Earticle

본 논문에서는 물류용기의 유통 환경 적합성, 충격 시험 을 통한 완충 특성, 온도 유지 성능 평가를 통해 재활용 소재의 물류용기 적용 가능성을 검토하였다. 또한, 새벽 배 송 시장에서 유통 중인 재사용 물류용기와 비교 시험을 수 행하였다. 유통환경 적합성 평가는 KS T 5055에 근거하여 압축, 낙하, 수직 랜덤 진동 시험을 수행하였으며, 압축 시험의 경 우 KS T ISO 12048 및 KS T ISO 2234를 참고하여 적 재 시험으로 수행하였다. 1.5의 적재 계수를 적용해 도출된 하중으로 압축 시험을 수행한 결과, 두 종류의 물류용기 모 두 하중을 견디지 못하고 구조가 무너져 내용물인 물과 아 이스팩이 파손되었다. 반면, 1.0의 안전 계수를 적용해 계 산된 하중을 물류용기에 가했을 때는 물류용기의 형태가 변 형되지 않고 그대로 유지되어, 두 물류용기 모두 새벽 배송 에 적합한 하중을 견딜 수 있음을 적재 실험을 통해 확인 하였다. 낙하 시험과 수직 랜덤 진동 시험에서는 시험 후 두 물류용기 모두 내·외부 및 내용물에 특이사항이 없었기 때문에, 유통 적합성에 문제가 없음을 알 수 있었다. 충격 시험은 수직 방향으로 수행되어 물류용기의 완충 특 성을 평가하였다. 제작용기는 상자 단독으로 진행한 충격 시험에 비해 충격 가속도와 충격량이 감소되어 완충 특성 이 향상된 것으로 확인되었다. 그러나 유통 중인 재사용 물 류용기는 충격 가속도와 충격량이 가장 낮게 측정되어 제 작용기보다 우수한 완충 특성을 보였다. 이는 재사용 물류 용기의 내장재 두께가 완충 성능에 영향을 미친 것으로 판 단된다. 새벽 배송의 주요 제품군은 신선 식품으로, 온도 유지 특 성이 매우 중요하다. 온도 유지 평가는 ISTA 7E를 활용하 여 수행했으며, 모든 물류용기에서 10시간 이상 10oC 이하 의 내부 온도가 유지되었기 때문에 신선 식품의 새벽 배송 을 위한 단열성이 확보된 것을 확인했다. 이처럼 재활용 소 재를 적용한 물류용기가 모든 시험에서 성공적인 시험 결 과를 보였으며, 기존에 유통 중인 재사용 물류용기와 유사한 성능을 보였기 때문에 새벽 배송 용기로 적용이 가능한 것으로 판단된다. 기존의 새벽 배송 물류용기는 재활용이 어려운 소재로 구성되어 있지만, 재활용 소재를 적용한다면 재활용 소재의 활용과 플라스틱 폐기물량 감소로 환경에 긍 정적인 효과를 기대할 수 있다.

Delivery services in Korea are available in a number of alternatives, including one-day, next-day, and earlymorning delivery. Particularly, the market for early-morning delivery is expanding due to the preference for customer convenience, the demand for contactless shopping, and the increase in single-person households. For fresh food delivery, consumers widely use early-morning delivery services, with EPS (Expanded Polystyrene) boxes commonly used. While EPS boxes are cost-effective and have excellent insulation properties, the introduction of reusable containers is being implemented to replace them due to environmental pollution issues. This paper evaluates the performance of a reusable logistics container made from recycled materials. The container carried out tests for distribution environment suitability, impact resistance, and temperature maintenance performance. The results showed that the container passed all tests successfully, confirming that it has the appropriate performance for fresh food delivery via early-morning delivery. Additionally, it demonstrated similar performance to reusable logistics containers currently in use, indicating its applicability in the market.

This paper presents a torque distribution algorithm for improving the stability and mobility of a wall-climbing robot platform. During ascent, the pitch moment caused by the payload or external disturbances separates the robot's triangular tracks from the wall, significantly deteriorating its stability. Moreover, the reaction forces stemming from the increase in the pulling force may degrade the robot's mobility. Thus, it is very important to minimize the reaction forces acting on the triangular tracks, as well as the fluctuations in the pulling force, during the climb. Through dynamic modeling of the proposed robot platform, we demonstrated the dependence of the robot's stability and mobility on the torque distribution of the triangular tracks. Extensive simulations using different climbing speeds were used to significantly improve the stability and mobility of the proposed robot platform.

