• Title/Summary/Keyword: Ventilation Performance

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A comparative study of risk according to smoke control flow rate and methods in case of train fire at subway platform (지하철 승강장에서 열차 화재 시 제연풍량 및 방식에 따른 위험도 비교 연구)

  • Ryu, Ji-Oh;Lee, Hu-Yeong
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.24 no.4
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    • pp.327-339
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    • 2022
  • The purpose of this study is to present the effective smoke control flow rate and mode for securing safety through quantitative risk assessment according to the smoke control flow rate and mode (supply or exhaust) of the platform when a train fire occurs at the subway platform. To this end, a fire outbreak scenario was created using a side platform with a central staircase as a model and fire analysis was performed for each scenario to compare and analyze fire propagation characteristics and ASET, evacuation analysis was performed to predict the number of deaths. In addition, a fire accident rate (F)/number of deaths (N) diagram (F/N diagram) was prepared for each scenario to compare and evaluate the risk according to the smoke control flow rate and mode. In the ASET analysis of harmful factors, carbon monoxide, temperature, and visible distance determined by performance-oriented design methods and standards for firefighting facilities, the effect of visible distance is the largest, In the case where the delay in entering the platform of the fire train was not taken into account, the ASET was analyzed to be about 800 seconds when the air flow rate was 4 × 833 m3/min. The estimated number of deaths varies greatly depending on the location of the vehicle of fire train, In the case of a fire occurring in a vehicle adjacent to the stairs, it is shown that the increase is up to three times that of the vehicle in the lead. In addition, when the smoke control flow rate increases, the number of fatalities decreases, and the reduction rate of the air supply method rather than the exhaust method increases. When the supply flow rate is 4 × 833 m3/min, the expected number of deaths is reduced to 13% compared to the case where ventilation is not performed. As a result of the risk assessment, it is found that the current social risk assessment criteria are satisfied when smoke control is performed, and the number of deaths is the flow rate 4 × 833 m3/min when smoke control is performed at 29.9 people in 10,000 year, It was analyzed that it decreased to 4.36 people.

The Work and Job Satisfaction of Paramedics in the Emergency Room of University Hospitals (대학병원 응급실 내 1급 응급구조사의 업무와 직무만족도)

  • Lee, Ok-Hee
    • The Korean Journal of Emergency Medical Services
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    • v.15 no.1
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    • pp.47-63
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    • 2011
  • Purpose : This research is to examine the work and job satisfaction of paramedics in the emergency room of university hospitals. This research is done to provide basic data needed for establishing work realms of paramedics in hospitals and to enhance their degree of satisfaction. Methods : Research questionnaire survey was conducted on 141 paramedics working in the emergency room of 32 university hospitals from August 24, 2010 to September 30, 2010 through direct visits and telephone interviews or email to explain the purpose of this research and assurance of confidentiality of responses on the questionnaires. As the tool for the degree of job satisfaction, 'The Index of Work Satisfaction' developed by Slavitt, et al(1978) and revised and supplemented by Soon-shim Kim and Hye-ran Kwon(2002) was used. The collected data were analyzed by evaluating frequency, percentage, mean, standard deviation, t-test and ANOVA, Cronbach's $\alpha$ by using SPSS WIN 18.0 program. Results : 1. Investigating the work and role of paramedics in the emergency room of university hospitals, electrocardiogram(EKG) was found to be highest with $\alpha$ was widely used with the rate of patient evaluation and test area. In the medical treatment for patients area, cardiopulmonary resuscitation(CPR) with 95%(134 persons) and ventilation assistance through ambu bagging(BVM) with 95%(134 persons) were found to be high. $\alpha$ were performed. In the role within the hospital and other areas, a member of CPR team in the hospital accounted for 78%(110 persons). 2. In the measurements of the job satisfaction of paramedics working at university hospitals, the total mean score was 2.91. The mean score in each question area indicated: section on job 3.48, autonomy 3.05, interaction 3.01, organizational demand 2.85, working conditions 2.67, salaries 2.40. This result obviously demonstrates the work of paramedics itself was most satisfied but the salaries were most dissatisfied. 3. In the measurements of the job satisfaction of paramedics working at university hospitals, job satisfaction based on the general characteristics showed significant difference in age (F=6.547, p=.002), gender (F=4.436, p=.000) marital status (F=-3.270, p= .001), religion (F=2.041, p= .043), motive for application (F=3.603, p= .015), and salary (F=6.658, p= .000). 대학병원 응급실 내 1급 응급구조사의 업무와 직무만족도 The Journal of the Korean Society of Emergency Medical Technology Vol. 15 (1) 63 4. In the measurements of the job satisfaction of paramedics working at university hospitals, job satisfaction based on the working environmental characteristics showed significant difference in total number of paramedics (F=3.779, p= .012), form of employment (F=5.601, p= .001), existence or non-existence of intention to change jobs (F=-4.037, p= .000). Conclusion : The work of paramedics in the emergency room of university hospitals consists of lots of treatment processes after specialized diagnosis and performance of professionally subdivided works. However, current legislation does not reflect such circumstances to which paramedics are exposed; thus, it should be considered for further revision and modification. The degree of job satisfaction of paramedics in the emergency room of university hospitals was high but low in salaries and working conditions were the weak points. The measures to enhance their degree of job satisfaction should be taken though improvement of labor conditions such as consideration of the rate of increase in salaries, compensation for overtime work, providing rest areas, improvement of current employment system, and conversion of temporary employees into regular employees.

