• Journal of the Korean Society of Marine Environment & Safety
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• v.29 no.5
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• pp.417-426
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• 2023

Rapid climate change has resulted in glacial retreat and increased meltwater inputs in the Antarctic Peninsula, including King George Island where Marian Cove is located. Consequently, these phenomena are expected to induce changes in the water column light properties, which in turn will affect phytoplankton communities. To comprehend the effects of glacial retreat on the marine ecosystem in Marian Cove, we investigated on phytoplankton biomass (chlorophyll-a, chl-a) and various environment parameters in this area in December 2021 and January 2022. The average temperature at the euphotic depth in January 2022 (1.41 ± 0.13 ℃) was higher than that in December 2021 (0.87 ± 0.17 ℃). Contrastingly, the average salinity was lower in January 2022 (33.9 ± 0.10 psu) than in December 2021 (34.1 ± 0.12 psu). Major nutrients, including dissolved inorganic nitrogen, phosphate, and silicate, were sufficiently high, and thus, did not act as limiting factors for phytoplankton biomass. In December 2021 and January 2022, the mean chl-a concentrations were 1.03 ± 0.64 and 0.66 ± 0.15㎍ L^-1, respectively. The mean concentration of suspended particulate matter (SPM) was 24.9 ± 3.54 mgL^-1 during the study period, with elevated values observed in the vicinity of the inner glacier. However, relative lower chl-a concentrations were observed near the inner glacier, possibly due to high SPM load from the glacier, resulting in reduced light attenuation by SPM shading. Furthermore, the proportion of nanophytoplankton exceeded 70% in the inner cove, contributing to elevated mean fractions of nanophytoplankton in the glacier retreat marine ecosystem. Overall, our study indicated that freshwater and SPM inputs from glacial meltwater may possibly act as main factors controlling the dynamics of phytoplankton communities in glacier retreat areas. The findings may also serve as fundamental data for better understanding the carbon cycle in Marian Cove.

• Journal of Bio-Environment Control
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• v.31 no.4
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• pp.485-496
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• 2022

Modern agriculture is being transformed into smart agriculture to maximize production efficiency along with changes in the 4th industrial revolution. However, rural areas in Korea are facing challenges of aging, low fertility, and population outflow, making it difficult to transition to smart agriculture. Among ICT technologies, simulation allows users to observe or experience the results of their choices through imitation or reproduction of reality. The combination of the three-dimension (3D) model and the greenhouse simulator enable a 3D experience by virtual greenhouse for fruits and vegetable cultivation. At the same time, it is possible to visualize the greenhouse under various cultivation or climate conditions. The objective of this study is to apply the greenhouse climate management model for simulation development that can visually see the state of the greenhouse environment under various micrometeorological properties. The numerical solution with the mathematical model provided a dynamic change in the greenhouse environment for a particular greenhouse design. Light intensity, crop transpiration, heating load, ventilation rate, the optimal amount of CO₂ enrichment, and daily light integral were calculated with the simulation. The results of this study are being built so that users can be linked through a web page, and software will be designed to reflect the characteristics of cladding materials and greenhouses, cultivation types, and the condition of environmental control facilities for customized environmental control. In addition, environmental information obtained from external meteorological data, as well as recommended standards and set points for each growth stage based on experiments and research, will be provided as optimal environmental factors. This simulation can help growers, students, and researchers to understand the ICT technologies and the changes in the greenhouse microclimate according to the growing conditions.