[서론] 본 연구는 성인 남녀의 일상생활에서 다양한 습관으로 인해 발생되는 자세 변형 중 거북목자세가 경도 이상인 대상자를 선별하여 동적안정성운동과 능동적신장운동을 통해 거북목 증후군의 자세 변화에 따른 정적 및 동적압력분포의 변화를 규명하여 임상에 유익한 정보를 제공하고자 한다. [방법] 본 연구의 대상은 부산광역시 소재 K대학에서 뉴욕 주 자세평가 기준표를 활용하여 거북목자세 정도가 경도변형 이상인 자에 대하여 연구에 자발적으로 참여하고자 동의한 남, 여 42명을 대상으로 족저압력분포검사, 자세변화 검사를 측정한 후 동적안정성운동군, 능동적신장운동군, 대조군으로 각 군을 배치하고 각 군마다 1주당 3회, 4주간 각 군마다 중재방법에 맞게 치료 전, 치료 2주 후, 치료 4주 후에 족저압력분포검사, 자세변화 검사를 측정하였다. 뉴욕주 메모리얼 솔론 케트링 암센터(New York state Memorial Sloan-Kettering Cancer center)와 NISMAT(Nicholas Institute of spotrs Medicine and Athletic Trauma)에서 권장하고 있는 신장운동프로그램을 현실에 맞게 개선하여 능동적 신장운동을 실시하였다. 본 연구는 수집된 자료를 SPSS(version 18.0)통계 프로그램을 이용하여 분석하였다. [결과] 치료기간에 따른 압력분포 분석을 통한 좌, 우 족부의 전후 정적압력분포변화를 비교한 결과 동적안정성운동군과 능동적신장운동군에서 전후 족부의 압력분포가 감소하는 것으로 보아 균형능력이 향상되게 나타났으며, 치료 전·후에 따른 자세 변화를 비교한 결과 각 군간 치료 전·후의 자세 변화는 큰 차이가 없는 것으로 나타났으나, 각 군별 치료 전·후에 따른 자세 비교 결과에서는 감소하는 것으로 나타났다(p<.05). [결론]본 연구에서 목 주변 불균형의 결과로 초래된 거북목 자세에 대하여 실험한 결과를 보면 동적안정성운동과 능동적신장운동의 적용이 대조군에 비해 거북목 자세의 변화가 감소하는 것을 확인할 수가 있었고, 자세 변화와 관련하여 족저압력분포의 균형능력 또한 향상되는 것을 알 수 있었다.

[INTRODUCTION] The purpose of this study was to evaluate the influence of active stretching and dynamic stability exercises on Turtle neck posture. [METHOD] In order to judge the turtle neck posture, 42 persons with inclination disorder who were selected based on the New York state posture evaluation table were grouped randomly into the group of dynamic stability exercises, the group of active stretching exercise, and the control group, and the exercise program were applied to each intervention group of exercise 3 times a week for 4 weeks and nothing was applied to the control group. As the methods of measurement, the Balance analysis and postural changes analysis were conducted before exercising, pre treatment, after 2 weeks, after 4 weeks and the evaluation of posture was measured before exercising and after finishing, and the data collected from these procedures were analyzed. [RESULT] The comparison of the variation due to the duration of fore and rear foot static pressure distribution the analysis on the decreased due to the exercise duration(p<.05). The comparison of the variation due to the duration of fore and rear foot dynamic pressure distribution the analysis on the decreased due to the exercise duration(p<.05). [CONCLUSION] The seeking for the posture change in pre-post exercise showed the results of no effective difference between the three groups.

(t); t \geq 0} on R^1$ satisfying the following stochastic differential equation.

In this study, the effects of the double emulsification method on the rheological properties, particle size, and stability of low-fat mayonnaise were studied. Different water-phase-to-oil ratios (2:8 and 4:6) of primary emulsions and different stabilizer types (sodium caseinate, xanthan gum, and lecithin-whey protein concentrate) were used to produce double-emulsified mayonnaise. As a control sample, mayonnaise was prepared conventionally. Sodium caseinate was found to be the most efficient stabilizer. In the presence of sodium caseinate, the stability and apparent viscosity of double-emulsified mayonnaise increased but their particle sizes decreased. It was found that flow behavior of double-emulsified and conventionally prepared mayonnaise could be described by the power law model. The double-emulsified mayonnaise samples were not different from the control samples in terms of stability and particle size. In addition, using the double emulsion method, it was possible to reduce the oil content of mayonnaise to 36.6%.