Clinical Value of a Desktop Spirometer (HI-801) for Spirometry Screening (선별 검사를 위한 탁상용 폐활량기 (HI-801)의 임상적 유용성에 관한 고찰)

  • Choi, Hye Sook;Choi, Cheon Woong;Park, Myung Jae;Kang, Hong Mo;Yoo, Hong Ji
    • Tuberculosis and Respiratory Diseases
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    • v.62 no.4
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    • pp.276-283
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    • 2007
  • Background: A national health care initiative recommends routine spirometry screening of all smokers over age 45 or patients with respiratory symptoms. In response to the recommendation, new, simple, and inexpensive desktop spirometers for the purpose of promoting widespread spirometric screening were marketed. The performance of these spirometers was evaluated in vivo testing with healthy subjects. However, the clinical setting allows spirometric assessment of various pathologic combinations of flow and volume. Objective: The aim of this study was to compare the accuracy of a desktop spirometer to a standard laboratory spirometer, in a clinical setting with pathologic pulmonary function. Method: In a health check-up center, where screening pulmonary funct test was performed using the HI-801 spirometer. Subjects who revealed the ventilation defect in screening spirometry, performed the spirometry again using the standard Vmax spectra 22d spirometer in a tertiary care hospital pulmonary function laboratory. Pulmonary function test with both spirometer was performed according to the guidelines of the American Thoracic Society. Results: 109 patients were enrolled. Pulmonary function measurements (FVC, $FEV_1$, PEFR, FEF25%-75%) from the HI-801 correlated closely (r=0.94, 0.93, 0.81, 0.84, respectively) with those performed with the Vmax spectra 22d and showed the good limits of agreement and differences between the 2 devices; FVC +0.35 L, $FEV_1$ +0.16 L, PEFR +1.85 L/s, FEF25%-75%-0.13 L/s. With the exception of $FEV_1$, FEF25%-75%, these differences were significant(p<0.05) but small. Conclusion: The HI-801 spirometer is comparable to the standard laboratory spirometer, Vmax spectra 22d, with high accurary for $FEV_1$ and FVC and acceptable differences for clinical use.

Effect of Ventilating System on the Performance of Broiler Chicks in an Environmental Controlled Cage House (무창계사의 환기 시스템이 케이지 사육 육계의 초기 생산성에 미치는 영향)

