• Korea Trade Review
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• v.47 no.4
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• pp.35-52
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• 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.

• Journal of the Korean Solar Energy Society
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• v.31 no.1
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• pp.1-7
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• 2011

This study was accomplished to evaluate the performance of Multi Effect Distillation(MED) for solar thermal desalination system. It was designed Multi effect distillation with $3m^3$/day capacity and Shell&Tube type heat exchanger. Also, The effective heat transfer of Shell&Tube heat exchanger was used Cu(90%)-Ni(10%) corrugated tube. The parameters relating to the performance of Multi Effect Distillation are known as hot water flow rate. The experimental conditions for each parameters were $18^{\circ}C$ for sea water inlet temperature, $6m^3$/hour sea water inlet volume flow rate, $75^{\circ}C$ for hot water inlet temperature, 2.4, 3.6, and $4.8\;m^3$/hour for hot water inlet volume flow rate, respectively. The results are as follows, Development for Multi effect distillation was required about 40kW heat and 35kW cooling source to produce $3m^3$/day of fresh water. Based on the results of this study, It makes possible to secure economics of desalination system with solar energy which is basically needed development of high efficiency fresh water generator.

• The Journal of Internal Korean Medicine
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• v.33 no.1
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• pp.26-38
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• 2012

Objectives : The aim of this study was to investigate the effect of partial pyloric obstruction on body weight, gastric juice, gastric surface area and gastric edema in normal intact and/or vagotomized rats. Methods : Partial pyloric obstruction was performed by wrapping a non-absorbable rubber ring (D:6 mm, W:4 mm, T:1 mm) around the 1st portion of the duodenum. Vagotomy was performed by resecting the branches around the esophagogastric junction. Pre-post body weight differential, fasting gastric juice volume, gastric surface area and gastric edema were measured at 8 weeks and 20 weeks. For the effect of pyloric reperfusion the rubber ring was removed after 8 weeks and then an additional 12 weeks of observation was performed to the end of the 20-week experimental period. Results : In the initial 8 weeks observation, the effect of pylorus obstruction and/or vagotomy was significantly remarkable in the pylorus obstructed and vagotomized group; slowdown of weight gain, increase of fasting gastric juice volume, dilatation of gastric surface area and severe gastric edema were shown. In the remaining 12 weeks observation, the effect of reperfusion was significantly remarkable in the ring-removed antral dilated group; recovery of weight gain, decrease of gastric surface area and decrease of gastric edema were shown. However, gastric juice volume was not significantly different from the other group. Conclusions : Partial pyloric obstruction plays a aggravating role and the vagus nerve plays a protective role in body weight, gastric juice, gastric surface area, and gastric edema. Furthermore, pyloric valve dysfunction as an aggravating factor strengthened in defect of the vagus nerve. These results suggest that patients with both functional pyloric outlet obstruction and hypofunction of vagus nerve need to be diagnosed in good time and treated properly.

• Journal of Information Technology Services
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• v.19 no.2
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• pp.11-21
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• 2020

This study explores the effect of time-deals, i.e., online promotions with time limit. Recently many online/mobile shopping sites in China utilize so called hot deal marketing technique for a short duration at a specific time. The purpose of "time-deals" is to attract online shoppers with deep discounted price and induce consumers to purchase items. This paper examines the effect of time-deals on sales volume, firstly by comparing the sales volume of time-deal days with that of no time-deal days and secondly by comparing the sales volume of days before and after two types of time deals, usual time-deals and special time-deals, Although some prior research studied the role of time-deals in promoting consumers' purchase behavior, most used the experimental approach by building mock-up shopping sites and asking participants purchase intention. However, purchase intention does not always result in purchase behavior. This study extracted actual purchase data for four items on time-deals from an online shopping site in China. A comparison of sales volumes on time-deal days with no time-deal days has shown the significant difference in the sales volumes. This finding confirms the positive effect of time-deals on purchase behavior. This study has also found that special time-deals soak up near-future demands in advance and lower the sales after the special time-deal event, although there is no significant difference in sales before and after usual time-deals.

• The Korean Journal of Pain
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• v.27 no.4
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• pp.334-338
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• 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.

• Journal of the Korea Concrete Institute
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• v.19 no.5
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• pp.631-637
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• 2007

This study was to evaluate bond properties between high-strength steel fiber reinforced concrete and high strength steel rebar. An direct bond test were performed to evaluate the bond performance of high strength steel rebar in two types of high-strength concrete with steel fiber volume fraction (0, 20, $40kg/m^3$). Also, relative bond strength was defined to determine the effect of steel fiber volume fraction on bond strength. The bond test results showed that the bond performance of high strength steel rebar and high strength concrete tended to increase with higher compressive strength and steel fiber volume fraction. Relative bond strength which performed to analyze effect of steel fiber volume fraction showed increased relative bond strength with increased steel fiber volume fraction.