Carbon Nanotubes (CNTs) are considered as an ideal reinforcement to improve the properties of the Aluminium (Al) matrix composites. Even though a significant improvement in mechanical, thermal and electrical properties obtained in Al-CNT composites, there are still several challenges to get uniform dispersion in the matrix and interfacial bonding between CNTs and Al matrix. The objective of the present work is to study the influence of ball milling time on structural stability and distribution of CNTs in Al matrix. The fabricated composite powders morphology like grain size and CNT structural quality were analyzed using Scanning Electron Microscope (SEM), X-ray diffraction (XRD) and Raman spectroscope. It was found that the 6 hrs of ball milling is an effective way to achieve homogeneous distribution of CNTs in Al matrix. The highest hardness value of 77.4 Hv was obtained at 6 hrs ball milling time and subsequently the hardness was reduced to 46.2 Hv at 12 hrs. The reduced hardness of Al-CNT composites may be attributed to lower structural qualities of CNTs with longer milling time. This is evident from the ID/IG values of 0.92 and 1.04 for the 6 hrs and 12 hrs ball milled composites respectively

RSK2, also known as RPS6KA3 (ribosomal protein S6 kinase, 90 kDa, polypeptide 3), is a downstream kinase of the mitogenactivated protein kinase (MAPK) pathway, which is important in regulating survival, transcription, growth and proliferation. However, its biological role in mitotic progression is not well understood. In this study, we examined the potential involvement of RSK2 in the regulation of mitotic progression. Interestingly, depletion of RSK2, but not RSK1, caused the accumulation of mitotic cells. Time-lapse analysis revealed that mitotic duration, particularly the duration for metaphase-to-anaphase transition was prolonged in RSK2-depleted cells, suggesting activation of spindle assembly checkpoint (SAC). Indeed, more BubR1 (Bub1-related kinase) was present on metaphase plate kinetochores in RSK2-depleted cells, and depletion of BubR1 abolished the mitotic accumulation caused by RSK2 depletion, confirming BubR1-dependent SAC activation. Along with the shortening of inter-kinetochore distance, these data suggested that weakening of the tension across sister kinetochores by RSK2 depletion led to the activation of SAC. To test this, we analyzed the RSK2 effects on the stability of kinetochore?microtubule interactions, and found that RSK2-depleted cells formed less kinetochore?microtubule fibers. Moreover, RSK2 depletion resulted in the decrease of basal level of microtubule as well as an irregular distribution of mitotic spindles, which might lead to observed several mitotic progression defects such as increase in unaligned chromosomes, defects in chromosome congression and a decrease in pole-topole distance in these cells. Taken together, our data reveal that RSK2 affects mitotic progression by regulating the distribution, basal level and the stability of mitotic spindles.

Ga-based semiconductor nanowires (GaN, GaP) were synthesized by the reaction of Ga metal and GaN/GaP powder with a $NH_3/Ar$ gas using thermal chemical vapor deposition. The field emission and emission stability under oxygen and argon environments were investigated. Field emission energy distributions of electrons from these nanowires revealed that field emission mechanism of the semiconductor nanowires were different from carbon nanotubes.

Influences of the spatial distribution of resource patches on the host-parasitoid system (brown rice patch - rice weevil - Anisopteromalus calandrae) dynamics and stability in patchy environment were studied with a biological model system. When the 40 empty patches, the host population in creased logistically and then fluctuated at an equilibrium level about 5,000. However, when the resource patches were randomly distributed, the host population showed a cyclical fluctuations in the range from 532 to 7089 with significant delayed density-dependence. Distribution of resource patches affected the distribution of hosts among resource patches, which could be a reason for the different features of population dynamics in the two system. In both resource patch distribution systems, the interactions between host and damping. The equilibrium level in each system was far below than that in the system without parasitoid, suggesting that the parasitoid did regulate the host population. However, overall mortality of host density-dependent in the random system. Therefore, the regulation seemed due not to overall host density-dependent parasitism, but rather to the indirect effect of the parasitoid leading the host population to be highly aggregating to some resource patches, which, in turn, resulted in stronger intraspecific competition in the contagious resource patch system, whereas it was parasitism in the random patch system. The persistence and stability of host-parasitoid population interaction, the role of parasitoid in the interaction and the resulting equilibrium level were discussed with reference to the resource patch distribution.

