• 한국항만경제학회지
• /
• 제30권4호
• /
• pp.255-273
• /
• 2014

본 연구는 인천내항, 인천북항, 평택항 간 물동량의 영향관계 분석을 위해 그랜저 인과관계 검정, 벡터자기회귀모형을 사용하였다. 그랜저 인과관계 검정결과 인천내항 물동량은 평택항 물동량의 원인변수임을, 평택항 물동량은 인천북항 물동량의 원인변수임을 확인하였다. 한편, 벡터자기회귀모형을 적용함으로써 얻은 충격반응함수를 통해 인천내항 물동량은 인천북항 물동량, 평택항 물동량과는 음의 관계가 존재함을 알 수 있었고, 인천북항 물동량과 평택항 물동량 간에는 양의 관계가 존재함을 알게 되었다. 또한, 벡터자기회귀모형을 적용함으로써 얻게 된 예측오차 분산분해를 통해 인천내항 물동량의 예측오차는 시간의 경과에 따라 인천북항 물동량의 변동에 의해 설명되는 비중이 커짐을, 평택항 물동량의 예측오차는 시간의 경과에 따라 인천내항 물동량의 변동에 의해 설명되는 비중이 커짐을 알게 되었다. 연구결과 평택항 물동량의 변동이 인천항 전체에 부정적인 영향을 미치는 것은 아니며, 부속 항만에 따라 영향을 달리 받을 수 있음을 알게 되었다. 이는 인천항, 평택항을 운영하는 항만운영 당국간 경쟁과 협력이 모두 가능하다는 것을 보여주며, 상호 협력할 부분과 경쟁할 부분을 명확히 한다면 양항이 함께 발전할 수 있을 것임을 의미한다.

• Steel and Composite Structures
• /
• 제48권4호
• /
• pp.419-428
• /
• 2023

In this paper, dynamic and static bending of ball modelled by nanocomposite microbeam by nanoparticles seeing agglomeration is presented. The structural damping is considered by Kelvin-Voigt model. The agglomeration effects are assumed using Mori-Tanaka model. The football ball is modeled by third order shear deformation theory (TSDT). The motion equations are derived by principle of Hamilton's and energy method assuming size effects on the basis of Eringen theory. Using differential quadrature method (DQM) and Newmark method, the static and dynamic deflections of the structure are obtained. The effects of agglomeration and CNTs volume percent, damping of structure, nonlocal parameter, length and thickness of micro-beam are presented on the static and dynamic deflections of the nanocomposite structure. Results show that with increasing CNTs volume percent, the maximum dimensionless dynamic deflection is reduced about 17%. In addition, assuming CNTs agglomeration increases the dimensionless dynamic deflection about 14%. It is also found that with increasing the CNTs volume percent from 0 to 0.15, the static deflection is decreased about 3 times due to the enhance in the stiffness of the structure. In addition, with enhancing the nonlocal parameters, the dynamic deflection is increased about 3.1 times.

• 한국수소및신에너지학회논문집
• /
• 제28권5호
• /
• pp.459-464
• /
• 2017

The volume expansions of $Ti_{0.95}Zr_{0.05}V_{0.4}Mn_{1.45}Fe_{0.1}Cr_{0.05}$ alloy during hydrogenation with various conditions have been investigated. The theoretical volume expansion measured with XRD for this alloy with hydrogenation was 21%. The apparent volume expansion of this alloy ingot with hydrogenation was composed of two effects. One is a hydrogenation and the other is a pulverization. The apparent volume of free alloy powder was 1.8 times greater than that of an ingot, implying the pulverization effect on the apparent volume expansion is 80%. The apparent volume expansion of the alloy ingot with hydrogenation under a unconstrained condition was about 80 (${\pm}15$)%, much smaller than that of free alloy powder which expected as 118%. In addition, The apparent volume expansion of the alloy ingot with hydrogenation under a constrained condition(Al container) was about 50%, much smaller than that of the unconsrained. This reduced apparent volume expansion of the alloy ingot could be attributed to an arrangement of alloy powder keeping its original shape of the ingot even after hydrogenation.