• Clinical and Experimental Pediatrics
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• v.50 no.12
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• pp.1225-1230
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• 2007

Purpose : Multiple transfusions in patients with chronic anemia can result in excessive iron deposition in tissues and organs. Effective iron chelation therapy in chronically transfused patients can only be achieved when iron chelators remove sufficient amounts of iron equivalent to those accumulated in the body from transfusions, thus leading to maintain body iron load at a non-toxic level. This study was retrospectively carried out to investigate the effect of intravenous iron chelation therapy with deferoxamine in patients who have received multiple transfusions. Methods : From March 2005 to January 2007, 15 patients who have received multiple transfusions were included in this study. Transfusion dependent patients were defined as those receiving >1 packed red blood cell (RBC) units/month for at least 6 months. They received intravenous deferoxamine for 7 days (10-30 mg/kg/day, 24 hour continuous infusions). Before and after deferoxamine infusions and 3 months later, we compared serum iron, TIBC, and ferritin in transfusion dependent patients and transfusion independent patients. Results : There were 6 males and 9 females and their age range was 5.6-21.3 (median 8.3) years. Transfusion dependent patients were 7 and 8 were transfusion independent states after stem cell transplantation or chemotherapy. There was no significant change in ferritin level after deferoxamine treatment for the transfusion dependent patients but significant falling of ferritin level was observed for the transfusion independent patients 3 months later compared with baseline ferritin level (P=0.046). Some adverse events were observed but symptoms were mild and tolerable. Conclusion : Seven days of intravenous deferoxamine was safe and effective in transfusion independent patients. In transfusion dependent patients, chelation therapy should be maintained, in order to minimize or prevent iron accumulation and storage in the tissues.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.6
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• pp.288-296
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• 2019

Radiation cooling has used ceilings or floors as cooling surfaces. In such cases, to avoid moisture condensation on the surface, the surface temperature needs be higher than the dew point temperature or an additional dehumidifier is added. In this study, with a goal for residential application, intentional moisture condensation on the cooling surface was attempted, which increased the cooling capacity and improved the indoor comfortness. This method included two separate refrigeration cycles - convection-type dehumidifying cycle and the panel cooling cycle. Test results on the panel cooling cycle showed that, at the standard outdoor ($35^{\circ}C/24^{\circ}C$) and indoor ($27^{\circ}C/19.5^{\circ}C$) condition, the refrigerant flow rate was 8.8 kg/h, condensation temperature was $51^{\circ}C$, evaporation temperature was $8.8^{\circ}C$, cooling capacity was 376 W and COP was 1.75. Furthermore, the panel temperature was uniform within $1^{\circ}C$ (between $13^{\circ}C$ and $14^{\circ}C$). As the relative humidity decreased, the cooling capacity decreased. However, the power consumption remained approximately constant. In the convection-type dehumidification cycle, the refrigerant flow rate was 21.1 kg/h, condensation temperature was $61^{\circ}C$, evaporation temperature was $5.0^{\circ}C$, cooling capacity was 949 W and COP was 2.11 at the standard air condition. When both the radiation panel cooling and the dehumidification cycle operated simultaneously, the cooling capacity of the radiation panel cycle was 333 W and that of the dehumidification cycle was 894 W, and the COP was 1.89. As the fan flow rate decreased, both the cooling capacity of the radiation panel and the dehumidification cycle decreased, with that of the dehumidification cycle decreasing at a higher rate. Finally, a possible control logic depending on the change of the cooling load was proposed based on the results of the present study.

• Journal of Bio-Environment Control
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• v.5 no.2
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• pp.215-235
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• 1996