  • HwangBo J.;Hong E.C.;Lee B.S.;Bae H.D.;Lee S.J.;Cho S.B.;Kim H.K.;Kim J.H.;Park B.S.;Song J.I.
    • Korean Journal of Poultry Science
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    • v.33 no.1
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    • pp.57-63
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    • 2006
  • This study was conducted to investigate the effect of ventilating system of environmental controlled broiler house on broiler production. Three hundred eighty four broiler chicks (Hubbard, mean live weight of $44.5{\pm}2.0g/bird$) were reared for 2 wk. The results of the present study were summarized as follows : 1. Ammonia gas production was lower in the second and the third floors of cages compared with first floor of cages 13.5 and 13.5 vs 14.6 ppm, respectively). The observations of ammonia production in the morning and afternoon were similar. The production of carbon dioxide was not different between morning and afternoon, but it was tended to decrease in the forth floor of cages due to a fresh air 2. A wind velocity in the enclosed house was similar across lower, middle and upper section (0.57m/sec, 0.22m/sec and 0.04msec, respectively). In order to maintain an optimal air flow velocity in the cages, the duct entrance was punched, and then the air flow was full-round in the overall space in the cage. 3. Daily liveweight gain, feed intakes, and feed efficiency were not significant differences among treatments during whole experimental period (P>0.05). Therefore, the present results showed that temperature, moisture and atmosphere controlling were desirable, and air flew evenly in the cage.

Early Response of Cardiopulmonary Exercise Test(CPET) in Patients with Locally Advanced Non-Small Cell Lung Cancer Treated with Radiation (방사선 치료 후 폐암환자의 운동부하 심.폐 기능의 초기변화)

  • Shin, Kyeong-Cheol;Lee, Deok-Hee;Lee, Kwan-Ho
    • Tuberculosis and Respiratory Diseases
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    • v.49 no.4
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    • pp.466-473
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    • 2000
  • Background : Patients with locally advanced non-small cell lung cancer are often treated with radiation alone or in combination with chemotherapy. Both modalities have a potentially damaging effect on pulmonary function. In order to examine changes in the cardiopulmonary exercise function of patients with locally advanced non-small cell lung cancer before and after conventional radiotherapy, we conducted a prospective study involving patients with such cancer, that had received radiation therapy. Method : Resting pulmonary function test, thoracic radiographic finding and cardiopulmonary exercise test(CPET) were assessed prior to and 4 weeks following radiation therapy in 11 male patients with locally advanced non-small cell lung cancer. Patient with endobronchial mass were excluded. Results : The forces vital capacity (FVC), forced expiratory volume in 1 second ($FEV_1$ and maximal voluntary ventilation (MVV) did not decreased between before and 4 weeks after radiation but the diffusing capacity (DLCO) had decreased by 11% 4 weeks after radiation, which was not statistically significant. No changes in maximal oxygen consumption ($VO_2$max), carbon dioxide production ($VCO_2$), exercise time and work load were attributed to radiation therapy. Follow up cardiopulmonary exercise testing revealed unchanged cardiovascular function, ventilatory function and gas exchange. No difference in cardiopulmonary exercise test performance was observed between pre- and post-radiation. Conclusion : Cardiopulmonary exercise function did not decrease within the short-term after the radiation of patients with locally advanced non-small cell lung cancer.

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Study of system using load cell for real time weight sensing of artificial incubator (인공부화기의 실시간 중량감지를 위한 로드셀을 이용한 시스템 연구)

  • jeong, Jin-hyoung;Kim, Ae-kyung;Lee, Sang-Sik
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.11 no.2
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    • pp.144-149
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    • 2018
  • The eggs are incubated for 18 days through the generator and incubated in the developing incubator. During the developmental period, the weight loss of the fetus is correlated with the ventricular formation, and the proper ventricular formation is also associated with the healthy embryonic hatching and the egg hatching rate. However, in the incubator period of the domestic hatchery, it is a reality to acquire the resultant side by the Iranian standard weight measurement with the experience of the hatchery and the person concerned and the development period without the apparatus for measuring the present weight. As a result, prevalence of early mortality, hunger and illness during hatching are frequent. Monitoring the reduction of weaning weight is crucial to obtaining chick quality and hatching performance with weight changes within the development machine. Water loss is different depending on the size of eggs, egg shell, and elder group. We can expect to increase the hatching rate by measuring the weight change in real time and optimizing the ventilation change accordingly. There is a need to develop a real-time measurement system that can control 10 to 13% reduction of the total weight during hatching. The system through this study is a way to check the one - time directly when moving the existing egg, and it is impossible to control the measurement of the fetal water evaporation within the development period. Unlike systems that do not affect the hatching rate, four load cells are connected in parallel on the Arduino sketch board and the AT-command command is used to connect the mobile phone and computer in real time. The communication speed of Bluetooth was set to 15200 to match the communication speed of Arduino and Hyper-terminal program. The real - time monitoring system was designed to visually check the change of the weight of the fetus in the artificial incubator. In this way, we aimed to improve the hatching rate and health condition of the hatching eggs.

