boson. In the case of the singlet scalar DM, the mediator is just the SM Higgs boson, whereas for the fermion or vector DM there is an additional singlet scalar mediator that mixes with the SM Higgs boson, which produces significant observable differences. After careful investigation of the signal and backgrounds both at parton level and at detector level, we find the signal with hadronically decaying Z boson provides a better search sensitivity than the signal with leptonically decaying Z boson. Taking the fermion DM model as a benchmark scenario, when the DM-mediator coupling g(chi) is relatively small, the DM signals are discoverable only for benchmark points with relatively light scalar mediator H-2. The spin discriminating from scalar DM is always promising, while it is difficult to discriminate from vector DM. As for g(chi) approaching the perturbative limit, benchmark points with the mediator H-2 in the full mass region of interest are discoverable. The spin discriminating aspects from both the scalar and the fermion DM are quite promising.</P>

일본의 플라스틱 보드 드레인 발달의 역사와 과제 (Ⅱ)

가문아사(Kamon Masashi),추방정이(Suwa Seiji) 한국지반공학회 2006 지반 : 한국지반공학회지 Vol.22 No.5

일본의 플라스틱 보드 드레인 발달의 역사와 과제 (1)

가문아사(Kamon Masashi),추방정이(Suwa Seiji) 한국지반공학회 2006 지반 : 한국지반공학회지 Vol.22 No.4

Remediation of Contaminated Lands

Masashi Kamon 한국토목섬유학회 2008 한국토목섬유학회 학술발표회 Vol.2008 No.4

Low-Voltage-Stress AC-Linked Charge Equalizing System for Series-Connected VRLA Battery Strings

Charnyut Karnjanapiboon,Kamon Jirasereeamornkul,Veerapol Monyakul 전력전자학회 2013 JOURNAL OF POWER ELECTRONICS Vol.13 No.2

This paper presents a low voltage-stress AC-linked charge equalizing system for balancing the energy in a serially connected, valve-regulated lead acid battery string using a modular converter that consists of multiple transformers coupled together. Each converter was coupled through an AC- linked bus to increase the overall energy transfer efficiency of the system and to eliminate the problem of the unbalanced charging of batteries. Previous solutions are based on centralized and modularized topologies. A centralized topology requires a redesign of the hardware and related components. It also faces a high voltage stress when the number of batteries is expanded. Modularized solutions use low-voltage-stress, double-stage, DC-linked topologies which leads to poor energy transfer efficiency. The proposed solution uses a low-voltage stress, AC-linked, modularized topology that makes adding more batteries easier. It also has a better energy transfer efficiency. To ensure that the charge equalization system operates smoothly and safely charges batteries, a small intelligent microcontroller was used in the control section. The efficiency of this charge equalization system is 85%, which is 21% better than other low-voltage-stress DC-linked charging techniques. The validity of this approach was confirmed by experimental results.

Single-Stage High-Power-Factor Electronic Ballast with a Symmetrical Class-DE Resonant Rectifier

Chainarin Ekkaravarodome,Kamon Jirasereeamornkul 전력전자학회 2012 JOURNAL OF POWER ELECTRONICS Vol.12 No.3

This paper presents the use of a novel, single-stage high-power-factor electronic ballast with a symmetrical class-DE low-dυ/dt resonant rectifier as a power-factor corrector for fluorescent lamps. The power-factor correction is achieved by using a bridge rectifier to utilize the function of a symmetrical class-DE resonant rectifier. By employing this topology, the peak and ripple values of the input current are reduced, allowing for a reduced filter inductor volume of the EMI filter. Since the conduction angle of the bridge rectifier diode current was increased, a low-line current harmonic and a power factor near unity can be obtained. A prototype ballast, operating at an 84-㎑ fixed frequency and a 220-Vrms, 50-㎐ line input voltage, was utilized to drive a T8-36W fluorescent lamp. Experimental results are presented which verify the theoretical analysis.

