• 설비공학논문집
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• 제29권7호
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• pp.360-365
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• 2017

Recently, development efforts of triple-effect absorption chiller have been increased in order to improve the efficiency of double-effect absorption chiller. However, triple-effect absorption chiller has some disadvantages, including high corrosion characteristic of LiBr solution at high temperature of $200^{\circ}C$. Moreover, it is necessary to develop new components for operation under high pressure of 2 bars even though COP is increased to 1.6 or 1.7. The objective of this study was to introduce a new system by combining double effect absorption chiller with single effect absorption chiller with multi-generators using bypass flow of LiBr dilute solution to $3^{rd}$ generator to overcome the disadvantages of triple-effect chiller and improve energy efficiency. Results indicate that the new absorption cycle had a much higher efficiency than double-effect chiller system, showing significant improvement when bypass solution flow rate of 25% was applied to the $3^{rd}$ generator using the main dilute solution of the absorber. The COP of the new chiller system was found to be 1.438, which was 21.7% higher than that (1.18) of the present double-effect system. The COP was decreased when solution by-pass rate to the $3^{rd}$ generator was increased. In addition, lower cooling water temperature caused higher COP. Therefore, the multi-generator system with by-pass solution might be an excellent chiller alternative to triple-effect absorption chiller with higher efficiency.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2007년도 제34회 KOSCO SYMPOSIUM 논문집
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• pp.13-18
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• 2007

When triple flames propagated in a diverging channel, the effects of fuel dilution on the lift-off characteristics of triple flames were investigated. A multi-slot burner was used to stabilize the lift-off flame especially at weak fuel concentration gradients. It was reported that there is a maximum propagation velocity at a critical concentration gradient in an open jet regardless of fuel dilution. The enhancement of a diffusion flame affected to increase the propagation velocity around critical concentration gradients. However, the influence of a confined channel on the structure of triple flames according to fuel dilution needs to be investigated compared with an open jet case. This study aimed to examine the effect of a confined channel on the structure and the propagation velocity of the triple flames according to fuel dilution. Lift-off height and propagation velocity of triple flames were investigated by employing three kinds of fuel compositions diluted by nitrogen (0%, 25%, 50% $N_2$), Fuel dilution reduced the propagation velocity of triple flame in a confined channel mainly due to the decrease of flame temperature in premixed branch. Despite the difference in fuel dilution, the propagation velocity has a maximum value at a specific fuel concentration gradient even though the critical concentration gradient increases with fuel dilution. And the critical concentration gradient in a confined channel is larger than that in an open jet due to enhancement of convective diffusion.

• 한국임상수의학회지
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• 제18권3호
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• pp.201-205
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• 2001

위내 Helicobacter 균속에 자연 감염된 개에서 삼중요법의 효과를 알아보기 위해 Helicobacter 균속에 자연 감염된 것으로 판명된 7두의 개를 대상으로 amoxicillin, metronidazole을 14일간 경구투여하였다. 삼중요법 실시에 따른 Helicobacter 균속 감염상태 변화를 평가하기 위해 투여 7일째, 14일째 그리고 투여 중지후 30일째의 위생검 조직에 대한 요소검사, Helicobacter 균속에 대한 중합효소 연쇄반응 검사와 함께 분변시료를 이용한 중합효소 연쇄반응 검사를 실시하였다. 삼중요법 14일째 위생검 조직의 요소검사에서는 7두중 6두가 음성이었으나 위생검조직과 분변시료의 중합효소 연쇄반응 검사에서는 각각 3두와 4두만이 음성이었다. 삼중요법 중지후 30일째 검사에서는 각 검사법이 모두 동일한 결과를 나타내었는데 7두중 3두에서 음성으로 나타났다. 이상의 결과를 바탕으로 위내 Helicobacter 균속에 자연 감염된 개에서 amoxicillin, metronidazole과 omeprazole을 이용한 삼중요법은 Helicobacter 균속 감염 정도를 낮추거나 때로는 완전 박멸할 수 있을 것으로 보여지기에 만성위염의 임상증상을 나타내는 개의 Helicobacter 균속 감염증에 적용할 수 있으리라 사료된다.