The thermal analysis by mathematical model simulation makes it possible to reasonably predict heating and/or cooling requirements of certain greenhouses located under various geographical and climatic environment. It is another advantages of model simulation technique to be able to make it possible to select appropriate heating system, to set up energy utilization strategy, to schedule seasonal crop pattern, as well as to determine new greenhouse ranges. In this study, the control pattern for greenhouse microclimate is categorized as cooling and heating. Dynamic model was adopted to simulate heating requirements and/or energy conservation effectiveness such as energy saving by night-time thermal curtain, estimation of Heating Degree-Hours(HDH), long time prediction of greenhouse thermal behavior, etc. On the other hand, the cooling effects of ventilation, shading, and pad ||||&|||| fan system were partly analyzed by static model. By the experimental work with small size model greenhouse of 1.2m$\times$2.4m, it was found that cooling the greenhouse by spraying cold water directly on greenhouse cover surface or by recirculating cold water through heat exchangers would be effective in greenhouse summer cooling. The mathematical model developed for greenhouse model simulation is highly applicable because it can reflects various climatic factors like temperature, humidity, beam and diffuse solar radiation, wind velocity, etc. This model was closely verified by various weather data obtained through long period greenhouse experiment. Most of the materials relating with greenhouse heating or cooling components were obtained from model greenhouse simulated mathematically by using typical year(1987) data of Jinju Gyeongnam. But some of the materials relating with greenhouse cooling was obtained by performing model experiments which include analyzing cooling effect of water sprayed directly on greenhouse roof surface. The results are summarized as follows : 1. The heating requirements of model greenhouse were highly related with the minimum temperature set for given greenhouse. The setting temperature at night-time is much more influential on heating energy requirement than that at day-time. Therefore It is highly recommended that night- time setting temperature should be carefully determined and controlled. 2. The HDH data obtained by conventional method were estimated on the basis of considerably long term average weather temperature together with the standard base temperature(usually 18.3$^{\circ}C$). This kind of data can merely be used as a relative comparison criteria about heating load, but is not applicable in the calculation of greenhouse heating requirements because of the limited consideration of climatic factors and inappropriate base temperature. By comparing the HDM data with the results of simulation, it is found that the heating system design by HDH data will probably overshoot the actual heating requirement. 3. The energy saving effect of night-time thermal curtain as well as estimated heating requirement is found to be sensitively related with weather condition: Thermal curtain adopted for simulation showed high effectiveness in energy saving which amounts to more than 50% of annual heating requirement. 4. The ventilation performances doting warm seasons are mainly influenced by air exchange rate even though there are some variations depending on greenhouse structural difference, weather and cropping conditions. For air exchanges above 1 volume per minute, the reduction rate of temperature rise on both types of considered greenhouse becomes modest with the additional increase of ventilation capacity. Therefore the desirable ventilation capacity is assumed to be 1 air change per minute, which is the recommended ventilation rate in common greenhouse. 5. In glass covered greenhouse with full production, under clear weather of 50% RH, and continuous 1 air change per minute, the temperature drop in 50% shaded greenhouse and pad ＆ fan systemed greenhouse is 2.6$^{\circ}C$ and.6.1$^{\circ}C$ respectively. The temperature in control greenhouse under continuous air change at this time was 36.6$^{\circ}C$ which was 5.3$^{\circ}C$ above ambient temperature. As a result the greenhouse temperature can be maintained 3$^{\circ}C$ below ambient temperature. But when RH is 80%, it was impossible to drop greenhouse temperature below ambient temperature because possible temperature reduction by pad ||||&|||| fan system at this time is not more than 2.4$^{\circ}C$. 6. During 3 months of hot summer season if the greenhouse is assumed to be cooled only when greenhouse temperature rise above 27$^{\circ}C$, the relationship between RH of ambient air and greenhouse temperature drop($\Delta$T) was formulated as follows : $\Delta$T= -0.077RH＋7.7 7. Time dependent cooling effects performed by operation of each or combination of ventilation, 50% shading, pad ＆ fan of 80% efficiency, were continuously predicted for one typical summer day long. When the greenhouse was cooled only by 1 air change per minute, greenhouse air temperature was 5$^{\circ}C$ above outdoor temperature. Either method alone can not drop greenhouse air temperature below outdoor temperature even under the fully cropped situations. But when both systems were operated together, greenhouse air temperature can be controlled to about 2.0-2.3$^{\circ}C$ below ambient temperature. 8. When the cool water of 6.5-8.5$^{\circ}C$ was sprayed on greenhouse roof surface with the water flow rate of 1.3 liter/min per unit greenhouse floor area, greenhouse air temperature could be dropped down to 16.5-18.$0^{\circ}C$, whlch is about 1$0^{\circ}C$ below the ambient temperature of 26.5-28.$0^{\circ}C$ at that time. The most important thing in cooling greenhouse air effectively with water spray may be obtaining plenty of cool water source like ground water itself or cold water produced by heat-pump. Future work is focused on not only analyzing the feasibility of heat pump operation but also finding the relationships between greenhouse air temperature(T$_{g}$ ), spraying water temperature(T$_{w}$ ), water flow rate(Q), and ambient temperature(T$_{o}$).