Environmental Prediction in Greenhouse According to Modified Greenhouse Structure and Heat Exchanger Location for Efficient Thermal Energy Management (효율적인 열에너지 관리를 위한 온실 형상 및 열 교환 장치 위치 개선에 따른 온실 내부 환경 예측)

  • Jeong, In Seon;Lee, Chung Geon;Cho, La Hoon;Park, Sun Yong;Kim, Seok Jun;Kim, Dae Hyun;Oh, Jae-Heun
    • Journal of Bio-Environment Control
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    • v.30 no.4
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    • pp.278-286
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    • 2021
  • In this study, based on the Computational Fluid Dynamics (CFD) simulation model developed through previous study, inner environmenct of the modified glass greenhouse was predicted. Also, suggested the optimal shape of the greenhouse and location of the heat exchangers for heat energy management of the greenhouse using the developed model. For efficient heating energy management, the glass greenhouse was modified by changing the cross-section design and the location of the heat exchanger. The optimal cross-section design was selected based on the cross-section design standard of Republic of Korea's glass greenhouse, and the Fan Coil Unit(FCU) and the radiating pipe were re-positioned based on "Standard of greenhouse environment design" to enhance energy saving efficiency. The simulation analysis was performed to predict the inner temperature distribution and heat transfer with the modified greenhouse structure using the developed inner environment prediction model. As a result of simulation, the mean temperature and uniformity of the modified greenhouse were 0.65℃, 0.75%p higher than those of the control greenhouse, respectively. Also, the maximum deviation decreased by an average of 0.25℃. And the mean age of air was 18 sec. lower than that of the control greenhouse. It was confirmed that efficient heating energy management was possible in the modified greenhouse, when considered the temperature uniformity and the ventilation performance.

Effects of Percutaneous Balloon Mitral Valvuloplasty on Static Lung Function and Exercise Performance (승모판협착증 환자에서 경피적 풍선확장판막성형술의 폐기능 및 운동부하 검사에 대한 효과)

  • Kim, Yong-Tae;Kim, Woo-Sung;Lim, Chae-Man;Chin, Jae-Yong;Koh, Youn-Suck;Kim, Jae-Joong;Park, Seong-Wook;Park, Seung-Jung;Lee, Jong-Koo;Kim, Won-Dong
    • Tuberculosis and Respiratory Diseases
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    • v.41 no.1
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    • pp.1-10
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    • 1994
  • Background: Patients with mitral stenosis(MS) have been demonstrated to have a variable degree of pulmonary dysfunction and exercise impairment. The hemodynamic changes of MS can be reversed after percutaneous mitral balloon valvuloplasty(PMV), but the extent and time course of the imporvement in pulmonary function and exercise capacity are not defined. Methods: In order to investigate the early(3 weeks or less)and late(3 months or more) effects of PMV on pulmonary function and determine if the pulmonary dysfunction is reversible even in patients with moderate to severe pulmonary hypertension, we performed the spirometry, measurements of diffusing capacity and lung volumes, and incremental exercise tests in patients with MS before and after PMV. Results: In 46 patients with MS(age: $40{\pm}12$years, male to female ratio: 1:2, mitral valve area: $0.8{\pm}0.2cm^2$) there was a significant increase in FVC(P<0.0025), $FEV_1$(P<0.001), $FEF_{25-75%}$(P<0.001, $FEF_{50%}$(P<0.001), PEF(P<0.0005), MVV(P<0.005), $\dot{V}O_2$max (P<0.0001), and AT(P<0.0001) after average 10 days of PMV. Also there was a significant decrease in DLco(P<0.0001) and DL/VA(P<0.0001). At later($5{\pm}2$months) follow-up in 11 patients, there was no further improvement in any parameters of pulmonary function and exercise test. Twenty nine patients with sinus rhythm were divided into 16 patients with pulmonary arterial pressure(PAP) more than 35mmHg and/or tricuspid regurgitation grade n or more(group A) and 13 patients with PAP less than 35mmHg(group B). Group A Patients had significantly lower FVC(P<0.001), $FEV_1$(P<0.001), DLco(P<0.05), $\dot{V}O_2$ max(P<0.025) and mitral valve area(P<0.025) than group B patients. Group A patients after PMV, showed significant increase in FVC(P<0.001), maximum $O_2$ pulse(P<0.00001) and $\dot{V}O_2$ max(P<0.00025). Both group showed an increase in AT(P<0.0001, P<0.005), but group A showed greater decrease in $\dot{V}E/\dot{V}O_2$ and $\dot{V}E/\dot{V}CO_2$ both at AT(P<0.001, P<0.001) and $\dot{V}O_2$ max(P<0.0001, P<0.0001) after PMV compared with group B. Conclusion: These data suggest that patients with MS can show increased pulmonary function and exercise performance within 1 month after PMV. Patients with moderate to severe pulmonary hypertension had a significant increase in exercise performance compared with those with mild to no pulmonary hypertension and it is thought to be related to a significat decrease of ventilation for a given oxygen consumption at maximum exercise.