Analysis and Implementation of a Half Bridge Class-DE Rectifier for Front-End ZVS Push-Pull Resonant Converters

Chainarin Ekkaravarodome,Kamon Jirasereeamornkul 전력전자학회 2013 JOURNAL OF POWER ELECTRONICS Vol.13 No.4

An analysis of the junction capacitance in resonant rectifiers which has a significant impact on the operating point of resonance circuits is studied in this paper, where the junction capacitance of the rectifier diode is to decrease the resonant current and output voltage in the circuit when compared with that in an ideal rectifier diode. This can be represented by a simplified series resonant equivalent circuit and a voltage transfer function versus the normalized operating frequency at varied values of the resonant capacitor. A low voltage to high voltage push-pull DC/DC resonant converter was used as a design example. The design procedure is based on the principle of the half bridge class-DE resonant rectifier, which ensures more accurate results. The proposed scheme provides a more systematic and feasible solution than the conventional resonant push-pull DC/DC converter analysis methodology. To increase circuit efficiency, the main switches and the rectifier diodes can be operated under the zero-voltage and zero-current switching conditions, respectively. In order to achieve this objective, the parameters of the DC/DC converter need to be designed properly. The details of the analysis and design of this DC/DC converter’s components are described. A prototype was constructed with a 62?88 kHz variable switching frequency, a 12 VDC input voltage, a 380 VDC output voltage, and a rated output power of 150 W. The validity of this approach was confirmed by simulation and experimental results.

Prospects for discovery and spin discrimination of dark matter in Higgs portal DM models and their extensions at 100 TeV pp collider

Dutta, Bhaskar,Kamon, Teruki,Ko, P.,Li, Jinmian Springer-Verlag 2018 European Physical Journal C Vol.78 No.7

Bi-Event Subtraction Technique at hadron colliders

Dutta, B.,Kamon, T.,Kolev, N.,Krislock, A. North-Holland Pub. Co 2011 Physics letters: B Vol.703 No.4

We propose the Bi-Event Subtraction Technique (BEST) as a method of modeling and subtracting large portions of the combinatoric background during reconstruction of particle decay chains at hadron colliders. The combinatoric background arises when it is impossible to know experimentally which observed particles come from the decay chain of interest. The background shape can be modeled by combining observed particles from different collision events and be subtracted away, greatly reducing the overall background. This idea has been demonstrated in various experiments in the past. We generalize it by showing how to apply BEST multiple times in a row to fully reconstruct a cascade decay. We show the power of BEST with two simulated examples of its application towards reconstruction of the top quark and a supersymmetric decay chain at the Large Hadron Collider.

매립지 침출수에 의해 오염된 토양의 동전기와 초음파에 의한 복원에 관한 연구

정하익,오인규,( Masashi Kamon ) 한국폐기물자원순환학회 2002 APLAS Vol.2002 No.2

매립지 침출수에 의한 지하수와 토양오염은 고형폐기물 매립에 있어 주요한 환경 문제다. 많은 나라는 불량매립지에 의해 제기되는 환경문제에 직면해 있다. 동전기 기술은 오염토양에서 중금속을 제거하는데 주로 적용되고, 초음파 기술은 유기물질을 제거하는데 주로 적용된다. 따라서 동전기와 초음파 기술의 조합은 오염토양의 중금속과 유기물질을 제거하는데 적용할 수 있다. 침출수에 의해 오염된 토양으로부터 오염물질을 제거하는데 있어 동전기와 초음파의 영향을 파악하기 위해서 특별히 제작한 장치를 이용하여 실험실 테스트를 실시하였다. 실험에 사용된 토양은 주문진의 미세 모래이고, 납(Pb)과 에틸렌글리콜(ethylene glycol)를 인위적으로 공급하여 오염물질로 사용하였다. 실험은 대조군 실험과 동전기, 초음파, 동전기+초음파 세정실험으로 크게 실시하였다. 동전기와 초음파 세정실험에서 투과성과 오염물질 제거효율이 증가하였다. 동전기+초음파 복원기술의 현장실행에 있어서의 기술적 타당성을 논하였다. Contamination of ground and groundwater by landfill leachate represents a major environmental concern associated with the landfilling of solid waste. Many countries are faced with environmental problems posed by old unregulated landfills. The electrokinetic technique is applied to remove mainly the heavy metal and the ultrasonic technique is applied to remove mainly organic substance in contaminated ground. Thus the combined electrokinetic and ultrasonic technique can be applied to remove heavy metal and organic substance in contaminated ground. The laboratory tests were conducted using specially designed and fabricated devices to determine the effect of ultrasonication and electrokinetics on contaminant removal from ground contaminated by landfill leachate. Test soil was Jumunjin fine sand and Pb and ethylene glycol were used as artificial contaminants. A series of laboratory experiments involving the simple, ultrasonic, electrokinetic, electrokinetic+ultrasonic flushing tests were carried out. An increase in permeability and contaminant removal rate was observed in electrokinetic and ultrasonic flushing tests. Some technical feasibility are discussed for in situ implementation of electrokinetic ultrasonic remediation technique.