• Korean Journal of Materials Research
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• v.25 no.11
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• pp.583-589
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• 2015

This paper presents a study on the room- and low-temperature impact toughness of hypoeutectoid steels with ferrite-pearlite structures. Six kinds of hypoeutectoid steel specimens were fabricated by varying the carbon content and austenitizing temperature to investigate the effect of microstructural factors such as pearlite volume fraction, interlamellar spacing, and cementite thickness on the impact toughness. The pearlite volume fraction usually increased with increasing carbon content and austenitizing temperature, while the pearlite interlamellar spacing and cementite thickness mostly decreased with increasing carbon content and austenitizing temperature. The 30C steel with medium pearlite volume fraction and higher manganese content, on the other hand, even though it had a higher volume fraction of pearlite than did the 20C steel, showed a better low-temperature toughness due to its having the lowest ductile-brittle transition temperature. This is because various microstructural factors in addition to the pearlite volume fraction largely affect the ductile-brittle transition temperature and low-temperature toughness of hypoeutectoid steels with ferrite-pearlite structure. In order to improve the room- and low-temperature impact toughness of hypoeutectoid steels with different ferrite-pearlite structures, therefore, more systematic studies are required to understand the effects of various microstructural factors on impact toughness, with a viewpoint of ductile-brittle transition temperature.

• Journal of Applied Tourism Food and Beverage Management and Research
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• v.15 no.2
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• pp.57-72
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• 2004

This study is carried out to investigate the effect of any periods in the freezer and the product of value, moisture content, baking loss, specific volume loaf in manufncturing process thereof. The moisture content of the croissant slightly decreased as the periods passed in the freezer. And as passed periods frozen croissant dough dried naturally by the freezer fan. 1. As frozen periods passed croissant dough decreased moisture content and loaf volume. The volume is relation to the molsture content and croissant dough' gluten. Yeast is active but croissant dough is dried so pastry margarine's moisture vaporized little by little. 2. 1 day frozen bench time provided maximum specific loaf volume while croissant shape was unsettled, moisture content was highest. At the same dough croissant hardness had very sofi crust. 3. 1week and 2weets frozen dough had specific loaf volume and hardness with proper crust color. As the proper bench time provided best shape of croissant, color. 4. 4weeks and 8weeks frozen dough had over-al] value of croissant accelerating older product. As the same result, over Sweets frozen periods product were not available for sale and serving to customers. 5. By the sensory evaluation tests, over-all croissant as 1 week, 2weeks were significantly higher quality those than 6. 1day, 4weeks and 8weeks. Textural properties of croissant over 4weeks frozen periods so hard for every panel. According to the study, not croissant dough but also any other frozen dough(ex.Danish, brioche etc.)have to need proper bench time and 1week or 2weeks circulation making method have to given encouragement to practical pastry industry. Add to this study using only for frozen dough yeast instead of using fresh and instant

• Journal of Navigation and Port Research
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• v.37 no.6
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• pp.719-725
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• 2013

Northeast Asia region is becoming the hub of world trade with China as the center. Integration of this region's economy is now visualized, domestic trade and international division of labor will be more invigorated. Especially on electrical and electronics industry is a large proportion of the trading volume between Korea and China and now, Present condition of electrical and electronics trading industry can effect on whole trading industry. In this study, conducting analysis of the current Korea-China electrical and electronics industry trading and advanced research, and find out the implication to trading volume with the panel analysis. As the results Korean/Chinese GDP, revealed comparative advantage, and foreign direct investment have an effect on the trading volume.

• The Journal of Korean Obstetrics and Gynecology
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• v.34 no.3
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• pp.137-156
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• 2021

Objectives: The purpose of this study is to assess the effect of taking herbal medicine for the postpartum lactation. Methods: We searched 9 databases for recent three years, that contained four english, two chinese, one japanese and two korean database from September 17, 2016 to December 31, 2020. Randomized controlled trials (RCTs) were eligible. Measurement of outcome included total curative effective rate, volume of lactation, volume of milk supplement, and serum prolactin concentration. The risk of bias was assessed by two independent authors using the Cochrane risk of bias tool. Results: Total 725 of studies was screened, 11 RCTs were finally selected. Number of participants per study ranged from 60 to 257. The treatment group of taking a herbal medicine is effective for improving total curative effective rate, volume of lactation, volume of milk supplement, and serum prolactin concentration compared with control group. Because most of the studies had considerable heterogeneity in terms of type of intervention and comparison for outcome measurement, meta analysis for quantitative analysis was impossible. Conclusions: This studies showed that taking a herbal medicine is effective on increasing volume of lactation and speeding up the start of the first breastfeeding. However, included studies suffered from incomplete reporting, high or unclear risk of bias and substantial heterogeneity between studies. In the Future, further high-quality RCTs are needed to prove effectiveness of herbal medicine for breastfeeding and reduce the risk of bias.