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease that is frequently linked to microtubule abnormalities and mitochondrial trafficking defects. Whole exome sequencing (WES) of patient-parent trios has proven to be an efficient strategy for identifying rare de novo genetic variants responsible for sporadic ALS (sALS). Using a trio-WES approach, we identified a de novo RAPGEF2 variant (c.4069G>A, p.E1357K) in a patient with early-onset sALS. To assess the pathogenic effects of this variant, we have used patient-derived skin fibroblasts and motor neuron-specific overexpression of the RAPGEF2-E1357K mutant protein in Drosophila. Patient fibroblasts display reduced microtubule stability and defective microtubule network morphology. The intracellular distribution, ultrastructure, and function of mitochondria are also impaired in patient cells. Overexpression of the RAPGEF2 mutant in Drosophila motor neurons reduces the stability of axonal microtubules and disrupts the distribution of mitochondria to distal axons and neuromuscular junction (NMJ) synapses. We also show that the recruitment of the pro-apoptotic protein BCL2- associated X (BAX) to mitochondria is significantly increased in patient fibroblasts compared with control cells. Finally, increasing microtubule stability through pharmacological inhibition of histone deacetylase 6 (HDAC6) rescues defects in the intracellular distribution of mitochondria and BAX. Overall, our data suggest that the RAPGEF2 variant identified in this study can drive ALSrelated pathogenic effects through microtubule dysregulation.

본 연구에서는 Han and Lee(2012)에서 논의되었던 ‘최적 유동성(optimal liquidity)’의 개념을 재정의하고 확장하였다. 이를 위하여 Levhari and Patinkin(1968)과 Yoo and Pyo(1986)를 따라 가계와 생산자의 유동성을 상이한 것으로 구별하였다. Han and Lee(2012)는 Walsh(2012)의 ‘money-in-utility’ 모형을 변형하여 유동성과 소비 간의 관계를 도출하였는데, 본 연구는 이를 ‘money-in-utility-and-production’ 모형으로 확장하였다. 즉 유동성이 가계의 효용함수뿐만 아니라 생산함수의 투입요소로 포함되는 DSGE 모형을 고안하여 충격반응분석을 단행하였다. 그 결과 TFP 증가에 따른 대부분의 주요변수들의 반응은 Bhattacharjee and Thoenissen(2007)의 연구와 일치하였다. 반면 정책 이자율은 역-U자형(hump-shaped) 반응을 보이는 것으로 나타났으며, 이는 통화량의 증가를 반영한 ‘cash-in-advance’ 모형의 결과와 유사하다. 또한 통화량의 공급 증가는 기업의 유동성 비중을 감소시키는 일종의 구축효과(crowding out effect)가 있는 것으로 나타났다. 본 모형의 정책적 함의는 최적 유동성의 절대량뿐 아니라 유동성의 총량이 소비자와 기업들에 어떻게 분배되었는가 하는 문제 역시 경제성장과 안정성을 결정하는 데 있어서 중요한 요소라는 것이다. 이를 검증하기 위해 패널 회귀분석을 단행하였으며, 생산자 부문의 유동성 소유 비중이 높을수록 GDP 성장뿐 아니라 GDP 성장의 안정성에도 기여한다는 결과를 도출하였다.

This research paper intends to redefine and extend the concept of ‘optimal li-quidity’ discussed in Han and Lee (2012). For this purpose, we have distinguished between liquidity held by households and liquidity held by firms following Levhari and Patinkin (1968) and Yoo and Pyo (1986). Han and Lee (2012) have revised the ‘money-in-utility’ model by Walsh (2012) and derived the relationship between liquidity and consumption. In the present paper, we have extended Han and Lee (2012) to a ‘money-in-utility-and-production’ model. We have specified a DSGE model in which liquidity serves for both household utility and production input and have conducted the impulse-response analysis. The impulse-responses of most of important variables from the shock of TFP increase are consistent with the results of Bhattacharjee and Thoenissen (2007). On the other hand, the policy interest rate shows a hump-shaped impulse-response, which is consistent with the impulse response of monetary expansion in the cash-in-advance model. In addition, the increase in money supply has produced a kind of crowding-out effect reducing the share of liquidity held by firms. The main policy implication of our model is that not only the absolute level of optimal liquidity but also the relative distribution of the liquidity between households and firms are important determinant for economic growth and stability. In order to validate this proposi-tion, we have conducted a panel regression analysis and have empirically verified the proposition that the relatively higher share of liquidity held by firms would contribute to both GDP growth and its stability.