• Tuberculosis and Respiratory Diseases
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• v.43 no.2
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• pp.201-209
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• 1996

Background : Auto-PEEP which develops when expiratory lung emptying is not finished until the beginning of next inspiration is frequently found in patients on mechanical ventilation. Its presence imposes increased risk of barotrauma and hypotension, as well as increased work of breathing (WOB) by adding inspiratory threshold load and/or adversely affecting to inspiratory trigger sensitivity. The aim of this study is to evaluate the relationship of auto-PEEP with WOB and to evaluate the effect of PEEP applied by ventilator (external PEEP) on WOB in patients with auto-PEEP. Method : 15 patients, who required mechanical ventilation for management of acute respiratory failure, were studied. First, the differences in WOB and other indices of respiratory mechanics were examined between 7 patients with auto-PEEP and 8 patients without auto-PEEP. Then, we applied the 3 cm $H_2O$ of external PEEP to patients with auto-PEEP and evaluated its effects on lung mechanics as well as WOB. Indices of respiratory mechanics including tidal volume ($V_T$), repiratory rate, minute ventilation ($V_E$), peak inspiratory flow rate (PIFR), peak expiratory flow rate (PEFR), peak inspiratory pressure (PIP), $T_I/T_{TOT}$, auto-PEEP, dynamic compliance of lung (Cdyn), expiratory airway resistance (RAWe), mean airway resistance (RAWm), $p_{0.1}$, work of breathing performed by patient (WOB), and pressure-time product (PTP) were obtained by CP-100 Pulmonary Monitor (Bicore, USA). The values were expressed as mean $\pm$ SEM (standard error of mean). Results : 1) Comparison of WOB and other indices of respiratory mechanics in patients with and without auto-PEEP : There was significant increase in WOB ($l.71{\pm}0.24$ vs $0.50{\pm}0.19\;J/L$, p=0.007), PTP ($317{\pm}70$ vs $98{\pm}36\;cm$ $H_2O{\cdot}sec/min$, p=0.023), RAWe ($35.6{\pm}5.7$ vs $18.2{\pm}2.3\;cm$ H2O/L/sec, p=0.023), RAWm ($28.8{\pm}2.5$ vs $11.9{\pm}2.0cm$ H2O/L/sec, p=0.001) and $P_{0.1}$ ($6.2{\pm}1.0$ vs 2.9+0.6 cm H2O, p=0.021) in patients with auto-PEEP compared to patients without auto-PEEP. The differences of other indices including $V_T$, PEFR, $V_E$ and $T_I/T_{TOT}$ showed no significance. 2) Effect of 3 cm $H_2O$ external PEEP on respiratory mechanics in patients with auto-PEEP : When 3 cm $H_2O$ of external PEEP was applied, there were significant decrease in WOB ($1.71{\pm}0.24$ vs $1.20{\pm}0.21\;J/L$, p=0.021) and PTP ($317{\pm}70$ vs $231{\pm}55\;cm$ $H_2O{\cdot}sec/min$, p=0.038). RAWm showed a tendency to decrease ($28.8{\pm}2.5$ vs $23.9{\pm}2.1\;cm$ $H_2O$, p=0.051). But PIP was increased with application of 3 cm $H_2O$ of external PEEP ($16{\pm}2$ vs $22{\pm}3\;cm$ $H_2O$, p=0.008). $V_T$, $V_E$, PEFR, $T_I/T_{TOT}$ and Cdyn did not change significantly. Conclusion : The presence of auto-PEEP in mechanically ventilated patients was accompanied with increased WOB performed by patient, and this WOB was decreased by 3 cm $H_2O$ of externally applied PEEP. But, with 3 cm $H_2O$ of external PEEP, increased PIP was noted, implying the importance of close monitoring of the airway pressure during application of external PEEP.