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Study on PM10, PM2.5 Reduction Effects and Measurement Method of Vegetation Bio-Filters System in Multi-Use Facility (다중이용시설 내 식생바이오필터 시스템의 PM10, PM2.5 저감효과 및 측정방법에 대한 연구)

  • Kim, Tae-Han;Choi, Boo-Hun
    • Journal of the Korean Institute of Landscape Architecture
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    • v.48 no.5
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    • pp.80-88
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    • 2020
  • With the issuance of one-week fine dust emergency reduction measures in March 2019, the public's anxiety about fine dust is increasingly growing. In order to assess the application of air purifying plant-based bio-filters to public facilities, this study presented a method for measuring pollutant reduction effects by creating an indoor environment for continuous discharge of particle pollutants and conducted basic studies to verify whether indoor air quality has improved through the system. In this study conducted in a lecture room in spring, the background concentration was created by using mosquito repellent incense as a pollutant one hour before monitoring. Then, according to the schedule, the fine dust reduction capacity was monitored by irrigating for two hours and venting air for one hour. PM10, PM2.5, and temperature & humidity sensors were installed two meters front of the bio-filters, and velocity probes were installed at the center of the three air vents to conduct time-series monitoring. The average face velocity of three air vents set up in the bio-filter was 0.38±0.16 m/s. Total air-conditioning air volume was calculated at 776.89±320.16㎥/h by applying an air vent area of 0.29m×0.65m after deducing damper area. With the system in operation, average temperature and average relative humidity were maintained at 21.5-22.3℃, and 63.79-73.6%, respectively, which indicates that it satisfies temperature and humidity range of various conditions of preceding studies. When the effects of raising relatively humidity rapidly by operating system's air-conditioning function are used efficiently, it would be possible to reduce indoor fine dust and maintain appropriate relative humidity seasonally. Concentration of fine dust increased the same in all cycles before operating the bio-filter system. After operating the system, in cycle 1 blast section (C-1, β=-3.83, β=-2.45), particulate matters (PM10) were lowered by up to 28.8% or 560.3㎍/㎥ and fine particulate matters (PM2.5) were reduced by up to 28.0% or 350.0㎍/㎥. Then, the concentration of find dust (PM10, PM2.5) was reduced by up to 32.6% or 647.0㎍/㎥ and 32.4% or 401.3㎍/㎥ respectively through reduction in cycle 2 blast section (C-2, β=-5.50, β=-3.30) and up to 30.8% or 732.7㎍/㎥ and 31.0% or 459.3㎍/㎥ respectively through reduction in cycle 3 blast section (C-3, β=5.48, β=-3.51). By referring to standards and regulations related to the installation of vegetation bio-filters in public facilities, this study provided plans on how to set up objective performance evaluation environment. By doing so, it was possible to create monitoring infrastructure more objective than a regular lecture room environment and secure relatively reliable data.

The Effect of Common Features on Consumer Preference for a No-Choice Option: The Moderating Role of Regulatory Focus (재몰유선택적정황하공동특성대우고객희호적영향(在没有选择的情况下共同特性对于顾客喜好的影响): 조절초점적조절작용(调节焦点的调节作用))

  • Park, Jong-Chul;Kim, Kyung-Jin
    • 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."