본 논문에서는 균일 모멘트 하중을 받는 박판 아치의 탄성 좌굴에 관한 연구를 수행하였다. 초기 곡률을 고려한 비선형 변형률-변위 관계식을 전체 포텐셜 에너지 방정식의 이차 변분에 대입하여 초기 곡률 효과를 포함하는 에너지 방정식을 유도하였다. 휨 모멘트에 의한 단면 내 법선 변형률이 선형으로 분포한다는 초기 곡률 효과에 대한 가정사항을 유도과정에 일관되게 적용하였다. 균일 모멘트 하중을 받는 아치의 휨-비틀림 좌굴하중에 관한 제차해를 제시하고 타 연구자의 결과와 비교하였다.

This paper is concerned with the elastic buckling of thin-walled arches that are subjected to uniform bending. Nonlinear strain-displacement relations with the initial curvature are substituted into the second variation of the total potential energy to obtain the energy equation including initial curvature effects. The approximation for initial curvature effects that the bending normal strain distribution is linear across the cross section is applied consistently in the derivation process. The closed form solution is obtained for flexural-torsional buckling of arches under uniform bending and, it is compared with the previous theoretical results.

Nonlinear vibration and instability of cylindrical shell conveying fluid-nanoparticles mixture flow are studied in this article. The surrounding elastic medium is modeled by Pasternak foundation. Mixture rule is used for obtaining the effective viscosity and density of the fluid-nanoparticles mixture flow. The material properties of the elastic medium and cylindrical shell are assumed temperature-dependent. Employing first order shear deformation theory (FSDT), the motion equations are derived using energy method and Hamilton's principal. Differential quadrature method (DQM) is used for obtaining the frequency and critical fluid velocity. The effects of different parameters such as volume percent of nanoparticles, boundary conditions, geometrical parameters of cylindrical shell, temperature change, elastic foundation and fluid velocity are shown on the frequency and critical fluid velocity of the structure. Results show that with increasing volume percent of nanoparticles in the fluid, the frequency and critical fluid velocity will be increases.

This paper deals with the dynamic stability of embedded functionally graded (FG)-carbon nanotubes (CNTs)-reinforced micro cylindrical shells. The structure is subjected to harmonic non-uniform temperature distribution and 2D magnetic field. The CNT reinforcement is either uniformly distributed or FG along the thickness direction where the effective properties of nano-composite structure are estimated through Mixture low. The viscoelastic properties of structure are captured based on the Kelvin-Voigt theory. The surrounding viscoelastic medium is considered nonhomogeneous with the spring, orthotropic shear and damper constants. The material properties of cylindrical shell and the viscoelastic medium constants are assumed temperature-dependent. The first order shear deformation theory (FSDT) or Mindlin theory in conjunction with Hamilton's principle is utilized for deriving the motion equations where the size effects are considered based on Eringen's nonlocal theory. Based on differential quadrature (DQ) and Bolotin methods, the dynamic instability region (DIR) of structure is obtained for different boundary conditions. The effects of different parameters such as volume percent and distribution type of CNTs, mode number, viscoelastic medium type, temperature, boundary conditions, magnetic field, nonlocal parameter and structural damping constant are shown on the DIR of system. Numerical results indicate that the FGX distribution of CNTs is better than other considered cases. In addition, considering structural damping of system reduces the resonance frequency.

The Active Superconducting Current Controller (ASCC) is a new type of Superconducting Fault Current Limiters (SFCL) which can limit the fault current in different modes. It also has the particular abilities of compensating active and reactive powers for electrical networks. In this paper, it is confirmed that the performance of ASCC in different operating modes introduces a limiting impedance in series with the network which can even degrade the transient stability and the operation of the Over-Current Relays (OCR) employed in a power system. In addition, the model of a three-phase ASCC is simulated, and the effect of descriptive modes on the current limiting level is investigated. For the transient stability analysis, a single machine-infinite bus system is tested, and the effect of operation modes is studied based on an equal area criterion obtaining the critical time and the critical angle. Modifying the setting parameters of OCR such as time dial and pick-up current, the protective coordination is also studied in different operating modes.