• Korean Journal of Heritage: History & Science
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• v.48 no.3
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• pp.96-119
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• 2015

This research has studied the changes of Gwi-po(轉角包) by taking the cases of China's medieval wooden buildings as objects. The purpose of the study is to examine the time-periodic transition process of Gwi-po through the cases of 71 wooden buildings which were built from Tang(唐) dynasty(AD 618~690 & 705~907) until Jin(金) dynasty(AD 1115~1234) and also designated as 'Major Historical and Cultural Sites Protected at the National Level'. This research has taken note of various frame types of Jwau-dae(左右隊), which are architectural components of Gwi-po, to study the changes and development process of Gwi-po. The results are as follows. An important factor in the transformations of Gwi-po format is the changes in perception of the craftsmen about Jwau-dae, who took charge in the building process. In the early periods, the principles of Yidou sanshen dougong(一斗三升) in constructing ancons of Gwi-po had been well-maintained, while there appeared many different types of Gwi-po in later periods, due to the usage of Jwau-dae and $Shu{\check{a}}$ $t{\acute{o}}u$(?頭) in each Chulmok of Gwi-po. Transitional types of Gwi-po, which were evolved from the earlier ones, are divided into 3 categories by different forms of Jwau-dae, placed on odd number stages. The first one is 'none-$f{\bar{a}}ng$ $t{\acute{o}}u$(無枋頭) type' of Song(AD 960~1127, 1127~1279) and Liao dynasty(AD 907~1125) buildings, which doesn't have $f{\bar{a}}ng$ $t{\acute{o}}u$(枋頭)s, for the reason that Jwau-dae(左右隊) is in direct contact with Gwihan-dae(耳限大). The second one is '$Shu{\check{a}}$ $t{\acute{o}}u$ $f{\bar{a}}ng$ $t{\acute{o}}u$(?頭枋頭) type' of Song(AD 960~1127, 1127~1279) and Jin dynasty(AD 1115~1234), that has $f{\bar{a}}ng$ $t{\acute{o}}u$(枋頭)s of Jwau-dae(左右隊) identical to $Shu{\check{a}}$ $t{\acute{o}}u$(?頭) in form. The last one is '$Xi{\check{a}}o$ $g{\check{o}}ng$ $t{\acute{o}}u$(小?頭) type' of Jin(AD 1115~1234) and Yuan dynasty(AD 1271~1368), which has $f{\bar{a}}ng$ $t{\acute{o}}u$(枋頭)s of Jwau-dae identical to $Xi{\check{a}}o$ $g{\check{o}}ng$ $t{\acute{o}}u$(小?頭) in form. The earlier forms of Gwi-po, which appeared between Tang dynasty(AD 618~690 & 705~907) and Five Dynasties periods(907~960) went through transitional forms of 'non-$f{\bar{a}}ng$ $t{\acute{o}}u$(無枋頭) type', '$Shu{\check{a}}$ $t{\acute{o}}u$ $f{\bar{a}}ng$ $t{\acute{o}}u$(?頭枋頭) type' and '$Xi{\check{a}}o$ $g{\check{o}}ng$ $t{\acute{o}}u$(小?頭) type' and finally had its form settled between Yuan(元, AD 1271~1368) and Ming(明. AD 1368~1644) dynasty periods. In Liao(遼) dynasty period(AD 907~1125), as the buildings got bigger and the tendency of longer eave-exposure was implemented, there grew a certain need to structurally reinforce Gwi-po, on which load of the whole roof is concentrated. Especially, the transition from Tōuxīn $z{\grave{a}}o$(偸心造) style to Jì xīn $z{\grave{a}}o$(計心造) style in this period had a great influence on standardization of Gwi-po, along with None-${\acute{A}}ng$(無仰) style. Furthermore, Wing-type Gong(翼型?), which developed in Liao dynasty(AD 907~1125), is also thought to have had a great influence on the transition from Tōuxīn $z{\grave{a}}o$(偸心造) style to Jì xīn $z{\grave{a}}o$(計心造) style by changing the forms of Gongs(?), such as Gwi-po. However, unlike None-${\acute{A}}ng$(無仰) style, there occurred a gradual change from '$Shu{\check{a}}$ $t{\acute{o}}u$ $f{\bar{a}}ng$ $t{\acute{o}}u$(?頭枋頭) type' to '$Xi{\check{a}}o$ $g{\check{o}}ng$ $t{\acute{o}}u$(小?頭) type' of Gwi-po in $Xi{\grave{a}}$ ${\acute{a}}ng$ style.