• 대한한의학회지
• /
• 제38권4호
• /
• pp.41-54
• /
• 2017

Objectives: The purpose of this study is to investigate the effects of Sa-am acupuncture with Pericardium jung-gyuck (SA-acu-PC) and Triple Energizer jung-gyuck (SA-acu-TE) on the radial pulse in healthy human subjects. Methods: Sixty healthy subjects participated in this study and divided into three groups randomly: Control group(C), Pericardium jung-gyuck group(PC), Triple Energizer jung-gyuck group(TE). Radial pulse was measured by 3 dimensional pulse imaging system (DMP-3000) before, right after, 30 minutes after, and 60 minutes after acupuncture. Results: 1. The changes observed in periodic parameters are considered as the common effects of both SA-acu-TE and SA-acu-PC. SA-acu-TE was more effective than SA-acu-PC in these effects. 2. The effects of SA-acu-PC appeared in the pulse amplitude, pulse area, and pulse power volume mainly at the left chon position, and 3. The effects of SA-acu-TE appeared in the radial augmentation index and main peak angle mainly at the right gwan position. Conclusions: The effects of SA-acu-PC and SA-acu-TE can be observed in the radial pulse. The increases in pulse amplitude, pulse area, and pulse power volume at the left chon may imply the effects of SA-acu-PC. And the decrease in the pulse power volume, the increases in radial augmentation index and main peak angle may imply the effects of SA-acu-TE.

• 한국안전학회지
• /
• 제15권3호
• /
• pp.52-56
• /
• 2000

The finite control volume method was utilized to investigate the effects of flow through openings on convection in an enclosure. Flow patterns and temperature distribution were compared for non-dimensional inflow velocity U=20, 40, 60 at Ra=$10^4$ and $5\times10^4$, respectively. The inflow velocity influenced temperature distribution in the enclosure significantly and lowered temperature on the top wall. The flow through openings forced the position of the highest temperature on the top wall to move toward the outflow opening.

• 무역학회지
• /
• 제47권4호
• /
• pp.35-52
• /
• 2022

Air transport is at the core of global economic growth. There is a close relationship between the flow of regional elements and the growth of the regional economy. It is easy to misestimate the impact of airports on the regional economy without considering spatial spillover effects. This study attempted to establish an asymmetric economic geographical weight matrix by applying the Spatial Durbin Model with cargo volume and passenger numbers as indicators. The influence of spillover effects on the regional economy, including direct spillover effects and indirect spillover effects are studied. The results revealed that passenger numbers and cargo volume have significant positive spillover effects on the regional economy. The driving effect of the airport on the regional economy was considered from a wider space scope. This study contributes to the scientific evaluation of the aviation economy.

• 한국환경보건학회지
• /
• 제29권2호
• /
• pp.56-61
• /
• 2003

This study was performed to examine the effects of chaff as a bulking material on temperature, pH, weight and volume reduction and salinity in aerobic composting of food wastes. Volume ratios of food wastes to chaff in reactor of Control, Ch-1. Ch-2, Ch-3 and Ch-4 were 4:0, 4:1, 4:2, 4:3 and 4:4. respectively. Reactors were operated for 24 days with 1 hour stirring by 1 rpm and 2 hours aeration per day. The lowering of the volume ratio of food wasted to chaff resulted in the reaction at higher reaction temperature and the elongation of the high temperature reaction period. The lowering of the volume ratio of food wastes to chaff resulted in the more faster pH increase. The lowering of the volume ratio of food wastes to chaff resulted in the more faster reduction in the weight and the volume of wastes. Salinities were condensed by reaction days. The final salinity of Control and the final range of salinities of chaff mixtures were 2.79%, and 2.18~2.37%. respectively.