• International Journal of Air-Conditioning and Refrigeration
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• 제15권3호
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• pp.114-121
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• 2007

In this study, a modified reverse flow type, one of the triple effect absorption cycles, is studied for performance improvement. The cycle simulation is carried out by using EES(Engineering Equation Solver) program for the working fluid of $H_2O/LiBr$ solution. The split-ratios of solution flow rate, UA of each component, pumping mass flow rate of solution are considered as key parameters. The results show that the optimal SRH (split ratio of high side) and SRL (split ratio of low side) values are 0.596 and 0.521, respectively. Under these conditions, the COP is maximized to 2.1. The optimal pumping mass flow rate is selected as 3 kg/s and the corresponding UAEV A is 121 kW/K in the present system. The present simulation results are compared to the other literature results from Kaita's (2002) and Cho's (1998) triple effect absorption systems. The present system has a lower solution temperature and a higher COP than the Kaita's modified reverse flow, and it also gives a higher COP than the Cho's parallel flow by adjusting split ratios.

• 한국정보전자통신기술학회논문지
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• 제9권6호
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• pp.630-636
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• 2016

In this paper, a novel triple-mode cavity structure, designed for compactness and operating at 850 MHz, is analyzed. A cylindrical dielectric resonator is loaded into a metallic cylindrical cavity. Previous study has been focused on the analysis of the cylindrical dielectric resonator, but in this paper, the effect of the cylindrical metallic cavity has been analyzed. Enclosing the dielectric resonator inside the metallic cavity increases the resonant frequency of the dielectric resonator; however, this increases the quality factor and introduces the possibility of installing coupling screws. The principle of generation of triple-mode was investigated by parametric analysis. The generated triple-mode is TE011 mode and two orthogonally generated HEM121 modes. By adjusting the radius of the dielectric resonator, the height of the dielectric resonator, or the radius of the cylindrical metallic cavity, three modes could be coincided. However, the height of the metallic cavity keeps three modes separated. The mode characteristics of the proposed cavity are analyzed using a full-wave electromagnetic (EM) simulation. The proposed triple-mode cavity could be developed to triple-mode filter using a coupling screw, and the commercial application for the miniaturized filter below 1 GHz could be expected.

• 설비공학논문집
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• 제9권4호
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• pp.484-496
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• 1997

The fluid flow and heat transfer characteristics of conjugate forced and natural convection in the triple-glazed airflow window, where the outer air passes through a space contrived between the interior and exterior window panes, were studied numerically by a finite volume method for the elliptic form of the Navier-Stokes equations. The investigation focused on the influence of window geometry, ventilastion rate and solar energy on the temperature, velocity distribution and thermal performance of the airflow window. The comparison between the triple-glazed airflow window and the enclosed triple-glazed window was also made to evaluate the effect of buoyancy upon which the thermal performance of the window depended.

• Journal of Advanced Marine Engineering and Technology
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• 제22권6호
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• pp.782-791
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• 1998

This paper presents a computer simulation of five types of triple effect absorption cycles employ-ing the refrigerant absorbent combinations of NH3/LiNO3 low-pressure type NH3/LiNO3+H2O/LiBr binary two-stage type series flow cycle and two types of parallel flow cycle for H2O/LiBr. The absorption systems is investigated through cycle simulation to obtain the system characteristics with the cooling water inlet temperature approach temperature of absorber loss temperature of absorber and chilled water outlet temperature. The most important characteristic temperature of absorber and chilled water outlet temperature. The most important characteristic of NH3/LiNO3 low-pressure type and a NH3/LINO3+H2O/LiBr binary two-stage type is that it obtains a coefficient of performance higher than the sum of the performance coefficients of its part operating independently. As a result of this analysis the optimum designs and operating conditions were determined based on the operating conditions and the coefficient of performance.