• Journal of Global Scholars of Marketing Science
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• v.20 no.1
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• pp.89-97
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• 2010

This study researches the effects of common features on a no-choice option with respect to regulatory focus theory. The primary interest is in three factors and their interrelationship: common features, no-choice option, and regulatory focus. Prior studies have compiled vast body of research in these areas. First, the "common features effect" has been observed bymany noted marketing researchers. Tversky (1972) proposed the seminal theory, the EBA model: elimination by aspect. According to this theory, consumers are prone to focus only on unique features during comparison processing, thereby dismissing any common features as redundant information. Recently, however, more provocative ideas have attacked the EBA model by asserting that common features really do affect consumer judgment. Chernev (1997) first reported that adding common features mitigates the choice gap because of the increasing perception of similarity among alternatives. Later, however, Chernev (2001) published a critically developed study against his prior perspective with the proposition that common features may be a cognitive load to consumers, and thus consumers are possible that they are prone to prefer the heuristic processing to the systematic processing. This tends to bring one question to the forefront: Do "common features" affect consumer choice? If so, what are the concrete effects? This study tries to answer the question with respect to the "no-choice" option and regulatory focus. Second, some researchers hold that the no-choice option is another best alternative of consumers, who are likely to avoid having to choose in the context of knotty trade-off settings or mental conflicts. Hope for the future also may increase the no-choice option in the context of optimism or the expectancy of a more satisfactory alternative appearing later. Other issues reported in this domain are time pressure, consumer confidence, and alternative numbers (Dhar and Nowlis 1999; Lin and Wu 2005; Zakay and Tsal 1993). This study casts the no-choice option in yet another perspective: the interactive effects between common features and regulatory focus. Third, "regulatory focus theory" is a very popular theme in recent marketing research. It suggests that consumers have two focal goals facing each other: promotion vs. prevention. A promotion focus deals with the concepts of hope, inspiration, achievement, or gain, whereas prevention focus involves duty, responsibility, safety, or loss-aversion. Thus, while consumers with a promotion focus tend to take risks for gain, the same does not hold true for a prevention focus. Regulatory focus theory predicts consumers' emotions, creativity, attitudes, memory, performance, and judgment, as documented in a vast field of marketing and psychology articles. The perspective of the current study in exploring consumer choice and common features is a somewhat creative viewpoint in the area of regulatory focus. These reviews inspire this study of the interaction possibility between regulatory focus and common features with a no-choice option. Specifically, adding common features rather than omitting them may increase the no-choice option ratio in the choice setting only to prevention-focused consumers, but vice versa to promotion-focused consumers. The reasoning is that when prevention-focused consumers come in contact with common features, they may perceive higher similarity among the alternatives. This conflict among similar options would increase the no-choice ratio. Promotion-focused consumers, however, are possible that they perceive common features as a cue of confirmation bias. And thus their confirmation processing would make their prior preference more robust, then the no-choice ratio may shrink. This logic is verified in two experiments. The first is a $2{\times}2$ between-subject design (whether common features or not X regulatory focus) using a digital cameras as the relevant stimulus-a product very familiar to young subjects. Specifically, the regulatory focus variable is median split through a measure of eleven items. Common features included zoom, weight, memory, and battery, whereas the other two attributes (pixel and price) were unique features. Results supported our hypothesis that adding common features enhanced the no-choice ratio only to prevention-focus consumers, not to those with a promotion focus. These results confirm our hypothesis - the interactive effects between a regulatory focus and the common features. Prior research had suggested that including common features had a effect on consumer choice, but this study shows that common features affect choice by consumer segmentation. The second experiment was used to replicate the results of the first experiment. This experimental study is equal to the prior except only two - priming manipulation and another stimulus. For the promotion focus condition, subjects had to write an essay using words such as profit, inspiration, pleasure, achievement, development, hedonic, change, pursuit, etc. For prevention, however, they had to use the words persistence, safety, protection, aversion, loss, responsibility, stability etc. The room for rent had common features (sunshine, facility, ventilation) and unique features (distance time and building state). These attributes implied various levels and valence for replication of the prior experiment. Our hypothesis was supported repeatedly in the results, and the interaction effects were significant between regulatory focus and common features. Thus, these studies showed the dual effects of common features on consumer choice for a no-choice option. Adding common features may enhance or mitigate no-choice, contradictory as it may sound. Under a prevention focus, adding common features is likely to enhance the no-choice ratio because of increasing mental conflict; under the promotion focus, it is prone to shrink the ratio perhaps because of a "confirmation bias." The research has practical and theoretical implications for marketers, who may need to consider common features carefully in a practical display context according to consumer segmentation (i.e., promotion vs. prevention focus.) Theoretically, the results suggest some meaningful moderator variable between common features and no-choice in that the effect on no-choice option is partly dependent on a regulatory focus. This variable corresponds not only to a chronic perspective but also a situational perspective in our hypothesis domain. Finally, in light of some shortcomings in the research, such as overlooked attribute importance, low ratio of no-choice, or the external validity issue, we hope it influences future studies to explore the little-known world of the "no-choice option."