• 사상체질의학회지
• /
• 제3권1호
• /
• pp.201-217
• /
• 1991

In order to investigate experimental effects of Yangkyuksanwha-Tang, which is the typical prescription for diseased SOYANGIN, on diabetes rats, the observation and measurement was made on the content of volume of blood glucose, total cholesterol, triglyceride, phospholipid, total protein, electrolyte($K^+$, $Na^+$) in serum, by dosing the cooked Y.S.T. to diabetic rats, induced by streptozotocin and following result was obtained. 1. The volume of blood glucose, in the diabetes rats, was decreased significantly, and remarkable decrease of blood glucose was shown in the Y.S.T. (12.5ml/kg) dosed group, after 4weeks of experiment. 2. The volume of total cholesterol of blood serum was decreased notably, especially remarkable reduce of total cholesterol was shown in the Y.S.T. (12.5ml/kg) dosed group after a week. 3. The volume of triglyceride in the blood serum of diabetic rats, induced by the streptozotocin was decreased after 4 weeks, and remarkable decrease was shown in the Y.S.T. (12.5ml/kg) dosed group after 2 weeks of experiment. 4. The volume of the phospholipid in the diabetes rats, was decreased significantly in the Y.S.T. (12.5ml/kg) dosed group after 2 weeks of experiment. 5. The volume of total protein of diabetes rats, was increased in all group, and the remarkable increase was shown in the Y.S.T. (12.5ml/kg) dosed group after 4 weeks. 6. The volume of the sodium in the Y.S.T. (12.5ml/kg) dosed group, was notable in each Y.S.T. dosed group (1.25ml/kg, 12.5ml/kg) after a week experiment. According to above results, It is expected that Y.S.T. applied to SOYANGIN, can be used for medical treatment of diabetes with effect. But because the effect can be somewhat different depending upon dosage, appropriate operation on clinic is needed, for the best curing effect.

• 한국수산과학회지
• /
• 제40권6호
• /
• pp.374-379
• /
• 2007

Two experiments were designed to examine short-term effects of human chorionic gonadotropin (hCG), and long-term effects of gonadotropin-releasing hormone agonist (GnRHa), $17{\alpha}-hydroxyprogesterone$ (17P), and $17{\alpha},20{\beta}-dihydroxy-4-pregnen-3-one\;(17,20{\beta}P)$, alone or in combination, on milt production of the starry flounder Platichthys stellatus. In the first experiment, fish were injected with either 200 IU hCG/kg body weight or the same volume of marine fish Ringer's solution (MFRS). In the second experiment, each fish was implanted with a blank cholesterol pellet (control), $200\;{\mu}g$ GnRHa, $500\;{\mu}g$ 17P, or $100\;{\mu}g\;17,20{\beta}P/kg$ body weight alone or in combination. In the first experiment, hCG injection resulted in an increase in the expressible milt volume and a decrease in the spermatocrit (Sct). After pellet implantation in the second experiment, the milt volume was increased in males treated with GnRHa, GnRHa+17P, or $GnRHa+17,20{\beta}P$. On day 7 after hormone pellet implantation, the milt volume began to increase, and on day 14, the milt volume in the $GnRHa+500\;{\mu}g$ 17P group was significantly higher than that in the control group. Compared with the control group, the hormone pellet-treated groups had a significant reduction in the mean Sct and sperm concentration (Sc) at day 7 after pellet implantation, while there were no differences in total sperm number. The results suggest that increases in milt volume are generally associated with decreases in Sct and SC, suggesting that the main mechanism for the increase in milt volume was milt hydration.

• The Korean Journal of Pain
• /
• 제27권4호
• /
• pp.334-338
• /
• 2014

Background: Lumbar transforaminal epidural steroid injections (TFESIs) are performed to provide symptom relief in patients with radicular pain. Recent articles suggested that injected volume itself have analgesic effects and higher volumes are associated with better outcomes. To date, few studies have been conducted to investigate the effects of volume. Therefore, well-designed controlled studies were necessary to confirm the effect of volume itself on pain relief. The purpose of this study was to examine the effectiveness of a forceful saline injection on lumbar TFESI using non-particulate steroids. Methods: Fifty consecutive patients with lumbar radicular pain were enrolled. The participants were allocated into one of two groups: dexamethasone with volume (Group DV) and dexamethasone alone (Group DO). The volume was delivered by a forceful injection of 5ml of normal saline. The primary end-point for this study was a VAS pain score and modified MacNab score indicating the rate of effectiveness at the four-week follow-up. Results: There were no significant post-procedural VAS differences between two groups (P = .252). The effectiveness rate among the patients was 47.8% in DV group, 34.8% in DO group, measured by modified MacNab score. The difference was not statistically significant (P = .117). Conclusions: A forceful saline injection did not have a significant effect during the treatment of radicular pain. Further studies with greater volumes and with additional techniques would offer a more conclusive perspective.