• 대한설비공학회지:설비저널
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• 제33권3호
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• pp.43-49
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• 2004

This article reviews R＆D of triple effect cycle developed in Japan. Most of the refrigeration and heat pump technologies are dominated by vapor compressor system. The vapor compressor system, however, is highly concerned with the environmental regulations , as most of the vapor compressor technologies are using CFCs or HCFCs which are known as ozone depleting and global warming gases. As a consequence, refrigeration technologists are trying to invent or to develop an alternative to vapor compressor refrigeration devices. Thermally driven, absorption technology is one of the possible alternatives. At the moment, absorption cycle is most promising technology The paper summarizes briefly the current research and development in advanced technologies of triple effect absorption chiller-heater in Japan.(omitted)

• Asian Pacific Journal of Cancer Prevention
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• 제16권12호
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• pp.4885-4890
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• 2015

Background: Helicobacter pylori plays an important role in gastric cancer and typical eradication regimens are no longer effective in many countries, including Thailand. The aim of our study was to compare the effect of Lactobacillus delbrueckii and Streptococcus thermophillus on tailored triple therapy for Helicobacter pylori eradication. Materials and Methods: This prospective single-center study was conducted in Thailand. Helicobacter pylori associated gastritis patients were randomized to 2 groups: group 1 (n=100) was tailored triple therapy with placebo (esomeprazole 20 mg bid, clarithromycin 500 mg bid or metronidazole 400 mg tid if clarithromycin resistance and amoxicillin 1000 mg bid), and group 2 was tailored triple therapy plus pretreatment with probiotic containing yogurt. Successful eradication was defined as both negative histology and negative rapid urease test at four weeks after treatment. Results: A total of 200 infected patients were enrolled. PP analysis involved 194 patients: 96 in the tailored triple therapy with placebo group (group 1) and 98 the in tailored triple therapy plus pretreatment with probiotic containing yogurt group (group 2). Successful eradication was observed in 170 (87.6%) patients; by PP analysis, the eradication rate was significantly higher in group 2 (P = 0.04, 95%CI; 0.02-0.13) than in group 1. ITT analysis also showed that the value was significantly higher in the tailored triple threapy plus pretreatment with probiotic containing yogurt group (group 2) (89/100; 89%) than in the tailored triple therapy with placebo group (group 1) (P= 0.01, 95%CI; 0.04-0.15). In terms of adverse events, there was no significant difference between the two groups. Conclusions: Pretreatment with probiotic containing yogurt can improve Helicobacter pylori eradication rates with tailored triple therapy. Adding probiotics does not reduce adverse effects of the medication.

• 한국경제지리학회지
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• 제17권1호
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• pp.69-85
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• 2014

본 연구의 목적은 두 종류의 서로 다른 트리플 헬릭스 모델(대학주도형 vs. 제3섹터형)이 기업혁신에 미치는 영향을 밝히는 데 있다. 특히 사회적 자본으로서의 신뢰가 두 종류의 트리플 헬릭스 상호작용과 기업혁신 사이의 관계에 있어 조절효과를 보이는 지에 주안점을 두고 있다. 우리나라에서는 정부부처(교과부 vs. 지식경제부: <교육부 vs. 미래창조과학부>)를 중심으로 크게 두 가지 방식의 트리플 헬릭스 상호작용이 진행되어 왔다. 하나는 기업가적 대학이 중심적인 역할을 하는 대학주도형 전통적인 트리플 헬릭스 상호작용이며, 또 다른 하나는 테크노파크와 같은 제3섹터형 기관이 트리플 헬릭스 상호작용을 수행하는 제3섹터 주도형 방식이다. 본 연구는 대구 경북 지역에 위치한 231개 기업으로부터 수집한 자료를 바탕으로 하고 있다. 분석 결과, 첫째 제3섹터형 기관의 지원을 통한 트리플 헬릭스 상호작용은 기업혁신에 정(+)의 영향을 미치는 것으로 나타났다. 반면 대학주도형 트리플 헬릭스 상호작용은 기업혁신에 유의미한 영향을 미치지 못했다. 둘째, 제3섹터형 기관의 지원은 전통적인 트리플 헬릭스 상호작용보다 기업혁신에 더 큰 정(+)의 영향을 미치는 것으로 나타났다. 셋째, 신뢰는 두 종류의 트리플 헬릭스 상호작용에 있어서 기업혁신에 대한 정(+)의 조절효과를 보여주었다. 결론에서는 연구의 시사점과 연구의 한계점, 향후 연구방향 등이 제시되었다.