• FLOWER RESEARCH JOURNAL
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• v.18 no.3
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• pp.186-192
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• 2010

An infrared heating system, installed in a small venlo-type glasshouse ($280m^2$) in Gyeongsang National University, Jinju, Korea, was used to investigate its heating effect with potted Phalaenopsis, Schefflera arboricola 'Hongkong', Ficus elastica 'Variegata', and Rosa hybrida 'Yellow King' as the test plants. Temperature changes in test plants with the system turned 'On' and 'Off' were measured by using an infrared camera and the consumption of electricity by this infrared heating system was measured and analyzed. In potted Phalaenopsis, when the set air temperature of the greenhouse was $18^{\circ}C$, temperature of leaves and the growing medium were $22.8{\sim}27^{\circ}C$ and $21.3{\sim}24.3^{\circ}C$, respectively. In such tall plants as Schefflera arboricola 'Hongkong' and Ficus elastica 'Variegata', the upper part showed the highest temperature of 24.0 and $26.9^{\circ}C$, respectively. From the results of temperature change measurements, the plant temperatures were near or above the set point temperatures with some fluctuations depending on the position or distance from the infrared heating system. When air temperature between night and dawn dropped sharply, plant temperatures were maintained close to the set temperature ($18^{\circ}C$). There was a significant difference between 'On' and 'Off' states of the infrared heating system in average temperatures of root zone and leaf: 21.8 and $17.8^{\circ}C$ with the system 'On' and 20.4 and $15.5^{\circ}C$ with the system 'Off', respectively, in a cut rose Rosa hybrida 'Yellow King'. The heating load was about $24,850{\sim}35,830kcal{\cdot}h^{-1}$, which comes to about 27,000~40,000 won in Korean currency when calculated in terms of the cost of heating by a hot water heating system heated by petroleum. The cost for heating by the infrared heating system was about 35% of that of a hot water heating system. With the infrared heating system, the air temperature during the night was maintained slightly lower than the set point air temperature, probably due to the lack of air tightness of the glasshouse. Therefore, glasshouses with an infrared heating system requires further investigation including the installation space of the heat-emitting units, temperature sensor positions, and convection.