본 논문에서는 물류용기의 유통 환경 적합성, 충격 시험을 통한 완충 특성, 온도 유지 성능 평가를 통해 재활용 소재의 물류용기 적용 가능성을 검토하였다. 또한, 새벽 배송 시장에서 유통 중인 재사용 물류용기와 비교 시험을 수행하였다. 유통환경 적합성 평가는 KS T 5055에 근거하여 압축, 낙하, 수직 랜덤 진동 시험을 수행하였으며, 압축 시험의 경우 KS T ISO 12048 및 KS T ISO 2234를 참고하여 적재 시험으로 수행하였다. 1.5의 적재 계수를 적용해 도출된 하중으로 압축 시험을 수행한 결과, 두 종류의 물류용기 모두 하중을 견디지 못하고 구조가 무너져 내용물인 물과 아이스팩이 파손되었다. 반면, 1.0의 안전 계수를 적용해 계산된 하중을 물류용기에 가했을 때는 물류용기의 형태가 변형되지 않고 그대로 유지되어, 두 물류용기 모두 새벽 배송에 적합한 하중을 견딜 수 있음을 적재 실험을 통해 확인하였다. 낙하 시험과 수직 랜덤 진동 시험에서는 시험 후 두 물류용기 모두 내·외부 및 내용물에 특이사항이 없었기 때문에, 유통 적합성에 문제가 없음을 알 수 있었다. 충격 시험은 수직 방향으로 수행되어 물류용기의 완충 특성을 평가하였다. 제작용기는 상자 단독으로 진행한 충격 시험에 비해 충격 가속도와 충격량이 감소되어 완충 특성이 향상된 것으로 확인되었다. 그러나 유통 중인 재사용 물류용기는 충격 가속도와 충격량이 가장 낮게 측정되어 제작용기보다 우수한 완충 특성을 보였다. 이는 재사용 물류용기의 내장재 두께가 완충 성능에 영향을 미친 것으로 판단된다. 새벽 배송의 주요 제품군은 신선 식품으로, 온도 유지 특성이 매우 중요하다. 온도 유지 평가는 ISTA 7E를 활용하여 수행했으며, 모든 물류용기에서 10시간 이상 10℃ 이하의 내부 온도가 유지되었기 때문에 신선 식품의 새벽 배송을 위한 단열성이 확보된 것을 확인했다. 이처럼 재활용 소재를 적용한 물류용기가 모든 시험에서 성공적인 시험 결과를 보였으며, 기존에 유통 중인 재사용 물류용기와 유사한 성능을 보였기 때문에 새벽 배송 용기로 적용이 가능한 것으로 판단된다. 기존의 새벽 배송 물류용기는 재활용이 어려운 소재로 구성되어 있지만, 재활용 소재를 적용한다면 재활용 소재의 활용과 플라스틱 폐기물량 감소로 환경에 긍정적인 효과를 기대할 수 있다.

Delivery services in Korea are available in a number of alternatives, including one-day, next-day, and early-morning delivery. Particularly, the market for early-morning delivery is expanding due to the preference for customer convenience, the demand for contactless shopping, and the increase in single-person households. For fresh food delivery, consumers widely use early-morning delivery services, with EPS (Expanded Polystyrene) boxes commonly used. While EPS boxes are cost-effective and have excellent insulation properties, the introduction of reusable containers is being implemented to replace them due to environmental pollution issues. This paper evaluates the performance of a reusable logistics container made from recycled materials. The container carried out tests for distribution environment suitability, impact resistance, and temperature maintenance performance. The results showed that the container passed all tests successfully, confirming that it has the appropriate performance for fresh food delivery via early-morning delivery. Additionally, it demonstrated similar performance to reusable logistics containers currently in use, indicating its applicability in the market.

This study investigates the distribution stability of binary nanofluids where binary mixtures such as $NH_3/H_2O$ and $H_2O/LiBr$ solution are used as a base fluid. When a little amount of certain nanosized particles is added into a basefluid, the thermal conductivity of that mixture increases greatly. Such mixtures are named 'nanofluids' where nano-particles should be distributed stably and uniformly so the distribution stability of nanoparticles in nanofluids is one of the most important factors for nanofluid application. Therefore, binary nanofluids in which binary mixtures are applied as the basefluids are considered as working fluids. The kind and the concentration of nanoparticles, and the concentration of ammonia are considered as the key parameters. The objectives of this paper are to visualize the dispersed status of particles in binary nanofluids and to find the effect of key parameters on the distribution stability in the ammonia absorption system.